Add a simple prototype data store

6 files changed, 600 insertions, 1 deletions

diff --git a/services/Makefile.am b/services/Makefile.am
index 2a0fe5a..9cf9b95 100644
--- a/services/Makefile.am
+++ b/services/Makefile.am
@@ -1 +1 @@
-SUBDIRS = presence nm clipboard
+SUBDIRS = presence nm clipboard datastore
diff --git a/services/datastore/Makefile.am b/services/datastore/Makefile.am
new file mode 100644
index 0000000..e98a34b
--- /dev/null
+++ b/services/datastore/Makefile.am
@@ -0,0 +1,12 @@
+sugardir = $(pkgdatadir)/services/data-store
+sugar_PYTHON =      \
+	__init__.py     \
+	datastore.py    \
+	dbus_helpers.py
+
+bin_SCRIPTS = sugar-data-store
+
+dbusservicedir = $(sysconfdir)/dbus-1/system.d/
+dbusservice_DATA = sugar-data-store.conf
+
+EXTRA_DIST = $(dbusservice_DATA) $(bin_SCRIPTS)
diff --git a/services/datastore/__init__.py b/services/datastore/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/services/datastore/__init__.py
diff --git a/services/datastore/datastore.py b/services/datastore/datastore.py
new file mode 100644
index 0000000..92270e4
--- /dev/null
+++ b/services/datastore/datastore.py
@@ -0,0 +1,333 @@
+#!/bin/python
+# Copyright (C) 2006, Red Hat, Inc.
+#
+# 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 St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import os
+import dbus, dbus.glib, gobject
+import logging
+import sqlite
+import dbus_helpers
+
+have_sugar = False
+try:
+    from sugar import env
+    have_sugar = True
+except ImportError:
+    pass
+
+
+_DS_SERVICE = "org.laptop.sugar.DataStore"
+_DS_DBUS_INTERFACE = "org.laptop.sugar.DataStore"
+_DS_OBJECT_PATH = "/org/laptop/sugar/DataStore"
+
+_DS_OBJECT_DBUS_INTERFACE = "org.laptop.sugar.DataStore.Object"
+_DS_OBJECT_OBJECT_PATH = "/org/laptop/sugar/DataStore/Object"
+
+class NotFoundError(Exception):
+    pass
+
+def _create_op(uid):
+    return "%s/%d" % (_DS_OBJECT_OBJECT_PATH, uid)
+
+def _get_uid_from_op(op):
+    if not op.startswith(_DS_OBJECT_OBJECT_PATH + "/"):
+        raise ValueError("Invalid object path %s." % op)
+    item = op[len(_DS_OBJECT_OBJECT_PATH + "/"):]
+    return int(item)
+
+def _get_data_as_string(data):
+    if isinstance(data, list):
+        data_str = ""
+        for item in data:
+            data_str += chr(item)
+        return data_str
+    elif isinstance(data, int):
+        return str(data)
+    elif isinstance(data, str):
+        return data
+    elif isinstance(data, unicode):
+        return str(data)
+    else:
+        raise ValueError("Unsupported data type")
+
+class DataStoreDBusHelper(dbus.service.Object):
+    def __init__(self, parent, bus_name):
+        self._parent = parent
+        self._bus_name = bus_name
+        dbus.service.Object.__init__(self, bus_name, _DS_OBJECT_PATH)
+
+    @dbus.service.method(_DS_DBUS_INTERFACE,
+                        in_signature="x", out_signature="o")
+    def get(self, uid):
+        uid = self._parent.get(uid)
+        return self._create_op(uid)
+
+    @dbus.service.method(_DS_DBUS_INTERFACE,
+                        in_signature="aya{sv}", out_signature="o")
+    def create(self, data, prop_dict):
+        uid = self._parent.create(data, prop_dict)
+        return _create_op(uid)
+
+    @dbus.service.method(_DS_DBUS_INTERFACE,
+                        in_signature="o", out_signature="i")
+    def delete(self, op):
+        uid = _get_uid_from_op(op)
+        self._parent.delete(uid)
+        return 0
+
+    @dbus.service.method(_DS_DBUS_INTERFACE,
+                        in_signature="a{sv}", out_signature="ao")
+    def find(self, prop_dict):
+        uids = self._parent.find(prop_dict)
+        ops = []
+        for uid in uids:
+            ops.append(_create_op(uid))
+        return ops
+
+class ObjectDBusHelper(dbus_helpers.FallbackObject):
+    def __init__(self, parent, bus_name):
+        self._parent = parent
+        self._bus_name = bus_name
+        dbus_helpers.FallbackObject.__init__(self, bus_name, _DS_OBJECT_OBJECT_PATH)
+
+    @dbus_helpers.method(_DS_OBJECT_DBUS_INTERFACE,
+                         in_signature="", out_signature="ay", dbus_message_keyword="dbus_message")
+    def get_data(self, dbus_message=None):
+        if not dbus_message:
+            raise RuntimeError("Need the dbus message.")
+        uid = _get_uid_from_op(dbus_message.get_path())
+        return self._parent.get_data(uid)
+
+    @dbus_helpers.method(_DS_OBJECT_DBUS_INTERFACE,
+                         in_signature="ay", out_signature="i", dbus_message_keyword="dbus_message")
+    def set_data(self, data, dbus_message=None):
+        if not dbus_message:
+            raise RuntimeError("Need the dbus message.")
+        uid = _get_uid_from_op(dbus_message.get_path())
+        self._parent.set_data(uid, data)
+        return 0
+
+    @dbus_helpers.method(_DS_OBJECT_DBUS_INTERFACE,
+                         in_signature="as", out_signature="a{sv}", dbus_message_keyword="dbus_message")
+    def get_properties(self, keys, dbus_message=None):
+        if not dbus_message:
+            raise RuntimeError("Need the dbus message.")
+        uid = _get_uid_from_op(dbus_message.get_path())
+        return self._parent.get_properties(uid, keys)
+
+    @dbus_helpers.method(_DS_OBJECT_DBUS_INTERFACE,
+                         in_signature="a{sv}", out_signature="i", dbus_message_keyword="dbus_message")
+    def set_properties(self, prop_dict, dbus_message=None):
+        if not dbus_message:
+            raise RuntimeError("Need the dbus message.")
+        uid = _get_uid_from_op(dbus_message.get_path())
+        self._parent.set_properties(uid, prop_dict)
+        return 0
+
+    @dbus_helpers.fallback_signal(_DS_OBJECT_DBUS_INTERFACE,
+                                  signature="ba{sv}b", ignore_args=["uid"])
+    def Updated(self, data, prop_dict, deleted, uid=None):
+        # Return the object path so the signal decorator knows what
+        # object this signal should be fore
+        if not uid:
+            raise RuntimeError("Need a UID.")
+        op = _create_op(uid)
+        return op
+
+class DataStore(object):
+    def __init__(self):
+        self._session_bus = dbus.SessionBus()
+        self._bus_name = dbus.service.BusName(_DS_SERVICE, bus=self._session_bus)        
+        self._dbus_helper = DataStoreDBusHelper(self, self._bus_name)
+        self._dbus_obj_helper = ObjectDBusHelper(self, self._bus_name)
+
+        ppath = "/tmp"
+        if have_sugar:
+            ppath = env.get_profile_path()
+        self._dbfile = os.path.join(ppath, "ds", "data-store.db")
+        if not os.path.exists(os.path.dirname(self._dbfile)):
+            os.makedirs(os.path.dirname(self._dbfile), 0755)
+
+        self._dbcx = sqlite.connect(self._dbfile, encoding="utf-8", timeout=3)
+        try:
+            self._ensure_table()
+        except StandardError, e:
+            logging.info("Could not access the data store.  Reason: '%s'.  Exiting..." % e)
+            os._exit(1)
+
+    def __del__(self):
+        self._dbcx.close()
+        del self._dbcx
+
+    def _ensure_table(self):
+        curs = self._dbcx.cursor()
+        try:
+            curs.execute('SELECT * FROM properties LIMIT 4')
+            self._dbcx.commit()
+        except Exception, e:
+            # If table wasn't created, try to create it
+            self._dbcx.commit()
+            curs.execute('CREATE TABLE objects (' \
+                'uid INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, ' \
+                'data BLOB' \
+                ');')
+            curs.execute('CREATE TABLE properties (' \
+                'objid INTEGER NOT NULL, '           \
+                'key VARCHAR(100),'                  \
+                'value VARCHAR(200)'                 \
+                ');')
+            curs.execute('CREATE INDEX objid_idx ON properties(objid);')
+            self._dbcx.commit()
+        del curs
+
+    def get(self, uid):
+        curs = self._dbcx.cursor()
+        curs.execute('SELECT uid FROM objects WHERE uid=%d;' % uid)
+        res = curs.fetchall()
+        self._dbcx.commit()
+        del curs
+        if len(res) > 0:
+            return uid
+        raise NotFoundError("Object %d was not found." % uid)
+
+    def create(self, data, prop_dict=None):
+        curs = self._dbcx.cursor()
+        curs.execute("INSERT INTO objects (uid) VALUES (NULL);")
+        curs.execute("SELECT last_insert_rowid();")
+        rows = curs.fetchall()
+        self._dbcx.commit()
+        last_row = rows[0]
+        uid = last_row[0]
+        for (key, value) in prop_dict.items():
+            safe_key = key.replace("'", "''")
+            value = str(value)
+            curs.execute("INSERT INTO properties (objid, key, value) VALUES (%d, '%s', '%s');" % (uid, safe_key, sqlite.encode(value)))
+        self._dbcx.commit()
+        del curs
+        return uid
+
+    def delete(self, uid):
+        curs = self._dbcx.cursor()
+        curs.execute("DELETE FROM objects WHERE (uid=%d);" % uid)
+        curs.execute("DELETE FROM properties WHERE (objid=%d);" % uid)
+        self._dbcx.commit()
+        del curs
+        self._dbus_obj_helper.Updated(False, {}, True, uid=uid)
+        return 0
+
+    def find(self, prop_dict):
+        query = "SELECT objid FROM properties WHERE ("
+        subquery = ""
+        for (key, value) in prop_dict.items():
+            safe_key = key.replace("'", "''")
+            value = str(value)
+            substr = "key='%s' AND value='%s'" % (safe_key, sqlite.encode(value))
+            if len(subquery) > 0:
+                subquery += " AND"
+            subquery += substr
+        query += subquery + ")"
+        curs = self._dbcx.cursor()
+        curs.execute(query)
+        rows = curs.fetchall()
+        self._dbcx.commit()
+        # FIXME: ensure that each properties.objid has a match in objects.uid
+        uids = []
+        for row in rows:
+            uids.append(row['objid'])
+        del curs
+        return uids
+
+    def set_data(self, uid, data):
+        curs = self._dbcx.cursor()
+        curs.execute('SELECT uid FROM objects WHERE uid=%d;' % uid)
+        res = curs.fetchall()
+        self._dbcx.commit()
+        if len(res) <= 0:
+            del curs
+            raise NotFoundError("Object %d was not found." % uid)
+        data = _get_data_as_string(data)
+        curs.execute("UPDATE objects SET data='%s' WHERE uid=%d;" % (sqlite.encode(data), uid))
+        self._dbcx.commit()
+        del curs
+        self._dbus_obj_helper.Updated(True, {}, False, uid=uid)
+
+    _reserved_keys = ["uid", "objid", "data", "created", "modified"]
+    def set_properties(self, uid, prop_dict):
+        curs = self._dbcx.cursor()
+        curs.execute('SELECT uid FROM objects WHERE uid=%d;' % uid)
+        res = curs.fetchall()
+        self._dbcx.commit()
+        if len(res) <= 0:
+            del curs
+            raise NotFoundError("Object %d was not found." % uid)
+
+        for key in prop_dict.keys():
+            if key in self._reserved_keys:
+                raise ValueError("key %s is a reserved key." % key)
+
+        for (key, value) in prop_dict.items():
+            safe_key = key.replace("'", "''")
+            enc_value = sqlite.encode(_get_data_as_string(value))
+            curs.execute("SELECT objid FROM properties WHERE (objid=%d AND key='%s');" % (uid, safe_key))
+            if len(curs.fetchall()) > 0:
+                curs.execute("UPDATE properties SET value='%s' WHERE (objid=%d AND key='%s');" % (enc_value, uid, safe_key))
+            else:
+                curs.execute("INSERT INTO properties (objid, key, value) VALUES (%d, '%s', '%s');" % (uid, safe_key, enc_value))
+        self._dbcx.commit()
+        del curs
+        self._dbus_obj_helper.Updated(False, {}, False, uid=uid)
+
+    def get_data(self, uid):
+        curs = self._dbcx.cursor()
+        curs.execute('SELECT uid, data FROM objects WHERE uid=%d;' % uid)
+        res = curs.fetchall()
+        self._dbcx.commit()
+        del curs
+        if len(res) <= 0:
+            raise NotFoundError("Object %d was not found." % uid)
+        return sqlite.decode(res[0]['data'])
+
+    def get_properties(self, uid, keys):
+        query = "SELECT objid, key, value FROM properties WHERE (objid=%d AND (" % uid
+        subquery = ""
+        for key in keys:
+            if len(subquery) > 0:
+                subquery += " OR "
+            safe_key = key.replace("'", "''")
+            subquery += "key='%s'" % safe_key
+        query += subquery + "));"
+        curs = self._dbcx.cursor()
+        curs.execute(query)
+        rows = curs.fetchall()
+        self._dbcx.commit()
+        prop_dict = {}
+        for row in rows:
+            conv_key = row['key'].replace("''", "'")
+            prop_dict[conv_key] = row['value']
+        del curs
+        return prop_dict
+
+
+def main():
+    loop = gobject.MainLoop()
+    ds = DataStore()
+    try:
+        loop.run()
+    except KeyboardInterrupt:
+        print 'Ctrl+C pressed, exiting...'
+
+if __name__ == "__main__":
+    main()
diff --git a/services/datastore/dbus_helpers.py b/services/datastore/dbus_helpers.py
new file mode 100644
index 0000000..391e201
--- /dev/null
+++ b/services/datastore/dbus_helpers.py
@@ -0,0 +1,222 @@
+# Copyright (C) 2006, Red Hat, Inc.
+#
+# 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 St, Fifth Floor, Boston, MA  02110-1301  USA
+
+
+# Mostly taken from dbus-python's service.py
+
+import dbus
+from dbus import service
+import inspect
+
+def method(dbus_interface, in_signature=None, out_signature=None, async_callbacks=None, sender_keyword=None, dbus_message_keyword=None):
+    dbus._util._validate_interface_or_name(dbus_interface)
+
+    def decorator(func):
+        args = inspect.getargspec(func)[0]
+        args.pop(0)
+
+        if async_callbacks:
+            if type(async_callbacks) != tuple:
+                raise TypeError('async_callbacks must be a tuple of (keyword for return callback, keyword for error callback)')
+            if len(async_callbacks) != 2:
+                raise ValueError('async_callbacks must be a tuple of (keyword for return callback, keyword for error callback)')
+            args.remove(async_callbacks[0])
+            args.remove(async_callbacks[1])
+
+        if sender_keyword:
+            args.remove(sender_keyword)
+
+        if dbus_message_keyword:
+            args.remove(dbus_message_keyword)
+
+        if in_signature:
+            in_sig = tuple(dbus.dbus_bindings.Signature(in_signature))
+
+            if len(in_sig) > len(args):
+                raise ValueError, 'input signature is longer than the number of arguments taken'
+            elif len(in_sig) < len(args):
+                raise ValueError, 'input signature is shorter than the number of arguments taken'
+
+        func._dbus_message_keyword = dbus_message_keyword
+        func._dbus_is_method = True
+        func._dbus_async_callbacks = async_callbacks
+        func._dbus_interface = dbus_interface
+        func._dbus_in_signature = in_signature
+        func._dbus_out_signature = out_signature
+        func._dbus_sender_keyword = sender_keyword
+        func._dbus_args = args
+        return func
+
+    return decorator
+
+def fallback_signal(dbus_interface, signature=None, ignore_args=None):
+    dbus._util._validate_interface_or_name(dbus_interface)
+    def decorator(func):
+        def emit_signal(self, *args, **keywords):
+            obj_path = func(self, *args, **keywords)
+            message = dbus.dbus_bindings.Signal(obj_path, dbus_interface, func.__name__)
+            iter = message.get_iter(True)
+
+            if emit_signal._dbus_signature:
+                signature = tuple(dbus.dbus_bindings.Signature(emit_signal._dbus_signature))
+                for (arg, sig) in zip(args, signature):
+                    iter.append_strict(arg, sig)
+            else:
+                for arg in args:
+                    iter.append(arg)
+
+            self._connection.send(message)
+
+        temp_args = inspect.getargspec(func)[0]
+        temp_args.pop(0)
+
+        args = []
+        for arg in temp_args:
+            if arg not in ignore_args:
+                args.append(arg)
+
+        if signature:
+            sig = tuple(dbus.dbus_bindings.Signature(signature))
+
+            if len(sig) > len(args):
+                raise ValueError, 'signal signature is longer than the number of arguments provided'
+            elif len(sig) < len(args):
+                raise ValueError, 'signal signature is shorter than the number of arguments provided'
+
+        emit_signal.__name__ = func.__name__
+        emit_signal.__doc__ = func.__doc__
+        emit_signal._dbus_is_signal = True
+        emit_signal._dbus_interface = dbus_interface
+        emit_signal._dbus_signature = signature
+        emit_signal._dbus_args = args
+        return emit_signal
+
+    return decorator
+
+class FallbackObject(dbus.service.Object):
+    """A base class for exporting your own Objects across the Bus.
+
+    Just inherit from Object and provide a list of methods to share
+    across the Bus
+    """
+    def __init__(self, bus_name, fallback_object_path):
+        self._object_path = fallback_object_path
+        self._name = bus_name 
+        self._bus = bus_name.get_bus()
+            
+        self._connection = self._bus.get_connection()
+
+        self._connection.register_fallback(fallback_object_path, self._unregister_cb, self._message_cb)
+
+    def _message_cb(self, connection, message):
+        try:
+            # lookup candidate method and parent method
+            method_name = message.get_member()
+            interface_name = message.get_interface()
+            (candidate_method, parent_method) = dbus.service._method_lookup(self, method_name, interface_name)
+
+            # set up method call parameters
+            args = message.get_args_list()
+            keywords = {}
+
+            # iterate signature into list of complete types
+            if parent_method._dbus_out_signature:
+                signature = tuple(dbus.dbus_bindings.Signature(parent_method._dbus_out_signature))
+            else:
+                signature = None
+
+            # set up async callback functions
+            if parent_method._dbus_async_callbacks:
+                (return_callback, error_callback) = parent_method._dbus_async_callbacks
+                keywords[return_callback] = lambda *retval: dbus.service._method_reply_return(connection, message, method_name, signature, *retval)
+                keywords[error_callback] = lambda exception: dbus.service._method_reply_error(connection, message, exception)
+
+            # include the sender if desired
+            if parent_method._dbus_sender_keyword:
+                keywords[parent_method._dbus_sender_keyword] = message.get_sender()
+
+            if parent_method._dbus_message_keyword:
+                keywords[parent_method._dbus_message_keyword] = message
+
+            # call method
+            retval = candidate_method(self, *args, **keywords)
+
+            # we're done - the method has got callback functions to reply with
+            if parent_method._dbus_async_callbacks:
+                return
+
+            # otherwise we send the return values in a reply. if we have a
+            # signature, use it to turn the return value into a tuple as
+            # appropriate
+            if parent_method._dbus_out_signature:
+                # if we have zero or one return values we want make a tuple
+                # for the _method_reply_return function, otherwise we need
+                # to check we're passing it a sequence
+                if len(signature) == 0:
+                    if retval == None:
+                        retval = ()
+                    else:
+                        raise TypeError('%s has an empty output signature but did not return None' %
+                            method_name)
+                elif len(signature) == 1:
+                    retval = (retval,)
+                else:
+                    if operator.isSequenceType(retval):
+                        # multi-value signature, multi-value return... proceed unchanged
+                        pass
+                    else:
+                        raise TypeError('%s has multiple output values in signature %s but did not return a sequence' %
+                            (method_name, signature))
+
+            # no signature, so just turn the return into a tuple and send it as normal
+            else:
+                signature = None
+                if retval == None:
+                    retval = ()
+                else:
+                    retval = (retval,)
+
+            dbus.service._method_reply_return(connection, message, method_name, signature, *retval)
+        except Exception, exception:
+            # send error reply
+            dbus.service._method_reply_error(connection, message, exception)
+
+    @method('org.freedesktop.DBus.Introspectable', in_signature='', out_signature='s', dbus_message_keyword="dbus_message")
+    def Introspect(self, dbus_message=None):
+        reflection_data = '<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN" "http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">\n'
+        op = dbus_message.get_path()
+        reflection_data += '<node name="%s">\n' % (op)
+
+        interfaces = self._dbus_class_table[self.__class__.__module__ + '.' + self.__class__.__name__]
+        for (name, funcs) in interfaces.iteritems():
+            reflection_data += '  <interface name="%s">\n' % (name)
+
+            for func in funcs.values():
+                if getattr(func, '_dbus_is_method', False):
+                    reflection_data += self.__class__._reflect_on_method(func)
+                elif getattr(func, '_dbus_is_signal', False):
+                    reflection_data += self.__class__._reflect_on_signal(func)
+
+            reflection_data += '  </interface>\n'
+
+        reflection_data += '</node>\n'
+
+        return reflection_data
+
+    def __repr__(self):
+        return '<dbus_helpers.FallbackObject %s on %r at %#x>' % (self._fallback_object_path, self._name, id(self))
+    __str__ = __repr__
+
diff --git a/services/datastore/sugar-data-store b/services/datastore/sugar-data-store
new file mode 100644
index 0000000..7940c74
--- /dev/null
+++ b/services/datastore/sugar-data-store
@@ -0,0 +1,32 @@
+#!/usr/bin/python
+# vi: ts=4 ai noet 
+#
+# Copyright (C) 2006, Red Hat, Inc.
+#
+# 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 St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import sys
+import logging
+
+from sugar import logger
+from sugar import env
+
+sys.path.insert(0, env.get_services_dir())
+
+logger.start('data-store')
+logging.info('Starting the data store...')
+
+from datastore import datastore
+datastore.main()