Xuanwo commented on code in PR #765:
URL: https://github.com/apache/iceberg-rust/pull/765#discussion_r1885019802
##########
crates/iceberg/src/puffin/compression.rs:
##########
@@ -15,9 +15,12 @@
// specific language governing permissions and limitations
// under the License.
+use serde::{Deserialize, Serialize};
+
use crate::{Error, ErrorKind, Result};
-#[derive(Debug, PartialEq, Eq, Clone, Copy, Default)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Default, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
/// Data compression formats
Review Comment:
I usually prefer to keep comments at the top before `#[derive]` to make them
easier to find. This also provides more space for writing lengthy comments,
which may include examples.
```rust
/// Data compression formats
#[derive(Debug, PartialEq, Eq, Clone, Copy, Default, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
```
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Index range is out of bounds.",
+ ))
+ }
+
+ fn decode_flags(footer_bytes: &[u8]) -> Result<HashSet<Flag>> {
+ let mut flags = HashSet::new();
+ for byte_number in 0..FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH {
+ let byte_offset = footer_bytes.len()
+ - usize::from(FileMetadata::MAGIC_LENGTH)
Review Comment:
The same, we can use `FileMetadata::MAGIC_LENGTH as usize`
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
Review Comment:
Please note that we usually need to avoid reading small bytes from cloud
storage. Therefore, we will need something like prefetching, which will read a
large amount of data capable of holding the entire footer. We can implement
this optimization in a separate PR.
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
Review Comment:
Let's do early return:
```
if bytes == FileMetadata::MAGIC {
return Ok(())
}
...
```
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
Review Comment:
If this error doesn't occur often, how about writing to them directly? I
believe we won't need to change them frequently. I tend to optimize for reading
code.
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Index range is out of bounds.",
+ ))
+ }
+
+ fn decode_flags(footer_bytes: &[u8]) -> Result<HashSet<Flag>> {
+ let mut flags = HashSet::new();
+ for byte_number in 0..FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH {
+ let byte_offset = footer_bytes.len()
+ - usize::from(FileMetadata::MAGIC_LENGTH)
+ - usize::from(FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH)
+ + usize::from(byte_number);
+
+ let mut flag_byte = match footer_bytes.get(byte_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(byte) => Ok(*byte),
+ }?;
+ let mut bit_number = 0;
+ while flag_byte != 0 {
+ if flag_byte & 0x1 != 0 {
+ match Flag::from(&(ByteNumber(byte_number),
BitNumber(bit_number))) {
+ Some(flag) => flags.insert(flag),
+ None => {
+ return Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Unknown flag byte {} and bit {}
combination",
+ byte_number, bit_number
+ ),
+ ))
+ }
+ };
+ }
+ flag_byte >>= 1;
+ bit_number += 1;
+ }
+ }
+ Ok(flags)
+ }
+
+ fn extract_footer_payload_as_str(
+ footer_bytes: &[u8],
+ footer_payload_length: u32,
+ ) -> Result<String> {
+ let flags = FileMetadata::decode_flags(footer_bytes)?;
+ let footer_compression_codec = if
flags.contains(&Flag::FooterPayloadCompressed) {
+ CompressionCodec::Lz4
+ } else {
+ CompressionCodec::None
+ };
+
+ let start_offset = usize::from(FileMetadata::MAGIC_LENGTH);
+ let end_offset =
+ usize::from(FileMetadata::MAGIC_LENGTH) +
usize::try_from(footer_payload_length)?;
+ let footer_payload_bytes = match
footer_bytes.get(start_offset..end_offset) {
Review Comment:
Let's use `ok_or_else` to simplify the code
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
Review Comment:
Will we have other flags?
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Index range is out of bounds.",
+ ))
+ }
+
+ fn decode_flags(footer_bytes: &[u8]) -> Result<HashSet<Flag>> {
+ let mut flags = HashSet::new();
+ for byte_number in 0..FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH {
+ let byte_offset = footer_bytes.len()
+ - usize::from(FileMetadata::MAGIC_LENGTH)
+ - usize::from(FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH)
+ + usize::from(byte_number);
+
+ let mut flag_byte = match footer_bytes.get(byte_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(byte) => Ok(*byte),
+ }?;
+ let mut bit_number = 0;
+ while flag_byte != 0 {
+ if flag_byte & 0x1 != 0 {
+ match Flag::from(&(ByteNumber(byte_number),
BitNumber(bit_number))) {
+ Some(flag) => flags.insert(flag),
+ None => {
+ return Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Unknown flag byte {} and bit {}
combination",
+ byte_number, bit_number
+ ),
+ ))
+ }
+ };
+ }
+ flag_byte >>= 1;
+ bit_number += 1;
+ }
+ }
+ Ok(flags)
+ }
+
+ fn extract_footer_payload_as_str(
+ footer_bytes: &[u8],
+ footer_payload_length: u32,
+ ) -> Result<String> {
+ let flags = FileMetadata::decode_flags(footer_bytes)?;
+ let footer_compression_codec = if
flags.contains(&Flag::FooterPayloadCompressed) {
+ CompressionCodec::Lz4
+ } else {
+ CompressionCodec::None
+ };
+
+ let start_offset = usize::from(FileMetadata::MAGIC_LENGTH);
+ let end_offset =
+ usize::from(FileMetadata::MAGIC_LENGTH) +
usize::try_from(footer_payload_length)?;
+ let footer_payload_bytes = match
footer_bytes.get(start_offset..end_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(data) => Ok(data),
+ }?;
+ let decompressed_footer_payload_bytes =
+ footer_compression_codec.decompress(footer_payload_bytes.into())?;
+
+ match String::from_utf8(decompressed_footer_payload_bytes) {
Review Comment:
Let's use `map_err` to simplify the code
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
Review Comment:
We can use `FileMetadata::FOOTER_STRUCT_LENGTH as u64` for simple
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Index range is out of bounds.",
+ ))
+ }
+
+ fn decode_flags(footer_bytes: &[u8]) -> Result<HashSet<Flag>> {
+ let mut flags = HashSet::new();
+ for byte_number in 0..FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH {
+ let byte_offset = footer_bytes.len()
+ - usize::from(FileMetadata::MAGIC_LENGTH)
+ - usize::from(FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH)
+ + usize::from(byte_number);
+
+ let mut flag_byte = match footer_bytes.get(byte_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(byte) => Ok(*byte),
+ }?;
+ let mut bit_number = 0;
+ while flag_byte != 0 {
+ if flag_byte & 0x1 != 0 {
+ match Flag::from(&(ByteNumber(byte_number),
BitNumber(bit_number))) {
+ Some(flag) => flags.insert(flag),
+ None => {
+ return Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Unknown flag byte {} and bit {}
combination",
+ byte_number, bit_number
+ ),
+ ))
+ }
+ };
+ }
+ flag_byte >>= 1;
+ bit_number += 1;
+ }
+ }
+ Ok(flags)
+ }
+
+ fn extract_footer_payload_as_str(
+ footer_bytes: &[u8],
+ footer_payload_length: u32,
+ ) -> Result<String> {
+ let flags = FileMetadata::decode_flags(footer_bytes)?;
+ let footer_compression_codec = if
flags.contains(&Flag::FooterPayloadCompressed) {
+ CompressionCodec::Lz4
+ } else {
+ CompressionCodec::None
+ };
+
+ let start_offset = usize::from(FileMetadata::MAGIC_LENGTH);
+ let end_offset =
+ usize::from(FileMetadata::MAGIC_LENGTH) +
usize::try_from(footer_payload_length)?;
+ let footer_payload_bytes = match
footer_bytes.get(start_offset..end_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(data) => Ok(data),
+ }?;
+ let decompressed_footer_payload_bytes =
+ footer_compression_codec.decompress(footer_payload_bytes.into())?;
+
+ match String::from_utf8(decompressed_footer_payload_bytes) {
+ Err(src) => Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Footer is not a valid UTF-8 string",
+ )
+ .with_source(src)),
+ Ok(str) => Ok(str),
+ }
+ }
+
+ fn from_json_str(string: &str) -> Result<FileMetadata> {
+ match serde_json::from_str::<FileMetadata>(string) {
+ Ok(file_metadata) => Ok(file_metadata),
+ Err(src) => Err(
+ Error::new(ErrorKind::DataInvalid, "Given string is not valid
JSON")
+ .with_source(src),
+ ),
+ }
+ }
+
+ #[rustfmt::skip]
Review Comment:
Hi, it's better to let `rustfmt` to do it's work.
##########
crates/iceberg/src/puffin/metadata.rs:
##########
@@ -0,0 +1,809 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::collections::{HashMap, HashSet};
+
+use bytes::Bytes;
+use once_cell::sync::Lazy;
+use serde::{Deserialize, Serialize};
+
+use crate::io::{FileRead, InputFile};
+use crate::puffin::compression::CompressionCodec;
+use crate::{Error, ErrorKind, Result};
+
+/// Human-readable identification of the application writing the file, along
with its version.
+/// Example: "Trino version 381"
+pub(crate) const CREATED_BY_PROPERTY: &str = "created-by";
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+#[serde(rename_all = "kebab-case")]
+/// Metadata about a blob.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#blobmetadata
+pub(crate) struct BlobMetadata {
+ /// See blob types: https://iceberg.apache.org/puffin-spec/#blob-types
+ pub(crate) r#type: String,
+ /// List of field IDs the blob was computed for; the order of items is
used to compute sketches stored in the blob.
+ #[serde(rename = "fields")]
+ pub(crate) input_fields: Vec<i32>,
+ /// ID of the Iceberg table's snapshot the blob was computed from
+ pub(crate) snapshot_id: i64,
+ /// Sequence number of the Iceberg table's snapshot the blob was computed
from
+ pub(crate) sequence_number: i64,
+ /// The offset in the file where the blob contents start
+ pub(crate) offset: u64,
+ /// The length of the blob stored in the file (after compression, if
compressed)
+ pub(crate) length: usize,
+ /// The compression codec used to compress the data
+ #[serde(skip_serializing_if = "CompressionCodec::is_none")]
+ #[serde(default)]
+ pub(crate) compression_codec: CompressionCodec,
+ /// Arbitrary meta-information about the blob
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ pub(crate) properties: HashMap<String, String>,
+}
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+pub(crate) enum Flag {
+ FooterPayloadCompressed,
+}
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct ByteNumber(pub u8);
+
+#[derive(PartialEq, Eq, Hash)]
+pub(crate) struct BitNumber(pub u8);
+
+static FLAGS_BY_BYTE_AND_BIT: Lazy<HashMap<(ByteNumber, BitNumber), Flag>> =
Lazy::new(|| {
+ let mut m = HashMap::new();
+ m.insert(
+ (
+ Flag::FooterPayloadCompressed.byte_number(),
+ Flag::FooterPayloadCompressed.bit_number(),
+ ),
+ Flag::FooterPayloadCompressed,
+ );
+ m
+});
+
+impl Flag {
+ pub(crate) fn byte_number(&self) -> ByteNumber {
+ match self {
+ Flag::FooterPayloadCompressed => ByteNumber(0),
+ }
+ }
+
+ pub(crate) fn bit_number(&self) -> BitNumber {
+ match self {
+ Flag::FooterPayloadCompressed => BitNumber(0),
+ }
+ }
+
+ fn from(byte_and_bit: &(ByteNumber, BitNumber)) -> Option<Flag> {
+ FLAGS_BY_BYTE_AND_BIT.get(byte_and_bit).cloned()
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Clone)]
+/// Metadata about a puffin file.
+/// For more information, see:
https://iceberg.apache.org/puffin-spec/#filemetadata
+pub(crate) struct FileMetadata {
+ /// Metadata about blobs in file
+ pub(crate) blobs: Vec<BlobMetadata>,
+ #[serde(skip_serializing_if = "HashMap::is_empty")]
+ #[serde(default)]
+ /// Arbitrary meta-information, like writer identification/version.
+ pub(crate) properties: HashMap<String, String>,
+}
+
+impl FileMetadata {
+ pub(crate) const MAGIC_LENGTH: u8 = 4;
+ pub(crate) const MAGIC: [u8; FileMetadata::MAGIC_LENGTH as usize] = [0x50,
0x46, 0x41, 0x31];
+
+ // We use the term FOOTER_STRUCT to refer to the fixed-length portion of
the Footer, as illustrated below.
+ //
+ // Footer
+ // |
+ // -------------------------------------------------
+ // | |
+ // Magic FooterPayload FooterPayloadLength Flags Magic
+ // | |
+ // -----------------------------
+ // |
+ // FOOTER_STRUCT
+
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET: u8 = 0;
+ const FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_FLAGS_OFFSET: u8 =
FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_OFFSET
+ + FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH;
+ pub(crate) const FOOTER_STRUCT_FLAGS_LENGTH: u8 = 4;
+ const FOOTER_STRUCT_MAGIC_OFFSET: u8 =
+ FileMetadata::FOOTER_STRUCT_FLAGS_OFFSET +
FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH;
+ pub(crate) const FOOTER_STRUCT_LENGTH: u8 =
+ FileMetadata::FOOTER_STRUCT_MAGIC_OFFSET + FileMetadata::MAGIC_LENGTH;
+
+ fn check_magic(bytes: &[u8]) -> Result<()> {
+ if bytes != FileMetadata::MAGIC {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Bad magic value: {:?} should be {:?}",
+ bytes,
+ FileMetadata::MAGIC
+ ),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ async fn read_footer_payload_length(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ ) -> Result<u32> {
+ let start = input_file_length -
u64::from(FileMetadata::FOOTER_STRUCT_LENGTH);
+ let end = start +
u64::from(FileMetadata::FOOTER_STRUCT_PAYLOAD_LENGTH_LENGTH);
+ let footer_payload_length_bytes = file_read.read(start..end).await?;
+ let mut buf = [0; 4];
+ buf.copy_from_slice(&footer_payload_length_bytes);
+ let footer_payload_length = u32::from_le_bytes(buf);
+ Ok(footer_payload_length)
+ }
+
+ async fn read_footer_bytes(
+ file_read: &dyn FileRead,
+ input_file_length: u64,
+ footer_payload_length: u32,
+ ) -> Result<Bytes> {
+ let footer_length = u64::from(footer_payload_length)
+ + u64::from(FileMetadata::FOOTER_STRUCT_LENGTH)
+ + u64::from(FileMetadata::MAGIC_LENGTH);
+ let start = input_file_length - footer_length;
+ let end = input_file_length;
+ file_read.read(start..end).await
+ }
+
+ fn err_out_of_bounds<T>() -> Result<T> {
+ Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Index range is out of bounds.",
+ ))
+ }
+
+ fn decode_flags(footer_bytes: &[u8]) -> Result<HashSet<Flag>> {
+ let mut flags = HashSet::new();
+ for byte_number in 0..FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH {
+ let byte_offset = footer_bytes.len()
+ - usize::from(FileMetadata::MAGIC_LENGTH)
+ - usize::from(FileMetadata::FOOTER_STRUCT_FLAGS_LENGTH)
+ + usize::from(byte_number);
+
+ let mut flag_byte = match footer_bytes.get(byte_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(byte) => Ok(*byte),
+ }?;
+ let mut bit_number = 0;
+ while flag_byte != 0 {
+ if flag_byte & 0x1 != 0 {
+ match Flag::from(&(ByteNumber(byte_number),
BitNumber(bit_number))) {
+ Some(flag) => flags.insert(flag),
+ None => {
+ return Err(Error::new(
+ ErrorKind::DataInvalid,
+ format!(
+ "Unknown flag byte {} and bit {}
combination",
+ byte_number, bit_number
+ ),
+ ))
+ }
+ };
+ }
+ flag_byte >>= 1;
+ bit_number += 1;
+ }
+ }
+ Ok(flags)
+ }
+
+ fn extract_footer_payload_as_str(
+ footer_bytes: &[u8],
+ footer_payload_length: u32,
+ ) -> Result<String> {
+ let flags = FileMetadata::decode_flags(footer_bytes)?;
+ let footer_compression_codec = if
flags.contains(&Flag::FooterPayloadCompressed) {
+ CompressionCodec::Lz4
+ } else {
+ CompressionCodec::None
+ };
+
+ let start_offset = usize::from(FileMetadata::MAGIC_LENGTH);
+ let end_offset =
+ usize::from(FileMetadata::MAGIC_LENGTH) +
usize::try_from(footer_payload_length)?;
+ let footer_payload_bytes = match
footer_bytes.get(start_offset..end_offset) {
+ None => FileMetadata::err_out_of_bounds(),
+ Some(data) => Ok(data),
+ }?;
+ let decompressed_footer_payload_bytes =
+ footer_compression_codec.decompress(footer_payload_bytes.into())?;
+
+ match String::from_utf8(decompressed_footer_payload_bytes) {
+ Err(src) => Err(Error::new(
+ ErrorKind::DataInvalid,
+ "Footer is not a valid UTF-8 string",
+ )
+ .with_source(src)),
+ Ok(str) => Ok(str),
+ }
+ }
+
+ fn from_json_str(string: &str) -> Result<FileMetadata> {
+ match serde_json::from_str::<FileMetadata>(string) {
+ Ok(file_metadata) => Ok(file_metadata),
+ Err(src) => Err(
+ Error::new(ErrorKind::DataInvalid, "Given string is not valid
JSON")
+ .with_source(src),
+ ),
+ }
+ }
+
+ #[rustfmt::skip]
+ /// Returns the file metadata about a Puffin file
+ pub(crate) async fn read(input_file: &InputFile) -> Result<FileMetadata> {
+ let file_read = input_file.reader().await?;
+
+ let first_four_bytes =
file_read.read(0..FileMetadata::MAGIC_LENGTH.into()).await?;
+ FileMetadata::check_magic(&first_four_bytes)?;
+
+ let input_file_length = input_file.metadata().await?.size;
+ let footer_payload_length =
FileMetadata::read_footer_payload_length(&file_read, input_file_length).await?;
+ let footer_bytes = FileMetadata::read_footer_bytes(&file_read,
input_file_length, footer_payload_length).await?;
+
+ let magic_length = usize::from(FileMetadata::MAGIC_LENGTH);
+ FileMetadata::check_magic(&footer_bytes[..magic_length])?;
// first four bytes of footer
Review Comment:
We can put the comment before this line.
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