goqueue

A distributed task queue written in Go, backed by Redis.

I built this to understand how background job processing works under the hood — no frameworks, just Go's standard library, goroutines, and Redis data structures.

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What it does

You submit a job (via CLI or HTTP), it gets queued in Redis, and a pool of goroutine workers picks it up and processes it. If a job fails, it retries automatically with exponential backoff. Jobs have three priority levels — high priority jobs always get processed before medium or low.

you submit a job
      │
      ▼
Redis queue (high / medium / low)
      │
      ▼
goroutine worker picks it up
      │
      ├── success → mark done
      └── failure → retry with backoff → mark failed after max retries

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Tech stack

• Go — core language, no web framework used
• Redis — message broker and job store
• go-redis/v9 — Redis client
• cobra — CLI framework (same one kubectl uses)
• Docker + docker-compose — containerized deployment

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Project structure

goqueue/
├── main.go              entry point
├── config/              env-based configuration
├── queue/               Job struct, Priority and Status types
├── store/               all Redis operations
├── worker/              goroutine pool and job processing logic
├── api/                 REST API server (net/http)
├── cmd/                 CLI commands (server, submit, status, stats)
├── Dockerfile           multi-stage build
└── docker-compose.yml   Redis + goqueue wired together

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How Redis is used

This was one of the more interesting design decisions. I use four Redis data structures:

Key	Type	Purpose
goqueue:queue:high	LIST	high priority job IDs waiting to be processed
goqueue:queue:medium	LIST	medium priority job IDs
goqueue:queue:low	LIST	low priority job IDs
goqueue:job:<id>	HASH	full job metadata stored as JSON
goqueue:jobs	SET	registry of all job IDs ever created
goqueue:stats	HASH	counters: enqueued, completed, failed, etc.

Workers use BRPOP on all three queues in order — [high, medium, low]. Redis checks the high queue first and only moves to medium if high is empty. Priority is handled entirely by Redis, no extra logic needed.

LPUSH + BRPOP gives a FIFO queue within the same priority level. New jobs are pushed to the left, workers pop from the right.

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Getting started

Option 1 — Docker (easiest)

git clone https://github.com/Fakekeymaster/goqueue.git
cd goqueue
make docker-up

This starts Redis and goqueue together. The API is available at localhost:8080.

Option 2 — Run locally

You need Go 1.22+ and Redis running on localhost:6379.

git clone https://github.com/Fakekeymaster/goqueue.git
cd goqueue
make build
make run

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CLI usage

Start the server

./goqueue server --workers 5 --port 8080

Submit a job

./goqueue submit --name "send-welcome" --type email_send --priority high
./goqueue submit --name "resize-img"   --type image_resize --priority medium
./goqueue submit --name "cleanup"      --type log_cleanup --priority low

Output:

Job submitted successfully
  ID:       3f2a1b4c-...
  Name:     send-welcome
  Type:     email_send
  Priority: 10
  Status:   pending

Check job status

./goqueue status --id <job-id>

Output:

Job details
────────────────────────────────
  ID:         3f2a1b4c-...
  Name:       send-welcome
  Type:       email_send
  Priority:   10
  Status:     done
  Retries:    0 / 3
  Created:    2026-04-26T19:47:22Z
  Updated:    2026-04-26T19:47:23Z

View queue metrics

./goqueue stats

Output:

Queue metrics
────────────────────────────────
  completed:             5
  enqueued:              5
  failed:                0
  pending:               0
  queue_high:            0
  queue_low:             0
  queue_medium:          0
  running:               0
  total_jobs:            5

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REST API

The CLI is just a wrapper around the HTTP API. You can use curl directly too.

Method	Endpoint	Description
GET	/health	health check
POST	/jobs	submit a job
GET	/jobs	list all jobs
GET	/jobs/{id}	get job by ID
GET	/stats	queue metrics

# submit a job via curl
curl -X POST http://localhost:8080/jobs \
  -H "Content-Type: application/json" \
  -d '{"name":"my-job","type":"email_send","priority":"high"}'

# check stats
curl http://localhost:8080/stats

---

Job lifecycle

pending → running → done
              │
              └── retrying → pending  (backoff: 2s, 4s, 8s...)
                      │
                      └── failed  (after max retries)

Retry backoff is exponential — 2^attempt seconds, capped at 60s. So if a job fails three times, it waits 2s, then 4s, then 8s before each retry. After MAX_RETRIES attempts it's marked permanently failed.

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Configuration

Everything is configurable via environment variables:

Variable	Default	Description
REDIS_ADDR	localhost:6379	Redis address
REDIS_PASS	""	Redis password
REDIS_DB	0	Redis database number
API_PORT	8080	REST API port
WORKER_COUNT	5	number of goroutine workers
MAX_RETRIES	3	max retry attempts per job

CLI flags override environment variables:

./goqueue server --workers 10 --port 9000

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Adding your own job handlers

Right now the default handler just logs and sleeps. To add real handlers, use HandlerMap in worker/worker.go:

handlers := worker.HandlerMap{
    "email_send":   handleEmail,
    "image_resize": handleImageResize,
    "log_cleanup":  handleLogCleanup,
}

pool := worker.NewPool(cfg.WorkerCount, store, handlers.Dispatch)

Each handler is just a function:

func handleEmail(ctx context.Context, job *queue.Job) error {
    // your logic here
    // return error to trigger retry
    // return nil for success
}

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Makefile targets

make build       # compile binary
make run         # build + start server
make test        # run tests with race detector
make lint        # go vet
make clean       # remove binary
make docker-up   # start Redis + goqueue via docker-compose
make docker-down # stop containers and remove volumes
make submit      # submit a sample job (server must be running)
make stats       # show live stats (server must be running)
make help        # list all targets

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What I learned building this

• How BRPOP with ordered keys gives you priority queuing for free — no sorting needed
• Why goroutines are so much cheaper than threads — the pool runs 5–100 workers with negligible overhead
• How multi-stage Docker builds cut image size from ~800MB to ~20MB
• The repository pattern — keeping all Redis logic in one place makes it easy to swap backends
• Graceful shutdown — cancelling a context propagates to every goroutine that uses it

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License

MIT