Gap

Gap is a web framework aimed at removing HTTP boilerplate from your application.

Docs

• User guide: https://hugollm.github.io/gap
• API reference: https://pkg.go.dev/github.com/hugollm/gap

Overview

Here's a minimal example of an application with one endpoint:

package main

import (
    "github.com/hugollm/gap"
)

func main() {
    app := gap.New()
    app.Route("GET", "/", helloEndpoint)
    app.Run()
}

type helloInput struct {
    UserAgent string `request:"header,user-agent"`
}

type helloOutput struct {
    Message string `response:"json,message"`
}

func helloEndpoint(input helloInput) (helloOutput, error) {
    return helloOutput{"hello " + input.UserAgent}, nil
}

This endpoint gets the User-Agent header from the request and outputs a hello message on the response body as JSON.

GET /
User-Agent: golang
---
200 {"message": "hello golang"}

Note how the endpoint function does not depend on the framework. Tag annotations take care of binding inputs and outputs to requests and responses. This makes it much easier to write and test your app.