Invoke a Function using OCI signature using OCI Go SDK

call-functions-using-oci-go-sdk.go

package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"net/http"
	"time"

	"github.com/oracle/oci-go-sdk/common"
)

func main() {

	functionEndpoint := flag.String("http_trigger_endpoint", "", "Function HTTP Trigger endpoint")
	flag.Parse()

	if *functionEndpoint == "" {
		fmt.Println("please specify function http trigger endpoint using --http_trigger_endpoint")
		return
	}

	fmt.Println("Invoking function endpoint", *functionEndpoint)

	client := http.Client{Timeout: 1 * time.Minute}
	request, err := http.NewRequest("GET", *functionEndpoint, nil)
	if err != nil {
		fmt.Println("failed to create HTTP request", err)
		return
	}

	request.Header.Set("Date", time.Now().UTC().Format(http.TimeFormat))
	provider := common.DefaultConfigProvider()
	signer := common.DefaultRequestSigner(provider)

	err = signer.Sign(request)

	if err != nil {
		fmt.Println("Error signing request", err)
	}
	fmt.Println("Request signing done. Invoking function...")

	var resp *http.Response
	resp, err = client.Do(request)

	if err != nil {
		fmt.Println("error invoking function", err)
		return
	}

	defer resp.Body.Close()

	fmt.Println("function response status -", resp.Status)
	var bytesResp []byte
	if resp.StatusCode == http.StatusOK {
		bytesResp, err = ioutil.ReadAll(resp.Body)
		if err != nil {
			fmt.Println("could not read response from response body", err)
			return
		}

		functionResponse := string(bytesResp)
		fmt.Println("function response -", functionResponse)
	}
}