(PowerBuilder) (using AWS Signature Version 2) Streaming Download to File

The main purpose of this example is to demonstrate how to use the older Signature Version 2 authentication w/ S3. It uses V2 authentication to download a file.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
oleobject loo_Rest
integer li_BTls
integer li_Port
integer li_BAutoReconnect
integer li_Success
oleobject loo_AuthAws
integer li_ResponseStatusCode
oleobject loo_BodyStream
string ls_ErrResponse

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

loo_Rest = create oleobject
// Use "Chilkat_9_5_0.Rest" for versions of Chilkat < 10.0.0
li_rc = loo_Rest.ConnectToNewObject("Chilkat.Rest")
if li_rc < 0 then
    destroy loo_Rest
    MessageBox("Error","Connecting to COM object failed")
    return
end if

// Connect to the Amazon AWS REST server.
li_BTls = 1
li_Port = 443
li_BAutoReconnect = 1
// The file is located in the bucket named "chilkat100", which becomes part of the domain:
li_Success = loo_Rest.Connect("chilkat100.s3.amazonaws.com",li_Port,li_BTls,li_BAutoReconnect)

// Provide AWS credentials for the REST call.
loo_AuthAws = create oleobject
// Use "Chilkat_9_5_0.AuthAws" for versions of Chilkat < 10.0.0
li_rc = loo_AuthAws.ConnectToNewObject("Chilkat.AuthAws")

loo_AuthAws.AccessKey = "AWS_ACCESS_KEY"
loo_AuthAws.SecretKey = "AWS_SECRET_KEY"
loo_AuthAws.ServiceName = "s3"

// For AWS Signature Version 2, the following two properties need to be set:
loo_AuthAws.SignatureVersion = 2
// See http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAuthentication.html#ConstructingTheCanonicalizedResourceElement
loo_AuthAws.CanonicalizedResourceV2 = "/chilkat100/starfish.jpg"

li_Success = loo_Rest.SetAuthAws(loo_AuthAws)

// Send the request to download the JPG.
li_Success = loo_Rest.SendReqNoBody("GET","/starfish.jpg")
if li_Success <> 1 then
    Write-Debug loo_Rest.LastErrorText
    destroy loo_Rest
    destroy loo_AuthAws
    return
end if

// Read the response header.
li_ResponseStatusCode = loo_Rest.ReadResponseHeader()
if li_ResponseStatusCode < 0 then
    Write-Debug loo_Rest.LastErrorText
    destroy loo_Rest
    destroy loo_AuthAws
    return
end if

Write-Debug "Response status code = " + string(li_ResponseStatusCode)

// We expect a 200 response status if the JPG data is coming.
// Otherwise, we'll get a string response body with an error message(or no response body).
if li_ResponseStatusCode = 200 then

    loo_BodyStream = create oleobject
    // Use "Chilkat_9_5_0.Stream" for versions of Chilkat < 10.0.0
    li_rc = loo_BodyStream.ConnectToNewObject("Chilkat.Stream")

    // The stream's sink will be a file.
    loo_BodyStream.SinkFile = "qa_output/starfish.jpg"

    // Read the response body to the stream.  Given that we've
    // set the stream's sink to a file, it will stream directly
    // to the file.
    li_Success = loo_Rest.ReadRespBodyStream(loo_BodyStream,1)
    if li_Success <> 1 then
        Write-Debug loo_Rest.LastErrorText
        destroy loo_Rest
        destroy loo_AuthAws
        destroy loo_BodyStream
        return
    end if

    Write-Debug "Successfully received the JPG file."

else
    ls_ErrResponse = loo_Rest.ReadRespBodyString()
    if loo_Rest.LastMethodSuccess <> 1 then
        Write-Debug loo_Rest.LastErrorText
    else
        Write-Debug ls_ErrResponse
    end if

end if



destroy loo_Rest
destroy loo_AuthAws
destroy loo_BodyStream