fix #136: add Go 1.10; fix #135: integrate with scrutinizer; fix #134: add quick start example;

Author: kamilsk

.gitignore

@@ -1,11 +1,8 @@
-# glide from docker
-.glide/
-
-# dep, glide
+# dep
 vendor/
 
 # goreleaser
 /dist/
 
-# go test, code quality report
+# go test and code quality report
 *.out

.goreleaser.yml

@@ -24,7 +24,7 @@ brew:
   github:
     name:  homebrew-tap
     owner: kamilsk
-  homepage:    https://github.com/kamilsk/semaphore
+  homepage: https://github.com/kamilsk/semaphore
 
 build:
   binary: semaphore
@@ -38,7 +38,7 @@ build:
   - linux
   - windows
   ldflags: -s -w -X main.version={{.Version}} -X main.commit={{.Commit}} -X main.date={{.Date}}
-  main:    ./cmd/semaphore
+  main: ./cmd/semaphore
 
 checksum: { name_template: checksums.txt }
 

.scrutinizer.yml

@@ -0,0 +1,21 @@
+build:
+  dependencies:
+    override:
+    - export DEP_VERSION=0.4.1; wget -q -O dep https://github.com/golang/dep/releases/download/v${DEP_VERSION}/dep-linux-amd64 && chmod +x dep && mv dep "${GOPATH}"/bin; make cmd-deps-local
+
+  environment:
+    go: go1.9
+
+  nodes:
+    analysis:
+      tests:
+        override:
+        - go-scrutinizer-run
+        - golint-run
+
+  tests:
+    override:
+    - make test
+
+checks:
+  go: true

.travis.yml

@@ -1,13 +1,14 @@
 language: go
 
 go:
+- master
+- 1.x
 - 1.5.x
 - 1.6.x
 - 1.7.x
 - 1.8.x
 - 1.9.x
-- 1.x
-- master
+- 1.10.x
 
 matrix:
   allow_failures:
@@ -17,12 +18,14 @@ matrix:
 sudo: false
 
 before_install:
-- wget -q -O dep https://github.com/golang/dep/releases/download/v0.3.2/dep-linux-amd64
-- chmod +x dep && mv dep "${GOPATH}"/bin
-- go get github.com/mattn/goveralls
+- export DEP_VERSION=0.4.1
 - export GO_TEST_COVERAGE_FILENAME='coverage.out'
 - export GO15VENDOREXPERIMENT=1
 
+- wget -q -O dep https://github.com/golang/dep/releases/download/v${DEP_VERSION}/dep-linux-amd64
+- chmod +x dep && mv dep "${GOPATH}"/bin
+- go get github.com/mattn/goveralls
+
 install:
 - make cmd-deps-local
 
@@ -32,6 +35,7 @@ script:
 after_success:
 - goveralls -service=travis-ci -coverprofile="${GO_TEST_COVERAGE_FILENAME}"
 - echo $TRAVIS_GO_VERSION ":" $TRAVIS_TAG
+# TODO wait https://github.com/travis-ci/gimme/pull/130
 - if [[ $TRAVIS_GO_VERSION == 1.9* ]] && [ -n "$TRAVIS_TAG" ]; then curl -sL https://git.io/goreleaser | bash; fi
 
 notifications:

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017 OctoLab, https://www.octolab.org/ <feedback@octolab.org>
+Copyright (c) 2018 OctoLab, https://www.octolab.org/ <feedback@octolab.org>
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,5 +1,5 @@
 > # semaphore [![Tweet](https://img.shields.io/twitter/url/http/shields.io.svg?style=social)](https://twitter.com/intent/tweet?text=Semaphore%20pattern%20implementation%20with%20a%20timeout%20of%20lock%2Funlock%20operations%20based%20on%20channels&url=https://github.com/kamilsk/semaphore&via=ikamilsk&hashtags=go,semaphore,throughput,limiter)
-> [![Analytics](https://ga-beacon.appspot.com/UA-109817251-2/semaphore/dev?pixel)](https://github.com/igrigorik/ga-beacon)
+> [![Analytics](https://ga-beacon.appspot.com/UA-109817251-2/semaphore/dev?pixel)](https://github.com/kamilsk/semaphore)
 > Semaphore pattern implementation with timeout of lock/unlock operations based on channels.
 
 [![Awesome](https://cdn.rawgit.com/sindresorhus/awesome/d7305f38d29fed78fa85652e3a63e154dd8e8829/media/badge.svg)](https://github.com/avelino/awesome-go#goroutines)
@@ -12,6 +12,23 @@
 
 ## Usage
 
+### Quick start
+
+```go
+limiter := semaphore.New(1000)
+
+http.HandleFunc("/", func(rw http.ResponseWriter, _ *http.Request) {
+	if _, err := limiter.Acquire(semaphore.WithTimeout(time.Minute)); err != nil {
+		http.Error(rw, http.StatusText(http.StatusTooManyRequests), http.StatusTooManyRequests)
+		return
+	}
+	defer limiter.Release()
+	// handle request
+})
+
+log.Fatal(http.ListenAndServe(":80", nil))
+```
+
 ### Console tool for command execution in parallel
 
 This example shows how to execute many console commands in parallel.
@@ -256,5 +273,5 @@ use [dep](https://github.com/golang/dep) or something similar for this purpose.
 ## Notes
 
 - [research](../../tree/research)
-- tested on Go 1.5, 1.6, 1.7, 1.8 and 1.9
+- tested on Go 1.5, 1.6, 1.7, 1.8, 1.9 and 1.10
 - made with ❤️ by [OctoLab](https://www.octolab.org/)

channel.go

@@ -8,6 +8,7 @@ import (
 )
 
 // Multiplex combines multiple empty struct channels into one.
+// TODO can be leaky, https://github.com/kamilsk/semaphore/issues/133
 func Multiplex(channels ...<-chan struct{}) <-chan struct{} {
 	ch := make(chan struct{})
 	if len(channels) == 0 {
@@ -25,13 +26,29 @@ func Multiplex(channels ...<-chan struct{}) <-chan struct{} {
 	return ch
 }
 
-// WithDeadline returns empty struct channel based on Time channel.
+// WithDeadline returns empty struct channel above on `time.Timer` channel.
+// TODO can be leaky, https://github.com/kamilsk/semaphore/issues/133
 func WithDeadline(deadline time.Time) <-chan struct{} {
-	// go 1.5 doesn't support time.Until(deadline)
-	return WithTimeout(deadline.Sub(time.Now())) //nolint: gosimple
+	ch := make(chan struct{})
+	if time.Now().After(deadline) {
+		close(ch)
+		return ch
+	}
+	go func() {
+		// go 1.5 doesn't support time.Until(deadline)
+		after := deadline.Sub(time.Now()) //nolint: gosimple
+		if after <= 0 {
+			close(ch)
+			return
+		}
+		<-time.After(after)
+		close(ch)
+	}()
+	return ch
 }
 
-// WithSignal returns empty struct channel based on Signal channel.
+// WithSignal returns empty struct channel above on `os.Signal` channel.
+// TODO can be leaky, https://github.com/kamilsk/semaphore/issues/133
 func WithSignal(s os.Signal) <-chan struct{} {
 	ch := make(chan struct{})
 	if s == nil {
@@ -48,16 +65,13 @@ func WithSignal(s os.Signal) <-chan struct{} {
 	return ch
 }
 
-// WithTimeout returns empty struct channel based on Time channel.
+// WithTimeout returns empty struct channel above on `time.Timer` channel.
+// TODO can be leaky, https://github.com/kamilsk/semaphore/issues/133
 func WithTimeout(timeout time.Duration) <-chan struct{} {
 	ch := make(chan struct{})
 	if timeout <= 0 {
 		close(ch)
 		return ch
 	}
-	go func() {
-		<-time.After(timeout)
-		close(ch)
-	}()
-	return ch
+	return WithDeadline(time.Now().Add(timeout))
 }

context.go

@@ -8,6 +8,9 @@ import "context"
 func WithContext(parent context.Context, deadline <-chan struct{}) context.Context {
 	ctx, cancel := context.WithCancel(parent)
 	go func() {
+		if deadline == nil {
+			return
+		}
 		<-deadline
 		cancel()
 	}()