CaptureTweet is a small self-hostable service that captures a Tweet as an image, stores metadata, and exposes a GraphQL API for searching and retrieving Tweets and authors. The project was originally built to experiment with Google Cloud Run.

Note: The hosted instance was shut down on 2023‑12‑31 due to Twitter API pricing changes. You can still self‑host using the instructions below.

• Backend: Go + gqlgen GraphQL API
• Storage: Go Cloud Docstore (Firestore or in‑memory for dev)
• Search: Algolia
• Pub/Sub: Go Cloud Pub/Sub (GCP Pub/Sub or in‑memory for dev)
• Blob: Go Cloud Blob (GCS, file, or in‑memory)

1. Prerequisites
   • Go (latest stable)
   • Algolia application (you can use placeholder values to boot the server)
2. Copy .env and adjust if needed (defaults are present in the repo).
3. Run the API server:
   • go run ./cmd/server
4. Open GraphQL Playground (if enabled):
   • http://localhost:4000/api/docs
   • GraphQL endpoint: http://localhost:4000/api/query

Tip: To start without external services, use in‑memory URIs for Docstore, Pub/Sub and Blob. Algolia env vars must be non‑empty for the server to start (fake strings work for booting).

The server reads environment variables (from your shell and .env). Common setups:

• Minimal in‑memory/dev configuration

# Docstore (in‑memory)
DOCSTORE_TWEETS=mem://tweet/id
DOCSTORE_USERS=mem://users/id
DOCSTORE_CONTACT_US=mem://contact/id

# Pub/Sub (in‑memory)
TOPIC_CAPTURE=mem://captureRequest

# Blob (local filesystem or in‑memory)
BLOB_BUCKET=file:///tmp/capture
# BLOB_BUCKET=mem://bucket

# GraphQL
GRAPHQL_ENABLE_PLAYGROUND=true
PORT=4000

# Twitter API (required for capture to work)
TWITTER_ACCESS_SECRET=
TWITTER_ACCESS_TOKEN=
TWITTER_CONSUMER_KEY=
TWITTER_CONSUMER_SECRET=

# Algolia (required to start the server; fake strings are OK for local boot)
ALGOLIA_SECRET=your_secret
ALGOLIA_CLIENT_ID=your_client_id
ALGOLIA_INDEX=tweets-LOCAL

• Firestore (local emulator) example

If you prefer Firestore via Go Cloud Docstore:

FIRESTORE_EMULATOR_HOST=localhost:8080
DOCSTORE_TWEETS=firestore://projects/local/databases/(default)/documents/dev-tweets?name_field=id
DOCSTORE_USERS=firestore://projects/local/databases/(default)/documents/dev-authors?name_field=id
DOCSTORE_CONTACT_US=firestore://projects/local/databases/(default)/documents/dev-contact?name_field=id

Note: MongoDB settings previously listed were removed since this codebase currently registers Firestore and in‑memory Docstore drivers. There is no MONGO_SERVER_URL usage in the code.

• Playground (when GRAPHQL_ENABLE_PLAYGROUND=true): GET /api/docs
• Endpoint: ANY /api/query
• Schema: see schema.graphql

Example operations:

• Query a tweet by ID: query { tweet(id: "123") { id fullText author { userName } } }
• Search: query { search(input: { term: "golang" }, size: 10) { id fullText } }
• Capture: mutation { capture(url: "https://twitter.com/.../status/123") { id captureURL } }

• Build and run locally without pushing:
  • make generate
  • CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o cmd/server/tmp/app cmd/server/main.go
  • docker build -t capturetweet-server:local cmd/server
  • docker run -p 4000:4000 --env-file .env capturetweet-server:local

The provided Makefile also includes a docker-backend target that builds and pushes to an example registry; update it to your registry if needed.

• Run tests: go test ./...
• Code generation (gqlgen mocks, etc.): make generate

• Golang Tutorial

• Create a skeleton project
• Add GraphQL support
• Tweet Service
  • CRUD for tweet service
  • Use Algolia for search
  • Store user additional data in a different collection
• Async capture
  • Pub/Sub support
  • Capture and update collection
• New UI design
• Apollo client support
• Capture tweet
  • Real time image update with Firebase JS
  • GraphQL subscribe
  • Report capture
• Search tweet
• Contact us

This project is licensed under the MIT License – see the LICENSE file for details.