Add some documentation for cluster management
[kamaki] / kamaki / clients / __init__.py
index 3cacc3f..266b3fc 100644 (file)
@@ -1,4 +1,4 @@
-# Copyright 2011-2012 GRNET S.A. All rights reserved.
+# Copyright 2011-2013 GRNET S.A. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or
 # without modification, are permitted provided that the following
 # interpreted as representing official policies, either expressed
 # or implied, of GRNET S.A.
 
-from urllib2 import quote
+from urllib2 import quote, unquote
+from urlparse import urlparse
 from threading import Thread
 from json import dumps, loads
 from time import time
+from httplib import ResponseNotReady, HTTPException
+from time import sleep
+from random import random
+from logging import getLogger
 
-from kamaki.clients.utils import get_logger, add_file_logger, get_log_filename
-from kamaki.clients.connection.kamakicon import KamakiHTTPConnection
-from kamaki.clients.connection.errors import KamakiConnectionError
-from kamaki.clients.connection.errors import KamakiResponseError
+from objpool.http import PooledHTTPConnection
 
-DEBUG_LOG = get_log_filename()
-add_file_logger('clients.send', __name__, filename=DEBUG_LOG)
-sendlog = get_logger('clients.send')
-sendlog.debug('Logging location: %s' % DEBUG_LOG)
-add_file_logger('data.send', __name__, filename=DEBUG_LOG)
-datasendlog = get_logger('data.send')
-add_file_logger('clients.recv', __name__, filename=DEBUG_LOG)
-recvlog = get_logger('clients.recv')
-add_file_logger('data.recv', __name__, filename=DEBUG_LOG)
-datarecvlog = get_logger('data.recv')
+
+TIMEOUT = 60.0   # seconds
+HTTP_METHODS = ['GET', 'POST', 'PUT', 'HEAD', 'DELETE', 'COPY', 'MOVE']
+
+log = getLogger(__name__)
+sendlog = getLogger('%s.send' % __name__)
+recvlog = getLogger('%s.recv' % __name__)
+
+
+def _encode(v):
+    if v and isinstance(v, unicode):
+        return quote(v.encode('utf-8'))
+    return v
 
 
 class ClientError(Exception):
     def __init__(self, message, status=0, details=None):
+        log.debug('ClientError: msg[%s], sts[%s], dtl[%s]' % (
+            message,
+            status,
+            details))
         try:
             message += '' if message and message[-1] == '\n' else '\n'
             serv_stat, sep, new_msg = message.partition('{')
@@ -87,8 +96,213 @@ class ClientError(Exception):
             self.details = details if details else []
 
 
+class Logged(object):
+
+    LOG_TOKEN = False
+    LOG_DATA = False
+    LOG_PID = False
+    _token = None
+
+
+class RequestManager(Logged):
+    """Handle http request information"""
+
+    def _connection_info(self, url, path, params={}):
+        """ Set self.url to scheme://netloc/?params
+        :param url: (str or unicode) The service url
+
+        :param path: (str or unicode) The service path (url/path)
+
+        :param params: (dict) Parameters to add to final url
+
+        :returns: (scheme, netloc)
+        """
+        url = _encode(str(url)) if url else 'http://127.0.0.1/'
+        url += '' if url.endswith('/') else '/'
+        if path:
+            url += _encode(path[1:] if path.startswith('/') else path)
+        delim = '?'
+        for key, val in params.items():
+            val = '' if val in (None, False) else _encode(u'%s' % val)
+            url += '%s%s%s' % (delim, key, ('=%s' % val) if val else '')
+            delim = '&'
+        parsed = urlparse(url)
+        self.url = url
+        self.path = parsed.path or '/'
+        if parsed.query:
+            self.path += '?%s' % parsed.query
+        return (parsed.scheme, parsed.netloc)
+
+    def __init__(
+            self, method, url, path,
+            data=None, headers={}, params={}):
+        method = method.upper()
+        assert method in HTTP_METHODS, 'Invalid http method %s' % method
+        if headers:
+            assert isinstance(headers, dict)
+        self.headers = dict(headers)
+        self.method, self.data = method, data
+        self.scheme, self.netloc = self._connection_info(url, path, params)
+
+    def dump_log(self):
+        plog = '\t[%s]' if self.LOG_PID else ''
+        sendlog.info('- -  -   -     -        -             -')
+        sendlog.info('%s %s://%s%s%s' % (
+            self.method, self.scheme, self.netloc, self.path, plog))
+        for key, val in self.headers.items():
+            if key.lower() in ('x-auth-token', ) and not self.LOG_TOKEN:
+                self._token, val = val, '...'
+            sendlog.info('  %s: %s%s' % (key, val, plog))
+        if self.data:
+            sendlog.info('data size:%s%s' % (len(self.data), plog))
+            if self.LOG_DATA:
+                sendlog.info(self.data.replace(self._token, '...') if (
+                    self._token) else self.data)
+        else:
+            sendlog.info('data size:0%s' % plog)
+
+    def perform(self, conn):
+        """
+        :param conn: (httplib connection object)
+
+        :returns: (HTTPResponse)
+        """
+        self.dump_log()
+        conn.request(
+            method=str(self.method.upper()),
+            url=str(self.path),
+            headers=self.headers,
+            body=self.data)
+        sendlog.info('')
+        keep_trying = TIMEOUT
+        while keep_trying > 0:
+            try:
+                return conn.getresponse()
+            except ResponseNotReady:
+                wait = 0.03 * random()
+                sleep(wait)
+                keep_trying -= wait
+        plog = '\t[%s]' if self.LOG_PID else ''
+        logmsg = 'Kamaki Timeout %s %s%s' % (self.method, self.path, plog)
+        recvlog.debug(logmsg)
+        raise ClientError('HTTPResponse takes too long - kamaki timeout')
+
+
+class ResponseManager(Logged):
+    """Manage the http request and handle the response data, headers, etc."""
+
+    def __init__(self, request, poolsize=None, connection_retry_limit=0):
+        """
+        :param request: (RequestManager)
+
+        :param poolsize: (int) the size of the connection pool
+
+        :param connection_retry_limit: (int)
+        """
+        self.CONNECTION_TRY_LIMIT = 1 + connection_retry_limit
+        self.request = request
+        self._request_performed = False
+        self.poolsize = poolsize
+
+    def _get_response(self):
+        if self._request_performed:
+            return
+
+        pool_kw = dict(size=self.poolsize) if self.poolsize else dict()
+        for retries in range(1, self.CONNECTION_TRY_LIMIT + 1):
+            try:
+                with PooledHTTPConnection(
+                        self.request.netloc, self.request.scheme,
+                        **pool_kw) as connection:
+                    self.request.LOG_TOKEN = self.LOG_TOKEN
+                    self.request.LOG_DATA = self.LOG_DATA
+                    self.request.LOG_PID = self.LOG_PID
+                    r = self.request.perform(connection)
+                    plog = ''
+                    if self.LOG_PID:
+                        recvlog.info('\n%s <-- %s <-- [req: %s]\n' % (
+                            self, r, self.request))
+                        plog = '\t[%s]' % self
+                    self._request_performed = True
+                    self._status_code, self._status = r.status, unquote(
+                        r.reason)
+                    recvlog.info(
+                        '%d %s%s' % (
+                            self.status_code, self.status, plog))
+                    self._headers = dict()
+                    for k, v in r.getheaders():
+                        if k.lower in ('x-auth-token', ) and (
+                                not self.LOG_TOKEN):
+                            self._token, v = v, '...'
+                        v = unquote(v)
+                        self._headers[k] = v
+                        recvlog.info('  %s: %s%s' % (k, v, plog))
+                    self._content = r.read()
+                    recvlog.info('data size: %s%s' % (
+                        len(self._content) if self._content else 0, plog))
+                    if self.LOG_DATA and self._content:
+                        data = '%s%s' % (self._content, plog)
+                        if self._token:
+                            data = data.replace(self._token, '...')
+                        sendlog.info(data)
+                    sendlog.info('-             -        -     -   -  - -')
+                break
+            except Exception as err:
+                if isinstance(err, HTTPException):
+                    if retries >= self.CONNECTION_TRY_LIMIT:
+                        raise ClientError(
+                            'Connection to %s failed %s times (%s: %s )' % (
+                                self.request.url, retries, type(err), err))
+                else:
+                    from traceback import format_stack
+                    recvlog.debug(
+                        '\n'.join(['%s' % type(err)] + format_stack()))
+                    raise ClientError(
+                        'Failed while http-connecting to %s (%s)' % (
+                            self.request.url, err))
+
+    @property
+    def status_code(self):
+        self._get_response()
+        return self._status_code
+
+    @property
+    def status(self):
+        self._get_response()
+        return self._status
+
+    @property
+    def headers(self):
+        self._get_response()
+        return self._headers
+
+    @property
+    def content(self):
+        self._get_response()
+        return self._content
+
+    @property
+    def text(self):
+        """
+        :returns: (str) content
+        """
+        self._get_response()
+        return '%s' % self._content
+
+    @property
+    def json(self):
+        """
+        :returns: (dict) squeezed from json-formated content
+        """
+        self._get_response()
+        try:
+            return loads(self._content)
+        except ValueError as err:
+            raise ClientError('Response not formated in JSON - %s' % err)
+
+
 class SilentEvent(Thread):
-    """ Thread-run method(*args, **kwargs)"""
+    """Thread-run method(*args, **kwargs)"""
     def __init__(self, method, *args, **kwargs):
         super(self.__class__, self).__init__()
         self.method = method
@@ -115,18 +329,17 @@ class SilentEvent(Thread):
             self._exception = e
 
 
-class Client(object):
+class Client(Logged):
 
-    def __init__(self, base_url, token, http_client=KamakiHTTPConnection()):
+    MAX_THREADS = 7
+    DATE_FORMATS = ['%a %b %d %H:%M:%S %Y', ]
+    CONNECTION_RETRY_LIMIT = 0
+
+    def __init__(self, base_url, token):
+        assert base_url, 'No base_url for client %s' % self
         self.base_url = base_url
         self.token = token
-        self.headers = {}
-        self.DATE_FORMATS = [
-            '%a %b %d %H:%M:%S %Y',
-            '%A, %d-%b-%y %H:%M:%S GMT',
-            '%a, %d %b %Y %H:%M:%S GMT']
-        self.http_client = http_client
-        self.MAX_THREADS = 7
+        self.headers, self.params = dict(), dict()
 
     def _init_thread_limit(self, limit=1):
         assert isinstance(limit, int) and limit > 0, 'Thread limit not a +int'
@@ -156,7 +369,43 @@ class Client(object):
             return []
         return threadlist
 
+    def async_run(self, method, kwarg_list):
+        """Fire threads of operations
+
+        :param method: the method to run in each thread
+
+        :param kwarg_list: (list of dicts) the arguments to pass in each method
+            call
+
+        :returns: (list) the results of each method call w.r. to the order of
+            kwarg_list
+        """
+        flying, results = {}, {}
+        self._init_thread_limit()
+        for index, kwargs in enumerate(kwarg_list):
+            self._watch_thread_limit(flying.values())
+            flying[index] = SilentEvent(method=method, **kwargs)
+            flying[index].start()
+            unfinished = {}
+            for key, thread in flying.items():
+                if thread.isAlive():
+                    unfinished[key] = thread
+                elif thread.exception:
+                    raise thread.exception
+                else:
+                    results[key] = thread.value
+            flying = unfinished
+        sendlog.info('- - - wait for threads to finish')
+        for key, thread in flying.items():
+            if thread.isAlive():
+                thread.join()
+            if thread.exception:
+                raise thread.exception
+            results[key] = thread.value
+        return results.values()
+
     def _raise_for_status(self, r):
+        log.debug('raise err from [%s] of type[%s]' % (r, type(r)))
         status_msg = getattr(r, 'status', None) or ''
         try:
             message = '%s %s\n' % (status_msg, r.text)
@@ -168,92 +417,58 @@ class Client(object):
     def set_header(self, name, value, iff=True):
         """Set a header 'name':'value'"""
         if value is not None and iff:
-            self.http_client.set_header(name, value)
+            self.headers[name] = unicode(value)
 
     def set_param(self, name, value=None, iff=True):
         if iff:
-            self.http_client.set_param(name, value)
+            self.params[name] = unicode(value)
 
     def request(
-            self,
-            method,
-            path,
-            async_headers={},
-            async_params={},
+            self, method, path,
+            async_headers=dict(), async_params=dict(),
             **kwargs):
-        """In threaded/asynchronous requests, headers and params are not safe
-        Therefore, the standard self.set_header/param system can be used only
-        for headers and params that are common for all requests. All other
-        params and headers should passes as
-        @param async_headers
-        @async_params
-        E.g. in most queries the 'X-Auth-Token' header might be the same for
-        all, but the 'Range' header might be different from request to request.
+        """Commit an HTTP request to base_url/path
+        Requests are commited to and performed by Request/ResponseManager
+        These classes perform a lazy http request. Present method, by default,
+        enforces them to perform the http call. Hint: call present method with
+        success=None to get a non-performed ResponseManager object.
         """
         assert isinstance(method, str) or isinstance(method, unicode)
         assert method
         assert isinstance(path, str) or isinstance(path, unicode)
         try:
+            headers = dict(self.headers)
+            headers.update(async_headers)
+            params = dict(self.params)
+            params.update(async_params)
             success = kwargs.pop('success', 200)
             data = kwargs.pop('data', None)
-            self.http_client.headers.setdefault('X-Auth-Token', self.token)
-
+            headers.setdefault('X-Auth-Token', self.token)
             if 'json' in kwargs:
                 data = dumps(kwargs.pop('json'))
-                self.http_client.headers.setdefault(
-                    'Content-Type',
-                    'application/json')
-            if data:
-                self.http_client.headers.setdefault(
-                    'Content-Length',
-                    '%s' % len(data))
-
-            sendlog.info('perform a %s @ %s', method, self.base_url)
-
-            self.http_client.url = self.base_url
-            self.http_client.path = quote(path.encode('utf8'))
-            r = self.http_client.perform_request(
-                method,
-                data,
-                async_headers,
-                async_params)
-
-            req = self.http_client
-            sendlog.info('%s %s', method, req.url)
-            headers = dict(req.headers)
-            headers.update(async_headers)
-
-            for key, val in headers.items():
-                sendlog.info('\t%s: %s', key, val)
-            sendlog.info('')
+                headers.setdefault('Content-Type', 'application/json')
             if data:
-                datasendlog.info(data)
-
-            recvlog.info('%d %s', r.status_code, r.status)
-            for key, val in r.headers.items():
-                recvlog.info('%s: %s', key, val)
-            if r.content:
-                datarecvlog.info(r.content)
-
-        except (KamakiResponseError, KamakiConnectionError) as err:
-            from traceback import format_stack
-            recvlog.debug('\n'.join(['%s' % type(err)] + format_stack()))
-            self.http_client.reset_headers()
-            self.http_client.reset_params()
-            errstr = '%s' % err
-            if not errstr:
-                errstr = ('%s' % type(err))[7:-2]
-            status = getattr(err, 'status', getattr(err, 'errno', 0))
-            raise ClientError('%s\n' % errstr, status=status)
+                headers.setdefault('Content-Length', '%s' % len(data))
+
+            plog = '\t[%s]' if self.LOG_PID else ''
+            sendlog.debug('\n\nCMT %s@%s%s', method, self.base_url, plog)
+            req = RequestManager(
+                method, self.base_url, path,
+                data=data, headers=headers, params=params)
+            #  req.log()
+            r = ResponseManager(
+                req, connection_retry_limit=self.CONNECTION_RETRY_LIMIT)
+            r.LOG_TOKEN, r.LOG_DATA, r.LOG_PID = (
+                self.LOG_TOKEN, self.LOG_DATA, self.LOG_PID)
+            r._token = headers['X-Auth-Token']
         finally:
-            self.http_client.reset_headers()
-            self.http_client.reset_params()
+            self.headers = dict()
+            self.params = dict()
 
         if success is not None:
             # Success can either be an int or a collection
             success = (success,) if isinstance(success, int) else success
             if r.status_code not in success:
-                r.release()
                 self._raise_for_status(r)
         return r