(Perl) Lower-Level REST API Methods (Google Cloud Storage)

The FullRequest* methods, such as FullRequestBinary, FullRequestMultipart, FullRequestNoBody, FullRequestStream, FullRequestString, etc. are high-level REST API methods that both send the request and receive the response. It is often the case that an application needs make a REST call, but with a finer level of control. The Chilkat REST API provides this feature. An application can break a REST call into the following parts:

1. Send the HTTP request. (via the SendReq* methods)
2. Receive the HTTP response header. (ReadResponseHeader)
3. Receive the HTTP response body. (via the ReadRespBody* methods)

This example demonstrates a REST call using SendReqStringBody, ReadResonseHeader, and ReadRespBodyString.

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use chilkat();

# This example demonstrates a REST call using SendReqStringBody, ReadResonseHeader, and ReadRespBodyString.
# It will create a bucket in Google Cloud Storage.

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

$gAuth = chilkat::CkAuthGoogle->new();
# Obtain an access token as shown in one of the following examples:
# See Get Access Token using a Service Account JSON Key
# See Get Access Token using a P12 File

$rest = chilkat::CkRest->new();

# Connect using TLS.
$bAutoReconnect = 1;
$success = $rest->Connect("www.googleapis.com",443,1,$bAutoReconnect);

# Provide the authentication credentials (i.e. the access key)
$success = $rest->SetAuthGoogle($gAuth);

# Build the JSON request body for creating a bucket.
# The only required property is the "name", but we'll add more
# to make a better example..
$jsonReqBody = chilkat::CkJsonObject->new();
$success = $jsonReqBody->AddStringAt(-1,"name","chilkat-bucket-c");
$success = $jsonReqBody->AddStringAt(-1,"kind","storage#bucket");
$success = $jsonReqBody->AddStringAt(-1,"location","US");
$success = $jsonReqBody->AddObjectAt(-1,"versioning");

# pObjVersioning is a JsonObject
$pObjVersioning = $jsonReqBody->ObjectOf("versioning");
$success = $pObjVersioning->AddBoolAt(-1,"enabled",1);

# Show the HTTP request body we'll be sending.
print $jsonReqBody->emit() . "\r\n";

# Add the required query parameter.
# See https://cloud.google.com/storage/docs/json_api/v1/buckets/insert
$success = $rest->AddQueryParam("project","chilkattest-1050");

# Add the Content-Type HTTP request header.
$success = $rest->AddHeader("Content-Type","application/json; charset=UTF-8");

# Send the REST HTTP request.
$success = $rest->SendReqStringBody("POST","/storage/v1/b",$jsonReqBody->emit());
if ($success != 1) {
    print $rest->lastErrorText() . "\r\n";
    exit;
}

# Read the response header.
$responseStatusCode = $rest->ReadResponseHeader();
if ($responseStatusCode < 0) {
    # We were unable to receive the response header.
    print $rest->lastErrorText() . "\r\n";
    exit;
}

if ($responseStatusCode != 200) {
    # The response was not successful.  We'll still need to receive 
    # the response body, which may contain an error message from the server.
    # If the response has no body, then the method for reading the
    # response body can still be called.  It will simply return with an empty
    # response body.

    # We can examine the response header and status text:
    print "Response status text: " . $rest->responseStatusText() . "\r\n";
    print "Response header: " . $rest->responseHeader() . "\r\n";
}

# Read the response body.  In this case we're expecting it to be JSON..
$responseBodyStr = $rest->readRespBodyString();
if ($rest->get_LastMethodSuccess() != 1) {
    # We were unable to receive the response body.
    # Note: If the response did not include a body (such as for cases where
    # the Content-Length header is 0, or if the response status code implicitly
    # indicates no body, then ReadRespBodyString returns cktrue, and the
    # responseBodyString will be an empty string.
    print $rest->lastErrorText() . "\r\n";
    exit;
}

# Show the JSON response.
print "Json Response: " . $responseBodyStr . "\r\n";