[sentry-junior]

Adds gzip compression alongside Zstd in the server, Rust client, and Python client. Both clients now support compressed uploads and transparent download decompression. Zstd remains the default.

• GCS payload downloads send Accept-Encoding: gzip to prevent decompressive transcoding, which otherwise returns plaintext and ignores Range. This preserves stored bytes for compressed downloads and range reads. The backend HTTP client already disables automatic decompression.
• Both clients decode concatenated gzip members, including payloads assembled by multipart uploads.
• The Rust client compresses all upload body types through a generic helper that avoids extra reader and stream boxes.
• Rust batch sizing uses a conservative gzip size bound because streaming compression leaves the final size unknown. The bound uses zlib's compressBound formula without the zlib wrapper, plus gzip framing. Precompressed uploads use their exact size.
• Python shares compression handling across streaming uploads, resumable-upload spooling, and downloads.
• Python rejects unsupported compression values up front, including on Usecase. Previously, an unknown usecase encoding caused Zstd compression with an incorrect encoding label.
• Adding Compression::Gzip to the shared Rust enum breaks downstream exhaustive matches. Callers must handle the new variant or use a wildcard arm.

Closes FS-575

[linear-code]

FS-575

[codecov]

Codecov Report

❌ Patch coverage is 97.37828% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.01%. Comparing base (2612bee) to head (0246e2c).

Files with missing lines	Patch %	Lines
...ents/python/src/objectstore_client/_compression.py	92.70%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #693      +/-   ##
==========================================
+ Coverage   91.90%   92.01%   +0.11%     
==========================================
  Files         117      118       +1     
  Lines       24131    24321     +190     
==========================================
+ Hits        22178    22380     +202     
+ Misses       1953     1941      -12     

Components	Coverage Δ
Rust Backend	94.94% <100.00%> (+0.02%)	⬆️
Rust Client	84.29% <100.00%> (+1.42%)	⬆️
Python Client	93.88% <93.57%> (+0.15%)	⬆️

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[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

📋 Changelog Preview

This is how your changes will appear in the changelog.
Entries from this PR are highlighted with a left border (blockquote style).

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Python Client

• Split the signing key from the token policy: SecretKey(kid, secret_key) now only holds the EdDSA key, and TokenGenerator(key, expiry_seconds=60, permissions=None) wraps it with the token defaults and is what you pass to Client(token=...). The deprecated sign_for_scope() alias is removed. by sentry-junior in #721
  • Replace SecretKey(kid, secret_key, expiry_seconds, permissions) or TokenGenerator(kid, secret_key, ...) with TokenGenerator(SecretKey(kid, secret_key), expiry_seconds, permissions).

    # Before
    client = Client(url, token=SecretKey(kid, secret_key, expiry_seconds=300))
    
    # After
    key = SecretKey(kid, secret_key)
    client = Client(url, token=TokenGenerator(key, expiry_seconds=300))

  • Replace .sign_for_scope(...) with .token_for_scope(...).
• Remove the deprecated compression argument from Session.put() by sentry-junior in #718
  • Replace session.put(..., compression=...) with session.put(..., compress=...).
• Remove the deprecated propagate_traces argument from Client by sentry-junior in #714
  • Drop propagate_traces=... from Client(...) calls. Sentry's StdlibIntegration, enabled by default, already propagates traces on Objectstore requests.
• Add a response_content_disposition option ("inline" or "attachment") to Session.object_url() and Session.presigned_object_url(). Pre-signed URLs include it in their signature. by jan-auer in #696

Rust Client

• Remove the deprecated Session::mint_token() by sentry-junior in #717
  • Replace session.mint_token() with session.get_token().
• Remove the deprecated TokenGenerator::sign() by sentry-junior in #716
  • Replace generator.sign(&scope) with generator.create_token(&scope).sign().
• Remove the deprecated PutBuilder::compression() by sentry-junior in #715
  • Replace .compression(...) with .compress(...) on put builders.
• Usecase::new now returns a Result, and the panicking constructor is now Usecase::from_static by sentry-junior in #710
  • Replace Usecase::new("name") with Usecase::from_static("name").
  • Replace Usecase::try_new(name) with Usecase::new(name).
• Mark Error as #[non_exhaustive] so new error variants can be added without a breaking change by lcian in #706
  • Add a wildcard arm (_ => ...) to exhaustive match expressions on objectstore_client::Error.
• Remove the multipart upload API (Session::initiate_multipart_upload(), Session::resume_multipart_upload()) and the multipart feature flag by lcian in #704
  • Use resumable uploads instead.
  • Remove match arms for the removed Error::InvalidPartNumber, Error::InvalidUploadId and Error::MultipartComplete variants.

Other

• feat: Support gzip compression in server, Rust and Python clients by sentry-junior[bot] in #693

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_{🤖 This preview updates automatically when you update the PR.}

[lcian]

Looks good.

Junior, please answer my comment, and also check if we need to do anything in our Objectstore proxy endpoint in the sentry repo after this ships.

Leaving it to Jan to decide whether we want to feature flag this in the Rust client.