(CkPython) 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.

Chilkat Python Downloads install with pip pip3 install chilkat or download... Python Module for Windows, MacOS, Linux, Alpine Linux, Solaris

import sys
import 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()
# 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()

# Connect using TLS.
bAutoReconnect = True
success = rest.Connect("www.googleapis.com",443,True,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()
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 CkJsonObject
pObjVersioning = jsonReqBody.ObjectOf("versioning")
success = pObjVersioning.AddBoolAt(-1,"enabled",True)

# Show the HTTP request body we'll be sending.
print(jsonReqBody.emit())

# 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 != True):
    print(rest.lastErrorText())
    sys.exit()

# Read the response header.
responseStatusCode = rest.ReadResponseHeader()
if (responseStatusCode < 0):
    # We were unable to receive the response header.
    print(rest.lastErrorText())
    sys.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())
    print("Response header: " + rest.responseHeader())

# Read the response body.  In this case we're expecting it to be JSON..
responseBodyStr = rest.readRespBodyString()
if (rest.get_LastMethodSuccess() != True):
    # 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())
    sys.exit()

# Show the JSON response.
print("Json Response: " + responseBodyStr)