feat(cli): fine-grained log level (#3703)

.github/ISSUE_TEMPLATE/bug_report.md

@@ -16,7 +16,7 @@ Please review the [Community Note](https://github.com/trufflesecurity/trufflehog
 <!---
 Please provide a link to a GitHub Gist containing the complete debug output. Please do NOT paste the debug output in the issue; just paste a link to the Gist.
 
-To obtain the trace output, run trufflehog with the --trace flag.
+To obtain the trace output, run trufflehog with the --log-level=5 flag.
 --->
 
 ### Expected Behavior

Makefile

@@ -12,7 +12,7 @@ PROTOS_IMAGE ?= trufflesecurity/protos:1.22
 .PHONY: dogfood
 
 dogfood:
-	CGO_ENABLED=0 go run . git file://. --json --debug
+	CGO_ENABLED=0 go run . git file://. --json --log-level=2
 
 install:
 	CGO_ENABLED=0 go install .
@@ -49,7 +49,7 @@ run:
 	CGO_ENABLED=0 go run . git file://. --json
 
 run-debug:
-	CGO_ENABLED=0 go run . git file://. --json --debug
+	CGO_ENABLED=0 go run . git file://. --json --log-level=2
 
 protos:
 	docker run --rm -u "$(shell id -u)" -v "$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))":/pwd "${PROTOS_IMAGE}" bash -c "cd /pwd; /pwd/scripts/gen_proto.sh"

README.md

@@ -410,8 +410,7 @@ Find credentials in git repositories.
 
 Flags:
   -h, --help                Show context-sensitive help (also try --help-long and --help-man).
-      --debug               Run in debug mode.
-      --trace               Run in trace mode.
+      --log-level=0         Logging verbosity on a scale of 0 (info) to 5 (trace). Can be disabled with "-1".
       --profile             Enables profiling and sets a pprof and fgprof server on :18066.
   -j, --json                Output in JSON format.
       --json-legacy         Use the pre-v3.0 JSON format. Only works with git, gitlab, and github sources.
@@ -567,7 +566,7 @@ TruffleHog statically detects [https://canarytokens.org/](https://canarytokens.o
     # Scan commits until here (usually dev branch).
     head: # optional
     # Extra args to be passed to the trufflehog cli.
-    extra_args: --debug --only-verified
+    extra_args: --log-level=2 --only-verified
 ```
 
 If you'd like to specify specific `base` and `head` refs, you can use the `base` argument (`--since-commit` flag in TruffleHog CLI) and the `head` argument (`--branch` flag in the TruffleHog CLI). We only recommend using these arguments for very specific use cases, where the default behavior does not work.

main.go

@@ -40,10 +40,12 @@ import (
 )
 
 var (
-	cli                 = kingpin.New("TruffleHog", "TruffleHog is a tool for finding credentials.")
-	cmd                 string
-	debug               = cli.Flag("debug", "Run in debug mode.").Bool()
-	trace               = cli.Flag("trace", "Run in trace mode.").Bool()
+	cli = kingpin.New("TruffleHog", "TruffleHog is a tool for finding credentials.")
+	cmd string
+	// https://github.com/trufflesecurity/trufflehog/blob/main/CONTRIBUTING.md#logging-in-trufflehog
+	logLevel            = cli.Flag("log-level", `Logging verbosity on a scale of 0 (info) to 5 (trace). Can be disabled with "-1".`).Default("0").Int()
+	debug               = cli.Flag("debug", "Run in debug mode.").Hidden().Bool()
+	trace               = cli.Flag("trace", "Run in trace mode.").Hidden().Bool()
 	profile             = cli.Flag("profile", "Enables profiling and sets a pprof and fgprof server on :18066.").Bool()
 	localDev            = cli.Flag("local-dev", "Hidden feature to disable overseer for local dev.").Hidden().Bool()
 	jsonOut             = cli.Flag("json", "Output in JSON format.").Short('j').Bool()
@@ -275,11 +277,26 @@ func init() {
 
 	cmd = kingpin.MustParse(cli.Parse(os.Args[1:]))
 
+	// Configure logging.
 	switch {
 	case *trace:
 		log.SetLevel(5)
 	case *debug:
 		log.SetLevel(2)
+	default:
+		l := int8(*logLevel)
+		if l < -1 || l > 5 {
+			fmt.Fprintf(os.Stderr, "invalid log level: %d\n", *logLevel)
+			os.Exit(1)
+		}
+
+		if l == -1 {
+			// Zap uses "5" as the value for fatal.
+			// We need to pass in "-5" because `SetLevel` passes the negation.
+			log.SetLevel(-5)
+		} else {
+			log.SetLevel(l)
+		}
 	}
 }