fix: restoring saved flags error and resuming wandb session in test mode disabled

[alexmelekhin]

• "following arguments are required" error: Running testing script as described in README.md now returns following error:

  $ python main.py --mode test --seqL 5 --pooling --dataset oxford-v1.0 --split test --resume ./data/runs/Mar28_12-31-26_l5_ox10_MoP_negMoP
  Restored flags: ['--optim', 'SGD', '--lr', '0.001', '--lrStep', '5', '--lrGamma', '0.5', '--weightDecay', '0.001', '--momentum', '0.9', '--seed', '123', '--patience', '0', '--runsPath', './data/runs', '--savePath', 'checkpoints', '--outDims', '4096', '--margin', '0.1']
  usage: main.py [-h] --mode {train,test} [--batchSize BATCHSIZE] [--cacheBatchSize CACHEBATCHSIZE] [--cacheRefreshRate CACHEREFRESHRATE] [--nEpochs NEPOCHS] [--start-epoch N]
               [--nGPU NGPU] [--optim {SGD,ADAM}] [--lr LR] [--lrStep LRSTEP] [--lrGamma LRGAMMA] [--weightDecay WEIGHTDECAY] [--momentum MOMENTUM] [--nocuda] [--threads THREADS]
               [--seed SEED] [--patience PATIENCE] [--evalEvery EVALEVERY] [--expName EXPNAME] [--runsPath RUNSPATH] [--savePath SAVEPATH] [--cachePath CACHEPATH]
               [--resultsPath RESULTSPATH] [--resume RESUME] [--ckpt {latest,best}] [--split {test,train,val}] [--numSamples2Project NUMSAMPLES2PROJECT] [--extractOnly]
               [--predictionsFile PREDICTIONSFILE] [--seqL_filterData SEQL_FILTERDATA] --dataset {nordland-sw,nordland-sf,oxford-v1.0,oxford-pnv} [--pooling] --seqL SEQL
               [--outDims OUTDIMS] [--margin MARGIN] [--descType DESCTYPE] [--matcher {seqMatchNet,None}] [--loss_trip_method {centerOnly,meanOfPairs}]
               [--neg_trip_method {centerOnly,meanOfPairs}]
  main.py: error: the following arguments are required: --mode, --dataset, --seqL

  This is because of restoring flags from flags.json when opt.resume == True deletes all previously passed arguments. While I did not tried to fix restoring arguments in training mode, this PR simply fixes this error in test mode by disabling restoring flags if opt.mode == 'test'.

• wandb resuming in test mode error: Starting test script now results in incorrect attempt to resume non-existing wandb session. This PR fixes that issue if opt.mode == 'test'

[oravus]

Hi @metra4ok, thanks for the PR. I found the root cause of this, which is now fixed through this commit. Your solution would have worked too but args such as outdims better be restored through the model when testing.

[oravus]

Have included your suggestion for wandb resume anyway, thanks again @metra4ok.