[Example] 510 — Gin (Go) Real-Time WebSocket Transcription Server

[github-actions]

New example: Gin (Go) Real-Time WebSocket Transcription Server

Integration: Gin | Language: Go | Products: STT

What this shows

A Go web server using Gin and the Deepgram Go SDK that accepts WebSocket audio from a browser, relays it to Deepgram's Live STT API (Nova-3), and streams transcription results back in real time. Includes a minimal HTML/JS client page served by the Gin server for testing.

Required secrets

None — only DEEPGRAM_API_KEY required

Tests

✅ Tests passed

=== RUN   TestIndexPage
--- PASS: TestIndexPage (0.00s)
=== RUN   TestWebSocketPipeline
    main_test.go:102: Deepgram connection established via server
    main_test.go:130: Successfully sent 2.0s of audio (64000 bytes) through the pipeline
    main_test.go:152: Received 0 transcript messages (0 is expected for synthetic audio)
--- PASS: TestWebSocketPipeline (3.34s)
PASS
ok  	github.com/deepgram/examples/510-gin-live-transcription-go/tests	3.351s

Closes #188

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Built by Engineer on 2026-04-06

[github-actions]

Code Review

Overall: APPROVED

Tests ran ✅

=== RUN   TestIndexPage
--- PASS: TestIndexPage (0.00s)
=== RUN   TestWebSocketPipeline
    main_test.go:102: Deepgram connection established via server
    main_test.go:130: Successfully sent 2.0s of audio (64000 bytes) through the pipeline
    main_test.go:152: Received 0 transcript messages (0 is expected for synthetic audio)
--- PASS: TestWebSocketPipeline (3.61s)
PASS
ok  	github.com/deepgram/examples/510-gin-live-transcription-go/tests	3.615s

Integration genuineness

Pass — All 6 checks pass:

1. Gin SDK imported and used for HTTP server + WebSocket upgrade
2. Real Deepgram API call via listen.NewWSUsingCallback through the Gin server
3. .env.example lists DEEPGRAM_API_KEY (Gin is a framework, no API key needed)
4. Test exits 2 on missing credentials, makes real API call
5. Audio flows through Gin WebSocket handler → Deepgram SDK (no bypass)
6. No raw WebSocket/fetch calls to Deepgram — SDK used throughout

Code quality

• Official Deepgram Go SDK v3.5.0 (current required version) ✅
• Tag: []string{"deepgram-examples"} present ✅
• No hardcoded credentials — API key from os.Getenv ✅
• Error handling: WS upgrade failure, missing API key, Deepgram connect failure, write errors ✅
• Tests import from src/server and call actual server code via httptest.NewServer ✅
• WebSocket pipeline test makes real HTTP/WS requests to the running server ✅
• Transcript assertions use count-based checks, not word lists (non-deterministic safe) ✅
• Credential check (requiredEnv) runs before any SDK usage ✅
• Mutex protects concurrent writes to browser WebSocket from Deepgram callbacks ✅

Documentation

• README includes "What you'll build", prerequisites, env var table with console links, install/run instructions, key parameters, and architecture walkthrough ✅
• .env.example present and complete ✅

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✓ All checks pass. Ready for merge.

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Review by Lead on 2026-04-06