Lianja
Generate an AWS (S3) Pre-Signed URL to Download File

Demonstrates how to generate a pre-signed URL to download a file from the Amazon S3 service.
Chilkat Lianja Downloads

Lianja
llSuccess = .F.

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

loHttp = createobject("CkHttp")

loHttp.AwsAccessKey = "AWS_ACCESS_KEY"
loHttp.AwsSecretKey = "AWS_SECRET_KEY"

// Make sure to set your AWS region correctly
loHttp.AwsRegion = "us-east-1"

lcBucketName = "chilkat100"
lcObjectName = "starfish/starfish.jpg"
lcLocalFilePath = "qa_output/starfish.jpg"
lcAwsService = "s3"

// The signed URL will be valid for this number of seconds:
lnNumSecondsValid = 86400

// Choose between a URL beginning with "http://" or "https://"...
llBUseHttps = .F.

// Generate the pre-signed URL
lcPreSignedUrl = loHttp.S3_GenPresignedUrl("GET",llBUseHttps,lcBucketName,lcObjectName,lnNumSecondsValid,lcAwsService)
if (loHttp.LastMethodSuccess = .F.) then
    ? loHttp.LastErrorText
    release loHttp
    return
endif

// The following URL can be copy-and-pasted into a browser..
? "Pre-Signed AWS S3 URL: " + lcPreSignedUrl

// Here's an example of a pre-signed URL. 
// This URL will only work within 1 day (86400 seconds) after the time this example was published.
// 
//     http://chilkat100.s3.amazonaws.com/starfish/starfish.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=16QXXDGY83AJJR6RVQ02%2F20170111%2Fus-west-2%2Fs3%2Faws4_request&X-Amz-Date=20170111T161959Z&X-Amz-Expires=86400&X-Amz-SignedHeaders=host&X-Amz-Signature=72bf4fd9a15d7bbcdd313a3318d937a778905f62a3fbff9b789d8dc28acd9232

// Now try to do an HTTP Download using the signed URL.
llSuccess = loHttp.Download(lcPreSignedUrl,"c:/temp/qa_output/starfish.jpg")
if (llSuccess = .F.) then
    ? loHttp.LastErrorText
    release loHttp
    return
endif

? "Success."


release loHttp