On Nov 18, 2009, at 6:51 PM, Matt Goodall wrote: > 2009/11/18 Sebastian Cohnen <[email protected]>: >> afaik, this behavior is normal. you just created another (and new) >> resource/document. >> >> have a look (the database test is new and never contained docs with id 'foo' >> or 'foobar'): >> >> $ curl -X PUT -d '{"_id": "foo", "_rev": >> "1-967a00dff5e02add41819138abb3284d", "num": 1}' >> "http://localhost:5984/test/foo"; >> {"ok":true,"id":"foo","rev":"2-65371ad05fc99a9b794f68c6003bc8da"} >> >> $ curl -X PUT -d '{"_id": "foobar", "_rev": "4-anythingyouwant", "num": 1}' >> "http://localhost:5984/test/foobar"; >> {"ok":true,"id":"foobar","rev":"5-084106c9189a346875996e76c1833630"} > > Hmm, seems wrong to me although I can imagine that's useful during > replication (which doesn't mean it should work for a PUT). However, > why does the following fail then: > > $ curl -X "PUT" -d '{}' "http://localhost:15984/test/foo"; > {"ok":true,"id":"foo","rev":"1-967a00dff5e02add41819138abb3284d"} > $ curl -X "PUT" -d '{"_id": "foo", "_rev": > "1-967a00dff5e02add41819138abb3284d"}' > "http://localhost:15984/test/foo"; > {"ok":true,"id":"foo","rev":"2-7051cbe5c8faecd085a3fa619e6e6337"} > $ curl -X "DELETE" > "http://localhost:15984/test/foo?rev=2-7051cbe5c8faecd085a3fa619e6e6337"; > {"ok":true,"id":"foo","rev":"3-7379b9e515b161226c6559d90c4dc49f"} > $ curl -X "PUT" -d '{"_id": "foo", "_rev": > "1-967a00dff5e02add41819138abb3284d"}' > "http://localhost:15984/test/foo"; > {"error":"conflict","reason":"Document update conflict."} > > - Matt > >> >> >> cheers, >> >> tisba / Sebastian >> >> On 18.11.2009, at 23:56, Matt Goodall wrote: >> >>> Hi, >>> >>> I swear I've reported this odd behaviour before but I can't find any >>> mention of it now ... >>> >>> I have some code with a race condition that is caused by what I >>> believe is a bug in CouchDB - a deleted document can be updated using >>> an old, valid rev. >>> >>> If a document has not been deleted then CouchDB correctly returns a >>> conflict error if the latest rev is not sent. However, once deleted, >>> any rev in the docs history can be sent as the update and, as long as >>> the doc is changed in some way, the document will be resurrected with >>> a rev whose sequence is 1 more than that sent in the update. >>> >>> Create new doc ... >>> $ curl -X "PUT" -d '{"_id": "foo"}' http://localhost:15984/test/foo >>> {"ok":true,"id":"foo","rev":"1-967a00dff5e02add41819138abb3284d"} >>> >>> Update a couple of times to move the rev on ... >>> $ curl -X "PUT" -d '{"_id": "foo", "_rev": >>> "1-967a00dff5e02add41819138abb3284d"}' http://localhost:15984/test/foo >>> {"ok":true,"id":"foo","rev":"2-7051cbe5c8faecd085a3fa619e6e6337"} >>> $ curl -X "PUT" -d '{"_id": "foo", "_rev": >>> "2-7051cbe5c8faecd085a3fa619e6e6337"}' http://localhost:15984/test/foo >>> {"ok":true,"id":"foo","rev":"3-825cb35de44c433bfb2df415563a19de"} >>> >>> Delete the doc ... >>> $ curl -X "DELETE" >>> "http://localhost:15984/test/foo?rev=3-825cb35de44c433bfb2df415563a19de"{"ok":true,"id":"foo","rev":"4-1df13287548620bf858cf9d1b810972a"} >>> >>> Update using an old rev, changing something ... >>> $ curl -X "PUT" -d '{"_id": "foo", "_rev": >>> "1-967a00dff5e02add41819138abb3284d", "num": 1}' >>> http://localhost:15984/test/foo >>> {"ok":true,"id":"foo","rev":"2-65371ad05fc99a9b794f68c6003bc8da"} >>> >>> Now, I can sort of understand how something like that might happen >>> during replication but there's no replication going on here and >>> there's no conflict created in the database. >>> >>> I can't think of a way around the problem at the moment, other than >>> marking the document for deletion and then sweeping it later when >>> something else is hopefully not going to be touching the document. >>> But, frankly, that's horrible, >>> >>> - Matt
Hi Matt, bizarre. Your latest email shows the behavior I expect -- you tried to PUT a document using an incorrect MVCC revision, and you got a conflict as a result. A successful PUT of a new document with an _id that corresponds to a previously deleted document should omit the MVCC rev. Your first email is the weird one -- you supplied an old MVCC _rev, but changed the body to something different than the body at the time the doc was deleted, and it worked. I can confirm this. Can you file a JIRA ticket? Best, Adam
