(Go) 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.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

    success := false

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

    http := Http_Ref.html">chilkat.NewHttp()

    http.SetAwsAccessKey("AWS_ACCESS_KEY")
    http.SetAwsSecretKey("AWS_SECRET_KEY")

    // Make sure to set your AWS region correctly
    http.SetAwsRegion("us-east-1")

    bucketName := "chilkat100"
    objectName := "starfish/starfish.jpg"
    localFilePath := "qa_output/starfish.jpg"
    awsService := "s3"

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

    // Choose between a URL beginning with "http://" or "https://"...
    bUseHttps := false

    // Generate the pre-signed URL
    preSignedUrl := http.S3_GenPresignedUrl("GET",bUseHttps,bucketName,objectName,numSecondsValid,awsService)
    if http.LastMethodSuccess() == false {
        fmt.Println(http.LastErrorText())
        http.DisposeHttp()
        return
    }

    // The following URL can be copy-and-pasted into a browser..
    fmt.Println("Pre-Signed AWS S3 URL: ", *preSignedUrl)

    // 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.
    success = http.Download(*preSignedUrl,"c:/temp/qa_output/starfish.jpg")
    if success == false {
        fmt.Println(http.LastErrorText())
        http.DisposeHttp()
        return
    }

    fmt.Println("Success.")

    http.DisposeHttp()