Error log is not informative enough to identify the problem when trying to connect to Transmission

[dmak]

I have started flood as follows:

/usr/bin/flood --port=3001 --rundir=${FLOOD_HOME}/.flood

When opening /overview page it offers me to specify the client and credentials to connect to. Unfortunately I get "Connection could not be verified":

Log entry:

Jun 27 22:46:16 linux flood[3508121]: GET /api/activity-stream 200 2.131 ms - -                                                         
Jun 27 22:47:09 linux flood[3508121]: Error                                                                                             
Jun 27 22:47:09 linux flood[3508121]:     at ClientRequestManager4.updateSessionID (/snapshot/tmp/bazel-source-roots/0/dist/index.js)   
Jun 27 22:47:09 linux flood[3508121]:     at process.processTicksAndRejections (node:internal/process/task_queues:95:5)                 
Jun 27 22:47:14 linux flood[3508121]: PATCH /api/auth/users/admin 200 39.572 ms - 2                                                    
Jun 27 22:47:30 linux flood[3508121]: GET /api/client/connection-test 500 5.703 ms - 21                                                 

flood v4.8.2-0 installed from provided .deb package. Transmission v4.0.6. The credentials have been tested and work well with transmission-remote (I am able to add and start torrents from CLI), so transmission RPC is working OK:

# netstat -an | grep 9091
tcp     0    0 0.0.0.0:9091      0.0.0.0:*       LISTEN    3466510/transmission-deamon

I have also tried to start Flood as below:

/usr/bin/flood --port=3001 --rundir="${FLOOD_HOME}/.flood" --noauth --trurl="http://localhost:9091/transmission/rpc" --truser="test" --trpass="*[hidden]*"

without success.

tcpdump output brings me to the idea that maybe there is some protocol miscommunication (because Sync is followed by Reset) 🤔

# tcpdump 'tcp and (dst port 9091 or src port 9091)' -i lo

18:20:19.628289 IP6 localhost.44420 > localhost.transmission: Flags [S], seq 4294935861, win 65476, options [mss 65476,sackOK,TS val 2222396008 ecr 0,nop,wscale 7], length 0                                                                                                           
18:20:19.628309 IP6 localhost.transmission > localhost.44420: Flags [R.], seq 0, ack 4294935862, win 0, length 0                            
18:20:19.632984 IP6 localhost.44436 > localhost.transmission: Flags [S], seq 3473539940, win 65476, options [mss 65476,sackOK,TS val 2222396013 ecr 0,nop,wscale 7], length 0
18:20:19.632996 IP6 localhost.transmission > localhost.44436: Flags [R.], seq 0, ack 3473539941, win 0, length 0
18:20:19.633116 IP6 localhost.44448 > localhost.transmission: Flags [S], seq 88530744, win 65476, options [mss 65476,sackOK,TS val 2222396013 ecr 0,nop,wscale 7], length 0
18:20:19.633124 IP6 localhost.transmission > localhost.44448: Flags [R.], seq 0, ack 88530745, win 0, length 0

Similar issues: #624, #102.

Expected

• Next to HTTP 500 log message report what exactly went wrong ("Connection refused", "Authentication failed", ...).
• Add possibility to increase log level to get more insight about what Transmission URL was called and what was the request/response/HTTP status code.