0dc2f1da8dbb26951752e65b050b8598b9e9080c
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 1.10 2001-10-09 23:58:10 richard Exp $
20 import anydbm, os, marshal
21 from roundup import hyperdb, date, password
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 = {}
44 self.transactions = []
46 #
47 # Classes
48 #
49 def __getattr__(self, classname):
50 """A convenient way of calling self.getclass(classname)."""
51 return self.classes[classname]
53 def addclass(self, cl):
54 cn = cl.classname
55 if self.classes.has_key(cn):
56 raise ValueError, cn
57 self.classes[cn] = cl
59 def getclasses(self):
60 """Return a list of the names of all existing classes."""
61 l = self.classes.keys()
62 l.sort()
63 return l
65 def getclass(self, classname):
66 """Get the Class object representing a particular class.
68 If 'classname' is not a valid class name, a KeyError is raised.
69 """
70 return self.classes[classname]
72 #
73 # Class DBs
74 #
75 def clear(self):
76 for cn in self.classes.keys():
77 db = os.path.join(self.dir, 'nodes.%s'%cn)
78 anydbm.open(db, 'n')
79 db = os.path.join(self.dir, 'journals.%s'%cn)
80 anydbm.open(db, 'n')
82 def getclassdb(self, classname, mode='r'):
83 ''' grab a connection to the class db that will be used for
84 multiple actions
85 '''
86 path = os.path.join(os.getcwd(), self.dir, 'nodes.%s'%classname)
87 if os.path.exists(path):
88 return anydbm.open(path, mode)
89 else:
90 return anydbm.open(path, 'n')
92 #
93 # Nodes
94 #
95 def addnode(self, classname, nodeid, node):
96 ''' add the specified node to its class's db
97 '''
98 db = self.getclassdb(classname, 'c')
99 # now save the marshalled data
100 db[nodeid] = marshal.dumps(node)
101 db.close()
102 setnode = addnode
104 def getnode(self, classname, nodeid, cldb=None):
105 ''' add the specified node to its class's db
106 '''
107 db = cldb or self.getclassdb(classname)
108 if not db.has_key(nodeid):
109 raise IndexError, nodeid
110 res = marshal.loads(db[nodeid])
111 if not cldb: db.close()
112 return res
114 def hasnode(self, classname, nodeid, cldb=None):
115 ''' add the specified node to its class's db
116 '''
117 db = cldb or self.getclassdb(classname)
118 res = db.has_key(nodeid)
119 if not cldb: db.close()
120 return res
122 def countnodes(self, classname, cldb=None):
123 db = cldb or self.getclassdb(classname)
124 return len(db.keys())
125 if not cldb: db.close()
126 return res
128 def getnodeids(self, classname, cldb=None):
129 db = cldb or self.getclassdb(classname)
130 res = db.keys()
131 if not cldb: db.close()
132 return res
134 #
135 # Journal
136 #
137 def addjournal(self, classname, nodeid, action, params):
138 ''' Journal the Action
139 'action' may be:
141 'create' or 'set' -- 'params' is a dictionary of property values
142 'link' or 'unlink' -- 'params' is (classname, nodeid, propname)
143 'retire' -- 'params' is None
144 '''
145 entry = (nodeid, date.Date().get_tuple(), self.journaltag, action,
146 params)
147 db = anydbm.open(os.path.join(self.dir, 'journals.%s'%classname), 'c')
148 if db.has_key(nodeid):
149 s = db[nodeid]
150 l = marshal.loads(db[nodeid])
151 l.append(entry)
152 else:
153 l = [entry]
154 db[nodeid] = marshal.dumps(l)
155 db.close()
157 def getjournal(self, classname, nodeid):
158 ''' get the journal for id
159 '''
160 # attempt to open the journal - in some rare cases, the journal may
161 # not exist
162 try:
163 db = anydbm.open(os.path.join(self.dir, 'journals.%s'%classname),
164 'r')
165 except anydbm.open, error:
166 if error.args[0] != 2: raise
167 return []
168 journal = marshal.loads(db[nodeid])
169 res = []
170 for entry in journal:
171 (nodeid, date_stamp, self.journaltag, action, params) = entry
172 date_obj = date.Date(date_stamp)
173 res.append((nodeid, date_obj, self.journaltag, action, params))
174 db.close()
175 return res
177 def close(self):
178 ''' Close the Database - we must release the circular refs so that
179 we can be del'ed and the underlying anydbm connections closed
180 cleanly.
181 '''
182 self.classes = None
185 #
186 # Basic transaction support
187 #
188 def commit(self):
189 ''' Commit the current transactions.
190 '''
191 # lock the DB
192 for action, classname, entry in self.transactions:
193 # write the node, figure what's changed for the journal.
194 pass
195 # unlock the DB
197 def rollback(self):
198 ''' Reverse all actions from the current transaction.
199 '''
200 self.transactions = []
202 #
203 #$Log: not supported by cvs2svn $
204 #Revision 1.9 2001/10/09 07:25:59 richard
205 #Added the Password property type. See "pydoc roundup.password" for
206 #implementation details. Have updated some of the documentation too.
207 #
208 #Revision 1.8 2001/09/29 13:27:00 richard
209 #CGI interfaces now spit up a top-level index of all the instances they can
210 #serve.
211 #
212 #Revision 1.7 2001/08/12 06:32:36 richard
213 #using isinstance(blah, Foo) now instead of isFooType
214 #
215 #Revision 1.6 2001/08/07 00:24:42 richard
216 #stupid typo
217 #
218 #Revision 1.5 2001/08/07 00:15:51 richard
219 #Added the copyright/license notice to (nearly) all files at request of
220 #Bizar Software.
221 #
222 #Revision 1.4 2001/07/30 01:41:36 richard
223 #Makes schema changes mucho easier.
224 #
225 #Revision 1.3 2001/07/25 01:23:07 richard
226 #Added the Roundup spec to the new documentation directory.
227 #
228 #Revision 1.2 2001/07/23 08:20:44 richard
229 #Moved over to using marshal in the bsddb and anydbm backends.
230 #roundup-admin now has a "freshen" command that'll load/save all nodes (not
231 # retired - mod hyperdb.Class.list() so it lists retired nodes)
232 #
233 #