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

Introduction

Hey there, fellow Go enthusiast! Ready to supercharge your email marketing game? Let's dive into building a SendFox API integration using Go. SendFox is a nifty tool for managing your email lists and campaigns, and with Go's power, we'll make it sing.

Prerequisites

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

• Go installed (you're a Gopher, right?)
• A SendFox API key (grab one from your SendFox account)
• Your favorite code editor

Setting up the project

Let's kick things off:

mkdir sendfox-go
cd sendfox-go
go mod init github.com/yourusername/sendfox-go

Now, let's grab the HTTP client we'll need:

go get github.com/go-resty/resty/v2

Authenticating with SendFox API

First things first, let's keep that API key safe:

package main

import (
    "os"
    "github.com/go-resty/resty/v2"
)

const baseURL = "https://api.sendfox.com/v1"

func main() {
    apiKey := os.Getenv("SENDFOX_API_KEY")
    client := resty.New().
        SetBaseURL(baseURL).
        SetHeader("Authorization", "Bearer "+apiKey)
}

Implementing core functionalities

Creating a contact

Let's add some folks to your list:

func createContact(client *resty.Client, email string) error {
    _, err := client.R().
        SetBody(map[string]string{"email": email}).
        Post("/contacts")
    return err
}

Retrieving contact lists

Gotta know who's on your list, right?

func getContactLists(client *resty.Client) ([]map[string]interface{}, error) {
    var result []map[string]interface{}
    _, err := client.R().
        SetResult(&result).
        Get("/lists")
    return result, err
}

Sending an email campaign

Time to spread the word:

func sendCampaign(client *resty.Client, listID, subject, body string) error {
    _, err := client.R().
        SetBody(map[string]string{
            "list_id": listID,
            "subject": subject,
            "body":    body,
        }).
        Post("/campaigns")
    return err
}

Error handling and rate limiting

Let's be nice to the API and handle those pesky errors:

func retryableRequest(client *resty.Client, req func() error) error {
    maxRetries := 3
    for i := 0; i < maxRetries; i++ {
        err := req()
        if err == nil {
            return nil
        }
        time.Sleep(time.Second * time.Duration(i+1))
    }
    return fmt.Errorf("max retries reached")
}

Testing the integration

Don't forget to test! Here's a quick example:

func TestCreateContact(t *testing.T) {
    client := setupTestClient()
    err := createContact(client, "[email protected]")
    assert.NoError(t, err)
}

Best practices and optimization

To keep things speedy, let's cache those responses:

var listCache struct {
    sync.RWMutex
    lists []map[string]interface{}
}

func getCachedLists(client *resty.Client) ([]map[string]interface{}, error) {
    listCache.RLock()
    if listCache.lists != nil {
        defer listCache.RUnlock()
        return listCache.lists, nil
    }
    listCache.RUnlock()

    listCache.Lock()
    defer listCache.Unlock()
    lists, err := getContactLists(client)
    if err == nil {
        listCache.lists = lists
    }
    return lists, err
}

Conclusion

And there you have it! You've just built a solid SendFox API integration in Go. Remember, this is just the beginning – there's always room to expand and improve. Keep coding, keep learning, and most importantly, have fun with it!

For the complete code and more examples, check out the GitHub repository.

Now go forth and conquer those email campaigns with your shiny new Go integration!