fonar / paypalhttp_python

PayPal HttpClient

PayPalHttp is a generic HTTP Client.

In it's simplest form, an HttpClient exposes an #execute method which takes an HTTP request, executes it against the domain described in an Environment, and returns an HttpResponse. It throws an Error, and potentially an HttpError, if anything goes wrong during execution.

Environment

An Environment describes a domain that hosts a REST API, against which an HttpClient will make requests. Environment is a simple class that contains one property, base_url.

env = Environment("https://example.com")

Requests

HTTP request objects contain all the information needed to make an HTTP request against the REST API. Specifically, one request object describes a path, a verb, any path/query/form parameters, headers, attached files for upload, and body data.

Responses

HttpResponses contain information returned by a server in response to a request as described above. They contain a status_code, headers, and a result, which represents any data returned by the server.

class GenericRequest():
  def __init__(self):
    self.path = "/path/to/resource"
    self.verb = "GET"
    self.headers = {
      "X-Custom-Header": "custom value"
    }

resp = client.execute(GenericRequest())

Injectors

Injectors are functions that can be used for executing arbitrary pre-flight logic, such as modifying a request or logging data. Injectors are attached to an HttpClient using the #add_injector method. They may take the form of a class that implements __call__, a function reference, or a lambda expression.

The HttpClient executes its Injectors in a first-in, first-out order, before each request.

client = HttpClient(env)

class HeadersInjector():
  def __call__(req):
    req.headers["Request-Id"] = "abcd"

client.add_injector(HeadersInjector())

def inject_query_param(req):
  req.path += "?query=param"

client.add_injector(inject_query_param)

client.add_injector(lambda req: print req)

...

Error Handling

HttpClient#execute may raise an IOError if something went wrong during the course of execution. If the server returned a non-200 response, this execption will be an instance of HttpError that will contain a status code and headers you can use for debugging.

try:
  resp = client.execute(req)
  status_code = resp.status_code
  headers = resp.headers
  response_data = resp.result
except HttpError as err:
  # Inspect this exception for details
  status_code = err.status_code
  headers = err.headers
  message = str(err)
except IOError as ioe:
  # Something else went wrong
  print ioe

Serializer

(De)Serialization of request and response data is done by instances of Encoder. PayPalHttp currently supports json encoding out of the box.

License

PayPalHttp-Python is open source and available under the MIT license. See the LICENSE file for more info.

Contributing

Pull requests and issues are welcome. Please see CONTRIBUTING.md for more details.