Go SDK for Homebrew Formulae API

A Go client library for the Homebrew Formulae API. No authentication required — the API is public and read-only. Includes a production-ready transport with retries, adaptive rate limiting, concurrency control, structured logging, and optional OpenTelemetry tracing.

Quick Start

go get github.com/deploymenttheory/go-sdk-brew

import (
    "context"
    "fmt"
    "log"

    brew "github.com/deploymenttheory/go-sdk-brew/brew"
    "github.com/deploymenttheory/go-sdk-brew/brew/services/analytics"
)

func main() {
    client, err := brew.NewClient("") // defaults to https://formulae.brew.sh
    if err != nil {
        log.Fatal(err)
    }

    ctx := context.Background()

    // List all formulae
    formulae, _, err := client.Formulae.List(ctx)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("Total formulae: %d\n", len(formulae))

    // Get a formula by name
    wget, _, err := client.Formulae.GetByName(ctx, "wget")
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("wget %s: %s\n", wget.Versions.Stable, wget.Desc)

    // Install analytics for the last 30 days
    stats, _, err := client.Analytics.ListByCategory(ctx, analytics.CategoryInstall, analytics.Period30d)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("Top formula: %s (%s installs)\n", stats.Items[0].Formula, stats.Items[0].Count)
}

API Coverage

The SDK covers all endpoints of the Homebrew Formulae API:

Formulae (client.Formulae)

Method	Endpoint	Description
List(ctx)	GET /api/formula.json	All Homebrew formulae
GetByName(ctx, name)	GET /api/formula/{name}.json	Single formula by name

Casks (client.Casks)

Method	Endpoint	Description
List(ctx)	GET /api/cask.json	All Homebrew casks
GetByName(ctx, name)	GET /api/cask/{name}.json	Single cask by name

Analytics (client.Analytics)

Method	Endpoint	Description
ListByCategory(ctx, category, period)	GET /api/analytics/{category}/{period}.json	Ranked install analytics (items array)
ListCoreByCategory(ctx, category, period)	GET /api/analytics/{category}/homebrew-core/{period}.json	homebrew-core analytics (formulae map)
ListCaskInstalls(ctx, period)	GET /api/analytics/cask-install/homebrew-cask/{period}.json	Cask install analytics (formulae map)

Analytics categories: analytics.CategoryInstall, analytics.CategoryInstallOnRequest, analytics.CategoryBuildError

Analytics periods: analytics.Period30d, analytics.Period90d, analytics.Period365d

Examples

The examples directory contains a working example demonstrating all three services:

• examples/basic/main.go — Lists formulae, gets wget, lists casks, gets iterm2, and fetches install analytics

Configuration Options

Creating a client

import brew "github.com/deploymenttheory/go-sdk-brew/brew"

// Default base URL (https://formulae.brew.sh)
client, err := brew.NewClient("")

// Custom base URL
client, err := brew.NewClient("https://formulae.brew.sh")

// With options
client, err := brew.NewClient("",
    brew.WithTimeout(30*time.Second),
    brew.WithRetryCount(3),
    brew.WithLogger(logger),
)

Available options

All configuration is passed via functional options to NewClient.

Basic Configuration

brew.WithBaseURL("https://formulae.brew.sh")          // Override base URL
brew.WithTimeout(30*time.Second)                       // Request timeout (default: 30s)
brew.WithRetryCount(3)                                 // Retry attempts on transient errors (default: 3)
brew.WithRetryWaitTime(2*time.Second)                  // Initial retry wait (default: 2s)
brew.WithRetryMaxWaitTime(30*time.Second)              // Max retry wait with backoff (default: 30s)
brew.WithTotalRetryDuration(2*time.Minute)             // Total retry budget across all attempts

TLS / Security

brew.WithTLSClientConfig(tlsConfig)                    // Custom *tls.Config
brew.WithInsecureSkipVerify()                          // Skip TLS verification (dev only)

Network

brew.WithProxy("http://proxy.example.com:8080")        // HTTP/HTTPS/SOCKS5 proxy
brew.WithTransport(customTransport)                    // Custom net/http Transport

Headers

brew.WithUserAgent("MyApp/1.0")                        // Set User-Agent
brew.WithGlobalHeader("X-Custom", "value")             // Add a single global header
brew.WithGlobalHeaders(map[string]string{...})         // Add multiple global headers

Observability

brew.WithLogger(zapLogger)                             // Structured logging with go.uber.org/zap
brew.WithDebug()                                       // Verbose request/response logging (dev only)

OpenTelemetry tracing is configured at the transport level via brew.WithTransport. Wrap your existing transport with otelhttp.NewTransport before passing it in, or use brew.WithOpenTelemetry if enabled in your build.

Concurrency & Rate Limiting

brew.WithMaxConcurrentRequests(10)                     // Max parallel in-flight requests (default: 10)
brew.WithMandatoryRequestDelay(50*time.Millisecond)    // Fixed delay between requests

The transport also applies an EMA-based adaptive delay automatically when API response times degrade.

Example: Production Configuration

import (
    "time"

    "go.uber.org/zap"
    brew "github.com/deploymenttheory/go-sdk-brew/brew"
)

logger, _ := zap.NewProduction()

client, err := brew.NewClient("",
    brew.WithTimeout(30*time.Second),
    brew.WithRetryCount(3),
    brew.WithRetryWaitTime(2*time.Second),
    brew.WithRetryMaxWaitTime(30*time.Second),
    brew.WithMaxConcurrentRequests(10),
    brew.WithLogger(logger),
    brew.WithUserAgent("my-app/1.0"),
)

Response Shape

All service methods return (result, *resty.Response, error):

formula, resp, err := client.Formulae.GetByName(ctx, "wget")
if err != nil {
    // Handle error — includes API errors (404, 500, etc.) and network errors
}

fmt.Println(resp.StatusCode()) // 200
fmt.Println(formula.Name)      // "wget"
fmt.Println(formula.Versions.Stable)
fmt.Println(formula.Dependencies)

Analytics response shapes

The three analytics endpoints return different Go types because the Homebrew API uses different JSON shapes for each:

// General analytics: ranked items array
result, _, _ := client.Analytics.ListByCategory(ctx, analytics.CategoryInstall, analytics.Period30d)
for _, item := range result.Items {
    fmt.Printf("#%d %s — %s installs (%s%%)\n", item.Number, item.Formula, item.Count, item.Percent)
}

// homebrew-core: formulae map (formula name → []CoreFormulaItem)
core, _, _ := client.Analytics.ListCoreByCategory(ctx, analytics.CategoryInstall, analytics.Period30d)
for name, entries := range core.Formulae {
    fmt.Printf("%s: %s installs\n", name, entries[0].Count)
}

// Cask installs: formulae map (cask token → []CaskInstallItem)
casks, _, _ := client.Analytics.ListCaskInstalls(ctx, analytics.Period30d)
for token, entries := range casks.Formulae {
    fmt.Printf("%s: %s installs\n", token, entries[0].Count)
}

Testing

# Unit tests (no network required — fixture-based mocks)
go test ./brew/services/...

# Acceptance tests (hits live https://formulae.brew.sh)
go test -v ./brew/acceptance/... -timeout 120s

# Optional env vars for acceptance tests
BREW_BASE_URL=https://formulae.brew.sh   # override API base URL
BREW_REQUEST_TIMEOUT=30s                 # per-test context timeout
BREW_VERBOSE=true                        # enable detailed logging

Documentation

• Homebrew Formulae API Reference
• GoDoc

Contributing

Contributions are welcome. Please read our Contributing Guidelines before submitting pull requests.

License

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

Support

• Issues: GitHub Issues
• Homebrew API docs: formulae.brew.sh/docs/api

Disclaimer

This is a community SDK and is not affiliated with or endorsed by the Homebrew project.