Dart Requires Chilkat v11.0.0+

Create S3 Pre-Signed URL for Upload

See more Amazon S3 Examples

Demonstrates how to generate a pre-signed URL for S3 uploads. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final http = CkHttp();

  http.awsAccessKey = 'AWS_ACCESS_KEY';
  http.awsSecretKey = 'AWS_SECRET_KEY';

  // Make sure to set your AWS region correctly
  http.awsRegion = 'us-east-1';

  final bucketName = 'chilkat200';
  final objectName = 'starfish/starfish.jpg';
  final awsService = 's3';
  final httpVerb = 'PUT';

  // The signed URL will be valid for this number of seconds:
  final numSecondsValid = 86400;

  // Choose between a URL beginning with "http://" or "https://"...
  final bUseHttps = true;

  // Generate the pre-signed URL
  final String preSignedUrl;
  try {
    preSignedUrl = http.s3GenPresignedUrl(httpVerb, bUseHttps, bucketName, objectName, numSecondsValid, awsService);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Presigned URL for Upload: $preSignedUrl');

  // Here's an example of a pre-signed URL
  // 
  // http://chilkat200.s3.amazonaws.com/starfish/starfish.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIBJLOVZVXAU2AFUA%2F20200623%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20200623T234049Z&X-Amz-Expires=86400&X-Amz-SignedHeaders=host&X-Amz-Signature=xxxxxeaea071178d772856c0a4e4c0114a8d9992f0d0812955e490d0exxxxxxx
  // 

  // You can use the pre-signed URL to upload from Chilkat
  // For example, upload by streaming from a local file
  final resp = CkHttpResponse();
  try {
    http.httpFile('PUT', preSignedUrl, 'qa_data/jpg/starfish.jpg', 'image/jpg', resp);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('response status code = ${resp.statusCode}');
  print('response body size: ${resp.contentLength}');
  if (resp.contentLength > 0) {
    print('response body:');
    print(resp.bodyStr);
  }
}