How to Build a Backend for Golang?

introduction in this tutorial, you’ll learn how to build and test a complete backend for golang using back4app we will walk you through integrating essential back4app features—such as database management, security settings, user authentication, file storage, and cloud code—to create a secure, flexible, and scalable backend that works well with your go http server our focus will be on using back4app’s restful apis to connect to the database from our golang http client, rather than a dedicated parse sdk, so we can illustrate how to build easy to maintain handler functions for your new backend you will see how this approach lowers development complexity compared to setting up your own servers from scratch by relying on back4app’s real time queries, file storage, and user authentication systems, you’ll speed up your backend creation process by the end, you’ll know how to build a secure golang backend, schedule automated tasks, and integrate external webhooks you’ll be well prepared to enhance this foundation into a production ready application or add custom logic as needed prerequisites a back4app account sign up for free here https //www back4app com/ a new back4app project getting started with back4app https //www back4app com/docs/get started/new parse app go (golang) development environment make sure you have go installed on your machine you can find instructions in the go official docs https //go dev/ basic knowledge of go’s http package and restful apis familiarity with how to write a func handler, parse error messages, handle method post requests, and set up an http localhost server will help ensure you have these prerequisites in place before proceeding this setup will streamline your experience as you discover how to build a backend for golang using back4app step 1 – creating a new project on back4app and connecting why a new project? creating a new back4app project is your first step it’s where you’ll store data, configure file storage, schedule cloud functions, and add background tasks this backend project will anchor all subsequent steps log in to your back4app account click “new app” in your back4app dashboard name your app (for example, “golang backend tutorial”) once created, it will appear in your dashboard this application is now your back4app based backend connecting via rest apis back4app provides restful apis to create, update, and delete data in golang, we’ll use the http client from go’s standard library to communicate with these endpoints locate your application id and rest api key by going to the settings or security & keys section of your back4app app you’ll need these credentials in each request header we’ll illustrate this in the next steps when we connect to the database using method post, get, and other http requests step 2 – setting up the database creating a data model to store data in back4app, you define classes (tables) and columns (fields) for instance, let’s say we want a todo class you can create it manually in the back4app dashboard go to the database section in your app’s dashboard create a new class named “todo ” add columns such as title (string) and iscompleted (boolean) you can also let the system auto create columns by sending objects with new fields from your golang application creating a data model using the ai agent open the ai agent in your app dashboard describe your desired data model (e g , “please create a new todo class with a title field and iscompleted field ”) accept the suggested schema this handy feature saves time in designing your database schema reading and writing data using rest api (golang example) below is a basic example of how to create (method post) and fetch (method get) data using go’s http package assume you have your application id and rest api key as environment variables package main import ( "bytes" "encoding/json" "fmt" "io/ioutil" "log" "net/http" ) type todo struct { objectid string `json "objectid,omitempty"` title string `json "title,omitempty"` iscompleted bool `json "iscompleted,omitempty"` } func main() { // example create todo newtodo = todo{ title "buy groceries", iscompleted false, } created, err = createtodo(newtodo) if err != nil { log println("error creating todo ", err) } else { log println("created todo with id ", created objectid) } // example fetch todos todos, err = fetchalltodos() if err != nil { log println("error fetching todos ", err) } else { for , t = range todos { log println("fetched todo ", t title, t iscompleted) } } } // createtodo sends a post request to save a new record in the "todo" class func createtodo(todo todo) (todo, error) { // convert struct to json body, = json marshal(todo) // create http request req, err = http newrequest("post", "https //parseapi back4app com/classes/todo", bytes newbuffer(body)) if err != nil { return todo{}, err } // set necessary headers req header set("x parse application id", "your application id") req header set("x parse rest api key", "your rest api key") req header set("content type", "application/json") // execute the request client = \&http client{} resp, err = client do(req) if err != nil { return todo{}, err } defer resp body close() if resp statuscode != http statuscreated && resp statuscode != http statusok { bodybytes, = ioutil readall(resp body) return todo{}, fmt errorf("api error %s", string(bodybytes)) } // parse response var createdtodo todo if err = json newdecoder(resp body) decode(\&createdtodo); err != nil { return todo{}, err } return createdtodo, nil } // fetchalltodos retrieves all todo objects from back4app using get func fetchalltodos() (\[]todo, error) { req, err = http newrequest("get", "https //parseapi back4app com/classes/todo", nil) if err != nil { return nil, err } req header set("x parse application id", "your application id") req header set("x parse rest api key", "your rest api key") client = \&http client{} resp, err = client do(req) if err != nil { return nil, err } defer resp body close() if resp statuscode != http statusok { bodybytes, = ioutil readall(resp body) return nil, fmt errorf("api error %s", string(bodybytes)) } // parse response for "results" key var result struct { results \[]todo `json "results"` } if err = json newdecoder(resp body) decode(\&result); err != nil { return nil, err } return result results, nil } in these examples, we create an http client, add the necessary headers, and handle response codes along with error messages remember to replace your application id and your rest api key with the actual keys from your back4app project reading and writing data using graphql api back4app also provides a graphql endpoint at https //parseapi back4app com/graphql you can use a popular go graphql client library (like machine box graphql https //github com/machinebox/graphql ) to perform queries or mutations this can be a more structured approach than raw rest calls working with live queries (optional) if you’d like to see real time updates in your app, you can enable live queries in the back4app dashboard golang does not have an official parse live query library however, you can implement your own websocket connection to listen for live query updates from wss\ //your subdomain b4a io this feature is useful for collaborative apps requiring immediate data synchronization step 3 – applying security with acls and clps overview back4app provides access control lists (acls) and class level permissions (clps) to protect your data acls are defined on each object, while clps define overarching rules for an entire class class level permissions go to your app’s database view in back4app select a class (e g , todo ) click class level permissions and set read/write access for different user roles or public access acls you can pass an acl when creating or updating an object via rest calls this ensures only certain users or roles can read/write the data for more details, visit app security guidelines https //www back4app com/docs/security/parse security step 4 – writing cloud code functions why cloud code cloud code allows you to run server side functions, triggers, or validations—without managing your own servers you can add advanced business logic or integrate external apis from the server side example cloud function a simple example is a function that calculates text length in your main js file on the back4app dashboard parse cloud define('calculatetextlength', async (request) => { const { text } = request params; if (!text) { throw new error('no text provided'); } return { length text length }; }); deployment deploy cloud code by either back4app cli back4app dashboard under cloud code > functions paste your code in the main js editor and click deploy calling cloud functions from golang you can call a cloud function via rest from your http client func callcalculatetextlength(txt string) (int, error) { body, = json marshal(map\[string]string{"text" txt}) req, err = http newrequest("post", "https //parseapi back4app com/functions/calculatetextlength", bytes newbuffer(body)) if err != nil { return 0, err } // headers req header set("x parse application id", "your application id") req header set("x parse rest api key", "your rest api key") req header set("content type", "application/json") client = \&http client{} resp, err = client do(req) if err != nil { return 0, err } defer resp body close() if resp statuscode != http statusok { bodybytes, = ioutil readall(resp body) return 0, fmt errorf("api error %s", string(bodybytes)) } var result struct { result map\[string]int `json "result"` } if err = json newdecoder(resp body) decode(\&result); err != nil { return 0, err } return result result\["length"], nil } step 5 – configuring authentication enable user authentication back4app uses a user class for authentication when you create a new user via rest, the backend will store credentials securely and generate a session token curl x post \\ h "x parse application id your app id" \\ h "x parse rest api key your rest api key" \\ h "content type application/json" \\ d '{"username" "alice", "password" "secret123", "email" "alice\@example com"}' \\ https //parseapi back4app com/users use the returned session token for subsequent requests that require user privileges in go, you’d send the same type of http request from an http client as demonstrated earlier social login for social logins like google or facebook, you’ll need to configure oauth settings on back4app these flows often involve exchanging tokens consult the sign in with apple / social login docs https //www back4app com/docs/platform/sign in with apple for details step 6 – handling file storage setup and upload you can store files on back4app by sending them as base64 encoded data or multipart/form data curl x post \\ h "x parse application id your app id" \\ h "x parse rest api key your rest api key" \\ h "content type application/json" \\ d '{ "file" { "name" "myimage png", " type" "file", "base64" "ivborw0kggoaaaansuheugaa " } }' \\ https //parseapi back4app com/files/myimage png after uploading, you can attach the file to an object by storing the returned file url or file pointer in go, create an http request in the same manner—just ensure you encode the file content properly step 7 – email verification and password reset importance email verification ensures users control the email provided, while password reset helps them recover accounts both features boost security and trust enabling email verification go to your back4app dashboard under email settings , enable verification emails customize your email templates if needed when a user signs up, a verification email is automatically sent to them password reset use the requestpasswordreset rest endpoint https //docs parseplatform org/rest/guide/#r passwordreset to initiate a password reset curl x post \\ h "x parse application id your app id" \\ h "x parse rest api key your rest api key" \\ h "content type application/json" \\ d '{"email" "alice\@example com"}' \\ https //parseapi back4app com/requestpasswordreset step 8 – scheduling tasks with cloud jobs what cloud jobs do cloud jobs run on a schedule to automate tasks like cleaning stale data or sending weekly newsletters parse cloud job('cleanupoldtodos', async (request) => { const todo = parse object extend('todo'); const query = new parse query(todo); // remove records older than 30 days // }); deploy this job and schedule it in your back4app dashboard > app settings > server settings > background jobs step 9 – integrating webhooks why webhooks webhooks let you notify external services when certain events happen for example, you might send slack alerts when new todo items are created go to the webhooks section in your back4app dashboard configure your endpoint (like https //your external service com/webhook ) assign triggers (e g , aftersave on todo ) you can also trigger external apis from cloud code by writing an http client request if you prefer direct control of events step 10 – exploring the back4app admin panel overview the back4app admin app is a point and click interface you can share with non technical team members to manage data enable the admin app go to more > admin app in your back4app dashboard enable it and create an admin user use your chosen subdomain to log in to a straightforward ui for data manipulation this frees you from writing direct queries or custom code to perform basic operations conclusion in this guide, you discovered how to build a backend for golang using back4app you explored how to connect to the database via restful apis, apply security measures with acls and clps, run scheduled tasks with cloud jobs, integrate with external services using webhooks, and set up user authentication and file storage with go’s http package and back4app’s robust features, you can craft a powerful backend that saves time and scales effortlessly now that you’ve mastered the basics, you can extend your golang handler function logic, connect to new api endpoints, and build a rich application that meets your needs next steps refine your golang app add advanced features like role based access, or optimize your http server for production learn more about real time queries integrate live queries for collaborative apps explore advanced back4app documentation fine tune your acls, logs, and analytics incorporate third party apis use cloud code or direct webhooks to expand your backend functionality