Enhance ParseDuration with configurable parsing options

Introduce ParseDuration() as the primary and simplest entrypoint for
parsing durations

.gitignore

@@ -19,3 +19,4 @@
 
 # Go workspace file
 go.work
+/haproxytimeout

Makefile

@@ -0,0 +1,23 @@
+DATE		:= $(shell date --iso-8601=seconds)
+GOVERSION	:= $(shell go version)
+COMMIT		:= $(shell git describe --tags --abbrev=8 --dirty --always --long)
+
+PREFIX		:= main
+LDFLAGS		:= -X '$(PREFIX).buildCommit=$(COMMIT)' -X '$(PREFIX).buildDate=$(DATE)' -X '$(PREFIX).buildGoVersion=$(GOVERSION)'
+
+build: test lint
+	go build -ldflags "$(LDFLAGS)" -o ./haproxytimeout ./cmd/haproxytimeout
+
+test:
+	go test ./...
+
+lint:
+	golangci-lint run ./...
+
+benchmark:
+	go test -bench=. -benchmem -count=5 -benchtime=1s
+
+clean:
+	$(RM) ./haproxytimeout ./haproxytimeout.test
+
+.PHONY: build test clean benchmark lint

README.md

@@ -1,62 +1,19 @@
-# parse time durations, with support for days
+# Parse time durations, with support for days
 
-This is a Go library that parses duration strings in a format similar
-to time.ParseDuration, with the additional capability of handling
-duration strings specifying a number of days ("d"). This functionality
-is not available in the built-in time.ParseDuration function. It also
-differs by not accepting negative values. This package was primarily
-created for validating HAProxy timeout values.
+A Go library to parse time duration values similar to
+time.ParseDuration, but with extended functionality. In addition to
+the standard duration units like "h", "m", and "s", it also supports
+days (represented as "d"), which are unavailable in the built-in
+time.ParseDuration function. All durations parsed by this package are
+ensured to be non-negative and won't overflow the time.Duration value
+type. Furthermore, a parsed duration value cannot exceed HAProxy's
+maximum timeout.
 
-The CLI utility `haproxy-timeout-checker` is an example of using the
-package. It validates the time duration using `ParseDuration` and also
-checks to see if the duration exceeds HAProxy's maximum.
+The command line utility `haproxytimeout` is an example of using the
+package but also serves to convert human-readable duration values to
+microseconds, suitable for a HAProxy configuration file.
 
 ```console
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "9223372036s"
-duration 9223372036000ms exceeds HAProxy's maximum value of 2147483647ms
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "2147483647ms"
-2147483647
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "2147483648ms"
-duration 2147483648ms exceeds HAProxy's maximum value of 2147483647ms
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d"
-86400000
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d 1s"
-86401000
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d 3h 10m 20s 100ms 9999us"
-97820109
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go 5000
-5000
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "5000 999999ms"
-5000 999999ms
-            ^
-error: invalid unit order
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d 1f"
-1d 1f
-    ^
-error: invalid unit
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d 1d"
-1d 1d
-    ^
-error: invalid unit order
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d 5m 1230ms"
-86701230
-
-# Note: Spaces are optional.
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "1d5m"
-86700000
-
-$ go run cmd/haproxy-timeout-checker/haproxy-timeout-checker.go "9223372037s"
-9223372037s
-          ^
-error: underflow
+$ make
+$ ./haproxytimeout -help
 ```