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fabric bootstrap.sh 安裝腳本分析

2021-10-17 09:50:05 區塊鏈

為什么要分析安裝腳本

對于初學者，很多檔案都是直接運行該安裝腳本，就可以自動化部署Fabric程式，雖然表面上針對小白比較友好，不需要自己下載原始碼進行編譯，但是很多資源都是國外的，下載速度緩慢我也是飽受折磨，下面分析一下安裝腳本，有助于我們更加深入理解Fabric架構，同時分析安裝邏輯，修改腳本方便部署，

安裝腳本在哪里

我們以fabric1.4.8為例進行分析，相關github上面的鏈接如下，我們發現官方腳本不好用，下載非常緩慢，
https://github.com/hyperledger/fabric/blob/v1.4.8/scripts/bootstrap.sh

安裝邏輯是什么

下面是安裝腳本的基本邏輯框架代碼，接下來我們一點點分析，

#!/bin/bash
#
# Copyright IBM Corp. All Rights Reserved.
#
# SPDX-License-Identifier: Apache-2.0
#
# if version not passed in, default to latest released version
export VERSION=1.4.8
# if ca version not passed in, default to latest released version
export CA_VERSION=1.4.7
# current version of thirdparty images (couchdb, kafka and zookeeper) released
export THIRDPARTY_IMAGE_VERSION=0.4.21
export ARCH=$(echo "$(uname -s|tr '[:upper:]' '[:lower:]'|sed 's/mingw64_nt.*/windows/')-$(uname -m | sed 's/x86_64/amd64/g')")
export MARCH=$(uname -m)

printHelp() {
}

dockerFabricPull() {
}

dockerThirdPartyImagesPull() {
}

dockerCaPull() {
}

samplesInstall() {
}

# Incrementally downloads the .tar.gz file locally first, only decompressing it
# after the download is complete. This is slower than binaryDownload() but
# allows the download to be resumed.
binaryIncrementalDownload() {
}

# This will attempt to download the .tar.gz all at once, but will trigger the
# binaryIncrementalDownload() function upon a failure, allowing for resume
# if there are network failures.
binaryDownload() {
}

dockerInstall() {
}

DOCKER=true
SAMPLES=true
BINARIES=true

# Parse commandline args pull out
# version and/or ca-version strings first
if [ ! -z "$1" -a ${1:0:1} != "-" ]; then
  VERSION=$1;shift
  if [ ! -z "$1"  -a ${1:0:1} != "-" ]; then
    CA_VERSION=$1;shift
    if [ ! -z "$1"  -a ${1:0:1} != "-" ]; then
      THIRDPARTY_IMAGE_VERSION=$1;shift
    fi
  fi
fi

# prior to 1.2.0 architecture was determined by uname -m
if [[ $VERSION =~ ^1\.[0-1]\.* ]]; then
  export FABRIC_TAG=${MARCH}-${VERSION}
  export CA_TAG=${MARCH}-${CA_VERSION}
  export THIRDPARTY_TAG=${MARCH}-${THIRDPARTY_IMAGE_VERSION}
else
  # starting with 1.2.0, multi-arch images will be default
  : ${CA_TAG:="$CA_VERSION"}
  : ${FABRIC_TAG:="$VERSION"}
  : ${THIRDPARTY_TAG:="$THIRDPARTY_IMAGE_VERSION"}
fi

BINARY_FILE=hyperledger-fabric-${ARCH}-${VERSION}.tar.gz
CA_BINARY_FILE=hyperledger-fabric-ca-${ARCH}-${CA_VERSION}.tar.gz

# then parse opts
while getopts "h?dsb" opt; do
  case "$opt" in
    h|\?)
      printHelp
      exit 0
    ;;
    d)  DOCKER=false
    ;;
    s)  SAMPLES=false
    ;;
    b)  BINARIES=false
    ;;
  esac
done

if [ "$SAMPLES" == "true" ]; then
  echo
  echo "Installing hyperledger/fabric-samples repo"
  echo
  samplesInstall
fi
if [ "$BINARIES" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric binaries"
  echo
  binariesInstall
fi
if [ "$DOCKER" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric docker images"
  echo
  dockerInstall
fi

和傳統編程語言一樣，此腳本首先定義了一下全域變數，同時通過if判斷邏輯，執行先關函式，進行環境的部署，先關原始碼的下載，

逐一進行分析

首先看的肯定是幫助命令，

printHelp() {
  echo "Usage: bootstrap.sh [version [ca_version [thirdparty_version]]] [options]"
  echo
  echo "options:"
  echo "-h : this help"
  echo "-d : bypass docker image download"
  echo "-s : bypass fabric-samples repo clone"
  echo "-b : bypass download of platform-specific binaries"
  echo
  echo "e.g. bootstrap.sh 1.4.8 -s"
  echo "would download docker images and binaries for version 1.4.8"
}

我們可以看出，此腳本主要執行三部分功能，第一下載docker鏡像，第二下載fabric-samples官方案例（為了更加方便的了解fabric構建專案），第三下載平臺二進制檔案，并且可以指定下載的版本，例如：1.4.8，同時可以引數選擇不下載那一部分，代碼最前面匯入了相關變數export VERSION=1.4.8、export CA_VERSION=1.4.7、export THIRDPARTY_IMAGE_VERSION=0.4.21，默認使用的是這些引數，

首先是邏輯框架

前面默認給出的變數值都是true，通過判斷引數值，執行相關功能，samplesInstall、binariesInstall，dockerInstall

if [ "$SAMPLES" == "true" ]; then
  echo
  echo "Installing hyperledger/fabric-samples repo"
  echo
  samplesInstall
fi
if [ "$BINARIES" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric binaries"
  echo
  binariesInstall
fi
if [ "$DOCKER" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric docker images"
  echo
  dockerInstall
fi

dockerInstall

我們可以看到下載docker鏡像，主要執行dockerFabricPull ${FABRIC_TAG} dockerCaPull ${CA_TAG} dockerThirdPartyImagesPull ${THIRDPARTY_TAG}源檔案無需更改，就可以執行，

這部分我們可以配置正確的docker國內加速源進行加速，不做過多的介紹，

dockerInstall() {
  which docker >& /dev/null
  NODOCKER=$?
  if [ "${NODOCKER}" == 0 ]; then
	  echo "===> Pulling fabric Images"
	  dockerFabricPull ${FABRIC_TAG}
	  echo "===> Pulling fabric ca Image"
	  dockerCaPull ${CA_TAG}
	  echo "===> Pulling thirdparty docker images"
	  dockerThirdPartyImagesPull ${THIRDPARTY_TAG}
	  echo
	  echo "===> List out hyperledger docker images"
	  docker images | grep hyperledger*
  else
    echo "========================================================="
    echo "Docker not installed, bypassing download of Fabric images"
    echo "========================================================="
  fi
}

dockerFabricPull() {
  local FABRIC_TAG=$1
  for IMAGES in peer orderer ccenv javaenv tools; do
      echo "==> FABRIC IMAGE: $IMAGES"
      echo
      docker pull hyperledger/fabric-$IMAGES:$FABRIC_TAG
      docker tag hyperledger/fabric-$IMAGES:$FABRIC_TAG hyperledger/fabric-$IMAGES
  done
}
dockerCaPull() {
      local CA_TAG=$1
      echo "==> FABRIC CA IMAGE"
      echo
      docker pull hyperledger/fabric-ca:$CA_TAG
      docker tag hyperledger/fabric-ca:$CA_TAG hyperledger/fabric-ca
}
dockerThirdPartyImagesPull() {
  local THIRDPARTY_TAG=$1
  for IMAGES in couchdb kafka zookeeper; do
      echo "==> THIRDPARTY DOCKER IMAGE: $IMAGES"
      echo
      docker pull hyperledger/fabric-$IMAGES:$THIRDPARTY_TAG
      docker tag hyperledger/fabric-$IMAGES:$THIRDPARTY_TAG hyperledger/fabric-$IMAGES
  done
}

binariesInstall

這里面需要修改的地方是binaryDownload函式，可以看出官方給出的下載鏈接為國外地址并且已經不在維護，也就是執行此腳本最緩慢的原因之一，https://nexus.hyperledger.org/content/repositories/releases/org/hyperledger/fabric/hyperledger-fabric/ A R C H ? {ARCH}- ARCH?{VERSION}/${BINARY_FILE}

此鏈接已經不在維護，所以要更換，如果想更快，使用https://hub.fastgit.org 加速github網站，進行下載

binariesInstall() {
  echo "===> Downloading version ${FABRIC_TAG} platform specific fabric binaries"
  # wget https://hub.fastgit.org/hyperledger/fabric/releases/download/v1.4.8/hyperledger-fabric-linux-amd64-1.4.8.tar.gz
  binaryDownload ${BINARY_FILE} https://hub.fastgit.org/hyperledger/fabric/releases/download/v${VERSION}/${BINARY_FILE}
  if [ $? -eq 22 ]; then
     echo
     echo "------> ${FABRIC_TAG} platform specific fabric binary is not available to download <----"
     echo
   fi

  echo "===> Downloading version ${CA_TAG} platform specific fabric-ca-client binary"
  binaryDownload ${CA_BINARY_FILE} https://hub.fastgit.org/hyperledger/fabric-ca/releases/download/v${CA_VERSION}/${CA_BINARY_FILE}
  if [ $? -eq 22 ]; then
     echo
     echo "------> ${CA_TAG} fabric-ca-client binary is not available to download  (Available from 1.1.0-rc1) <----"
     echo
   fi
}

binaryDownload() {
      local BINARY_FILE=$1
      local URL=$2
      echo "===> Downloading: " ${URL}
      # Check if a previous failure occurred and the file was partially downloaded
      if [ -e ${BINARY_FILE} ]; then
          echo "==> Partial binary file found. Resuming download..."
          binaryIncrementalDownload ${BINARY_FILE} ${URL}
      else
          curl -L --retry 5 --retry-delay 3 ${URL} | tar xz || rc=$?
          if [ ! -z "$rc" ]; then
              echo "==> There was an error downloading the binary file. Switching to incremental download."
              echo "==> Downloading file..."
              binaryIncrementalDownload ${BINARY_FILE} ${URL}
	  else
	      echo "==> Done."
          fi
      fi
}

samplesInstall

更換國內源，使用碼云的鏡像，進行加速下載fabric-samples，

samplesInstall() {
  # clone (if needed) hyperledger/fabric-samples and checkout corresponding
  # version to the binaries and docker images to be downloaded
  if [ -d first-network ]; then
    # if we are in the fabric-samples repo, checkout corresponding version
    echo "===> Checking out v${VERSION} of hyperledger/fabric-samples"
    git checkout v${VERSION}
  elif [ -d fabric-samples ]; then
    # if fabric-samples repo already cloned and in current directory,
    # cd fabric-samples and checkout corresponding version
    echo "===> Checking out v${VERSION} of hyperledger/fabric-samples"
    cd fabric-samples && git checkout v${VERSION}
  else
    echo "===> Cloning hyperledger/fabric-samples repo and checkout v${VERSION}"
    # git clone -b master https://github.com/hyperledger/fabric-samples.git && cd fabric-samples && git checkout v${VERSION}
    git clone -b master https://gitee.com/hyperledger/fabric-samples.git && cd fabric-samples && git checkout v${VERSION}
  fi
}

將上面修改完成之后完整的bootstrap.sh代碼，

bootstrap.sh

通過替換和修改源，最終實作加速效果，如果不想了解上述程序，就直接復制粘貼下面代碼即可，

#!/bin/bash
#
# Copyright IBM Corp. All Rights Reserved.
#
# SPDX-License-Identifier: Apache-2.0
#

# if version not passed in, default to latest released version
export VERSION=1.4.8
# if ca version not passed in, default to latest released version
export CA_VERSION=1.4.7
# current version of thirdparty images (couchdb, kafka and zookeeper) released
export THIRDPARTY_IMAGE_VERSION=0.4.21
export ARCH=$(echo "$(uname -s|tr '[:upper:]' '[:lower:]'|sed 's/mingw64_nt.*/windows/')-$(uname -m | sed 's/x86_64/amd64/g')")
export MARCH=$(uname -m)

printHelp() {
  echo "Usage: bootstrap.sh [version [ca_version [thirdparty_version]]] [options]"
  echo
  echo "options:"
  echo "-h : this help"
  echo "-d : bypass docker image download"
  echo "-s : bypass fabric-samples repo clone"
  echo "-b : bypass download of platform-specific binaries"
  echo
  echo "e.g. bootstrap.sh 1.4.8 -s"
  echo "would download docker images and binaries for version 1.4.8"
}

dockerFabricPull() {
  local FABRIC_TAG=$1
  for IMAGES in peer orderer ccenv javaenv tools; do
      echo "==> FABRIC IMAGE: $IMAGES"
      echo
      docker pull hyperledger/fabric-$IMAGES:$FABRIC_TAG
      docker tag hyperledger/fabric-$IMAGES:$FABRIC_TAG hyperledger/fabric-$IMAGES
  done
}

dockerThirdPartyImagesPull() {
  local THIRDPARTY_TAG=$1
  for IMAGES in couchdb kafka zookeeper; do
      echo "==> THIRDPARTY DOCKER IMAGE: $IMAGES"
      echo
      docker pull hyperledger/fabric-$IMAGES:$THIRDPARTY_TAG
      docker tag hyperledger/fabric-$IMAGES:$THIRDPARTY_TAG hyperledger/fabric-$IMAGES
  done
}

dockerCaPull() {
      local CA_TAG=$1
      echo "==> FABRIC CA IMAGE"
      echo
      docker pull hyperledger/fabric-ca:$CA_TAG
      docker tag hyperledger/fabric-ca:$CA_TAG hyperledger/fabric-ca
}

samplesInstall() {
  # clone (if needed) hyperledger/fabric-samples and checkout corresponding
  # version to the binaries and docker images to be downloaded
  if [ -d first-network ]; then
    # if we are in the fabric-samples repo, checkout corresponding version
    echo "===> Checking out v${VERSION} of hyperledger/fabric-samples"
    git checkout v${VERSION}
  elif [ -d fabric-samples ]; then
    # if fabric-samples repo already cloned and in current directory,
    # cd fabric-samples and checkout corresponding version
    echo "===> Checking out v${VERSION} of hyperledger/fabric-samples"
    cd fabric-samples && git checkout v${VERSION}
  else
    echo "===> Cloning hyperledger/fabric-samples repo and checkout v${VERSION}"
    git clone -b master https://gitee.com/hyperledger/fabric-samples.git && cd fabric-samples && git checkout v${VERSION}
  fi
}

# Incrementally downloads the .tar.gz file locally first, only decompressing it
# after the download is complete. This is slower than binaryDownload() but
# allows the download to be resumed.
binaryIncrementalDownload() {
      local BINARY_FILE=$1
      local URL=$2
      curl -f -s -C - ${URL} -o ${BINARY_FILE} || rc=$?
      # Due to limitations in the current Nexus repo:
      # curl returns 33 when there's a resume attempt with no more bytes to download
      # curl returns 2 after finishing a resumed download
      # with -f curl returns 22 on a 404
      if [ "$rc" = 22 ]; then
	  # looks like the requested file doesn't actually exist so stop here
	  return 22
      fi
      if [ -z "$rc" ] || [ $rc -eq 33 ] || [ $rc -eq 2 ]; then
          # The checksum validates that RC 33 or 2 are not real failures
          echo "==> File downloaded. Verifying the md5sum..."
          localMd5sum=$(md5sum ${BINARY_FILE} | awk '{print $1}')
          remoteMd5sum=$(curl -s ${URL}.md5)
          if [ "$localMd5sum" == "$remoteMd5sum" ]; then
              echo "==> Extracting ${BINARY_FILE}..."
              tar xzf ./${BINARY_FILE} --overwrite
	      echo "==> Done."
              rm -f ${BINARY_FILE} ${BINARY_FILE}.md5
          else
              echo "Download failed: the local md5sum is different from the remote md5sum. Please try again."
              rm -f ${BINARY_FILE} ${BINARY_FILE}.md5
              exit 1
          fi
      else
          echo "Failure downloading binaries (curl RC=$rc). Please try again and the download will resume from where it stopped."
          exit 1
      fi
}

# This will attempt to download the .tar.gz all at once, but will trigger the
# binaryIncrementalDownload() function upon a failure, allowing for resume
# if there are network failures.
binaryDownload() {
      local BINARY_FILE=$1
      local URL=$2
      echo "===> Downloading: " ${URL}
      # Check if a previous failure occurred and the file was partially downloaded
      if [ -e ${BINARY_FILE} ]; then
          echo "==> Partial binary file found. Resuming download..."
          binaryIncrementalDownload ${BINARY_FILE} ${URL}
      else
          curl -L --retry 5 --retry-delay 3 ${URL} | tar xz || rc=$?
          if [ ! -z "$rc" ]; then
              echo "==> There was an error downloading the binary file. Switching to incremental download."
              echo "==> Downloading file..."
              binaryIncrementalDownload ${BINARY_FILE} ${URL}
	  else
	      echo "==> Done."
          fi
      fi
}

binariesInstall() {
  echo "===> Downloading version ${FABRIC_TAG} platform specific fabric binaries"
  # wget https://hub.fastgit.org/hyperledger/fabric/releases/download/v1.4.8/hyperledger-fabric-linux-amd64-1.4.8.tar.gz
  binaryDownload ${BINARY_FILE} https://hub.fastgit.org/hyperledger/fabric/releases/download/v${VERSION}/${BINARY_FILE}
  if [ $? -eq 22 ]; then
     echo
     echo "------> ${FABRIC_TAG} platform specific fabric binary is not available to download <----"
     echo
   fi

  echo "===> Downloading version ${CA_TAG} platform specific fabric-ca-client binary"
  binaryDownload ${CA_BINARY_FILE} https://hub.fastgit.org/hyperledger/fabric-ca/releases/download/v${CA_VERSION}/${CA_BINARY_FILE}
  if [ $? -eq 22 ]; then
     echo
     echo "------> ${CA_TAG} fabric-ca-client binary is not available to download  (Available from 1.1.0-rc1) <----"
     echo
   fi
}

dockerInstall() {
  which docker >& /dev/null
  NODOCKER=$?
  if [ "${NODOCKER}" == 0 ]; then
	  echo "===> Pulling fabric Images"
	  dockerFabricPull ${FABRIC_TAG}
	  echo "===> Pulling fabric ca Image"
	  dockerCaPull ${CA_TAG}
	  echo "===> Pulling thirdparty docker images"
	  dockerThirdPartyImagesPull ${THIRDPARTY_TAG}
	  echo
	  echo "===> List out hyperledger docker images"
	  docker images | grep hyperledger*
  else
    echo "========================================================="
    echo "Docker not installed, bypassing download of Fabric images"
    echo "========================================================="
  fi
}

DOCKER=true
SAMPLES=true
BINARIES=true

# Parse commandline args pull out
# version and/or ca-version strings first
if [ ! -z "$1" -a ${1:0:1} != "-" ]; then
  VERSION=$1;shift
  if [ ! -z "$1"  -a ${1:0:1} != "-" ]; then
    CA_VERSION=$1;shift
    if [ ! -z "$1"  -a ${1:0:1} != "-" ]; then
      THIRDPARTY_IMAGE_VERSION=$1;shift
    fi
  fi
fi

# prior to 1.2.0 architecture was determined by uname -m
if [[ $VERSION =~ ^1\.[0-1]\.* ]]; then
  export FABRIC_TAG=${MARCH}-${VERSION}
  export CA_TAG=${MARCH}-${CA_VERSION}
  export THIRDPARTY_TAG=${MARCH}-${THIRDPARTY_IMAGE_VERSION}
else
  # starting with 1.2.0, multi-arch images will be default
  : ${CA_TAG:="$CA_VERSION"}
  : ${FABRIC_TAG:="$VERSION"}
  : ${THIRDPARTY_TAG:="$THIRDPARTY_IMAGE_VERSION"}
fi

BINARY_FILE=hyperledger-fabric-${ARCH}-${VERSION}.tar.gz
CA_BINARY_FILE=hyperledger-fabric-ca-${ARCH}-${CA_VERSION}.tar.gz

# then parse opts
while getopts "h?dsb" opt; do
  case "$opt" in
    h|\?)
      printHelp
      exit 0
    ;;
    d)  DOCKER=false
    ;;
    s)  SAMPLES=false
    ;;
    b)  BINARIES=false
    ;;
  esac
done

if [ "$SAMPLES" == "true" ]; then
  echo
  echo "Installing hyperledger/fabric-samples repo"
  echo
  samplesInstall
fi
if [ "$BINARIES" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric binaries"
  echo
  binariesInstall
fi
if [ "$DOCKER" == "true" ]; then
  echo
  echo "Installing Hyperledger Fabric docker images"
  echo
  dockerInstall
fi

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