Ruby

(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. Ruby

require 'chilkat'

success = false

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

rest = Chilkat::CkRest.new()

# Connect to the Amazon AWS REST server.
bTls = true
port = 443
bAutoReconnect = true
# The file is located in the bucket named "chilkat100", which becomes part of the domain:
success = rest.Connect("chilkat100.s3.amazonaws.com",port,bTls,bAutoReconnect)

# Provide AWS credentials for the REST call.
authAws = Chilkat::CkAuthAws.new()
authAws.put_AccessKey("AWS_ACCESS_KEY")
authAws.put_SecretKey("AWS_SECRET_KEY")
authAws.put_ServiceName("s3")

# For AWS Signature Version 2, the following two properties need to be set:
authAws.put_SignatureVersion(2)
# See http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAuthentication.html#ConstructingTheCanonicalizedResourceElement
authAws.put_CanonicalizedResourceV2("/chilkat100/starfish.jpg")

success = rest.SetAuthAws(authAws)

# Send the request to download the JPG.
success = rest.SendReqNoBody("GET","/starfish.jpg")
if (success != true)
    print rest.lastErrorText() + "\n";
    exit
end

# Read the response header.
responseStatusCode = rest.ReadResponseHeader()
if (responseStatusCode < 0)
    print rest.lastErrorText() + "\n";
    exit
end

print "Response status code = " + responseStatusCode.to_s() + "\n";

# 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 (responseStatusCode == 200)

    bodyStream = Chilkat::CkStream.new()

    # The stream's sink will be a file.
    bodyStream.put_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.
    success = rest.ReadRespBodyStream(bodyStream,true)
    if (success != true)
        print rest.lastErrorText() + "\n";
        exit
    end

    print "Successfully received the JPG file." + "\n";

else
    errResponse = rest.readRespBodyString()
    if (rest.get_LastMethodSuccess() != true)
        print rest.lastErrorText() + "\n";
    else
        print errResponse + "\n";
    end

end