Adds gzip handler to JDK http client based on header

[spicydev]

Title

Implement custom BodyHandler for GZIP decompression in JdkClientHttpRequest

Description

Problem: JDK HTTP Client doesn't automatically decompress responses.

Solution: creating a custom BodyHandler that checks Content-Encoding and applies GZIPInputStream when necessary.
Key Changes:

• Added new boolean field compressionEnabled to JdkClientHttpRequestFactory and JdkClientHttpRequest.
• Modified buildRequest() method to add Accept-Encoding header with gzip value when compression is enabled.
• Added a custom DecompressingBodyHandler that implements BodyHandler<InputStream>. The apply() method in the custom handler checks the Content-Encoding header.
• If the encoding is gzip, it uses BodySubscribers.mapping to wrap the InputStream with GZIPInputStream.
  Otherwise, it uses the default BodySubscribers.ofInputStream().

Testing Steps:

• Make an HTTP request to an endpoint that returns a gzip-encoded response (e.g., https://vpic.nhtsa.dot.gov/api/vehicles/getallmanufacturers?format=json).
• Verify that the response body is correctly decompressed and the data is accessible.

[bclozel]

Should we also support the "deflate" compression algorithm?

Also, I am wondering if we really need an option that enables compression. Should we enable this no matter what?

What do you think?

[spicydev]

Hi @bclozel, First off let me start off by apologizing for raising the PR in such bad state. I’ll work on unit tests and follow style guide once we can finalize on the requirements.

coming to your questions, Yes we can add support for multiple encoding types but following other clients like apache httpclient & netty, they only support gzip by default out of the box. I think at-least for now we can add support for gzip to JDK http client.

I think it’s better to have the control to the users but by default we can enable compression as it causes no harm but improves performance for all users.

Let me know your thoughts, based on that i can go ahead with changes.

[bclozel]

@spicydev no worries, we are here to help.

I think Apache HttpClient supports both. And so does Netty.

[spicydev]

Hi @bclozel , Need your help here. When testing the Inflater with JDK http client I'm seeing error like below
java.util.zip.ZipException: incorrect header check. Can you check the unit test once