[cipd] Enable specific log level.

cipd/client/cli/main.go

 // Copyright 2014 The LUCI Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 72 matching lines @@
         Refs []cipd.RefInfo `json:"refs"`
         Tags []cipd.TagInfo `json:"tags"`
 }
 
 // cipdSubcommand is a base of all CIPD subcommands. It defines some common
 // flags, such as logging and JSON output parameters.
 type cipdSubcommand struct {
         subcommands.CommandRunBase
 
         jsonOutput string
-        verbose    bool
+        logConfig  logging.Config
+
+        // TODO(dnj): Remove "verbose" flag once all current invocations of it are
+        // cleaned up and rolled out, as it is now deprecated in favor of "logConfig".
+        verbose bool
 }
 
 // ModifyContext implements cli.ContextModificator.
 func (c *cipdSubcommand) ModifyContext(ctx context.Context) context.Context {
         if c.verbose {
                 ctx = logging.SetLevel(ctx, logging.Debug)
+        } else {
+                ctx = c.logConfig.Set(ctx)
         }
         return ctx
 }
 
 // registerBaseFlags registers common flags used by all subcommands.
 func (c *cipdSubcommand) registerBaseFlags() {
+        // Set the default log level.
+        c.logConfig.Level = logging.Info
+
         c.Flags.StringVar(&c.jsonOutput, "json-output", "", "Path to write operation results to.")
-        c.Flags.BoolVar(&c.verbose, "verbose", false, "Enable more logging.")
+        c.Flags.BoolVar(&c.verbose, "verbose", false, "Enable more logging (deprecated, use -log-level=debug).")
+        c.logConfig.AddFlags(&c.Flags)
 }
 
 // checkArgs checks command line args.
 //
 // It ensures all required positional and flag-like parameters are set.
 // Returns true if they are, or false (and prints to stderr) if not.
 func (c *cipdSubcommand) checkArgs(args []string, minPosCount, maxPosCount int) bool {
         // Check number of expected positional arguments.
         if maxPosCount == 0 && len(args) != 0 {
                 c.printError(makeCLIError("unexpected arguments %v", args))
@@ skipping 2106 matching lines @@
 // subcommand invocations look more natural.
 //
 // Compare:
 //   * Default: cipd set-ref -ref=abc -version=def package/name
 //   * Improved: cipd set-ref package/name -ref=abc -version=def
 //
 // Much better.
 func Main(params Parameters, args []string) int {
         return subcommands.Run(GetApplication(params), fixFlagsPosition(args))
 }