从 Compute Engine 虚拟机连接到 Redis 实例

您可以从与 Redis 实例使用同一授权网络的 Compute Engine 虚拟机实例连接到该 Redis 实例。

设置

如果您已安装 Google Cloud CLI，并且已创建 Redis 实例和 Cloud Storage 存储桶，则可以跳过这些步骤。

1. 安装 gcloud CLI 并初始化：

   gcloud init
   

2. 按照快速入门指南创建一个 Redis 实例。记下该 Redis 实例的地区、IP 地址和端口。

3. 创建一个 Cloud Storage 存储分区，稍后将此示例应用的应用软件工件上传于此。有关详情，请参阅 创建存储分区。

配置示例应用的 gcloud 设置

1. 将 gcloud 默认项目设置为您的示例应用项目。

   gcloud config set project [PROJECT_ID]

示例应用

此示例 HTTP 服务器应用通过 Compute Engine 虚拟机实例建立与 Redis 实例的连接。

克隆您所需编程语言的代码库，并转到包含示例代码的文件夹：

Go

git clone https://github.com/GoogleCloudPlatform/golang-samples
cd golang-samples/memorystore/redis

Java

git clone https://github.com/GoogleCloudPlatform/java-docs-samples
cd java-docs-samples/memorystore/redis

Node.js

git clone https://github.com/GoogleCloudPlatform/nodejs-docs-samples
cd nodejs-docs-samples/memorystore/redis

Python

git clone https://github.com/GoogleCloudPlatform/python-docs-samples
cd python-docs-samples/memorystore/redis

每次访问 / 端点时，此示例应用都会增加一个 Redis 计数器。

Go

此应用使用 github.com/gomodule/redigo/redis 客户端。通过运行以下命令进行安装：

go get github.com/gomodule/redigo/redis

// Command redis is a basic app that connects to a managed Redis instance.
package main

import (
	"fmt"
	"log"
	"net/http"
	"os"

	"github.com/gomodule/redigo/redis"
)

var redisPool *redis.Pool

func incrementHandler(w http.ResponseWriter, r *http.Request) {
	conn := redisPool.Get()
	defer conn.Close()

	counter, err := redis.Int(conn.Do("INCR", "visits"))
	if err != nil {
		http.Error(w, "Error incrementing visitor counter", http.StatusInternalServerError)
		return
	}
	fmt.Fprintf(w, "Visitor number: %d", counter)
}

func main() {
	redisHost := os.Getenv("REDISHOST")
	redisPort := os.Getenv("REDISPORT")
	redisAddr := fmt.Sprintf("%s:%s", redisHost, redisPort)

	const maxConnections = 10
	redisPool = &redis.Pool{
		MaxIdle: maxConnections,
		Dial:    func() (redis.Conn, error) { return redis.Dial("tcp", redisAddr) },
	}

	http.HandleFunc("/", incrementHandler)

	port := os.Getenv("PORT")
	if port == "" {
		port = "8080"
	}
	log.Printf("Listening on port %s", port)
	if err := http.ListenAndServe(":"+port, nil); err != nil {
		log.Fatal(err)
	}
}

Java

此应用基于 Jetty 3.1 servlet。

它使用 Jedis 库：

<dependency>
  <groupId>redis.clients</groupId>
  <artifactId>jedis</artifactId>
  <version>5.1.0</version>
</dependency>

AppServletContextListener 类用于创建长效 Redis 连接池：

package com.example.redis;

import java.io.IOException;
import java.util.Properties;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

@WebListener
public class AppServletContextListener implements ServletContextListener {

  private Properties config = new Properties();

  private JedisPool createJedisPool() throws IOException {
    String host;
    Integer port;
    config.load(
        Thread.currentThread()
            .getContextClassLoader()
            .getResourceAsStream("application.properties"));
    host = config.getProperty("redis.host");
    port = Integer.valueOf(config.getProperty("redis.port", "6379"));

    JedisPoolConfig poolConfig = new JedisPoolConfig();
    // Default : 8, consider how many concurrent connections into Redis you will need under load
    poolConfig.setMaxTotal(128);

    return new JedisPool(poolConfig, host, port);
  }

  @Override
  public void contextDestroyed(ServletContextEvent event) {
    JedisPool jedisPool = (JedisPool) event.getServletContext().getAttribute("jedisPool");
    if (jedisPool != null) {
      jedisPool.destroy();
      event.getServletContext().setAttribute("jedisPool", null);
    }
  }

  // Run this before web application is started
  @Override
  public void contextInitialized(ServletContextEvent event) {
    JedisPool jedisPool = (JedisPool) event.getServletContext().getAttribute("jedisPool");
    if (jedisPool == null) {
      try {
        jedisPool = createJedisPool();
        event.getServletContext().setAttribute("jedisPool", jedisPool);
      } catch (IOException e) {
        // handle exception
      }
    }
  }
}

VisitCounterServlet 类是一个网络 Servlet，用于增加 Redis 计数器。

package com.example.redis;

import java.io.IOException;
import java.net.SocketException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

@WebServlet(name = "Track visits", value = "")
public class VisitCounterServlet extends HttpServlet {

  @Override
  public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    try {
      JedisPool jedisPool = (JedisPool) req.getServletContext().getAttribute("jedisPool");

      if (jedisPool == null) {
        throw new SocketException("Error connecting to Jedis pool");
      }
      Long visits;

      try (Jedis jedis = jedisPool.getResource()) {
        visits = jedis.incr("visits");
      }

      resp.setStatus(HttpServletResponse.SC_OK);
      resp.getWriter().println("Visitor counter: " + String.valueOf(visits));
    } catch (Exception e) {
      resp.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
    }
  }
}

Node.js

此应用使用 redis 模块。

{
  "name": "memorystore-redis",
  "description": "An example of using Memorystore(Redis) with Node.js",
  "version": "0.0.1",
  "private": true,
  "license": "Apache Version 2.0",
  "author": "Google Inc.",
  "engines": {
    "node": ">=16.0.0"
  },
  "dependencies": {
    "redis": "^4.0.0"
  }
}

'use strict';
const http = require('http');
const redis = require('redis');

const REDISHOST = process.env.REDISHOST || 'localhost';
const REDISPORT = process.env.REDISPORT || 6379;

const client = redis.createClient(REDISPORT, REDISHOST);
client.on('error', err => console.error('ERR:REDIS:', err));

// create a server
http
  .createServer((req, res) => {
    // increment the visit counter
    client.incr('visits', (err, reply) => {
      if (err) {
        console.log(err);
        res.status(500).send(err.message);
        return;
      }
      res.writeHead(200, {'Content-Type': 'text/plain'});
      res.end(`Visitor number: ${reply}\n`);
    });
  })
  .listen(8080);

Python

此应用使用 Flask 进行网络服务，并使用 redis-py 软件包与 Redis 实例进行通信。

Flask==3.0.3
gunicorn==22.0.0
redis==5.0.1
Werkzeug==3.0.3

import logging
import os

from flask import Flask
import redis

app = Flask(__name__)

redis_host = os.environ.get("REDISHOST", "localhost")
redis_port = int(os.environ.get("REDISPORT", 6379))
redis_client = redis.StrictRedis(host=redis_host, port=redis_port)


@app.route("/")
def index():
    value = redis_client.incr("counter", 1)
    return f"Visitor number: {value}"


@app.errorhandler(500)
def server_error(e):
    logging.exception("An error occurred during a request.")
    return (
        """
    An internal error occurred: <pre>{}</pre>
    See logs for full stacktrace.
    """.format(
            e
        ),
        500,
    )


if __name__ == "__main__":
    # This is used when running locally. Gunicorn is used to run the
    # application on Google App Engine and Cloud Run.
    # See entrypoint in app.yaml or Dockerfile.
    app.run(host="127.0.0.1", port=8080, debug=True)

将应用部署到 Compute Engine 虚拟机

导航到 gce_deployment 目录：

cd gce_deployment

部署脚本将软件工件上传到 Cloud Storage 路径。然后，该脚本启动一个 Compute Engine 实例，并创建防火墙来公开端口 8080。接着，启动脚本准备好实例。

设置 REDISHOST 和 REDISPORT 环境变量：

   export REDISHOST=[REDISHOST]
   export REDISPORT=[REDISPORT]

其中：

• REDISHOST 是托管式 Redis 实例 IP。
• REDISPORT 是托管的 Redis 实例端口，默认为 6379。

设置 GCS_BUCKET_NAME 环境变量：

     export GCS_BUCKET_NAME=[BUCKET_NAME]/[PATH]

其中：

• BUCKET_NAME 是 Cloud Storage 存储分区的名称。
• PATH 是要存储应用工件的目录的可选路径。

下面是一个示例部署脚本，它在新的 Compute Engine 虚拟机实例上部署此应用。

Go

if [ -z "$REDISHOST" ]; then
  echo "Must set \$REDISHOST. For example: REDISHOST=127.0.0.1"
  exit 1
fi

if [ -z "$REDISPORT" ]; then
  echo "Must set \$REDISPORT. For example: REDISPORT=6379"
  exit 1
fi

if [ -z "$GCS_BUCKET_NAME" ]; then
  echo "Must set \$GCS_BUCKET_NAME. For example: GCS_BUCKET_NAME=my-bucket"
  exit 1
fi

if [ -z "$ZONE" ]; then
  ZONE=$(gcloud config get-value compute/zone -q)
  echo "$ZONE"
fi


# Cross compile the app for linux/amd64
GOOS=linux GOARCH=amd64 go build -v -o app ../main.go
# Add the app binary
tar -cvf app.tar app
# Copy to GCS bucket
gsutil cp app.tar gs://"$GCS_BUCKET_NAME"/gce/

# Create an instance
gcloud compute instances create my-instance \
    --image-family=debian-9 \
    --image-project=debian-cloud \
    --machine-type=g1-small \
    --scopes cloud-platform \
    --metadata-from-file startup-script=startup-script.sh \
    --metadata gcs-bucket="$GCS_BUCKET_NAME",redis-host="$REDISHOST",redis-port="$REDISPORT" \
    --zone "$ZONE" \
    --tags http-server

gcloud compute firewall-rules create allow-http-server-8080 \
    --allow tcp:8080 \
    --source-ranges 0.0.0.0/0 \
    --target-tags http-server \
    --description "Allow port 8080 access to http-server"

Java

if [ -z "$GCS_BUCKET_NAME" ]; then
    echo "Must set \$GCS_BUCKET_NAME. For example: GCS_BUCKET_NAME=my-bucket"
    exit 1
fi

if [ -z "$ZONE" ]; then
  ZONE=$(gcloud config get-value compute/zone -q)
  echo $ZONE
fi

if [ -z "$WAR" ]; then
  WAR=visitcounter-1.0-SNAPSHOT.war
fi

#Build the WAR package
cd ..
mvn clean package

#Copy the WAR artifact to the GCS bucket location
gsutil cp -r target/${WAR} gs://"$GCS_BUCKET_NAME"/gce/

cd gce_deployment

# Create an instance
gcloud compute instances create my-instance \
    --image-family=debian-9 \
    --image-project=debian-cloud \
    --machine-type=g1-small \
    --scopes cloud-platform \
    --metadata-from-file startup-script=startup-script.sh \
    --metadata gcs-bucket=$GCS_BUCKET_NAME,app-war=$WAR \
    --zone $ZONE \
    --tags http-server

gcloud compute firewall-rules create allow-http-server-8080 \
    --allow tcp:8080 \
    --source-ranges 0.0.0.0/0 \
    --target-tags http-server \
    --description "Allow port 8080 access to http-server"

Node.js

if [ -z "$REDISHOST" ]; then
  echo "Must set \$REDISHOST. For example: REDISHOST=127.0.0.1"
  exit 1
fi

if [ -z "$REDISPORT" ]; then
  echo "Must set \$REDISPORT. For example: REDISPORT=6379"
  exit 1
fi

if [ -z "$GCS_BUCKET_NAME" ]; then
  echo "Must set \$GCS_BUCKET_NAME. For example: GCS_BUCKET_NAME=my-bucket"
  exit 1
fi

if [ -z "$ZONE" ]; then
  ZONE=$(gcloud config get-value compute/zone -q)
  echo $ZONE
fi

#Upload the tar to GCS
tar -cvf app.tar -C .. package.json server.js
gsutil cp app.tar gs://"$GCS_BUCKET_NAME"/gce/

# Create an instance
gcloud compute instances create my-instance \
    --image-family=debian-9 \
    --image-project=debian-cloud \
    --machine-type=g1-small \
    --scopes cloud-platform \
    --metadata-from-file startup-script=startup-script.sh \
    --metadata gcs-bucket=$GCS_BUCKET_NAME,redis-host=$REDISHOST,redis-port=$REDISPORT \
    --zone $ZONE \
    --tags http-server

gcloud compute firewall-rules create allow-http-server-8080 \
    --allow tcp:8080 \
    --source-ranges 0.0.0.0/0 \
    --target-tags http-server \
    --description "Allow port 8080 access to http-server"

Python

if [ -z "$REDISHOST" ]; then
  echo "Must set \$REDISHOST. For example: REDISHOST=127.0.0.1"
  exit 1
fi

if [ -z "$REDISPORT" ]; then
  echo "Must set \$REDISPORT. For example: REDISPORT=6379"
  exit 1
fi

if [ -z "$GCS_BUCKET_NAME" ]; then
  echo "Must set \$GCS_BUCKET_NAME. For example: GCS_BUCKET_NAME=my-bucket"
  exit 1
fi

if [ -z "$ZONE" ]; then
  ZONE=$(gcloud config get-value compute/zone -q)
  echo $ZONE
fi

#Upload the tar to GCS
tar -cvf app.tar -C .. requirements.txt main.py
# Copy to GCS bucket
gsutil cp app.tar gs://"$GCS_BUCKET_NAME"/gce/

# Create an instance
gcloud compute instances create my-instance \
    --image-family=debian-11 \
    --image-project=debian-cloud \
    --machine-type=g1-small \
    --scopes cloud-platform \
    --metadata-from-file startup-script=startup-script.sh \
    --metadata gcs-bucket=$GCS_BUCKET_NAME,redis-host=$REDISHOST,redis-port=$REDISPORT \
    --zone $ZONE \
    --tags http-server

gcloud compute firewall-rules create allow-http-server-8080 \
    --allow tcp:8080 \
    --source-ranges 0.0.0.0/0 \
    --target-tags http-server \
    --description "Allow port 8080 access to http-server"

运行部署脚本：

     chmod +x deploy.sh
     ./deploy.sh

应用启动脚本

示例部署脚本中使用此启动脚本来准备实例。要详细了解启动脚本以及如何查看启动脚本执行日志，请参阅运行启动脚本。

Go

set -ex

# Talk to the metadata server to get the project id and location of application binary.
PROJECTID=$(curl -s "http://metadata.google.internal/computeMetadata/v1/project/project-id" -H "Metadata-Flavor: Google")
export PROJECTID
GCS_BUCKET_NAME=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/gcs-bucket" -H "Metadata-Flavor: Google")
REDISHOST=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-host" -H "Metadata-Flavor: Google")
REDISPORT=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-port" -H "Metadata-Flavor: Google")

# Install dependencies from apt
apt-get update
apt-get install -yq ca-certificates supervisor

# Install logging monitor. The monitor will automatically pickup logs send to
# syslog.
curl "https://storage.googleapis.com/signals-agents/logging/google-fluentd-install.sh" --output google-fluentd-install.sh
checksum=$(sha256sum google-fluentd-install.sh | awk '{print $1;}')
if [ "$checksum" != "ec78e9067f45f6653a6749cf922dbc9d79f80027d098c90da02f71532b5cc967" ]; then
    echo "Checksum does not match"
    exit 1
fi
chmod +x google-fluentd-install.sh && ./google-fluentd-install.sh
service google-fluentd restart &

gsutil cp gs://"$GCS_BUCKET_NAME"/gce/app.tar /app.tar
mkdir -p /app
tar -x -f /app.tar -C /app
chmod +x /app/app

# Create a goapp user. The application will run as this user.
getent passwd goapp || useradd -m -d /home/goapp goapp
chown -R goapp:goapp /app

# Configure supervisor to run the Go app.
cat >/etc/supervisor/conf.d/goapp.conf << EOF
[program:goapp]
directory=/app
environment=HOME="/home/goapp",USER="goapp",REDISHOST=$REDISHOST,REDISPORT=$REDISPORT
command=/app/app
autostart=true
autorestart=true
user=goapp
stdout_logfile=syslog
stderr_logfile=syslog
EOF

supervisorctl reread
supervisorctl update

Java

set -ex

# Talk to the metadata server to get the project id and location of application binary.
PROJECTID=$(curl -s "http://metadata.google.internal/computeMetadata/v1/project/project-id" -H "Metadata-Flavor: Google")
GCS_BUCKET_NAME=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/gcs-bucket" -H "Metadata-Flavor: Google")
WAR=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/app-war" -H "Metadata-Flavor: Google")

gsutil cp gs://"$GCS_BUCKET_NAME"/gce/"$WAR" .

# Install dependencies from apt
apt-get update
apt-get install -qq openjdk-8-jdk-headless

# Make Java8 the default
update-alternatives --set java /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java

# Jetty Setup
mkdir -p /opt/jetty/temp
mkdir -p /var/log/jetty

# Get Jetty
curl -L https://repo1.maven.org/maven2/org/eclipse/jetty/jetty-distribution/9.4.10.v20180503/jetty-distribution-9.4.10.v20180503.tar.gz -o jetty9.tgz
tar xf jetty9.tgz  --strip-components=1 -C /opt/jetty

# Add a Jetty User
useradd --user-group --shell /bin/false --home-dir /opt/jetty/temp jetty

cd /opt/jetty
# Add running as "jetty"
java -jar /opt/jetty/start.jar --add-to-startd=setuid
cd /

# very important - by renaming the war to root.war, it will run as the root servlet.
mv $WAR /opt/jetty/webapps/root.war

# Make sure "jetty" owns everything.
chown --recursive jetty /opt/jetty

# Configure the default paths for the Jetty service
cp /opt/jetty/bin/jetty.sh /etc/init.d/jetty
echo "JETTY_HOME=/opt/jetty" > /etc/default/jetty
{
  echo "JETTY_BASE=/opt/jetty"
  echo "TMPDIR=/opt/jetty/temp"
  echo "JAVA_OPTIONS=-Djetty.http.port=8080"
  echo "JETTY_LOGS=/var/log/jetty"
} >> /etc/default/jetty


# Reload daemon to pick up new service
systemctl daemon-reload

# Install logging monitor. The monitor will automatically pickup logs sent to syslog.
curl -s "https://storage.googleapis.com/signals-agents/logging/google-fluentd-install.sh" | bash
service google-fluentd restart &

service jetty start
service jetty check

echo "Startup Complete"

Node.js

set -ex

# Talk to the metadata server to get the project id and location of application binary.
PROJECTID=$(curl -s "http://metadata.google.internal/computeMetadata/v1/project/project-id" -H "Metadata-Flavor: Google")
GCS_BUCKET_NAME=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/gcs-bucket" -H "Metadata-Flavor: Google")
REDISHOST=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-host" -H "Metadata-Flavor: Google")
REDISPORT=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-port" -H "Metadata-Flavor: Google")

# Install dependencies from apt
apt-get update
# Install Node.js 9
curl -sL https://deb.nodesource.com/setup_9.x | sudo -E bash -
apt-get install -yq ca-certificates supervisor nodejs build-essential


# Install logging monitor. The monitor will automatically pickup logs send to
# syslog.
curl -s "https://storage.googleapis.com/signals-agents/logging/google-fluentd-install.sh" | bash
service google-fluentd restart &

gsutil cp gs://"$GCS_BUCKET_NAME"/gce/app.tar /app.tar
mkdir -p /app
tar -x -f /app.tar -C /app
cd /app
# Install the app dependencies
npm install

# Create a nodeapp user. The application will run as this user.
getent passwd nodeapp || useradd -m -d /home/nodeapp nodeapp
chown -R nodeapp:nodeapp /app

# Configure supervisor to run the Go app.
cat >/etc/supervisor/conf.d/nodeapp.conf << EOF
[program:nodeapp]
directory=/app
environment=HOME="/home/nodeapp",USER="nodeapp",REDISHOST=$REDISHOST,REDISPORT=$REDISPORT
command=node server.js
autostart=true
autorestart=true
user=nodeapp
stdout_logfile=syslog
stderr_logfile=syslog
EOF

supervisorctl reread
supervisorctl update

Python

set -v

# Talk to the metadata server to get the project id and location of application binary.
PROJECTID=$(curl -s "http://metadata.google.internal/computeMetadata/v1/project/project-id" -H "Metadata-Flavor: Google")
GCS_BUCKET_NAME=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/gcs-bucket" -H "Metadata-Flavor: Google")
REDISHOST=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-host" -H "Metadata-Flavor: Google")
REDISPORT=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/redis-port" -H "Metadata-Flavor: Google")

# Install dependencies from apt
apt-get update
apt-get install -yq \
    git build-essential supervisor python python-dev python-pip libffi-dev \
    libssl-dev

# Install logging monitor. The monitor will automatically pickup logs send to
# syslog.
curl -s "https://storage.googleapis.com/signals-agents/logging/google-fluentd-install.sh" | bash
service google-fluentd restart &

gsutil cp gs://"$GCS_BUCKET_NAME"/gce/app.tar /app.tar
mkdir -p /app
tar -x -f /app.tar -C /app
cd /app

# Install the app dependencies
pip install --upgrade pip virtualenv
virtualenv /app/env
/app/env/bin/pip install -r /app/requirements.txt

# Create a pythonapp user. The application will run as this user.
getent passwd pythonapp || useradd -m -d /home/pythonapp pythonapp
chown -R pythonapp:pythonapp /app

# Configure supervisor to run the app.
cat >/etc/supervisor/conf.d/pythonapp.conf << EOF
[program:pythonapp]
directory=/app
environment=HOME="/home/pythonapp",USER="pythonapp",REDISHOST=$REDISHOST,REDISPORT=$REDISPORT
command=/app/env/bin/gunicorn main:app --bind 0.0.0:8080
autostart=true
autorestart=true
user=pythonapp
stdout_logfile=syslog
stderr_logfile=syslog
EOF

supervisorctl reread
supervisorctl update

可能需要几分钟才能在新建的 Compute Engine 实例上完成示例应用的部署。

实例就绪且启动脚本执行完毕后，请转到 Compute Engine 实例页面并复制外部 IP 地址。

要查看所部署的示例应用，请访问 http://[EXTERNAL-IP]:8080

您可以使用 teardown.sh 脚本删除由部署脚本创建的实例和防火墙：

gcloud compute instances delete my-instance

gcloud compute firewall-rules delete allow-http-server-8080