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

Hey there, fellow Go enthusiast! Ready to dive into the world of document automation with PandaDoc? Let's roll up our sleeves and build an awesome API integration that'll make your document workflows smoother than a freshly waxed surfboard.

Introduction

PandaDoc's API is a powerhouse for document automation, e-signatures, and workflow management. We're going to harness this power in Go, creating an integration that'll make your documents dance to your tune.

Prerequisites

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

• A Go environment that's up and running
• PandaDoc API credentials (if you don't have 'em, hop over to PandaDoc's website and sign up)

Setting up the project

Let's kick things off by creating a new Go project:

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

Now, let's grab the dependencies we'll need:

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

Authentication

PandaDoc uses OAuth 2.0, so let's implement that flow:

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

func getAccessToken(clientID, clientSecret string) (string, error) {
    client := resty.New()
    resp, err := client.R().
        SetBasicAuth(clientID, clientSecret).
        SetFormData(map[string]string{
            "grant_type": "client_credentials",
        }).
        Post("https://api.pandadoc.com/oauth2/access_token")
    
    // Handle the response and extract the access token
    // ...
}

Core API Integration

Creating a document

Time to create your first document:

func createDocument(accessToken, name string, content []byte) (string, error) {
    client := resty.New()
    resp, err := client.R().
        SetAuthToken(accessToken).
        SetFileReader("file", "document.pdf", bytes.NewReader(content)).
        SetFormData(map[string]string{
            "name": name,
        }).
        Post("https://api.pandadoc.com/public/v1/documents")
    
    // Handle the response and extract the document ID
    // ...
}

Sending a document for signature

Got your document? Let's send it off for John Hancock's autograph:

func sendDocument(accessToken, documentID string, recipients []string) error {
    client := resty.New()
    _, err := client.R().
        SetAuthToken(accessToken).
        SetBody(map[string]interface{}{
            "recipients": recipients,
        }).
        Post(fmt.Sprintf("https://api.pandadoc.com/public/v1/documents/%s/send", documentID))
    
    return err
}

Checking document status

Let's see where that document's at in its journey:

func checkDocumentStatus(accessToken, documentID string) (string, error) {
    client := resty.New()
    resp, err := client.R().
        SetAuthToken(accessToken).
        Get(fmt.Sprintf("https://api.pandadoc.com/public/v1/documents/%s", documentID))
    
    // Handle the response and extract the status
    // ...
}

Downloading a completed document

Mission accomplished? Let's grab that signed document:

func downloadDocument(accessToken, documentID string) ([]byte, error) {
    client := resty.New()
    resp, err := client.R().
        SetAuthToken(accessToken).
        Get(fmt.Sprintf("https://api.pandadoc.com/public/v1/documents/%s/download", documentID))
    
    return resp.Body(), err
}

Error Handling and Logging

Don't forget to wrap these functions with proper error handling and logging. Your future self will thank you!

if err != nil {
    log.Printf("Error creating document: %v", err)
    return err
}

Testing

Unit tests are your friends. Here's a quick example:

func TestCreateDocument(t *testing.T) {
    // Mock the API response
    // Test the createDocument function
    // Assert the results
}

Best Practices

• Implement rate limiting to play nice with PandaDoc's API
• Keep your API keys and tokens secure (use environment variables, not hard-coded values)
• Consider using a circuit breaker for resilience

Advanced Features

Feeling adventurous? Try implementing webhook support or creating custom document templates. The sky's the limit!

Conclusion

And there you have it! You've just built a rock-solid PandaDoc API integration in Go. Remember, this is just the beginning. Keep exploring the API docs, and you'll find even more cool features to play with.

Now go forth and automate those documents like a boss! 🚀📄