feat: return raw bytes from call_runner for non-JSON responses

[rickstaa]

Closes the last gap after #25: the buffered call_runner path required every response to be a JSON object, so binary-returning apps (an image, say — the hf-inference text-to-image API returns raw image/jpeg bytes) forced a base64-in-JSON shim into every runner and client. Streaming already handled bytes (stream=True → aiter_bytes()); this brings the buffered path to parity, mirroring the familiar requests model (r.json() / r.content vs iter_content).

What

• http.request_data() — same request semantics and error mapping as request_json, but returns (body_bytes, content_type) without assuming JSON. request_json is now a thin wrapper over it (fetch + parse), behavior unchanged.
• call_runner (non-stream): JSON content types parse into result.data exactly as before (including the strict object check and session_id pickup). Any other content type returns result.raw (bytes) + result.content_type instead of raising "expected JSON object".
• LiveRunnerCallResult: new optional raw and content_type fields; content_type is also set on JSON results.
• Payment path untouched: the 402 challenge raises on status before any body handling, so paid calls work identically for JSON and binary responses.

Compatibility

Strictly additive: every response that succeeded before behaves identically. The only changed case is one that previously raised — a non-JSON content type — which now succeeds with bytes. One edge note: a server returning JSON with a non-JSON content type (e.g. bare text/plain) now lands in raw instead of being parsed; aiohttp's json_response (what the examples use) always sets application/json.

Why

With this, a runner that fronts a bytes-returning API needs no transform at all — the example-apps api-proxy can drop its base64 envelope, and a runner can literally be a stock nginx proxy_pass (See livepeer/runner-app-examples#45).

Tested

tests/test_call_runner_raw.py (5 cases against a live aiohttp server): JSON unchanged incl. session_id, binary → raw + content_type, invalid JSON with JSON content type still raises, JSON array still rejected, HTTP errors still raise. Full suite passes (14).

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on base/target branches other than the default branch.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: ed72cebc-560d-4b89-befe-2049936651fb

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}