httpin/README.md

httpin - HTTP Input for Go

HTTP Request from/to Go Struct

Documentation

Core Features

httpin helps you easily decode data from an HTTP request, including:

• Query parameters, e.g. ?name=john&is_member=true
• Headers, e.g. Authorization: xxx
• Form data, e.g. username=john&password=******
• JSON/XML Body, e.g. POST {"name":"john"}
• Path variables, e.g. /users/{username}
• File uploads

You only need to define a struct to receive/bind data from an HTTP request, without writing any parsing stuff code by yourself.

Since v0.15.0, httpin also supports creating an HTTP request (http.Request) from a Go struct instance.

httpin is:

• well documented: at https://ggicci.github.io/httpin/
• open integrated: with net/http, go-chi/chi, gorilla/mux, gin-gonic/gin, etc.
• extensible (advanced feature): by adding your custom directives. Read httpin - custom directives for more details.

Add Httpin Directives by Tagging the Struct Fields with in

type ListUsersInput struct {
	Token    string  `in:"query=access_token;header=x-access-token"`
	Page     int     `in:"query=page;default=1"`
	PerPage  int     `in:"query=per_page;default=20"`
	IsMember bool    `in:"query=is_member"`
    Search   *string `in:"query=search;omitempty"`
}

How to decode an HTTP request to Go struct?

func ListUsers(rw http.ResponseWriter, r *http.Request) {
	input := r.Context().Value(httpin.Input).(*ListUsersInput)

	if input.IsMember {
		// Do sth.
	}
	// Do sth.
}

How to encode a Go struct to HTTP request?

func SDKListUsers() {
	payload := &ListUsersInput{
		Token:    os.Getenv("MY_APP_ACCESS_TOKEN"),
		Page:     2,
		IsMember: true,
	}

	// Easy to remember, http.NewRequest -> httpin.NewRequest
	req, err := httpin.NewRequest("GET", "/users", payload)
	// ...
}

Why this package?

Compared with using net/http package

func ListUsers(rw http.ResponseWriter, r *http.Request) {
	page, err := strconv.ParseInt(r.FormValue("page"), 10, 64)
	if err != nil {
		// Invalid parameter: page.
		return
	}
	perPage, err := strconv.ParseInt(r.FormValue("per_page"), 10, 64)
	if err != nil {
		// Invalid parameter: per_page.
		return
	}
	isMember, err := strconv.ParseBool(r.FormValue("is_member"))
	if err != nil {
		// Invalid parameter: is_member.
		return
	}

	// Do sth.
}

Benefits	Before (use net/http package)	After (use ggicci/httpin package)
⌛️ Developer Time	😫 Expensive (too much parsing stuff code)	🚀 Faster (define the struct for receiving input data and leave the parsing job to httpin)
♻️ Code Repetition Rate	😞 High	😍 Lower
📖 Code Readability	😟 Poor	🤩 Highly readable
🔨 Maintainability	😡 Poor	🥰 Highly maintainable

Alternatives and Similars

• gorilla/schema: converts structs to and from form values
• google/go-querystring: encoding structs into URL query parameters