Added an example for sending push notification to FCM endpoint using …

gov2/sns/publish_to_fcm_endpoint.go

@@ -0,0 +1,89 @@
+package main
+
+import (
+"context"
+"encoding/json"
+"fmt"
+
+"github.com/aws/aws-sdk-go-v2/aws"
+"github.com/aws/aws-sdk-go-v2/config"
+"github.com/aws/aws-sdk-go-v2/service/sns"
+)
+
+// This code example shows you how to send a push notification to a Firebase Cloud Messaging (FCM) endpoint
+// using AWS SNS SDK.
+
+func main() {
+ctx := context.Background()
+
+sdkConfig, err := config.LoadDefaultConfig(ctx)
+if err != nil {
+fmt.Println("Couldn't load default configuration. Have you set up your AWS account?")
+fmt.Println(err)
+return
+}
+
+snsClient := sns.NewFromConfig(sdkConfig)
+
+notificationData := map[string]interface{}{
+"notification": map[string]string{
+"title": "Notification Title",
+"body": "Sample Body",
+},
+"data": map[string]string{
+"sampleData1": "Sample Data",
+"sampleData2": "Sample Data",
+},
+}
+
+// We need to Marshal this data into JSON format, then put it as a
+// value to GCM key inside another map, and then marshal that
+// map to get the required format to be sent to SNS.
+
+notificationDataJSON, err := json.Marshal(notificationData)
+
+if err != nil {
+fmt.Println(err)
+return
+}
+
+message := map[string]interface{}{
+"default": "Default Value",
+"GCM": string(notificationDataJSON),
+}
+
+messageJSON, err := json.Marshal(message)
+
+if err != nil {
+fmt.Println(err)
+return
+}
+
+endpointArn := "user-endpoint-arn"
+
+_, err = snsClient.Publish(ctx, &sns.PublishInput{
+TargetArn: &endpointArn,
+MessageStructure: aws.String("json"),
+Message: aws.String(string(messageJSON)),
+})
+
+if err != nil {
+fmt.Println(err)
+return
+}
+
+// or if you want to pass the message data directly as a string to avoid the double
+// JSON marshalling, you can do that by passing it in the following format:
+//
+// Message: aws.String(
+// "{\"default\":\"Default Value\","+
+// "\"GCM\":\"{\\\"notification\\\":{" +
+//	"\\\"body\\\":\\\"Body\\\"," +
+//	"\\\"title\\\":\\\"Title\\\"" +
+//	"}," +
+//	"\\\"data\\\":{" +
+//	"\\\"sampleData1\\\":\\\"Sample Data\\\"," +
+//	"\\\"sampleData2\\\":\\\"Sample Data\\\"" +
+//	"}}\"}"
+// ),
+}