Merged Trevor's tree

1 files changed, 446 insertions, 0 deletions

diff --git a/libbe/storage/http.py b/libbe/storage/http.py
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+# Copyright (C) 2010 W. Trevor King <wking@drexel.edu>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+# For urllib2 information, see
+#   urllib2, from urllib2 - The Missing Manual
+#   http://www.voidspace.org.uk/python/articles/urllib2.shtml
+# 
+# A dictionary of response codes is available in
+#   httplib.responses
+
+"""Define an HTTP-based :class:`~libbe.storage.base.VersionedStorage`
+implementation.
+
+See Also
+--------
+:mod:`libbe.command.serve` : the associated server
+
+"""
+
+import sys
+import urllib
+import urllib2
+import urlparse
+
+import libbe
+import libbe.version
+import base
+from libbe import TESTING
+
+if TESTING == True:
+    import copy
+    import doctest
+    import StringIO
+    import unittest
+
+    import libbe.bugdir
+    import libbe.command.serve
+
+
+USER_AGENT = 'BE-HTTP-Storage'
+HTTP_OK = 200
+HTTP_FOUND = 302
+HTTP_TEMP_REDIRECT = 307
+HTTP_USER_ERROR = 418
+"""Status returned to indicate exceptions on the server side.
+
+A BE-specific extension to the HTTP/1.1 protocol (See `RFC 2616`_).
+
+.. _RFC 2616: http://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html#sec6.1.1
+"""
+
+HTTP_VALID = [HTTP_OK, HTTP_FOUND, HTTP_TEMP_REDIRECT, HTTP_USER_ERROR]
+
+class InvalidURL (Exception):
+    def __init__(self, error=None, url=None, msg=None):
+        Exception.__init__(self, msg)
+        self.url = url
+        self.error = error
+        self.msg = msg
+    def __str__(self):
+        if self.msg == None:
+            if self.error == None:
+                return "Unknown URL error: %s" % self.url
+            return self.error.__str__()
+        return self.msg
+
+def get_post_url(url, get=True, data_dict=None, headers=[]):
+    """Execute a GET or POST transaction.
+
+    Parameters
+    ----------
+    url : str
+      The base URL (query portion added internally, if necessary).
+    get : bool
+      Use GET if True, otherwise use POST.
+    data_dict : dict
+      Data to send, either by URL query (if GET) or by POST (if POST).
+    headers : list
+      Extra HTTP headers to add to the request.
+    """
+    if data_dict == None:
+        data_dict = {}
+    if get == True:
+        if data_dict != {}:
+            # encode get parameters in the url
+            param_string = urllib.urlencode(data_dict)
+            url = "%s?%s" % (url, param_string)
+        data = None
+    else:
+        data = urllib.urlencode(data_dict)
+    headers = dict(headers)
+    headers['User-Agent'] = USER_AGENT
+    req = urllib2.Request(url, data=data, headers=headers)
+    try:
+        response = urllib2.urlopen(req)
+    except urllib2.HTTPError, e:
+        if hasattr(e, 'reason'):
+            msg = 'We failed to reach a server.\nURL: %s\nReason: %s' \
+                % (url, e.reason)
+        elif hasattr(e, 'code'):
+            msg = "The server couldn't fulfill the request.\nURL: %s\nError code: %s" \
+                % (url, e.code)
+        raise InvalidURL(error=e, url=url, msg=msg)
+    page = response.read()
+    final_url = response.geturl()
+    info = response.info()
+    response.close()
+    return (page, final_url, info)
+
+
+class HTTP (base.VersionedStorage):
+    """:class:`~libbe.storage.base.VersionedStorage` implementation over
+    HTTP.
+
+    Uses GET to retrieve information and POST to set information.
+    """
+    name = 'HTTP'
+
+    def __init__(self, repo, *args, **kwargs):
+        repo,self.uname,self.password = self.parse_repo(repo)
+        base.VersionedStorage.__init__(self, repo, *args, **kwargs)
+
+    def parse_repo(self, repo):
+        """Grab username and password (if any) from the repo URL.
+
+        Examples
+        --------
+
+        >>> s = HTTP('http://host.com/path/to/repo')
+        >>> s.repo
+        'http://host.com/path/to/repo'
+        >>> s.uname == None
+        True
+        >>> s.password == None
+        True
+        >>> s.parse_repo('http://joe:secret@host.com/path/to/repo')
+        ('http://host.com/path/to/repo', 'joe', 'secret')
+        """
+        scheme,netloc,path,params,query,fragment = urlparse.urlparse(repo)
+        parts = netloc.split('@', 1)
+        if len(parts) == 2:
+            uname,password = parts[0].split(':')
+            repo = urlparse.urlunparse(
+                (scheme, parts[1], path, params, query, fragment))
+        else:
+            uname,password = (None, None)
+        return (repo, uname, password)
+
+    def get_post_url(self, url, get=True, data_dict=None, headers=[]):
+        if self.uname != None and self.password != None:
+            headers.append(('Authorization','Basic %s' % \
+                ('%s:%s' % (self.uname, self.password)).encode('base64')))
+        return get_post_url(url, get, data_dict, headers)
+
+    def storage_version(self, revision=None):
+        """Return the storage format for this backend."""
+        return libbe.storage.STORAGE_VERSION
+
+    def _init(self):
+        """Create a new storage repository."""
+        raise base.NotSupported(
+            'init', 'Cannot initialize this repository format.')
+
+    def _destroy(self):
+        """Remove the storage repository."""
+        raise base.NotSupported(
+            'destroy', 'Cannot destroy this repository format.')
+
+    def _connect(self):
+        self.check_storage_version()
+
+    def _disconnect(self):
+        pass
+
+    def _add(self, id, parent=None, directory=False):
+        url = urlparse.urljoin(self.repo, 'add')
+        page,final_url,info = self.get_post_url(
+            url, get=False,
+            data_dict={'id':id, 'parent':parent, 'directory':directory})
+
+    def _exists(self, id, revision=None):
+        url = urlparse.urljoin(self.repo, 'exists')
+        page,final_url,info = self.get_post_url(
+            url, get=True,
+            data_dict={'id':id, 'revision':revision})
+        if page == 'True':
+            return True
+        return False
+
+    def _remove(self, id):
+        url = urlparse.urljoin(self.repo, 'remove')
+        page,final_url,info = self.get_post_url(
+            url, get=False,
+            data_dict={'id':id, 'recursive':False})
+
+    def _recursive_remove(self, id):
+        url = urlparse.urljoin(self.repo, 'remove')
+        page,final_url,info = self.get_post_url(
+            url, get=False,
+            data_dict={'id':id, 'recursive':True})
+
+    def _ancestors(self, id=None, revision=None):
+        url = urlparse.urljoin(self.repo, 'ancestors')
+        page,final_url,info = self.get_post_url(
+            url, get=True,
+            data_dict={'id':id, 'revision':revision})
+        return page.strip('\n').splitlines()
+
+    def _children(self, id=None, revision=None):
+        url = urlparse.urljoin(self.repo, 'children')
+        page,final_url,info = self.get_post_url(
+            url, get=True,
+            data_dict={'id':id, 'revision':revision})
+        return page.strip('\n').splitlines()
+
+    def _get(self, id, default=base.InvalidObject, revision=None):
+        url = urlparse.urljoin(self.repo, '/'.join(['get', id]))
+        try:
+            page,final_url,info = self.get_post_url(
+                url, get=True,
+                data_dict={'revision':revision})
+        except InvalidURL, e:
+            if not (hasattr(e.error, 'code') and e.error.code in HTTP_VALID):
+                raise
+            elif default == base.InvalidObject:
+                raise base.InvalidID(id)
+            return default
+        version = info['X-BE-Version']
+        if version != libbe.storage.STORAGE_VERSION:
+            raise base.InvalidStorageVersion(
+                version, libbe.storage.STORAGE_VERSION)
+        return page
+
+    def _set(self, id, value):
+        url = urlparse.urljoin(self.repo, '/'.join(['set', id]))
+        try:
+            page,final_url,info = self.get_post_url(
+                url, get=False,
+                data_dict={'value':value})
+        except InvalidURL, e:
+            if not (hasattr(e.error, 'code') and e.error.code in HTTP_VALID):
+                raise
+            if e.error.code == HTTP_USER_ERROR \
+                    and not 'InvalidID' in str(e.error):
+                raise base.InvalidDirectory(
+                    'Directory %s cannot have data' % id)
+            raise base.InvalidID(id)
+
+    def _commit(self, summary, body=None, allow_empty=False):
+        url = urlparse.urljoin(self.repo, 'commit')
+        try:
+            page,final_url,info = self.get_post_url(
+                url, get=False,
+                data_dict={'summary':summary, 'body':body,
+                           'allow_empty':allow_empty})
+        except InvalidURL, e:
+            if not (hasattr(e.error, 'code') and e.error.code in HTTP_VALID):
+                raise
+            if e.error.code == HTTP_USER_ERROR:
+                raise base.EmptyCommit
+            raise base.InvalidID(id)
+        return page.rstrip('\n')
+
+    def revision_id(self, index=None):
+        """Return the name of the <index>th revision.
+
+        The choice of which branch to follow when crossing
+        branches/merges is not defined.  Revision indices start at 1;
+        ID 0 is the blank repository.
+
+        Return None if index==None.
+
+        Raises
+        ------
+        InvalidRevision
+          If the specified revision does not exist.
+        """
+        if index == None:
+            return None
+        try:
+            if int(index) != index:
+                raise base.InvalidRevision(index)
+        except ValueError:
+            raise base.InvalidRevision(index)
+        url = urlparse.urljoin(self.repo, 'revision-id')
+        try:
+            page,final_url,info = self.get_post_url(
+                url, get=True,
+                data_dict={'index':index})
+        except InvalidURL, e:
+            if not (hasattr(e.error, 'code') and e.error.code in HTTP_VALID):
+                raise
+            if e.error.code == HTTP_USER_ERROR:
+                raise base.InvalidRevision(index)
+            raise base.InvalidID(id)
+        return page.rstrip('\n')
+
+    def changed(self, revision=None):
+        url = urlparse.urljoin(self.repo, 'changed')
+        page,final_url,info = self.get_post_url(
+            url, get=True,
+            data_dict={'revision':revision})
+        lines = page.strip('\n')
+        new,mod,rem = [p.splitlines() for p in page.split('\n\n')]
+        return (new, mod, rem)
+
+    def check_storage_version(self):
+        version = self.storage_version()
+        if version != libbe.storage.STORAGE_VERSION:
+            raise base.InvalidStorageVersion(
+                version, libbe.storage.STORAGE_VERSION)
+
+    def storage_version(self, revision=None):
+        url = urlparse.urljoin(self.repo, 'version')
+        page,final_url,info = self.get_post_url(
+            url, get=True, data_dict={'revision':revision})
+        return page.rstrip('\n')
+
+if TESTING == True:
+    class GetPostUrlTestCase (unittest.TestCase):
+        """Test cases for get_post_url()"""
+        def test_get(self):
+            url = 'http://bugseverywhere.org/be/show/HomePage'
+            page,final_url,info = get_post_url(url=url)
+            self.failUnless(final_url == url,
+                'Redirect?\n  Expected: "%s"\n  Got:      "%s"'
+                % (url, final_url))
+        def test_get_redirect(self):
+            url = 'http://bugseverywhere.org'
+            expected = 'http://bugseverywhere.org/be/show/HomePage'
+            page,final_url,info = get_post_url(url=url)
+            self.failUnless(final_url == expected,
+                'Redirect?\n  Expected: "%s"\n  Got:      "%s"'
+                % (expected, final_url))
+
+    class TestingHTTP (HTTP):
+        name = 'TestingHTTP'
+        def __init__(self, repo, *args, **kwargs):
+            self._storage_backend = base.VersionedStorage(repo)
+            self.app = libbe.command.serve.ServerApp(
+                storage=self._storage_backend)
+            HTTP.__init__(self, repo='http://localhost:8000/', *args, **kwargs)
+            self.intitialized = False
+            # duplicated from libbe.storage.serve.WSGITestCase
+            self.default_environ = {
+                'REQUEST_METHOD': 'GET', # 'POST', 'HEAD'
+                'SCRIPT_NAME':'',
+                'PATH_INFO': '',
+                #'QUERY_STRING':'',   # may be empty or absent
+                #'CONTENT_TYPE':'',   # may be empty or absent
+                #'CONTENT_LENGTH':'', # may be empty or absent
+                'SERVER_NAME':'example.com',
+                'SERVER_PORT':'80',
+                'SERVER_PROTOCOL':'HTTP/1.1',
+                'wsgi.version':(1,0),
+                'wsgi.url_scheme':'http',
+                'wsgi.input':StringIO.StringIO(),
+                'wsgi.errors':StringIO.StringIO(),
+                'wsgi.multithread':False,
+                'wsgi.multiprocess':False,
+                'wsgi.run_once':False,
+                }
+        def getURL(self, app, path='/', method='GET', data=None,
+                   scheme='http', environ={}):
+            # duplicated from libbe.storage.serve.WSGITestCase
+            env = copy.copy(self.default_environ)
+            env['PATH_INFO'] = path
+            env['REQUEST_METHOD'] = method
+            env['scheme'] = scheme
+            if data != None:
+                enc_data = urllib.urlencode(data)
+                if method == 'POST':
+                    env['CONTENT_LENGTH'] = len(enc_data)
+                    env['wsgi.input'] = StringIO.StringIO(enc_data)
+                else:
+                    assert method in ['GET', 'HEAD'], method
+                    env['QUERY_STRING'] = enc_data
+            for key,value in environ.items():
+                env[key] = value
+            return ''.join(app(env, self.start_response))
+        def start_response(self, status, response_headers, exc_info=None):
+            self.status = status
+            self.response_headers = response_headers
+            self.exc_info = exc_info
+        def get_post_url(self, url, get=True, data_dict=None, headers=[]):
+            if get == True:
+                method = 'GET'
+            else:
+                method = 'POST'
+            scheme,netloc,path,params,query,fragment = urlparse.urlparse(url)
+            environ = {}
+            for header_name,header_value in headers:
+                environ['HTTP_%s' % header_name] = header_value
+            output = self.getURL(
+                self.app, path, method, data_dict, scheme, environ)
+            if self.status != '200 OK':
+                class __estr (object):
+                    def __init__(self, string):
+                        self.string = string
+                        self.code = int(string.split()[0])
+                    def __str__(self):
+                        return self.string
+                error = __estr(self.status)
+                raise InvalidURL(error=error, url=url, msg=output)
+            info = dict(self.response_headers)
+            return (output, url, info)
+        def _init(self):
+            try:
+                HTTP._init(self)
+                raise AssertionError
+            except base.NotSupported:
+                pass
+            self._storage_backend._init()
+        def _destroy(self):
+            try:
+                HTTP._destroy(self)
+                raise AssertionError
+            except base.NotSupported:
+                pass
+            self._storage_backend._destroy()
+        def _connect(self):
+            self._storage_backend._connect()
+            HTTP._connect(self)
+        def _disconnect(self):
+            HTTP._disconnect(self)
+            self._storage_backend._disconnect()
+
+
+    base.make_versioned_storage_testcase_subclasses(
+        TestingHTTP, sys.modules[__name__])
+
+    unitsuite =unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
+    suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])