How should I use replication with databases behind reverse proxy

[kishieel]

I have two CouchDB instances behind reverse proxies. They can be accessed with following urls.

DB1: https://example-1.com/_db
DB2: https://example-2.com/_db

Notice: _db is not the name of database, but it is the root path for CouchDB instance, so when I call https://example-1.com/_db I am getting:

{"couchdb":"Welcome","version":"3.3.3", ...}

Now I am trying to replicate data from DB1 to DB2. I created following document in DB1:

{
    "_id": "replication_test",
    "source_proxy": "https://username:[email protected]/_db",
    "target_proxy": "https://username:[email protected]/_db",
    "source": "https://username:[email protected]/_db/test-database",
    "target": "https://username:[email protected]/_db/test-database",
    "create_target": true
}

But it always ends with an error:

[error] 2024-07-16T14:43:18.491719Z [email protected] <0.14885.0> -------- error:function_clause: Replication 3770eba19a8e88abe8ad9ba323b2833a failed to start "https://example-1.com/_db/test-database/" -> "https://example-1.com/_db/test-database/" doc null:null stack:[{couch_replicator_auth_session,http_response,[connection_closed_no_retry,{state,0,undefined,"username","password",30000,<0.14909.0>,[{is_ssl,true},{proxy_host,"domain-1.com"},{proxy_password,"password"},{proxy_port,443},{proxy_user,"username"},{socket_options,[{keepalive,true},{nodelay,false}]},{ssl_options,[{depth,3},{verify,verify_none}]}],"https://domain-1.com/_session",infinity,0,false}],[{file,"src/couch_replicator_auth_session.erl"},{line,371}]},{couch_replicator_auth_session,init_state,1,[{file,"src/couch_replicator_auth_session.erl"},{line,188}]}]

Assuming from error log CouchDB is sending request to https://domain-1.com/_session which cannot work as this endpoint does not exist in this setup. It should be https://domain-1.com/_db/_session.

I tried also without source_proxy and target_proxy but in this case I am getting

{"error":"replication_auth_error","reason":"{session_request_forbidden,\"https://domain-1.com/_session\",\n                           \"username\"}"}

Which also shows that the request is not being sent to correct destination.

Am I using proxy options wrong? Or replication in CouchDB is not able to work when the database is not exposed from the root path?

[rnewson]

CouchDB is not relocatable in that way, you'll need to configure your proxy to rewrite the paths to match the couchdb api (/$dbname, etc).