Spooled Go SDK

Official Go SDK for Spooled Cloud — a modern, scalable job queue and task scheduler.

Live Demo (SpriteForge) • Documentation

Features

• Idiomatic Go API with functional options pattern
• Full API Coverage — Access all Spooled API endpoints
• Type Safety — Strongly typed requests and responses
• Context Support — Full context.Context propagation
• Automatic Retries — Exponential backoff with jitter
• Circuit Breaker — Fault tolerance for unreliable networks
• Worker Runtime — Process jobs with concurrent workers
• Real-time Events — WebSocket and SSE support
• gRPC Support — High-performance streaming client
• Workflow DAGs — Complex job dependencies
• Automatic JWT Refresh — Single-flight token refresh

Installation

go get github.com/spooled-cloud/spooled-sdk-go

Requirements: Go 1.25 or later

Quick Start

Create a Job

package main

import (
    "context"
    "fmt"
    "log"

    "github.com/spooled-cloud/spooled-sdk-go/spooled"
    "github.com/spooled-cloud/spooled-sdk-go/spooled/resources"
)

func main() {
    // Create client
    client, err := spooled.NewClient(
        spooled.WithAPIKey("sp_live_your_api_key"),
        // For self-hosted: spooled.WithBaseURL("https://your-server.com"),
    )
    if err != nil {
        log.Fatal(err)
    }

    ctx := context.Background()

    // Create a job
    priority := 5
    maxRetries := 3
    result, err := client.Jobs().Create(ctx, &resources.CreateJobRequest{
        QueueName: "email-notifications",
        Payload: map[string]any{
            "to":      "user@example.com",
            "subject": "Welcome!",
            "body":    "Thanks for signing up.",
        },
        Priority:   &priority,
        MaxRetries: &maxRetries,
    })
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("Created job: %s\n", result.ID)

    // Get job status
    job, err := client.Jobs().Get(ctx, result.ID)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("Status: %s\n", job.Status)
}

Process Jobs with a Worker

package main

import (
    "context"
    "fmt"
    "log"
    "os"
    "os/signal"
    "syscall"

    "github.com/spooled-cloud/spooled-sdk-go/spooled"
    "github.com/spooled-cloud/spooled-sdk-go/spooled/worker"
)

func main() {
    client, err := spooled.NewClient(
        spooled.WithAPIKey("sp_live_your_api_key"),
    )
    if err != nil {
        log.Fatal(err)
    }

    // Create worker
    w := worker.NewWorker(client.Jobs(), client.Workers(), worker.Options{
        QueueName:   "email-notifications",
        Concurrency: 10,
    })

    // Register job handler
    w.Process(func(ctx *worker.JobContext) (map[string]any, error) {
        fmt.Printf("Processing job %s\n", ctx.JobID)
        
        // Access payload
        to := ctx.Payload["to"].(string)
        subject := ctx.Payload["subject"].(string)
        
        // Do your work here
        fmt.Printf("Sending email to %s: %s\n", to, subject)
        
        // Report progress
        ctx.Progress(50, "Email sent")
        
        return map[string]any{"sent": true}, nil
    })

    // Handle events
    w.OnEvent(func(event worker.Event) {
        fmt.Printf("Event: %s\n", event.Type)
    })

    // Start worker
    ctx, cancel := context.WithCancel(context.Background())
    if err := w.Start(ctx); err != nil {
        log.Fatal(err)
    }

    // Graceful shutdown
    sigCh := make(chan os.Signal, 1)
    signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
    <-sigCh

    cancel()
    w.Stop()
}

Real-world examples (beginner friendly)

If you want 5 copy/paste “real life” setups (Stripe → jobs, GitHub Actions → jobs, cron schedules, CSV import, website signup), see:

• https://github.com/spooled-cloud/spooled-backend/blob/main/docs/guides/real-world-examples.md

Documentation

Guide	Description
Getting Started	Installation, setup, and first job
Configuration	All configuration options
Workers	Job processing with Worker
Workflows	Building DAGs with job dependencies
gRPC	High-performance streaming
Real-time Events	WebSocket and SSE
Error Handling	Typed errors and retries

Examples

See the examples/ directory for runnable code:

Example	Description
quick-start/	Basic SDK usage
worker/	Processing jobs with Worker
workflow/	Complex workflows with dependencies
grpc/	High-performance gRPC streaming
realtime/	Real-time event streaming
schedules/	Cron schedules
webhooks/	Webhook configuration
api-keys/	API key management
bulk-operations/	Bulk job operations
error-handling/	Error handling patterns

Run any example with:

API_KEY=sp_live_... go run examples/quick-start/main.go

Configuration

Client Options

client, err := spooled.NewClient(
    // Authentication (required - one of these)
    spooled.WithAPIKey("sp_live_..."),
    spooled.WithAccessToken("eyJ..."),
    
    // Endpoints (optional)
    spooled.WithBaseURL("https://api.spooled.cloud"),
    spooled.WithWSURL("wss://api.spooled.cloud/api/v1/ws"),
    spooled.WithGRPCAddress("grpc.spooled.cloud:443"),
    
    // Timeouts (optional)
    spooled.WithTimeout(30 * time.Second),
    
    // Retries (optional)
    spooled.WithRetryConfig(spooled.RetryConfig{
        MaxRetries: 3,
        BaseDelay:  100 * time.Millisecond,
        MaxDelay:   5 * time.Second,
    }),
    
    // Circuit breaker (optional)
    spooled.WithCircuitBreaker(spooled.CircuitBreakerConfig{
        Enabled:          true,
        FailureThreshold: 5,
        Timeout:          30 * time.Second,
    }),
    
    // Debug logging (optional)
    spooled.WithDebug(true),
)

Environment Variables

SPOOLED_API_KEY=sp_live_...
SPOOLED_BASE_URL=https://api.spooled.cloud
SPOOLED_GRPC_ADDRESS=grpc.spooled.cloud:443

Core Concepts

Jobs

Jobs are units of work with payloads, priorities, and retry policies:

priority := 5
maxRetries := 3
timeout := 300
scheduledAt := time.Now().Add(time.Hour)

result, err := client.Jobs().Create(ctx, &resources.CreateJobRequest{
    QueueName:      "my-queue",
    Payload:        map[string]any{"data": "value"},
    Priority:       &priority,        // -100 to 100
    MaxRetries:     &maxRetries,
    TimeoutSeconds: &timeout,
    ScheduledAt:    &scheduledAt,
    IdempotencyKey: ptr("unique-key"),
})

// List jobs
jobs, err := client.Jobs().List(ctx, &resources.ListJobsParams{
    QueueName: ptr("my-queue"),
    Status:    ptr(resources.JobStatusPending),
    Tag:       ptr("billing"), // Optional: filter by a single tag
    Limit:     ptr(10),
})

// Cancel a job
err = client.Jobs().Cancel(ctx, jobID)

Workers

Process jobs with the built-in worker runtime:

w := worker.NewWorker(client.Jobs(), client.Workers(), worker.Options{
    QueueName:         "my-queue",
    WorkerID:          os.Getenv("HOSTNAME"), // Stable identity, see below
    Concurrency:       10,              // Max concurrent jobs
    PollInterval:      time.Second,     // Polling frequency
    LeaseDuration:     30,              // Lease duration in seconds
    HeartbeatFraction: 0.5,             // Heartbeat at 50% of lease
    ShutdownTimeout:   30 * time.Second,
})

w.Process(func(ctx *worker.JobContext) (map[string]any, error) {
    // ctx.Context - Go context with cancellation
    // ctx.JobID - Unique job ID
    // ctx.QueueName - Queue name
    // ctx.Payload - Job payload
    // ctx.RetryCount - Current retry attempt
    // ctx.MaxRetries - Maximum retries
    // ctx.Progress(percent, message) - Report progress
    // ctx.Log(level, message, meta) - Log messages
    
    return map[string]any{"result": "success"}, nil
})

// Event handlers
w.OnEvent(func(event worker.Event) {
    switch event.Type {
    case worker.EventJobCompleted:
        data := event.Data.(worker.JobCompletedData)
        fmt.Printf("Job %s completed in %v\n", data.JobID, data.Duration)
    case worker.EventJobFailed:
        data := event.Data.(worker.JobFailedData)
        fmt.Printf("Job %s failed: %v (will retry: %t)\n", data.JobID, data.Error, data.WillRetry)
    case worker.EventJobLeaseLost:
        data := event.Data.(worker.JobLeaseLostData)
        fmt.Printf("Job %s lost lease %s during %s: %v\n", data.JobID, data.LeaseID, data.Operation, data.Error)
    }
})

// The worker automatically echoes the claim's LeaseID on heartbeat and settlement.
// A stale lease cancels that handler context and emits EventJobLeaseLost.
ctx := context.Background()
w.Start(ctx)

// Graceful shutdown
w.Stop()

WorkerID is optional but worth setting. It must be 1-128 characters from [A-Za-z0-9._-], and keeping it the same across restarts makes registration an upsert, so the process reclaims one worker row. Leave it empty and the server mints a fresh UUID on every Start, which leaves the previous row occupying your plan's worker cap until the stale-worker reaper clears it (roughly two minutes) - long enough for a crash-looping worker on a tight plan to hit 429 QUOTA_EXCEEDED on its own registrations. Re-registering an ID your organization already owns costs nothing against the cap; an ID owned by another organization is rejected with 409.

Workflows (DAGs)

Orchestrate multiple jobs with dependencies:

workflow, err := client.Workflows().Create(ctx, &resources.CreateWorkflowRequest{
    Name: "ETL Pipeline",
    Jobs: []resources.WorkflowJob{
        {
            Key:       "extract",
            QueueName: "etl",
            Payload:   map[string]any{"step": "extract"},
        },
        {
            Key:       "transform",
            QueueName: "etl",
            Payload:   map[string]any{"step": "transform"},
            DependsOn: []string{"extract"},
        },
        {
            Key:       "load",
            QueueName: "etl",
            Payload:   map[string]any{"step": "load"},
            DependsOn: []string{"transform"},
        },
    },
})

// Get workflow status
wf, err := client.Workflows().Get(ctx, workflow.WorkflowID)
fmt.Printf("Status: %s\n", wf.Status)

Schedules

Run jobs on a cron schedule:

schedule, err := client.Schedules().Create(ctx, &resources.CreateScheduleRequest{
    Name:           "Daily Report",
    CronExpression: "0 9 * * *",       // 9 AM daily (5-field cron)
    Timezone:       ptr("America/New_York"),
    QueueName:      "reports",
    PayloadTemplate: map[string]any{"type": "daily"},
})

fmt.Printf("Next run: %v\n", schedule.NextRunAt)

// Pause/resume
client.Schedules().Pause(ctx, schedule.ID)
client.Schedules().Resume(ctx, schedule.ID)

// Trigger immediately
client.Schedules().Trigger(ctx, schedule.ID)

Queues

Manage queues and view statistics:

// List queues
queues, err := client.Queues().List(ctx)

// Get queue stats
stats, err := client.Queues().GetStats(ctx, "my-queue")
fmt.Printf("Pending: %d, Processing: %d\n", stats.Pending, stats.Processing)

// Pause/resume queue
client.Queues().Pause(ctx, "my-queue", nil)
client.Queues().Resume(ctx, "my-queue")

// Purge all pending jobs
client.Queues().Purge(ctx, "my-queue")

Real-time Events

Subscribe to real-time job events via WebSocket or SSE:

// WebSocket client
ws := realtime.NewWebSocketClient(realtime.ConnectionOptions{
    WSURL:  "wss://api.spooled.cloud/api/v1/ws",
    Token:  "your-jwt-token",
    APIKey: "sp_live_...",
})

ws.OnJobEvent(realtime.EventJobCompleted, func(event *realtime.JobEvent) {
    fmt.Printf("Job completed: %s\n", event.JobID)
})

ws.OnStateChange(func(state realtime.ConnectionState) {
    fmt.Printf("Connection state: %s\n", state)
})

ws.Connect()
ws.Subscribe(realtime.SubscriptionFilter{QueueName: "my-queue"})

// SSE client (unidirectional)
sse := realtime.NewSSEClient(realtime.ConnectionOptions{
    BaseURL: "https://api.spooled.cloud",
    APIKey:  "sp_live_...",
})

sse.OnEvent(func(event *realtime.Event) {
    fmt.Printf("Event: %s\n", event.Type)
})

sse.ConnectWithFilter(&realtime.SubscriptionFilter{
    QueueName: "my-queue",
})

gRPC (High Performance)

Use gRPC for high-throughput scenarios:

import "github.com/spooled-cloud/spooled-sdk-go/spooled/grpc"

client, err := grpc.NewClient(grpc.ClientOptions{
    Address: "grpc.spooled.cloud:443",
    APIKey:  "sp_live_...",
})
defer client.Close()

// Enqueue a job
resp, err := client.Enqueue(ctx, &grpc.EnqueueRequest{
    QueueName: "high-throughput",
    Payload:   map[string]any{"data": "value"},
    Priority:  5,
})
fmt.Printf("Job ID: %s\n", resp.JobID)

// Dequeue jobs
jobs, err := client.Dequeue(ctx, &grpc.DequeueRequest{
    QueueName: "high-throughput",
    WorkerID:  "worker-1",
    BatchSize: 10,
})

// Echo each dequeued job's LeaseID on settlement so stale executions are fenced.
for _, job := range jobs.Jobs {
    // Process job...
    err = client.Complete(ctx, &grpc.CompleteRequest{
        JobID: job.ID, WorkerID: "worker-1", LeaseID: job.LeaseID,
    })
}

// Stream jobs (server-side streaming)
stream, err := client.StreamJobs(ctx, "high-throughput", "worker-1")
for {
    job, err := stream.Recv()
    if err == io.EOF {
        break
    }
    // Process job...
}

Webhooks

Configure outgoing webhooks for job events:

// Create webhook. The secret signs every delivery with an X-Spooled-Signature header.
webhook, err := client.Webhooks().Create(ctx, &resources.CreateOutgoingWebhookRequest{
    Name: "Job Notifications",
    URL:  "https://your-app.com/webhooks/spooled",
    Events: []resources.WebhookEvent{
        resources.WebhookEventJobCompleted,
        resources.WebhookEventJobFailed,
    },
    Secret: ptr("whsec_..."),
})

// Test webhook
client.Webhooks().Test(ctx, webhook.ID)

// List deliveries
deliveries, err := client.Webhooks().Deliveries(ctx, webhook.ID, nil)

Webhooks disable themselves. After 20 consecutive failed deliveries the server sets Enabled to false and LastStatus to "auto_disabled", and the webhook stops receiving events. LastStatus is one of "success", "failed" or "auto_disabled". Bring it back with an update:

if wh.LastStatus != nil && *wh.LastStatus == "auto_disabled" {
    // Re-enabling counts against the plan webhook cap, so it can fail with
    // 429 QUOTA_EXCEEDED.
    _, err = client.Webhooks().Update(ctx, wh.ID, &resources.UpdateOutgoingWebhookRequest{
        Enabled: ptr(true),
    })
}

FailureCount is the number of consecutive failed deliveries, counted once per delivery rather than once per retry attempt, so it is roughly five times smaller than a per-attempt count for the same real-world failures - recheck any alerting threshold you built on it. Any successful delivery resets it to 0, including a successful manual RetryDelivery.

Clearing the signing secret is destructive. The secret is three-state on update: leave Secret nil to keep it, set Secret to replace it, or set ClearSecret to remove it. Removing it means deliveries go out unsigned, with no X-Spooled-Signature header for your receiver to verify, and there is no way to recover the old value - set a new Secret to sign again.

// Keeps the current secret: Secret is nil, so the field is left out entirely.
_, err = client.Webhooks().Update(ctx, webhook.ID, &resources.UpdateOutgoingWebhookRequest{
    Events: &newEvents,
})

// Replaces the secret.
_, err = client.Webhooks().Update(ctx, webhook.ID, &resources.UpdateOutgoingWebhookRequest{
    Secret: ptr("whsec_rotated"),
})

// Removes the secret. Deliveries are unsigned from here on.
_, err = client.Webhooks().Update(ctx, webhook.ID, &resources.UpdateOutgoingWebhookRequest{
    ClearSecret: true,
})

Deliveries is not a durable audit log: only the newest 100 deliveries per webhook are readable, and rows are removed once they pass your plan's history retention window (1 day on free, 7 on starter, 30 on pro, 90 on enterprise). Copy anything you need to keep longer.

Organizations

Manage your organization and track usage:

// List organizations
orgs, err := client.Organizations().List(ctx)

// Get organization details
org, err := client.Organizations().Get(ctx, orgID)

// Get usage information
usage, err := client.Organizations().Usage(ctx, orgID)
fmt.Printf("Jobs today: %d/%d\n", usage.Usage.JobsToday.Current, *usage.Limits.MaxJobsPerDay)

API Keys

Manage API keys:

// List API keys
keys, err := client.APIKeys().List(ctx)

// Create new API key
key, err := client.APIKeys().Create(ctx, &resources.CreateAPIKeyRequest{
    Name: "Production Key",
})
fmt.Printf("Key: %s (save this, it won't be shown again)\n", key.Key)

// Revoke API key
client.APIKeys().Revoke(ctx, keyID)

Error Handling

The SDK provides typed errors for different failure scenarios:

import "github.com/spooled-cloud/spooled-sdk-go/spooled"

job, err := client.Jobs().Get(ctx, "invalid-id")
if err != nil {
    switch e := err.(type) {
    case *spooled.NotFoundError:
        fmt.Printf("Job not found: %s\n", e.Message)
    case *spooled.AuthenticationError:
        fmt.Printf("Invalid API key: %s\n", e.Message)
    case *spooled.RateLimitError:
        // 429 covers both per-second rate limiting and plan-quota errors.
        // A plan quota carries Code == "QUOTA_EXCEEDED" (with resource/current/limit/plan details).
        if e.Code == "QUOTA_EXCEEDED" {
            fmt.Printf("Plan quota exceeded: %s\n", e.Message)
        } else {
            fmt.Printf("Rate limited. Retry after: %v\n", e.Reset)
        }
    case *spooled.ValidationError:
        fmt.Printf("Invalid request: %v\n", e.Errors)
    default:
        fmt.Printf("Error: %v\n", err)
    }
}

// Check error types
if spooled.IsRetryableError(err) {
    // Safe to retry
}
if spooled.IsNetworkError(err) {
    // Network issue
}
if spooled.IsTimeoutError(err) {
    // Request timed out
}

Development

Using Make

# Build, lint, and test
make

# Run specific targets
make build          # Build the SDK
make test           # Run unit tests
make test-coverage  # Tests with coverage report
make lint           # Run linter
make fmt            # Format code
make examples       # Build all examples

# Integration tests (requires API_KEY)
API_KEY=sp_live_... make integration-test

# See all commands
make help

Testing

# Unit tests
go test ./...

# With race detection
go test -race ./...

# With coverage
go test -cover ./...

# Integration tests (requires API key)
API_KEY=sp_live_... go run scripts/test-local/main.go

# Full production test suite (all features)
API_KEY=sp_live_... \
ADMIN_KEY=your_admin_key \
BASE_URL=https://api.spooled.cloud \
GRPC_ADDRESS=grpc.spooled.cloud:443 \
SKIP_GRPC=0 \
SKIP_STRESS=0 \
go run scripts/test-local/main.go

Contributing

Contributions are welcome! Please see this repository's CONTRIBUTING.md.

License

Apache 2.0 - see LICENSE for details.

Support

• 📖 Documentation
• 🐛 Issue Tracker
• 📧 Email Support