From 9c8b3825be31236264407848b144e097b5935b98 Mon Sep 17 00:00:00 2001
From: Robert Parker <parrobe@uk.ibm.com>
Date: Wed, 12 Dec 2018 13:11:47 +0000
Subject: [PATCH] Add image tag into info output, add ability to print info
 output on demand and prevent multiple instances of runmqserver being run

---
 Dockerfile-server                           |  3 +-
 Makefile-UBUNTU                             |  3 +-
 cmd/runmqserver/main.go                     | 20 +++++++
 cmd/runmqserver/process.go                  | 63 +++++++++++++++++++++
 cmd/runmqserver/version.go                  |  7 +++
 incubating/mqadvanced-server-dev/Dockerfile |  3 +-
 6 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 cmd/runmqserver/process.go

diff --git a/Dockerfile-server b/Dockerfile-server
index ba81c0c..97d70e9 100644
--- a/Dockerfile-server
+++ b/Dockerfile-server
@@ -22,10 +22,11 @@ FROM $BUILDER_IMAGE as builder
 WORKDIR /go/src/github.com/ibm-messaging/mq-container/
 ARG IMAGE_REVISION="Not specified"
 ARG IMAGE_SOURCE="Not specified"
+ARG IMAGE_TAG="Not specified"
 COPY cmd/ ./cmd
 COPY internal/ ./internal
 COPY vendor/ ./vendor
-RUN go build -ldflags "-X \"main.ImageCreated=$(date --iso-8601=seconds)\" -X \"main.ImageRevision=$IMAGE_REVISION\" -X \"main.ImageSource=$IMAGE_SOURCE\"" ./cmd/runmqserver/
+RUN go build -ldflags "-X \"main.ImageCreated=$(date --iso-8601=seconds)\" -X \"main.ImageRevision=$IMAGE_REVISION\" -X \"main.ImageSource=$IMAGE_SOURCE\" -X \"main.ImageTag=$IMAGE_TAG\"" ./cmd/runmqserver/
 RUN go build ./cmd/chkmqready/
 RUN go build ./cmd/chkmqhealthy/
 # Run all unit tests
diff --git a/Makefile-UBUNTU b/Makefile-UBUNTU
index 71a76b1..0ca502e 100644
--- a/Makefile-UBUNTU
+++ b/Makefile-UBUNTU
@@ -205,6 +205,7 @@ define docker-build-mq
 	  --build-arg BUILDER_IMAGE=$(MQ_IMAGE_GOLANG_SDK) \
 	  --build-arg IMAGE_REVISION="$(IMAGE_REVISION)" \
 	  --build-arg IMAGE_SOURCE="$(IMAGE_SOURCE)" \
+	  --build-arg IMAGE_TAG="$1" \
 	  --label IBM_PRODUCT_ID=$4 \
 	  --label IBM_PRODUCT_NAME=$5 \
 	  --label IBM_PRODUCT_VERSION=$6 \
@@ -236,7 +237,7 @@ build-devserver: MQ_SDK_ARCHIVE=$(MQ_ARCHIVE_DEV)
 build-devserver: downloads/$(MQ_ARCHIVE_DEV) docker-version build-golang-sdk-ex
 	$(info $(shell printf $(TITLE)"Build $(MQ_IMAGE_DEVSERVER_BASE)"$(END)))
 	$(call docker-build-mq,$(MQ_IMAGE_DEVSERVER_BASE),Dockerfile-server,$(MQ_ARCHIVE_DEV),"98102d16795c4263ad9ca075190a2d4d","IBM MQ Advanced for Developers (Non-Warranted)",$(MQ_VERSION))
-	$(DOCKER) build --tag $(MQ_IMAGE_DEVSERVER) --build-arg IMAGE_SOURCE="$(IMAGE_SOURCE)" --build-arg IMAGE_REVISION="$(IMAGE_REVISION)" --build-arg BASE_IMAGE=$(MQ_IMAGE_DEVSERVER_BASE) --build-arg BUILDER_IMAGE=$(MQ_IMAGE_GOLANG_SDK) --file incubating/mqadvanced-server-dev/Dockerfile .
+	$(DOCKER) build --tag $(MQ_IMAGE_DEVSERVER) --build-arg IMAGE_SOURCE="$(IMAGE_SOURCE)" --build-arg IMAGE_REVISION="$(IMAGE_REVISION)" --build-arg IMAGE_TAG="$(MQ_IMAGE_DEVSERVER)" --build-arg BASE_IMAGE=$(MQ_IMAGE_DEVSERVER_BASE) --build-arg BUILDER_IMAGE=$(MQ_IMAGE_GOLANG_SDK) --file incubating/mqadvanced-server-dev/Dockerfile .
 
 .PHONY: build-advancedserver-cover
 build-advancedserver-cover: docker-version
diff --git a/cmd/runmqserver/main.go b/cmd/runmqserver/main.go
index 4df645b..01f00d5 100644
--- a/cmd/runmqserver/main.go
+++ b/cmd/runmqserver/main.go
@@ -20,6 +20,7 @@ package main
 import (
 	"context"
 	"errors"
+	"flag"
 	"os"
 	"sync"
 
@@ -29,12 +30,31 @@ import (
 )
 
 func doMain() error {
+	var infoFlag = flag.Bool("info", false, "Display debug info, then exit")
+	flag.Parse()
+
+	// Configure the logger so we can output messages
 	name, nameErr := name.GetQueueManagerName()
 	mf, err := configureLogger(name)
 	if err != nil {
 		logTermination(err)
 		return err
 	}
+
+	// Check whether they only want debug info
+	if *infoFlag {
+		logVersionInfo()
+		logConfig()
+		return nil
+	}
+
+	err = verifySingleProcess()
+	if err != nil {
+		// We don't do the normal termination here as it would create a termination file.
+		log.Error(err)
+		return err
+	}
+
 	if nameErr != nil {
 		logTermination(err)
 		return err
diff --git a/cmd/runmqserver/process.go b/cmd/runmqserver/process.go
new file mode 100644
index 0000000..03d6c56
--- /dev/null
+++ b/cmd/runmqserver/process.go
@@ -0,0 +1,63 @@
+/*
+© Copyright IBM Corporation 2018
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/ibm-messaging/mq-container/internal/command"
+)
+
+// Verifies that we are the main or only instance of this program
+func verifySingleProcess() error {
+	programName, err := determineExecutable()
+	if err != nil {
+		return fmt.Errorf("Failed to determine name of this program - %v", err)
+	}
+
+	// Verify that there is only one runmqserver
+	_, err = verifyOnlyOne(programName)
+	if err != nil {
+		return fmt.Errorf("You cannot run more than one instance of this program")
+	}
+
+	return nil
+}
+
+// Verifies that there is only one instance running of the given program name.
+func verifyOnlyOne(programName string) (int, error) {
+	out, _, _ := command.Run("ps", "-e", "--format", "cmd")
+	//if this goes wrong then assume we are the only one
+	numOfProg := strings.Count(out, programName)
+	if numOfProg != 1 {
+		return numOfProg, fmt.Errorf("Expected there to be only 1 instance of %s but found %d", programName, numOfProg)
+	}
+	return numOfProg, nil
+}
+
+// Determines the name of the currently running executable.
+func determineExecutable() (string, error) {
+	file, err := os.Executable()
+	if err != nil {
+		return "", err
+	}
+
+	_, exec := filepath.Split(file)
+	return exec, nil
+}
diff --git a/cmd/runmqserver/version.go b/cmd/runmqserver/version.go
index 35af770..0142364 100644
--- a/cmd/runmqserver/version.go
+++ b/cmd/runmqserver/version.go
@@ -29,6 +29,8 @@ var (
 	ImageRevision = "Not specified"
 	// ImageSource is the URL to get source code for building the image
 	ImageSource = "Not specified"
+	// ImageTag is the tag of the image
+	ImageTag = "Not specified"
 )
 
 func logDateStamp() {
@@ -43,6 +45,10 @@ func logGitCommit() {
 	log.Printf("Image source: %v", ImageSource)
 }
 
+func logImageTag() {
+	log.Printf("Image tag: %v", ImageTag)
+}
+
 func logMQVersion() {
 	mqVersion, _, err := command.Run("dspmqver", "-b", "-f", "2")
 	if err != nil {
@@ -67,5 +73,6 @@ func logVersionInfo() {
 	logDateStamp()
 	logGitRepo()
 	logGitCommit()
+	logImageTag()
 	logMQVersion()
 }
diff --git a/incubating/mqadvanced-server-dev/Dockerfile b/incubating/mqadvanced-server-dev/Dockerfile
index 148635a..2c996d8 100644
--- a/incubating/mqadvanced-server-dev/Dockerfile
+++ b/incubating/mqadvanced-server-dev/Dockerfile
@@ -21,12 +21,13 @@ ARG BUILDER_IMAGE=mq-golang-sdk:9.1.1.0-x86_64-ubuntu-16.04
 FROM $BUILDER_IMAGE as builder
 ARG IMAGE_REVISION="Not specified"
 ARG IMAGE_SOURCE="Not specified"
+ARG IMAGE_TAG="Not specified"
 WORKDIR /go/src/github.com/ibm-messaging/mq-container/
 COPY cmd/ ./cmd
 COPY internal/ ./internal
 COPY vendor/ ./vendor
 # Re-build runmqserver, with code tagged with 'mqdev' enabled
-RUN go build -ldflags "-X \"main.ImageCreated=$(date --iso-8601=seconds)\" -X \"main.ImageRevision=$IMAGE_REVISION\" -X \"main.ImageSource=$IMAGE_SOURCE\"" --tags 'mqdev'  ./cmd/runmqserver
+RUN go build -ldflags "-X \"main.ImageCreated=$(date --iso-8601=seconds)\" -X \"main.ImageRevision=$IMAGE_REVISION\" -X \"main.ImageSource=$IMAGE_SOURCE\" -X \"main.ImageTag=$IMAGE_TAG\"" --tags 'mqdev'  ./cmd/runmqserver
 RUN go build ./cmd/runmqdevserver/
 # Run all unit tests
 RUN go test -v ./cmd/runmqdevserver/...