spark源码解析：2.2 start-daemon.sh脚本分析

分手后的思念是犯贱 2023-06-11 12:27 107阅读 0赞

> 上节解析了start-master.sh脚本的内容并进行了debug：[start-master.sh脚本解析][start-master.sh]，这节分析spark-daemon.sh脚本的内容并进行debug

## 1. spark-daemon.sh脚本内容 ##

usage="Usage: spark-daemon.sh [--config <conf-dir>] (start|stop|submit|status) <spark-command> <spark-instance-number> <args...>"
    
    # 如果没有提供参数，则打印usage使用说明并中断脚本
    if [ $# -le 1 ]; then
      echo $usage
      exit 1
    fi
    
    # 判断是否配置了SPARK_HOME，如果没有则手动设置
    if [ -z "${SPARK_HOME}" ]; then
      export SPARK_HOME="$(cd "`dirname "$0"`"/..; pwd)"
    fi
    
    # 通过.加上文件名临时执行spark-config.sh脚本
    ## 设置SPARK_HOME、SPARK_CONF_DIR以及python的一些环境变量
    . "${SPARK_HOME}/sbin/spark-config.sh"
    
    # 检查参数中是否包含--config，如果该参数的值不为目录则退出
    if [ "$1" == "--config" ]
    then
      # 移除第一个参数
      shift
      conf_dir="$1"
      if [ ! -d "$conf_dir" ]
      then
        echo "ERROR : $conf_dir is not a directory"
        echo $usage
        exit 1
      else
        export SPARK_CONF_DIR="$conf_dir"
      fi
      shift
    fi
    
    # 分别对option、command、instance进行赋值
    option=$1
    shift
    command=$1
    shift
    instance=$1
    shift
    
    spark_rotate_log ()
    {
        log=$1;
        num=5;
        if [ -n "$2" ]; then
    	num=$2
        fi
        if [ -f "$log" ]; then # rotate logs
    	while [ $num -gt 1 ]; do
    	    prev=`expr $num - 1`
    	    [ -f "$log.$prev" ] && mv "$log.$prev" "$log.$num"
    	    num=$prev
    	done
    	mv "$log" "$log.$num";
        fi
    }
    
    
    # 通过.加上文件名临时执行load-spark-env.sh脚本
    ## 设置SPARK_HOME、SPARK_SCALA_VERSION环境变量
    
    . "${SPARK_HOME}/bin/load-spark-env.sh"
    
    if [ "$SPARK_IDENT_STRING" = "" ]; then
      export SPARK_IDENT_STRING="$USER"
    fi
    
    # 设置SPARK_PRINT_LAUNCH_COMMAND环境变量
    export SPARK_PRINT_LAUNCH_COMMAND="1"
    
    # 日志相关
    if [ "$SPARK_LOG_DIR" = "" ]; then
      export SPARK_LOG_DIR="${SPARK_HOME}/logs"
    fi
    mkdir -p "$SPARK_LOG_DIR"
    touch "$SPARK_LOG_DIR"/.spark_test > /dev/null 2>&1
    TEST_LOG_DIR=$?
    if [ "${TEST_LOG_DIR}" = "0" ]; then
      rm -f "$SPARK_LOG_DIR"/.spark_test
    else
      chown "$SPARK_IDENT_STRING" "$SPARK_LOG_DIR"
    fi
    
    # 设置spark进程目录
    if [ "$SPARK_PID_DIR" = "" ]; then
      SPARK_PID_DIR=/tmp
    fi
    
    # 定义log和pid变量
    log="$SPARK_LOG_DIR/spark-$SPARK_IDENT_STRING-$command-$instance-$HOSTNAME.out"
    pid="$SPARK_PID_DIR/spark-$SPARK_IDENT_STRING-$command-$instance.pid"
    
    # 设置默认的调度优先级
    if [ "$SPARK_NICENESS" = "" ]; then
        export SPARK_NICENESS=0
    fi
    
    # 该方法
    execute_command() {
      # 看不懂+set是啥意思...不过debug的时候会进这个条件判断
      if [ -z ${SPARK_NO_DAEMONIZE+set} ]; then
          # 后台执行脚本命令，此处是获取传入该方法的所有参数，进行运行
          nohup -- "$@" >> $log 2>&1 < /dev/null &
          # 获取最新的后台运行的pid，即上条命令所占用的pid
          newpid="$!"
    		
          echo "$newpid" > "$pid"
    
          # 共等待5秒来等待上述程序的运行
          for i in {1..10}
          do
            if [[ $(ps -p "$newpid" -o comm=) =~ "java" ]]; then
               break
            fi
            sleep 0.5
          done
          
          # 再等待2秒
          sleep 2
          # 当程序正常运行时，打印日志
          if [[ ! $(ps -p "$newpid" -o comm=) =~ "java" ]]; then
            echo "failed to launch: $@"
            tail -2 "$log" | sed 's/^/  /'
            echo "full log in $log"
          fi
      else
          "$@"
      fi
    }
    
    # 该方法主要判断是否能继续进行，并做一些预处理
    run_command() {
      # 获取第一个参数赋值给mode
      mode="$1"
      shift
      # 创建进程目录
      mkdir -p "$SPARK_PID_DIR"
      
      # 判断进程文件是否存在，如果存在则给出提示：进程已存在，请先停止
      if [ -f "$pid" ]; then
        TARGET_ID="$(cat "$pid")"
        if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
          echo "$command running as process $TARGET_ID.  Stop it first."
          exit 1
        fi
      fi
      # 如果spark_master不为空，则在masters(master高可用的情况)中同步删除部分文件
      if [ "$SPARK_MASTER" != "" ]; then
        echo rsync from "$SPARK_MASTER"
        rsync -a -e ssh --delete --exclude=.svn --exclude='logs/*' --exclude='contrib/hod/logs/*' "$SPARK_MASTER/" "${SPARK_HOME}"
      fi
    
      spark_rotate_log "$log"
      echo "starting $command, logging to $log"
    
      # 使用mode变量进行匹配
      case "$mode" in
        (class)
          # 当变量为class时调用execute_command，传入参数
          execute_command nice -n "$SPARK_NICENESS" "${SPARK_HOME}"/bin/spark-class "$command" "$@"
          ;;
    
        (submit)
          # 当变量为submit时调用execute_command，传入参数
          execute_command nice -n "$SPARK_NICENESS" bash "${SPARK_HOME}"/bin/spark-submit --class "$command" "$@"
          ;;
    
        (*)
          echo "unknown mode: $mode"
          exit 1
          ;;
      esac
    
    }
    
    # 使用option变量进行匹配
    case $option in
      # 如果变量为submit则执行run_command方法，并将submit作为第一个参数传入
      (submit)
        run_command submit "$@"
        ;;
      # 如果变量为start则执行run_command方法，并将start作为第一个参数传入
      (start)
        run_command class "$@"
        ;;
      # 如果变量为stop，则执行kill命令，并删除进程文件	
      (stop)
    
        if [ -f $pid ]; then
          TARGET_ID="$(cat "$pid")"
          if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
            echo "stopping $command"
            kill "$TARGET_ID" && rm -f "$pid"
          else
            echo "no $command to stop"
          fi
        else
          echo "no $command to stop"
        fi
        ;;
      # 如果变量为status，则打印状态信息
      (status)
    
        if [ -f $pid ]; then
          TARGET_ID="$(cat "$pid")"
          if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
            echo $command is running.
            exit 0
          else
            echo $pid file is present but $command not running
            exit 1
          fi
        else
          echo $command not running.
          exit 2
        fi
        ;;
      # 如果变量未匹配上上述情况，则打印脚本使用方法
      (*)
        echo $usage
        exit 1
        ;;
    
    esac

## 2. debug spark-daemon.sh脚本 ##

因为start-master.sh脚本**内部调用了spark-daemon.sh脚本**，并传入了参数，所以可以通过外部传入参数并进行debug

> sh -x /usr/local/spark/sbin/spark-daemon.sh start org.apache.spark.deploy.master.Master 1 --host s101 --port 7077 --webui-port 8080

+ usage='Usage: spark-daemon.sh [--config <conf-dir>] (start|stop|submit|status) <spark-command> <spark-instance-number> <args...>'
    
    # 如果没有提供参数，则打印usage使用说明并中断脚本
    + '[' 9 -le 1 ']'
    
    # 判断是否配置了SPARK_HOME，如果没有则手动设置
    + '[' -z /usr/local/spark ']'
    
    # 通过.加上文件名临时执行spark-config.sh脚本
    ## 设置SPARK_HOME、SPARK_CONF_DIR以及python的一些环境变量
    + . /usr/local/spark/sbin/spark-config.sh
    ++ '[' -z /usr/local/spark ']'
    ++ export SPARK_CONF_DIR=/usr/local/spark/conf
    ++ SPARK_CONF_DIR=/usr/local/spark/conf
    ++ '[' -z '' ']'
    ++ export PYTHONPATH=/usr/local/spark/python:
    ++ PYTHONPATH=/usr/local/spark/python:
    ++ export PYTHONPATH=/usr/local/spark/python/lib/py4j-0.10.7-src.zip:/usr/local/spark/python:
    ++ PYTHONPATH=/usr/local/spark/python/lib/py4j-0.10.7-src.zip:/usr/local/spark/python:
    ++ export PYSPARK_PYTHONPATH_SET=1
    ++ PYSPARK_PYTHONPATH_SET=1
    
    # 检查参数中是否包含--config，如果该参数的值不为目录则退出
    + '[' start == --config ']'
    
    
    # 分别对option、command、instance进行赋值
    + option=start
    + shift
    + command=org.apache.spark.deploy.master.Master
    + shift
    + instance=1
    + shift
    
    # 通过.加上文件名临时执行load-spark-env.sh脚本
    ## 设置SPARK_HOME、SPARK_SCALA_VERSION环境变量
    + . /usr/local/spark/bin/load-spark-env.sh
    ++ '[' -z /usr/local/spark ']'
    ++ '[' -z '' ']'
    ++ export SPARK_ENV_LOADED=1
    ++ SPARK_ENV_LOADED=1
    ++ export SPARK_CONF_DIR=/usr/local/spark/conf
    ++ SPARK_CONF_DIR=/usr/local/spark/conf
    ++ '[' -f /usr/local/spark/conf/spark-env.sh ']'
    ++ set -a
    ++ . /usr/local/spark/conf/spark-env.sh
    +++ JAVA_HOME=/usr/local/jdk
    +++ HADOOP_CONF_DIR=/usr/local/spark/hadoop/etc/hadoop
    +++ SPARK_LOCAL_IP=s101
    ++ set +a
    ++ '[' -z '' ']'
    ++ ASSEMBLY_DIR2=/usr/local/spark/assembly/target/scala-2.11
    ++ ASSEMBLY_DIR1=/usr/local/spark/assembly/target/scala-2.12
    ++ [[ -d /usr/local/spark/assembly/target/scala-2.11 ]]
    ++ '[' -d /usr/local/spark/assembly/target/scala-2.11 ']'
    ++ export SPARK_SCALA_VERSION=2.12
    ++ SPARK_SCALA_VERSION=2.12
    
    + '[' '' = '' ']'
    + export SPARK_IDENT_STRING=hadoop
    + SPARK_IDENT_STRING=hadoop
    
    # 设置SPARK_PRINT_LAUNCH_COMMAND环境变量
    + export SPARK_PRINT_LAUNCH_COMMAND=1
    + SPARK_PRINT_LAUNCH_COMMAND=1
    
    # 日志相关
    + '[' '' = '' ']'
    + export SPARK_LOG_DIR=/usr/local/spark/logs
    + SPARK_LOG_DIR=/usr/local/spark/logs
    + mkdir -p /usr/local/spark/logs
    + touch /usr/local/spark/logs/.spark_test
    + TEST_LOG_DIR=0
    + '[' 0 = 0 ']'
    + rm -f /usr/local/spark/logs/.spark_test
    + '[' '' = '' ']'
    
    # 设置spark进程目录
    + SPARK_PID_DIR=/tmp
    
    
    # 定义log和pid变量
    + log=/usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out
    + pid=/tmp/spark-hadoop-org.apache.spark.deploy.master.Master-1.pid
    
    # 设置默认的调度优先级
    + '[' '' = '' ']'
    + export SPARK_NICENESS=0
    + SPARK_NICENESS=0
    
    
    # 使用option参数进行匹配，调用方法，传入不同的参数
    + case $option in
    # 调用run_command方法，传入class参数以及上个脚本传入的参数
    + run_command class --host s101 --port 7077 --webui-port 8080
    
    
    # run_command方法内容
    + mode=class
    + shift
    # 创建进程目录
    + mkdir -p /tmp
    # 判断进程文件是否存在，如果存在则给出提示：进程已存在，请先停止
    + '[' -f /tmp/spark-hadoop-org.apache.spark.deploy.master.Master-1.pid ']'
    + '[' '' '!=' '' ']'
    + spark_rotate_log /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out
    + log=/usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out
    + num=5
    + '[' -n '' ']'
    + '[' -f /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out ']'
    + '[' 5 -gt 1 ']'
    ++ expr 5 - 1
    + prev=4
    + '[' -f /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.4 ']'
    + mv /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.4 /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.5
    + num=4
    + '[' 4 -gt 1 ']'
    ++ expr 4 - 1
    + prev=3
    + '[' -f /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.3 ']'
    + mv /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.3 /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.4
    + num=3
    + '[' 3 -gt 1 ']'
    ++ expr 3 - 1
    + prev=2
    + '[' -f /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.2 ']'
    + mv /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.2 /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.3
    + num=2
    + '[' 2 -gt 1 ']'
    ++ expr 2 - 1
    + prev=1
    + '[' -f /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.1 ']'
    + mv /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.1 /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.2
    + num=1
    + '[' 1 -gt 1 ']'
    + mv /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out.1
    + echo 'starting org.apache.spark.deploy.master.Master, logging to /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out'
    starting org.apache.spark.deploy.master.Master, logging to /usr/local/spark/logs/spark-hadoop-org.apache.spark.deploy.master.Master-1-s101.out
    
    # 使用mode值:class进行匹配
    + case "$mode" in
    # 调用execute_command方法
    + execute_command nice -n 0 /usr/local/spark/bin/spark-class org.apache.spark.deploy.master.Master --host s101 --port 7077 --webui-port 8080
    
    #execute_command方法内容
    + '[' -z ']'
    + newpid=3150
    + echo 3150
    + for i in '{1..10}'
    ++ ps -p 3150 -o comm=
    
    # 调用spark-class脚本
    + nohup -- nice -n 0 /usr/local/spark/bin/spark-class org.apache.spark.deploy.master.Master --host s101 --port 7077 --webui-port 8080
    + [[ bash =~ java ]]
    + sleep 0.5
    + for i in '{1..10}'
    ++ ps -p 3150 -o comm=
    + [[ java =~ java ]]
    + break
    + sleep 2
    ++ ps -p 3150 -o comm=
    + [[ ! java =~ java ]]

[start-master.sh]: https://blog.csdn.net/hlp4207/article/details/102824248