Errcheck phase 1 (#1715)

* Avoid redundant logging in migrations

Return the error and let the caller handle the logging of the error if
needed.

While here, defer m.Close() to the function boundary.

* Treat errors as values

Use %v rather than %s and pass the errors directly.

* Generate a wrapped error on stat-failure

* Log 3 unchecked errors

Rather than ignore errors, log them at
the WARNING log level.

The server has been functioning without these, so assume they are not at
the ERROR level.

* Propagate errors upward

Failure in path generation was ignored. Propagate the errors upward the
call stack, so it can be handled at the level of orchestration.

* Warn on errors

Log errors rather than quenching them.

Errors are logged at the Warn-level for now.

* Check error when creating test databases

Use the builtin log package and stop the program fatally on error.

* Add warnings to uncheck task errors

Focus on the task system in a single commit, logging unchecked
errors as warnings.

* Warn-on-error in API routes

Look through the API routes, and make sure errors are being logged if
they occur. Prefer the Warn-log-level because none of these has proven
to be fatal in the system up until now.

* Propagate error when adding Util API

* Propagate error on adding util API

* Return unhandled error

* JS log API: propagate and log errors

* JS Plugins: log GQL addition failures.

* Warn on failure to write to stdin

* Warn on failure to stop task

* Wrap viper.BindEnv

The current viper code only errors if no name is provided, so it should
never fail. Rewrite the code flow to factor through a panic-function.

This removes error warnings from this part of the code.

* Log errors in concurrency test

If we can't initialize the configuration, treat the test as a failure.

* Warn on errors in configuration code

* Plug an unchecked error in gallery zip walking

* Warn on screenshot serving failure

* Warn on encoder screenshot failure

* Warn on errors in path-handling code

* Undo the errcheck on configurations for now.

* Use one-line initializers where applicable

rather than using

  err := f()
  if err!= nil { ..

prefer the shorter

  if err := f(); err != nil { ..

If f() isn't too long of a name, or wraps a function with a body.

pkg/manager/task_import.go

@@ -160,7 +160,9 @@ func (t *ImportTask) unzipFile() error {
 		fn := filepath.Join(t.BaseDir, f.Name)
 
 		if f.FileInfo().IsDir() {
-			os.MkdirAll(fn, os.ModePerm)
+			if err := os.MkdirAll(fn, os.ModePerm); err != nil {
+				logger.Warnf("couldn't create directory %v while unzipping import file: %v", fn, err)
+			}
 			continue
 		}