Make the docker container work with an existing couchDB

[Louis-T]

Description

Hi

In the process of starting a new swarmpit instance, it will try to create the _users, _replicator and _global_changes databases on the specified couchDB.
In the event of any of those already present in the couchDB, it will fail and crash.

Could you make a "check" before creating the db ? In case they are already present ? Thanks !

Steps to reproduce the issue:

1. Create a couchDB instance
2. Create one of _users, _replicator or _global_changes on it
3. Launch swarmpit

What happens:

21-01-07 10:12:01 node1-monitor_swarmpit-ui-1 ERROR [swarmpit.http:71] - Request execution failed! Scope: DB
|> PUT http://xxxx:xxxx@couchdb:5984/_replicator
|> Headers: null
|> Payload: null
|< Message: clj-http: status 412
|< Data: {
  "headers" : {
    "Cache-Control" : "must-revalidate",
    "Connection" : "close",
    "Content-Length" : "95",
    "Content-Type" : "application/json",
    "Date" : "Thu, 07 Jan 2021 10:12:01 GMT",
    "Server" : "CouchDB/3.1.0 (Erlang OTP/20)",
    "X-Couch-Request-ID" : "67a1bcf71d",
    "X-CouchDB-Body-Time" : "0"
  },
  "status" : 412,
  "body" : "{\"error\":\"file_exists\",\"reason\":\"The database could not be created, the file already exists.\"}\n",
  "reason-phrase" : "Precondition Failed",
  "type" : "clj-http.client/unexceptional-status"
}
Exception in thread "main" clojure.lang.ExceptionInfo: DB error: file_exists {:status 412, :type :http-client, :headers {"Cache-Control" "must-revalidate", "Connection" "close", "Content-Length" "95", "Content-Type" "application/json", "Date" "Thu, 07 Jan 2021 10:12:01 GMT", "Server" "CouchDB/3.1.0 (Erlang OTP/20)", "X-Couch-Request-ID" "67a1bcf71d", "X-CouchDB-Body-Time" "0"}, :body {:error "file_exists"}}
	at swarmpit.http$execute_in_scope.invokeStatic(http.clj:112)
	at swarmpit.http$execute_in_scope.invoke(http.clj:80)
	at swarmpit.couchdb.client$execute.invokeStatic(client.clj:10)
	at swarmpit.couchdb.client$execute.invoke(client.clj:7)
	at swarmpit.couchdb.client$create_sns_replicator.invokeStatic(client.clj:107)
	at swarmpit.couchdb.client$create_sns_replicator.invoke(client.clj:105)
	at swarmpit.couchdb.migration$single_node_setup.invokeStatic(migration.clj:19)
	at swarmpit.couchdb.migration$single_node_setup.invoke(migration.clj:16)
	at swarmpit.couchdb.migration$migrate.invokeStatic(migration.clj:40)
	at swarmpit.couchdb.migration$migrate.invoke(migration.clj:36)
	at swarmpit.database$init_couch.invokeStatic(database.clj:67)
	at swarmpit.database$init_couch.invoke(database.clj:59)
	at swarmpit.database$init.invokeStatic(database.clj:81)
	at swarmpit.database$init.invoke(database.clj:79)
	at swarmpit.server$_main.invokeStatic(server.clj:92)
	at swarmpit.server$_main.doInvoke(server.clj:90)
	at clojure.lang.RestFn.invoke(RestFn.java:397)
	at clojure.lang.AFn.applyToHelper(AFn.java:152)
	at clojure.lang.RestFn.applyTo(RestFn.java:132)
	at swarmpit.server.main(Unknown Source)

For the record, I had the same problem with the _users db just before this, so I deleted it, but I can't delete _replicator !

Additional information (e.g. docker version, cluster setup,...):

• Latest version of swarmpit
• Docker version 19.03.5, build 633a0ea838
• Trying to deploy it in a swarm
• The couchDB is an existing cluster

[nohaapav]

migration is done only once and changelog written in couch .. this is most probably related to different problem ..

[nohaapav]

Oh i see, you already have your own couch DB instance .. in that case you have to create migration document so swarmpit app knows the data model is already there.

[nohaapav]

https://github.com/swarmpit/swarmpit/blob/master/src/clj/swarmpit/couchdb/migration.clj#L32
https://github.com/swarmpit/swarmpit/blob/master/src/clj/swarmpit/couchdb/client.clj#L126

Document for single-node-setup migration must be created before swarmpit start

[Louis-T]

Hi !
Thanks for the pointers 😃

By creating the following file in my couchDB (database: swarmpit), I was indeed able to start the swarmpit app !

{
  "_id": "1c516abfac159b53e5b9edd5d900492b",
  "_rev": "1-c8219b09423abbe3f9f08d5cad2ca9a0",
  "type": "migration",
  "name": "single-node-setup",
  "result": null
}

Thanks again, I'm closing the issue.

[dazinator]

@Louis-T I am hitting a similar issue in #670 - any pointers would be greatly appreciated!