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

Introduction

Hey there, fellow Go enthusiast! Ready to dive into the world of cloud storage integration? Today, we're going to walk through building a OneDrive API integration using Go. We'll be leveraging the awesome go-onedrive package to make our lives easier. Buckle up, because by the end of this guide, you'll be slinging files to and from OneDrive like a pro!

Prerequisites

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

• Go installed on your machine (I know you do, but just checking!)
• A Microsoft Azure account (we'll need this for app registration)
• A basic understanding of OAuth 2.0 (don't worry, we'll cover the essentials)

Setting up the project

Let's kick things off by creating a new Go project and grabbing the go-onedrive package:

mkdir onedrive-integration && cd onedrive-integration
go mod init onedrive-integration
go get github.com/goh-chunlin/go-onedrive/onedrive

Registering the application in Azure AD

Head over to the Azure Portal and register a new application. This is where you'll get your client ID and secret. Here's the quick rundown:

1. Navigate to Azure Active Directory > App registrations
2. Click "New registration"
3. Give your app a snazzy name
4. Set the redirect URI (use http://localhost:8080/callback for this guide)
5. After creation, grab your client ID from the overview page
6. Create a new client secret in the "Certificates & secrets" section

Jot down that client ID and secret – we'll need them soon!

Implementing OAuth 2.0 authentication

Now for the fun part – let's set up our OAuth flow:

package main

import (
    "context"
    "fmt"
    "log"
    "net/http"

    "github.com/goh-chunlin/go-onedrive/onedrive"
    "golang.org/x/oauth2"
)

var (
    clientID     = "YOUR_CLIENT_ID"
    clientSecret = "YOUR_CLIENT_SECRET"
    redirectURL  = "http://localhost:8080/callback"
    oauthConfig  = &oauth2.Config{
        ClientID:     clientID,
        ClientSecret: clientSecret,
        RedirectURL:  redirectURL,
        Scopes:       []string{"Files.ReadWrite.All", "offline_access"},
        Endpoint:     onedrive.Endpoint,
    }
)

func main() {
    http.HandleFunc("/", handleHome)
    http.HandleFunc("/callback", handleCallback)
    log.Fatal(http.ListenAndServe(":8080", nil))
}

func handleHome(w http.ResponseWriter, r *http.Request) {
    url := oauthConfig.AuthCodeURL("state", oauth2.AccessTypeOffline)
    http.Redirect(w, r, url, http.StatusFound)
}

func handleCallback(w http.ResponseWriter, r *http.Request) {
    code := r.URL.Query().Get("code")
    token, err := oauthConfig.Exchange(context.Background(), code)
    if err != nil {
        http.Error(w, "Failed to exchange token", http.StatusInternalServerError)
        return
    }
    // Use the token to create a OneDrive client
    client := onedrive.NewClient(oauthConfig.Client(context.Background(), token))
    // Now you can use the client to make API calls!
    fmt.Fprintf(w, "Authentication successful!")
}

Initializing the OneDrive client

With our OAuth flow set up, we can now create a OneDrive client:

client := onedrive.NewClient(oauthConfig.Client(context.Background(), token))

Basic operations with OneDrive API

Let's put our new client to work! Here are some common operations:

Listing files and folders

items, err := client.DriveItems.List(context.Background(), "")
if err != nil {
    log.Fatal(err)
}
for _, item := range items {
    fmt.Println(item.Name)
}

Uploading files

file, _ := os.Open("cute_cat.jpg")
defer file.Close()
item, err := client.DriveItems.Upload(context.Background(), "/Photos/cute_cat.jpg", file)
if err != nil {
    log.Fatal(err)
}
fmt.Printf("Uploaded: %s\n", item.Name)

Downloading files

content, err := client.DriveItems.Download(context.Background(), "FileID")
if err != nil {
    log.Fatal(err)
}
// Do something with the content

Creating folders

folder, err := client.DriveItems.CreateFolder(context.Background(), "New Folder", "")
if err != nil {
    log.Fatal(err)
}
fmt.Printf("Created folder: %s\n", folder.Name)

Error handling and best practices

When working with the OneDrive API, always:

• Check for errors after each API call
• Implement proper rate limiting to avoid hitting API quotas
• Use exponential backoff for retries on transient errors

Conclusion

And there you have it! You've just built a solid foundation for a OneDrive integration in Go. We've covered authentication, basic file operations, and even touched on some best practices. The go-onedrive package makes it a breeze to work with OneDrive, so don't be afraid to dive deeper into its documentation for more advanced features.

Remember, the cloud's the limit! Happy coding, and may your files always sync smoothly!

Sample code repository

For a complete working example, check out this GitHub repository: [link to your sample code repo]

Now go forth and conquer the cloud storage world with your newfound OneDrive powers!