update go-plugin package

Fixes a minor issue where the plugin may be closed before the stderr
reader completes, resulting in a warning in the logs.

go.mod

@@ -51,7 +51,7 @@ require (
 	github.com/hashicorp/go-immutable-radix v0.0.0-20180129170900-7f3cd4390caa // indirect
 	github.com/hashicorp/go-msgpack v0.5.4 // indirect
 	github.com/hashicorp/go-multierror v1.0.0
-	github.com/hashicorp/go-plugin v1.0.1-0.20190430211030-5692942914bb
+	github.com/hashicorp/go-plugin v1.0.1-0.20190610192547-a1bc61569a26
 	github.com/hashicorp/go-retryablehttp v0.5.2
 	github.com/hashicorp/go-rootcerts v1.0.0
 	github.com/hashicorp/go-sockaddr v0.0.0-20180320115054-6d291a969b86 // indirect

go.sum

@@ -185,6 +185,8 @@ github.com/hashicorp/go-multierror v1.0.0 h1:iVjPR7a6H0tWELX5NxNe7bYopibicUzc7uP
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
 github.com/hashicorp/go-plugin v1.0.1-0.20190430211030-5692942914bb h1:Zg2pmmk0lrLFL85lQGt08bOUBpIBaVs6/psiAyx0c4w=
 github.com/hashicorp/go-plugin v1.0.1-0.20190430211030-5692942914bb/go.mod h1:++UyYGoz3o5w9ZzAdZxtQKrWWP+iqPBn3cQptSMzBuY=
+github.com/hashicorp/go-plugin v1.0.1-0.20190610192547-a1bc61569a26 h1:hRho44SAoNu1CBtn5r8Q9J3rCs4ZverWZ4R+UeeNuWM=
+github.com/hashicorp/go-plugin v1.0.1-0.20190610192547-a1bc61569a26/go.mod h1:++UyYGoz3o5w9ZzAdZxtQKrWWP+iqPBn3cQptSMzBuY=
 github.com/hashicorp/go-retryablehttp v0.5.2 h1:AoISa4P4IsW0/m4T6St8Yw38gTl5GtBAgfkhYh1xAz4=
 github.com/hashicorp/go-retryablehttp v0.5.2/go.mod h1:9B5zBasrRhHXnJnui7y6sL7es7NDiJgTc6Er0maI1Xs=
 github.com/hashicorp/go-rootcerts v1.0.0 h1:Rqb66Oo1X/eSV1x66xbDccZjhJigjg0+e82kpwzSwCI=

vendor/github.com/hashicorp/go-plugin/client.go

@@ -87,6 +87,10 @@ type Client struct {
 	// goroutines.
 	clientWaitGroup sync.WaitGroup
 
+	// stderrWaitGroup is used to prevent the command's Wait() function from
+	// being called before we've finished reading from the stderr pipe.
+	stderrWaitGroup sync.WaitGroup
+
 	// processKilled is used for testing only, to flag when the process was
 	// forcefully killed.
 	processKilled bool
@@ -590,6 +594,12 @@ func (c *Client) Start() (addr net.Addr, err error) {
 	// Create a context for when we kill
 	c.doneCtx, c.ctxCancel = context.WithCancel(context.Background())
 
+	// Start goroutine that logs the stderr
+	c.clientWaitGroup.Add(1)
+	c.stderrWaitGroup.Add(1)
+	// logStderr calls Done()
+	go c.logStderr(cmdStderr)
+
 	c.clientWaitGroup.Add(1)
 	go func() {
 		// ensure the context is cancelled when we're done
@@ -602,6 +612,10 @@ func (c *Client) Start() (addr net.Addr, err error) {
 		pid := c.process.Pid
 		path := cmd.Path
 
+		// wait to finish reading from stderr since the stderr pipe reader
+		// will be closed by the subsequent call to cmd.Wait().
+		c.stderrWaitGroup.Wait()
+
 		// Wait for the command to end.
 		err := cmd.Wait()
 
@@ -624,11 +638,6 @@ func (c *Client) Start() (addr net.Addr, err error) {
 		c.exited = true
 	}()
 
-	// Start goroutine that logs the stderr
-	c.clientWaitGroup.Add(1)
-	// logStderr calls Done()
-	go c.logStderr(cmdStderr)
-
 	// Start a goroutine that is going to be reading the lines
 	// out of stdout
 	linesCh := make(chan string)
@@ -936,6 +945,7 @@ var stdErrBufferSize = 64 * 1024
 
 func (c *Client) logStderr(r io.Reader) {
 	defer c.clientWaitGroup.Done()
+	defer c.stderrWaitGroup.Done()
 	l := c.logger.Named(filepath.Base(c.config.Cmd.Path))
 
 	reader := bufio.NewReaderSize(r, stdErrBufferSize)

vendor/github.com/hashicorp/go-plugin/server.go

@@ -363,14 +363,34 @@ func serverListener() (net.Listener, error) {
 }
 
 func serverListener_tcp() (net.Listener, error) {
-	minPort, err := strconv.ParseInt(os.Getenv("PLUGIN_MIN_PORT"), 10, 32)
-	if err != nil {
-		return nil, err
+	envMinPort := os.Getenv("PLUGIN_MIN_PORT")
+	envMaxPort := os.Getenv("PLUGIN_MAX_PORT")
+
+	var minPort, maxPort int64
+	var err error
+
+	switch {
+	case len(envMinPort) == 0:
+		minPort = 0
+	default:
+		minPort, err = strconv.ParseInt(envMinPort, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("Couldn't get value from PLUGIN_MIN_PORT: %v", err)
+		}
 	}
 
-	maxPort, err := strconv.ParseInt(os.Getenv("PLUGIN_MAX_PORT"), 10, 32)
-	if err != nil {
-		return nil, err
+	switch {
+	case len(envMaxPort) == 0:
+		maxPort = 0
+	default:
+		maxPort, err = strconv.ParseInt(envMaxPort, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("Couldn't get value from PLUGIN_MAX_PORT: %v", err)
+		}
+	}
+
+	if minPort > maxPort {
+		return nil, fmt.Errorf("ENV_MIN_PORT value of %d is greater than PLUGIN_MAX_PORT value of %d", minPort, maxPort)
 	}
 
 	for port := minPort; port <= maxPort; port++ {

vendor/modules.txt

@@ -280,7 +280,7 @@ github.com/hashicorp/go-getter/helper/url
 github.com/hashicorp/go-hclog
 # github.com/hashicorp/go-multierror v1.0.0
 github.com/hashicorp/go-multierror
-# github.com/hashicorp/go-plugin v1.0.1-0.20190430211030-5692942914bb
+# github.com/hashicorp/go-plugin v1.0.1-0.20190610192547-a1bc61569a26
 github.com/hashicorp/go-plugin
 github.com/hashicorp/go-plugin/internal/plugin
 # github.com/hashicorp/go-retryablehttp v0.5.2