jayshrivastava opened a new issue, #24331:
URL: https://github.com/apache/datafusion/issues/24331

   ### Is your feature request related to a problem or challenge?
   
   ComposedPhysicalExtensionCodec should identify codecs by stable ID instead 
of list position
   
   `ComposedPhysicalExtensionCodec` records the position of each codec in the 
`DataEncoderTuple`:
   
   ```rust
   struct DataEncoderTuple {
       pub encoder_position: u32,
       pub blob: Vec<u8>,
   }
   
   The problem is that if someone adds, removes, or reorders a codec, you get 
really confusing error messages. For example:
   1. A writer with [CodecA, CodecB] encodes protobuf `A` and specifies 
`encoder_position: 0`
   2. A reader with [CodecB, CodecA] decodes the proto using `encoder_position: 
0` and errors with "CodecB cannot decode message"
   ```
   It's hard to see that this was caused a breaking protocol change. Since both 
codecs are present, it doesn't seem like a breaking change, but it is.
   
   
   ### Describe the solution you'd like
   
   Maybe we can introduce an id to look up encoders:
   ```rust
   struct DataEncoderTuple {
         // Retained for decoding payloads written by older versions.
         pub encoder_position: u32,
         pub blob: Vec<u8>,
         pub codec_id: Option<String>,
     }
   
     Decoding would:
   
     1. Use codec_id when present.
     2. Return an explicit error containing the unknown identifier when it is 
not registered.
     3. Fall back to encoder_position for legacy payloads.
   ```
   
   ### Describe alternatives you've considered
   
   _No response_
   
   ### Additional context
   
   _No response_


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