I'm building a chat system based on ejabberd using an iOS client (and XMPPFramework).
My current chat system supports only one-on-one conversations between users saving a chat history on a MySQL database.
In order to recreate the same chat system, i'd need ejabberd to retrieve chat history from my database so the users don't lose previous conversations when switching to the new chat system.
I'd like not to save the conversation client-side since the iOS app can be deleted and reinstalled (or the user could switch device).
Is it possible to make ejabberd read chat history from my MySQL db?
This should be possible with mod_archive_odbc. It's an additional ejabberd module that you can find by checking out http://svn.process-one.net/ejabberd-modules/ with SVN. An example on how to build and install a module on Debian can be found here.
The question is a bit old, but if anyone is still interested.
This could be achieved by Message Archive Management (http://xmpp.org/extensions/xep-0313.html).
Most complete implementation of this XEP is in MongooseIM (fork of ejabberd). https://github.com/esl/MongooseIM/blob/master/apps/ejabberd/src/mod_mam.erl
ProcessOne page claims to have support for archiving on this page: http://www.process-one.net/en/ejabberd/#getejabberd, but there is no mention on this page: http://www.process-one.net/en/ejabberd/protocols/. Looks like they are using their custom specification.
Please note, that you won't be able to use mod_mam from MongooseIM directly with processone ejabberd, because of small differences in function arguments that module is calling.
来源：https://stackoverflow.com/questions/9911210/ejabberd-retrieve-chat-history-from-mysql-db