APIG Event Source

API Gateway (APIG) is an API hosting service that helps enterprises to build, manage, and deploy APIs at any scale. With APIG, your function can be invoked through HTTPS by using a custom REST API and a specified backend. You can map each API operation (such as, GET and PUT) to a specific function. APIG invokes the relevant function when an HTTPS request is sent to the API backend.

For more information about how to use HTTPS calls to trigger functions, see :Using an APIG (Dedicated) trigger.

Example APIG Event

apig_base64_event.json

{
  "body": "eyJuYW1lIjogIk9wZW5UZWxla29tQ2xvdWQifQ==",
  "requestContext": {
      "apiId": "bc1dcffd-aa35-474d-897c-d53425a4c08e",
      "requestId": "11cdcdcf33949dc6d722640a13091c77",
      "stage": "RELEASE"
  },
  "queryStringParameters": {
      "responseType": "html"
  },
  "httpMethod": "GET",
  "pathParameters": {},
  "headers": {
      "accept-language": "q=0.5,en-US;q=0.3,en;q=0.2",
      "accept-encoding": "gzip, deflate, br",
      "x-forwarded-port": "443",
      "x-forwarded-for": "103.218.216.98",
      "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
      "upgrade-insecure-requests": "1",
      "host": "host",
      "x-forwarded-proto": "https",
      "pragma": "no-cache",
      "cache-control": "no-cache",
      "x-real-ip": "103.218.216.98",
      "user-agent": "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0"
  },
  "path": "/",
  "isBase64Encoded": true
}

Parameter description

Parameter	Type	Description
body	String	Actual request body in string format (Base64 encoded).
requestContext	Map	Request information, including the API gateway configuration, request ID, authentication information, and source.
httpMethod	String	HTTP method
queryStringParameters	Map	Query strings configured in APIG and their actual values
pathParameters	Map	Path parameters configured in APIG and their actual values
headers	Map	Complete headers
path	String	Complete path
isBase64Encoded	Boolean	Default value: true (see Notes below)

Notes

• When calling a function using APIG, isBase64Encoded is valued true by default, indicating that the request body transferred to FunctionGraph is encoded using Base64 and must be decoded for processing.

• The function must return characters strings by using the following structure.

  {
    "isBase64Encoded": "true|false",
    "statusCode": "httpStatusCode",
    "headers": {"headerName":"headerValue"},
    "body": "..."
  }
  

Example

handler.go

package main

import (
	"encoding/base64"
	"encoding/json"
	"fmt"

	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/events/apig"
	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/go-api/context"
	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/pkg/runtime"
)

// Example for API Gateway (Dedicated Gateway) handler
func ApigTest(payload []byte, ctx context.RuntimeContext) (interface{}, error) {

	var apigEvent apig.APIGTriggerEvent
	err := json.Unmarshal(payload, &apigEvent)
	if err != nil {
		fmt.Println("Unmarshal failed")
		return "invalid data", err
	}
	ctx.GetLogger().Logf("payload:%s", apigEvent.String())

	// body processing example

	var body string

	if apigEvent.IsBase64Encoded {
		body = apigEvent.GetRawBody()
		ctx.GetLogger().Logf("Decoded body: %s", body)
	} else {
		body = apigEvent.Body
		ctx.GetLogger().Logf("Body: %s", body)
	}

	// path parameters example
	pathParameters := apigEvent.PathParameters
	if pathParameters != nil {

		for key, value := range pathParameters {
			ctx.GetLogger().Logf("Path parameter - %s: %s", key, value)
		}
	}

	// headers example
	headers := apigEvent.Headers
	if headers != nil {
		for key, value := range headers {
			ctx.GetLogger().Logf("Header - %s: %s", key, value)
		}
	}

	var returnBody string

	if apigEvent.IsBase64Encoded {
		returnBodyBytes, err := base64.StdEncoding.DecodeString(body)
		if err != nil {
			return nil, err
		}
		returnBody = string(returnBodyBytes)
	} else {
		returnBody = body
	}

	apigResp := apig.APIGTriggerResponse{
		Body: returnBody,
		Headers: map[string]string{
			"content-type": "application/json",
		},
		StatusCode: 200,
	}

	return apigResp, nil
}

func main() {
	runtime.Register(ApigTest)
}

last updated: 2026-02-02 13:44:43 UTC - commit: 866bacca0eba208407ae5eac0c4585032715ff2c