Building an HTTP Function with Go

HTTP functions do not support direct code deployment using Go. This section uses binary conversion as an example to describe how to deploy Go programs on FuntionGraph.

Create the source file main.go. The code is as follows:

// main.go
package main

import (
	"fmt"
	"net/http"

	"github.com/emicklei/go-restful"
)

func registerServer() {
	fmt.Println("Running a Go Http server at localhost:8000/")

	ws := new(restful.WebService)
	ws.Path("/")

	ws.Route(ws.GET("/hello").To(Hello))
	c := restful.DefaultContainer
	c.Add(ws)
	fmt.Println(http.ListenAndServe(":8000", c))
}

func Hello(req *restful.Request, resp *restful.Response) {
	resp.Write([]byte("nice to meet you"))
}

func main() {
	registerServer()
}

# bootstrap
/opt/function/code/go-http-demo

In main.go, an HTTP server is started using port 8000, and an API whose path is /hello is registered. When the API is invoked, "nice to meet you" is returned.

Compiling and packaging

1. On the Linux server, compile the preceding code using the go build -o go-http-demo main.go command. Then, compress go-http-demo and bootstrap into a ZIP package named xxx.zip.
2. To use the Golang compiler to complete packaging on a Windows host, perform the following steps:

   # Switch the compilation environment
   # Check the previous Golang compilation environment
   go env
   # Set the following parameters to the corresponding value of Linux
   set GOARCH=amd64
   go env -w GOARCH=amd64
   set GOOS=linux
   go env -w GOOS=linux
   
   # go build -o [target executable program] [source program]
   # Example
   go build -o go-http-demo main.go
   
   # Restore the compilation environment
   set GOARCH=amd64
   go env -w GOARCH=amd64
   set GOOS=windows
   go env -w GOOS=windows

Creating an HTTP function and uploading code

Create an HTTP function and upload the xxx.zip package. For details, see Creating an HTTP Function.

Creating an APIG trigger

Create an APIG trigger by referring to Using an APIG Trigger. Set the authentication mode to None for debugging.

Figure 1 APIG trigger

Invocation test

Copy the URL of the APIG trigger and the /hello path registered in the code to the address box of the browser. The following information is displayed.

Figure 2 Request result