couchdb-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Adam Kocoloski <>
Subject Re: documentation of replication protocol?
Date Wed, 21 Apr 2010 13:49:43 GMT

On Apr 21, 2010, at 8:33 AM, Miles Fidelman wrote:

> J Chris Anderson wrote:
>> On Apr 20, 2010, at 7:29 PM, Miles Fidelman wrote:
>>> I've been looking, but can't seem to find any good documentation of the inter-node
protocol used for replication.
>> As far as I know, the best source for documentation is the code, right now.
> <snip>
>> This is the hard coding (in Ruby) I had to add, to used the CouchDB replicator to
pull from the Booth server:
> aaarrrgggh......
> I don't suppose anyone out there has scribbled down anything resembling a sequence diagram
or flowchart or list of bullet points or something that summarizes the steps that happen,
and the code that gets run when POST /_replicate is invoked, or an ASN.1-like summary of the
messages that get exchanged between two couch instances during replication

Miles, at a high level it looks like this:

There are some added details regarding efficient replication of document attachments, and
of course that slide doesn't describe the request and response formats for those 4 resources.
 But that's the sequence of steps that the replicator loops through.


> right now, replication reminds me of the old Sidney Harris Cartoon, "then a miracle occurs"
> -- 
> In theory, there is no difference between theory and practice.
> In<fnord>  practice, there is.   .... Yogi Berra

View raw message