HTTP Clients

Request Headers

Headers carry metadata such as accepted formats or authorization tokens.

request header Client code prepares headers as request metadata before a request is sent.

Request Headers

token
request_headers.go
Replay: real traced execution (multi-file project)
package main

import "fmt"

func main() {
	var token = "demo-token"
	headers := map[string]string{}

	headers["Accept"] = "application/json"
	headers["Authorization"] = "Bearer " + token

	fmt.Println("accept=", headers["Accept"])
	fmt.Println("authPrefix=", headers["Authorization"][:6])
	fmt.Println("token=", token)
}

package main

import "fmt"

func main() {
	var token = "read-token"
	headers := map[string]string{}

	headers["Accept"] = "application/json"
	headers["Authorization"] = "Bearer " + token

	fmt.Println("accept=", headers["Accept"])
	fmt.Println("authPrefix=", headers["Authorization"][:6])
	fmt.Println("token=", token)
}

package main

import "fmt"

func main() {
	var token = "admin-token"
	headers := map[string]string{}

	headers["Accept"] = "application/json"
	headers["Authorization"] = "Bearer " + token

	fmt.Println("accept=", headers["Accept"])
	fmt.Println("authPrefix=", headers["Authorization"][:6])
	fmt.Println("token=", token)
}

  1. token ← "demo-token", headers ← map[string]string{}, headers["Accept"] ← "application/json"

    5func main() {6  var token→ "demo-token" = "demo-token" //@token="read-token", "admin-token"7  headers→ map[string]string{} := map[string]string{}89  headers["Accept"]→ "application/json" = "application/json"10  headers["Authorization"]→ "Bearer demo-token" = "Bearer " + token"demo-token"1112  fmt.Println("accept=", headers["Accept"]"application/json")13  fmt.Println("authPrefix=", headers["Authorization"]"Bearer demo-token"[:6])14  fmt.Println("token=", token"demo-token")15}
    outputaccept= application/json
authPrefix= Bearer
token= demo-token

  1. token ← "read-token", headers ← map[string]string{}, headers["Accept"] ← "application/json"

    5func main() {6  var token→ "read-token" = "read-token"7  headers→ map[string]string{} := map[string]string{}89  headers["Accept"]→ "application/json" = "application/json"10  headers["Authorization"]→ "Bearer read-token" = "Bearer " + token"read-token"1112  fmt.Println("accept=", headers["Accept"]"application/json")13  fmt.Println("authPrefix=", headers["Authorization"]"Bearer read-token"[:6])14  fmt.Println("token=", token"read-token")15}
    outputaccept= application/json
authPrefix= Bearer
token= read-token

  1. token ← "admin-token", headers ← map[string]string{}, headers["Accept"] ← "application/json"

    5func main() {6  var token→ "admin-token" = "admin-token"7  headers→ map[string]string{} := map[string]string{}89  headers["Accept"]→ "application/json" = "application/json"10  headers["Authorization"]→ "Bearer admin-token" = "Bearer " + token"admin-token"1112  fmt.Println("accept=", headers["Accept"]"application/json")13  fmt.Println("authPrefix=", headers["Authorization"]"Bearer admin-token"[:6])14  fmt.Println("token=", token"admin-token")15}
    outputaccept= application/json
authPrefix= Bearer
token= admin-token