consullocker: Remove unused package

.scripts/test_all.sh

@@ -5,7 +5,7 @@ set -e
 # Find all packages containing Go source code inside the current directory
 packages=$(find ./ -maxdepth 2 -name '*.go' -printf '%h\n' | sort | uniq)
 
-# The consul package only supports Go1.10+ and therefore we will only run the
+# Some packages only support Go1.10+ and therefore we will only run the
 # corresponding tests on these versions.
 goversion=$(go version)
 if [[ "$goversion" == *"go1.5"* ]] ||
@@ -14,19 +14,12 @@ if [[ "$goversion" == *"go1.5"* ]] ||
    [[ "$goversion" == *"go1.8"* ]] ||
    [[ "$goversion" == *"go1.9"* ]]; then
 
-  echo "Skipping tests requiring Consul which is not supported on $goversion"
-
-  # Exclude consullocker since this may not be run on all Go versions.
-  packages=$(echo "$packages" | sed '/consul/d')
-
   echo "Skipping tests requiring GCSStore, which is not supported on $goversion"
   packages=$(echo "$packages" | sed '/gcsstore/d')
 
   echo "Skipping tests requiring Prometheus, which is not supported on $goversion"
   packages=$(echo "$packages" | sed '/prometheuscollector/d')
 else
-  # Install the Consul and Prometheus client packages which are not vendored.
-  go get -u github.com/hashicorp/consul/...
   go get -u github.com/prometheus/client_golang/prometheus
 fi
 

README.md

@@ -226,7 +226,6 @@ useful tools:
 * [**filestore**](https://godoc.org/github.com/tus/tusd/filestore): A storage backend using the local file system
 * [**gcsstore**](https://godoc.org/github.com/tus/tusd/gcsstore): A storage backend using Google cloud storage
 * [**memorylocker**](https://godoc.org/github.com/tus/tusd/memorylocker): An in-memory locker for handling concurrent uploads
-* [**consullocker**](https://godoc.org/github.com/tus/tusd/consullocker): A locker using the distributed Consul service
 * [**etcd3locker**](https://godoc.org/github.com/tus/tusd/etcd3locker): A locker using the distributed KV etcd3 store
 * [**limitedstore**](https://godoc.org/github.com/tus/tusd/limitedstore): A storage wrapper limiting the total used space for uploads
 

consullocker/consullocker.go

@@ -1,122 +0,0 @@
-// Package consullocker provides a locking mechanism using a Consul server.
-//
-// Consul's (https://www.consul.io) key/value storage system can also be used
-// for building a distributed exclusive locking mechanism, often referred to
-// as leader election (https://www.consul.io/docs/guides/leader-election.html).
-//
-// Due to Consul being an external server, connection issues can occur between
-// tusd and Consul. In this situation, tusd cannot always ensure that it still
-// holds a lock and may panic in an unrecoverable way. This may seems like an
-// inconvenient decision but is probably the best solution since we are not
-// able to interrupt other goroutines which may be involved in moving the
-// uploaded data to a backend.
-package consullocker
-
-import (
-	"sync"
-	"time"
-
-	consul "github.com/hashicorp/consul/api"
-	"github.com/tus/tusd"
-)
-
-type ConsulLocker struct {
-	// Client used to connect to the Consul server
-	Client *consul.Client
-
-	// ConnectionName is an optional field which may contain a human-readable
-	// description for the connection. It is only used for composing error
-	// messages and can be used to match them to a specific Consul instance.
-	ConnectionName string
-
-	// locks is used for storing consul.Lock structs before they are unlocked.
-	// If you want to release a lock, you need the same consul.Lock instance
-	// and therefore we need to save them temporarily.
-	locks map[string]*consul.Lock
-	mutex *sync.RWMutex
-}
-
-// New constructs a new locker using the provided client.
-func New(client *consul.Client) *ConsulLocker {
-	return &ConsulLocker{
-		Client: client,
-		locks:  make(map[string]*consul.Lock),
-		mutex:  new(sync.RWMutex),
-	}
-}
-
-// UseIn adds this locker to the passed composer.
-func (locker *ConsulLocker) UseIn(composer *tusd.StoreComposer) {
-	composer.UseLocker(locker)
-}
-
-// LockUpload tries to obtain the exclusive lock.
-func (locker *ConsulLocker) LockUpload(id string) error {
-	lock, err := locker.Client.LockOpts(&consul.LockOptions{
-		Key:          id + "/" + consul.DefaultSemaphoreKey,
-		LockTryOnce:  true,
-		LockWaitTime: time.Second,
-	})
-	if err != nil {
-		return err
-	}
-
-	ch, err := lock.Lock(nil)
-	if ch == nil {
-		if err == nil || err == consul.ErrLockHeld {
-			return tusd.ErrFileLocked
-		} else {
-			return err
-		}
-	}
-
-	locker.mutex.Lock()
-	defer locker.mutex.Unlock()
-	// Only add the lock to our list if the acquire was successful and no error appeared.
-	locker.locks[id] = lock
-
-	go func() {
-		// This channel will be closed once we lost the lock. This can either happen
-		// wanted (using the Unlock method) or by accident, e.g. if the connection
-		// to the Consul server is lost.
-		<-ch
-
-		locker.mutex.RLock()
-		defer locker.mutex.RUnlock()
-		// Only proceed if the lock has been lost by accident. If we cannot find it
-		// in the map, it has already been gracefully removed (see UnlockUpload).
-		if _, ok := locker.locks[id]; !ok {
-			return
-		}
-
-		msg := "consullocker: lock for upload '" + id + "' has been lost."
-		if locker.ConnectionName != "" {
-			msg += " Please ensure that the connection to '" + locker.ConnectionName + "' is stable."
-		} else {
-			msg += " Please ensure that the connection to Consul is stable (use ConnectionName to provide a printable name)."
-		}
-
-		// This will cause the program to crash since a panic can only be recovered
-		// from the causing goroutine.
-		panic(msg)
-	}()
-
-	return nil
-}
-
-// UnlockUpload releases a lock.
-func (locker *ConsulLocker) UnlockUpload(id string) error {
-	locker.mutex.Lock()
-	defer locker.mutex.Unlock()
-
-	// Complain if no lock has been found. This can only happen if LockUpload
-	// has not been invoked before or UnlockUpload multiple times.
-	lock, ok := locker.locks[id]
-	if !ok {
-		return consul.ErrLockNotHeld
-	}
-
-	defer delete(locker.locks, id)
-
-	return lock.Unlock()
-}

consullocker/consullocker_test.go

@@ -1,61 +0,0 @@
-package consullocker
-
-import (
-	"testing"
-	"time"
-
-	consul "github.com/hashicorp/consul/api"
-	consultestutil "github.com/hashicorp/consul/sdk/testutil"
-	"github.com/stretchr/testify/assert"
-
-	"github.com/tus/tusd"
-)
-
-func TestConsulLocker(t *testing.T) {
-	a := assert.New(t)
-
-	server, err := consultestutil.NewTestServer()
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer server.Stop()
-
-	conf := consul.DefaultConfig()
-	conf.Address = server.HTTPAddr
-	client, err := consul.NewClient(conf)
-	a.NoError(err)
-
-	locker := New(client)
-
-	a.NoError(locker.LockUpload("one"))
-	a.Equal(tusd.ErrFileLocked, locker.LockUpload("one"))
-	a.NoError(locker.UnlockUpload("one"))
-	a.Equal(consul.ErrLockNotHeld, locker.UnlockUpload("one"))
-}
-
-func TestLockLost(t *testing.T) {
-	// This test will panic because the connection to Consul will be cut, which
-	// is indented.
-	// TODO: find a way to test this
-	t.SkipNow()
-
-	a := assert.New(t)
-
-	server, err := consultestutil.NewTestServer()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	client, err := consul.NewClient(&consul.Config{
-		Address: server.HTTPAddr,
-	})
-	a.NoError(err)
-
-	locker := New(client)
-	locker.ConnectionName = server.HTTPAddr
-
-	a.NoError(locker.LockUpload("two"))
-
-	server.Stop()
-	time.Sleep(time.Hour)
-}