Step by Step Guide to Building a CallRail API Integration in Go

Introduction

Hey there, fellow code wrangler! Ready to dive into the world of CallRail API integration with Go? Buckle up, because we're about to embark on a journey that'll have you pulling call data and creating tracking numbers like a pro. This guide assumes you're already familiar with Go and API basics, so we'll keep things snappy and focus on the good stuff.

Prerequisites

Before we jump in, make sure you've got:

• Go installed (you're a Go dev, right?)
• CallRail API credentials (if you don't have 'em, go grab 'em)
• Your favorite Go packages for HTTP requests and JSON handling

Setting up the project

Let's kick things off by setting up our project:

mkdir callrail-integration
cd callrail-integration
go mod init github.com/yourusername/callrail-integration

Easy peasy, right? Now we're ready to rock and roll.

Authentication

First things first, let's get that authentication sorted:

const apiKey = "your-api-key-here"

client := &http.Client{}

func createRequest(method, url string, body io.Reader) (*http.Request, error) {
    req, err := http.NewRequest(method, url, body)
    if err != nil {
        return nil, err
    }
    req.Header.Add("Authorization", "Token "+apiKey)
    req.Header.Add("Content-Type", "application/json")
    return req, nil
}

Boom! You've got a reusable client setup. Let's put it to work.

Making API requests

Time to fetch some data:

func getCalls() ([]Call, error) {
    req, err := createRequest("GET", "https://api.callrail.com/v3/a/ACCOUNT_ID/calls.json", nil)
    if err != nil {
        return nil, err
    }

    resp, err := client.Do(req)
    if err != nil {
        return nil, err
    }
    defer resp.Body.Close()

    // Parse response here
    // ...
}

Want to create a tracking number? No sweat:

func createTrackingNumber(data TrackingNumberData) (*TrackingNumber, error) {
    jsonData, err := json.Marshal(data)
    if err != nil {
        return nil, err
    }

    req, err := createRequest("POST", "https://api.callrail.com/v3/a/ACCOUNT_ID/numbers.json", bytes.NewBuffer(jsonData))
    if err != nil {
        return nil, err
    }

    // Send request and parse response
    // ...
}

Handling responses

Let's parse those JSON responses like a boss:

type CallResponse struct {
    Calls []Call `json:"calls"`
    // Add other fields as needed
}

// In your getCalls function:
var callResp CallResponse
err = json.NewDecoder(resp.Body).Decode(&callResp)
if err != nil {
    return nil, err
}

Don't forget to check for errors and handle them gracefully!

Implementing pagination

CallRail's API uses pagination, so let's handle it:

func getAllCalls() ([]Call, error) {
    var allCalls []Call
    page := 1

    for {
        calls, nextPage, err := getCallsPage(page)
        if err != nil {
            return nil, err
        }

        allCalls = append(allCalls, calls...)

        if nextPage == 0 {
            break
        }
        page = nextPage
    }

    return allCalls, nil
}

Rate limiting

Be a good API citizen and implement rate limiting:

import "golang.org/x/time/rate"

var limiter = rate.NewLimiter(rate.Limit(5), 1) // 5 requests per second

func makeRateLimitedRequest(req *http.Request) (*http.Response, error) {
    err := limiter.Wait(context.Background())
    if err != nil {
        return nil, err
    }
    return client.Do(req)
}

Webhooks

If you're using webhooks, set up an endpoint to receive them:

func webhookHandler(w http.ResponseWriter, r *http.Request) {
    // Parse and process webhook data
    // ...
}

func main() {
    http.HandleFunc("/webhook", webhookHandler)
    http.ListenAndServe(":8080", nil)
}

Testing

Don't forget to test your integration:

func TestGetCalls(t *testing.T) {
    // Mock HTTP client and test getCalls function
    // ...
}

Best practices

• Log errors and important events
• Cache frequently accessed data
• Keep your code modular and easy to maintain

Conclusion

And there you have it! You've just built a solid CallRail API integration in Go. Pat yourself on the back, grab a coffee, and start thinking about how you can take this integration to the next level. The sky's the limit!

Remember, the CallRail API is your oyster. Keep exploring, keep coding, and most importantly, have fun with it. Happy integrating!