Visual FoxPro

(using AWS Signature Version 2) Streaming Download to File

See more Amazon S3 (new) Examples

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. Visual FoxPro

LOCAL lnSuccess
LOCAL loRest
LOCAL lnBTls
LOCAL lnPort
LOCAL lnBAutoReconnect
LOCAL loAuthAws
LOCAL lnResponseStatusCode
LOCAL loBodyStream
LOCAL lcErrResponse

lnSuccess = 0

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

loRest = CreateObject('Chilkat.Rest')

* Connect to the Amazon AWS REST server.
lnBTls = 1
lnPort = 443
lnBAutoReconnect = 1
* The file is located in the bucket named "chilkat100", which becomes part of the domain:
lnSuccess = loRest.Connect("chilkat100.s3.amazonaws.com",lnPort,lnBTls,lnBAutoReconnect)

* Provide AWS credentials for the REST call.
loAuthAws = CreateObject('Chilkat.AuthAws')
loAuthAws.AccessKey = "AWS_ACCESS_KEY"
loAuthAws.SecretKey = "AWS_SECRET_KEY"
loAuthAws.ServiceName = "s3"

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

lnSuccess = loRest.SetAuthAws(loAuthAws)

* Send the request to download the JPG.
lnSuccess = loRest.SendReqNoBody("GET","/starfish.jpg")
IF (lnSuccess <> 1) THEN
    ? loRest.LastErrorText
    RELEASE loRest
    RELEASE loAuthAws
    CANCEL
ENDIF

* Read the response header.
lnResponseStatusCode = loRest.ReadResponseHeader()
IF (lnResponseStatusCode < 0) THEN
    ? loRest.LastErrorText
    RELEASE loRest
    RELEASE loAuthAws
    CANCEL
ENDIF

? "Response status code = " + STR(lnResponseStatusCode)

* 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 (lnResponseStatusCode = 200) THEN

    loBodyStream = CreateObject('Chilkat.Stream')

    * The stream's sink will be a file.
    loBodyStream.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.
    lnSuccess = loRest.ReadRespBodyStream(loBodyStream,1)
    IF (lnSuccess <> 1) THEN
        ? loRest.LastErrorText
        RELEASE loRest
        RELEASE loAuthAws
        RELEASE loBodyStream
        CANCEL
    ENDIF

    ? "Successfully received the JPG file."

ELSE
    lcErrResponse = loRest.ReadRespBodyString()
    IF (loRest.LastMethodSuccess <> 1) THEN
        ? loRest.LastErrorText
    ELSE
        ? lcErrResponse
    ENDIF

ENDIF

RELEASE loRest
RELEASE loAuthAws
RELEASE loBodyStream