[I] Save field-level metadata when writing parquet files [arrow-go]

[via GitHub]

shachibista opened a new issue, #365:
URL: https://github.com/apache/arrow-go/issues/365

   ### Describe the enhancement requested
   
   Field level metadata on arrow schema is not persisted into the parquet 
files. 
   
   Here's a test script:
   
   ```golang
   package main
   
   import (
        "fmt"
        "os"
   
        "github.com/apache/arrow-go/v18/arrow"
        "github.com/apache/arrow-go/v18/arrow/array"
        "github.com/apache/arrow-go/v18/arrow/memory"
        "github.com/apache/arrow-go/v18/parquet"
        "github.com/apache/arrow-go/v18/parquet/compress"
        "github.com/apache/arrow-go/v18/parquet/pqarrow"
   )
   
   func main() {
        schema := arrow.NewSchema([]arrow.Field{
                {Name: "id", Type: arrow.BinaryTypes.Binary, Metadata: 
arrow.MetadataFrom(map[string]string{
                        "external_type": "uuid",
                })},
                {Name: "name", Type: arrow.BinaryTypes.String},
        }, nil)
   
        out, err := os.Create("test.parquet")
        if err != nil {
                fmt.Println(err)
                return
        }
   
        wr, err := pqarrow.NewFileWriter(
                schema,
                out,
                parquet.NewWriterProperties(
                        parquet.WithCompression(compress.Codecs.Snappy),
                        parquet.WithDataPageVersion(parquet.DataPageV2),
                        parquet.WithVersion(parquet.V2_LATEST),
                ),
                pqarrow.DefaultWriterProps(),
        )
        if err != nil {
                fmt.Println(err)
                return
        }
        defer wr.Close()
   
        rb := array.NewRecordBuilder(memory.DefaultAllocator, schema)
        defer rb.Release()
   
        rb.Field(0).AppendNull()
        rb.Field(1).AppendNull()
   
        wr.Write(rb.NewRecord())
   }
   ```
   
   ```python
   import pyarrow.parquet as pq
   
   table = pq.read_table("test.parquet")
   field = table.schema.field("id")
   print(field.metadata)  # prints None
   ```
   
   ### Component(s)
   
   Parquet


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