JarroVGIT commented on code in PR #1854: URL: https://github.com/apache/iceberg-rust/pull/1854#discussion_r2538714249
########## docs/rfcs/0001_kernel.md: ########## @@ -0,0 +1,192 @@ +<!-- + ~ 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. +--> + +# RFC: Extract `iceberg-kernel` for Pluggable Execution Layers + +## Background + +Issue #1819 proposes decoupling the protocol/metadata/plan logic that currently lives inside the `iceberg` crate so that it can serve as a reusable “kernel,” similar to the approach taken by [delta-kernel-rs](https://github.com/delta-io/delta-kernel-rs). Today the `iceberg` crate simultaneously exposes the public trait surface and the default engine (Tokio runtime, opendal-backed FileIO, Arrow readers, etc.). This tight coupling makes it difficult for downstream projects to embed Iceberg metadata while providing their own storage, runtime, or execution stack. + +## Goals and Scope + +- **Full read & write coverage**: the kernel must contain every protocol component required for both scan planning and transactional writes (append, rewrite, commit, etc.). +- **No default runtime dependency**: the kernel defines a `Runtime` trait instead of depending on Tokio or Smol. Review Comment: The point of this RFC (iiuc) is to make a IO-agnostic core of the Iceberg specification. Sometimes this is referred to as sans-io. This core would encapsulate the core logic and workings of Iceberg, without a dependency. The module that you refer to is an example of the opposite of this model. At present, the current crate (`iceberg`) supports Tokio or Smol, but no other runtime. If you want to add a runtime, you would have to change this crate. With a sans-io approach, you can add runtimes by adding other crates. I could create my own runtime, and then publish a `iceberg-runtime-mysuperruntime` crate, without the `iceberg-kernel` crate ever being aware of its existence. So, I don't think it is possible (or at least, wise) to just split the current module in another crate in the spirit of this RFC, and have the kernel depend on it. The kernel defines the abstraction, and the "plugin" crate implements that abstraction (and therefor, depends on the kernel, not the other way around). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
