36fb3df7c33e6e11394c09d5c6bd75464c482563
1 #
2 # Copyright (c) 2001 Bizar Software Pty Ltd (http://www.bizarsoftware.com.au/)
3 # This module is free software, and you may redistribute it and/or modify
4 # under the same terms as Python, so long as this copyright message and
5 # disclaimer are retained in their original form.
6 #
7 # IN NO EVENT SHALL BIZAR SOFTWARE PTY LTD BE LIABLE TO ANY PARTY FOR
8 # DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
9 # OUT OF THE USE OF THIS CODE, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE
10 # POSSIBILITY OF SUCH DAMAGE.
11 #
12 # BIZAR SOFTWARE PTY LTD SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
13 # BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
14 # FOR A PARTICULAR PURPOSE. THE CODE PROVIDED HEREUNDER IS ON AN "AS IS"
15 # BASIS, AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
16 # SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
17 #
18 #$Id: back_anydbm.py,v 1.7 2001-08-12 06:32:36 richard Exp $
20 import anydbm, os, marshal
21 from roundup import hyperdb, date
23 #
24 # Now the database
25 #
26 class Database(hyperdb.Database):
27 """A database for storing records containing flexible data types."""
29 def __init__(self, storagelocator, journaltag=None):
30 """Open a hyperdatabase given a specifier to some storage.
32 The meaning of 'storagelocator' depends on the particular
33 implementation of the hyperdatabase. It could be a file name,
34 a directory path, a socket descriptor for a connection to a
35 database over the network, etc.
37 The 'journaltag' is a token that will be attached to the journal
38 entries for any edits done on the database. If 'journaltag' is
39 None, the database is opened in read-only mode: the Class.create(),
40 Class.set(), and Class.retire() methods are disabled.
41 """
42 self.dir, self.journaltag = storagelocator, journaltag
43 self.classes = {}
45 #
46 # Classes
47 #
48 def __getattr__(self, classname):
49 """A convenient way of calling self.getclass(classname)."""
50 return self.classes[classname]
52 def addclass(self, cl):
53 cn = cl.classname
54 if self.classes.has_key(cn):
55 raise ValueError, cn
56 self.classes[cn] = cl
58 def getclasses(self):
59 """Return a list of the names of all existing classes."""
60 l = self.classes.keys()
61 l.sort()
62 return l
64 def getclass(self, classname):
65 """Get the Class object representing a particular class.
67 If 'classname' is not a valid class name, a KeyError is raised.
68 """
69 return self.classes[classname]
71 #
72 # Class DBs
73 #
74 def clear(self):
75 for cn in self.classes.keys():
76 db = os.path.join(self.dir, 'nodes.%s'%cn)
77 anydbm.open(db, 'n')
78 db = os.path.join(self.dir, 'journals.%s'%cn)
79 anydbm.open(db, 'n')
81 def getclassdb(self, classname, mode='r'):
82 ''' grab a connection to the class db that will be used for
83 multiple actions
84 '''
85 path = os.path.join(os.getcwd(), self.dir, 'nodes.%s'%classname)
86 if os.path.exists(path):
87 return anydbm.open(path, mode)
88 else:
89 return anydbm.open(path, 'n')
91 #
92 # Nodes
93 #
94 def addnode(self, classname, nodeid, node):
95 ''' add the specified node to its class's db
96 '''
97 db = self.getclassdb(classname, 'c')
99 # convert the instance data to builtin types
100 properties = self.classes[classname].properties
101 for key in properties.keys():
102 if isinstance(properties[key], hyperdb.Date):
103 node[key] = node[key].get_tuple()
104 elif isinstance(properties[key], hyperdb.Interval):
105 node[key] = node[key].get_tuple()
107 # now save the marshalled data
108 db[nodeid] = marshal.dumps(node)
109 db.close()
110 setnode = addnode
112 def getnode(self, classname, nodeid, cldb=None):
113 ''' add the specified node to its class's db
114 '''
115 db = cldb or self.getclassdb(classname)
116 if not db.has_key(nodeid):
117 raise IndexError, nodeid
118 res = marshal.loads(db[nodeid])
120 # convert the marshalled data to instances
121 properties = self.classes[classname].properties
122 for key in properties.keys():
123 if key == self.RETIRED_FLAG: continue
124 if isinstance(properties[key], hyperdb.Date):
125 res[key] = date.Date(res[key])
126 elif isinstance(properties[key], hyperdb.Interval):
127 res[key] = date.Interval(res[key])
129 if not cldb: db.close()
130 return res
132 def hasnode(self, classname, nodeid, cldb=None):
133 ''' add the specified node to its class's db
134 '''
135 db = cldb or self.getclassdb(classname)
136 res = db.has_key(nodeid)
137 if not cldb: db.close()
138 return res
140 def countnodes(self, classname, cldb=None):
141 db = cldb or self.getclassdb(classname)
142 return len(db.keys())
143 if not cldb: db.close()
144 return res
146 def getnodeids(self, classname, cldb=None):
147 db = cldb or self.getclassdb(classname)
148 res = db.keys()
149 if not cldb: db.close()
150 return res
152 #
153 # Journal
154 #
155 def addjournal(self, classname, nodeid, action, params):
156 ''' Journal the Action
157 'action' may be:
159 'create' or 'set' -- 'params' is a dictionary of property values
160 'link' or 'unlink' -- 'params' is (classname, nodeid, propname)
161 'retire' -- 'params' is None
162 '''
163 entry = (nodeid, date.Date().get_tuple(), self.journaltag, action,
164 params)
165 db = anydbm.open(os.path.join(self.dir, 'journals.%s'%classname), 'c')
166 if db.has_key(nodeid):
167 s = db[nodeid]
168 l = marshal.loads(db[nodeid])
169 l.append(entry)
170 else:
171 l = [entry]
172 db[nodeid] = marshal.dumps(l)
173 db.close()
175 def getjournal(self, classname, nodeid):
176 ''' get the journal for id
177 '''
178 # attempt to open the journal - in some rare cases, the journal may
179 # not exist
180 try:
181 db = anydbm.open(os.path.join(self.dir, 'journals.%s'%classname),
182 'r')
183 except anydbm.open, error:
184 if error.args[0] != 2: raise
185 return []
186 journal = marshal.loads(db[nodeid])
187 res = []
188 for entry in journal:
189 (nodeid, date_stamp, self.journaltag, action, params) = entry
190 date_obj = date.Date(date_stamp)
191 res.append((nodeid, date_obj, self.journaltag, action, params))
192 db.close()
193 return res
195 def close(self):
196 ''' Close the Database - we must release the circular refs so that
197 we can be del'ed and the underlying anydbm connections closed
198 cleanly.
199 '''
200 self.classes = None
203 #
204 # Basic transaction support
205 #
206 # TODO: well, write these methods (and then use them in other code)
207 def register_action(self):
208 ''' Register an action to the transaction undo log
209 '''
211 def commit(self):
212 ''' Commit the current transaction, start a new one
213 '''
215 def rollback(self):
216 ''' Reverse all actions from the current transaction
217 '''
219 #
220 #$Log: not supported by cvs2svn $
221 #Revision 1.6 2001/08/07 00:24:42 richard
222 #stupid typo
223 #
224 #Revision 1.5 2001/08/07 00:15:51 richard
225 #Added the copyright/license notice to (nearly) all files at request of
226 #Bizar Software.
227 #
228 #Revision 1.4 2001/07/30 01:41:36 richard
229 #Makes schema changes mucho easier.
230 #
231 #Revision 1.3 2001/07/25 01:23:07 richard
232 #Added the Roundup spec to the new documentation directory.
233 #
234 #Revision 1.2 2001/07/23 08:20:44 richard
235 #Moved over to using marshal in the bsddb and anydbm backends.
236 #roundup-admin now has a "freshen" command that'll load/save all nodes (not
237 # retired - mod hyperdb.Class.list() so it lists retired nodes)
238 #
239 #