Added Golang samples for Lambda connection with RDS using IAM and Lambda integration with DocDB

integration-docdb-to-lambda/main.go

@@ -0,0 +1,48 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/aws/aws-lambda-go/lambda"
+)
+
+type Event struct {
+	Events []Record `json:"events"`
+}
+
+type Record struct {
+	Event struct {
+		OperationType string `json:"operationType"`
+		NS            struct {
+			DB   string `json:"db"`
+			Coll string `json:"coll"`
+		} `json:"ns"`
+		FullDocument interface{} `json:"fullDocument"`
+	} `json:"event"`
+}
+
+func main() {
+	lambda.Start(handler)
+}
+
+func handler(ctx context.Context, event Event) (string, error) {
+	fmt.Println("Loading function")
+	for _, record := range event.Events {
+		logDocumentDBEvent(record)
+	}
+
+	return "OK", nil
+}
+
+func logDocumentDBEvent(record Record) {
+	fmt.Printf("Operation type: %s\n", record.Event.OperationType)
+	fmt.Printf("db: %s\n", record.Event.NS.DB)
+	fmt.Printf("collection: %s\n", record.Event.NS.Coll)
+	docBytes, _ := json.MarshalIndent(record.Event.FullDocument, "", "  ")
+	fmt.Printf("Full document: %s\n", string(docBytes))
+}

lambda-function-connect-rds-iam/main.go

@@ -0,0 +1,79 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+/*
+Golang v2 code here.
+*/
+
+package main
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+
+	"github.com/aws/aws-lambda-go/lambda"
+	"github.com/aws/aws-sdk-go-v2/config"
+	"github.com/aws/aws-sdk-go-v2/feature/rds/auth"
+	_ "github.com/go-sql-driver/mysql"
+)
+
+type MyEvent struct {
+	Name string `json:"name"`
+}
+
+func HandleRequest(event *MyEvent) (map[string]interface{}, error) {
+
+	var dbName string = "DatabaseName"
+	var dbUser string = "DatabaseUser"
+	var dbHost string = "mysqldb.123456789012.us-east-1.rds.amazonaws.com"
+	var dbPort int = 3306
+	var dbEndpoint string = fmt.Sprintf("%s:%d", dbHost, dbPort)
+	var region string = "us-east-1"
+
+	cfg, err := config.LoadDefaultConfig(context.TODO())
+	if err != nil {
+		panic("configuration error: " + err.Error())
+	}
+
+	authenticationToken, err := auth.BuildAuthToken(
+		context.TODO(), dbEndpoint, region, dbUser, cfg.Credentials)
+	if err != nil {
+		panic("failed to create authentication token: " + err.Error())
+	}
+
+	dsn := fmt.Sprintf("%s:%s@tcp(%s)/%s?tls=true&allowCleartextPasswords=true",
+		dbUser, authenticationToken, dbEndpoint, dbName,
+	)
+
+	db, err := sql.Open("mysql", dsn)
+	if err != nil {
+		panic(err)
+	}
+
+	defer db.Close()
+
+	var sum int
+	err = db.QueryRow("SELECT ?+? AS sum", 3, 2).Scan(&sum)
+	if err != nil {
+		panic(err)
+	}
+	s := fmt.Sprint(sum)
+	message := fmt.Sprintf("The selected sum is: %s", s)
+
+	messageBytes, err := json.Marshal(message)
+	if err != nil {
+		return nil, err
+	}
+
+	messageString := string(messageBytes)
+	return map[string]interface{}{
+		"statusCode": 200,
+		"headers":    map[string]string{"Content-Type": "application/json"},
+		"body":       messageString,
+	}, nil
+}
+
+func main() {
+	lambda.Start(HandleRequest)
+}