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- Committer: William Grant
- Date: 2012-04-20 02:20:58 UTC
- mfrom: (6.1.70 trunk)
- Revision ID: william.grant@canonical.com-20120420022058-3nkracsmlg7akydu
Merge trunk.
- files added:
- grackle/error.py
- files modified:
- Makefile
added
removed
grackle/service.py
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__metaclass__ = type
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__all__ = [
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'ForkedFakeService',
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'GrackleService',
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]
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import httplib
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import logging
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import os
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from signal import SIGKILL
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import simplejson
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import sys
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from wsgiref.headers import Headers
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from wsgiref.simple_server import make_server
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from wsgiref.util import shift_path_info
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from grackle.store import (
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MemoryStore,
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)
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class GrackleService:
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"""A request handler that forwards to an archive store."""
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def __init__(self, store):
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self.store = store
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self.logger = logging.getLogger('http')
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def __call__(self, environ, start_response):
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self.environ = environ
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self.start_response = start_response
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self.headers = Headers([('content-type', 'application/json')])
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self.method = environ['REQUEST_METHOD']
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if '://' in environ['PATH_INFO']:
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# All the needed information is embedded in PATH_INFO.
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shift_path_info(environ) # shift the host and or port.
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self.application = shift_path_info(environ)
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path = environ['PATH_INFO'].split('/')
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path.pop(0) # Pop the scheme.
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self.path = path
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elif environ['SCRIPT_NAME'] == '':
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# Remove the application to set the path.
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self.application = shift_path_info(environ)
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self.path = environ['PATH_INFO'].split('/')
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else:
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self.application = environ['SCRIPT_NAME']
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self.path = environ['PATH_INFO'].split('/')
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self.query_string = environ['QUERY_STRING']
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return self.handle_request()
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def handle_request(self):
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"""Select the method to handle the request and return a response."""
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if self.application != 'archive':
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return self.send_response(httplib.NOT_FOUND)
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elif self.method == 'PUT':
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return self.do_PUT()
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elif self.method == 'POST':
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return self.do_POST()
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elif self.method == 'GET':
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return self.do_GET()
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return self.send_response(httplib.METHOD_NOT_ALLOWED)
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def send_response(self, code, response='', reason=None):
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"""Set the status code and reason, then return the response."""
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if reason is None:
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reason = httplib.responses[code]
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response_status = '%s %s' % (code, reason)
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self.start_response(response_status, self.headers.items())
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return [response]
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def do_PUT(self):
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"""Create an archive or message on PUT."""
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if len(self.path) == 1:
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# This expected path is /archive/archive_id.
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try:
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self.store.put_archive(self.path[0])
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return self.send_response(httplib.CREATED)
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except Exception, error:
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return self.send_response(
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httplib.BAD_REQUEST, reason=error.__doc__)
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elif len(self.path) == 2:
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# This expected path is /archive/archive_id/message_id.
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try:
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put_input = self.environ['wsgi.input']
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message = put_input.read(int(self.environ['CONTENT_LENGTH']))
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self.store.put_message(self.path[0], self.path[1], message)
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return self.send_response(httplib.CREATED)
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except Exception, error:
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return self.send_response(
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httplib.BAD_REQUEST, reason=error.__doc__)
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def do_POST(self):
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"""Change a message on POST."""
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if len(self.path) == 2:
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# This expected path is /archive/archive_id/message_id.
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try:
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# This expected path is /archive/archive_id/message_id.
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response = self.store.hide_message(
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self.path[0], self.path[1], self.query_string)
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response = simplejson.dumps(response)
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return self.send_response(httplib.OK, response=response)
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except Exception, error:
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return self.send_response(
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httplib.BAD_REQUEST, reason=error.__doc__)
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def do_GET(self):
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"""Retrieve a list of messages on GET."""
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try:
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response = self.store.get_messages(
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self.path[0], self.query_string)
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response = simplejson.dumps(response)
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return self.send_response(httplib.OK, response=response)
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except Exception, error:
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return self.send_response(
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httplib.BAD_REQUEST, reason=error.__doc__)
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def log_message(self, format, *args):
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"""Override log_message to use standard Python logging."""
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message = "%s - - [%s] %s\n" % (
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self.address_string(), self.log_date_time_string(), format % args)
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self.logger.info(message)
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class ForkedFakeService:
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"""A Grackle service fake, as a ContextManager."""
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def __init__(self, port, message_archives=None, write_logs=False):
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"""Constructor.
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:param port: The tcp port to use.
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:param message_archives: A dict of lists of dicts representing
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archives of messages. The outer dict represents the archive,
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the list represents the list of messages for that archive.
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:param write_logs: If true, log messages will be written to stdout.
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"""
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self.pid = None
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self.port = port
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if message_archives is None:
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self.message_archives = {}
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else:
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self.message_archives = message_archives
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self.read_end, self.write_end = os.pipe()
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self.write_logs = write_logs
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@staticmethod
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def from_client(client, message_archives=None):
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"""Instantiate a ForkedFakeService from the client.
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:param port: The client to provide service for.
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:param message_archives: A dict of lists of dicts representing
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archives of messages. The outer dict represents the archive,
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the list represents the list of messages for that archive.
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"""
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return ForkedFakeService(client.port, message_archives)
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def is_ready(self):
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"""Tell the parent process that the server is ready for writes."""
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os.write(self.write_end, 'asdf')
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def __enter__(self):
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"""Run the service.
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Fork and start a server in the child. Return when the server is ready
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for use."""
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pid = os.fork()
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if pid == 0:
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self.start_server()
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self.pid = pid
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os.read(self.read_end, 1)
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return
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def start_server(self):
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"""Start the HTTP server."""
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app = GrackleService(MemoryStore(self.message_archives))
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service = make_server('', self.port, app)
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self.is_ready()
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if self.write_logs:
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logging.basicConfig(
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stream=sys.stderr, level=logging.INFO)
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service.serve_forever()
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def __exit__(self, exc_type, exc_val, traceback):
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os.kill(self.pid, SIGKILL)
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if __name__ == '__main__':
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app = GrackleService(MemoryStore({}))
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service = make_server('', 8787, app)
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service.serve_forever()
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