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  2. Fabric1.4：运行 first-network 网络

Fabric1.4：运行 first-network 网络

由 假如想象 提交于 2020-05-02 18:14:52

说明：运行 first-network 网络，必须先安装好 fabric1.4 的预置环境，fabric1.4 的安装可以参考此博文：https://www.cnblogs.com/zongmin/p/11635686.html 。本文使用 fabric 版本为 v1.4.3，其它版本的 first-network 网络配置可能不同。

构建你的第一个网络（Build Your First network，BYFN）提供了一个 fabric 的示例网络。该示例网络中由两个组织构成，每个组织维护两个 peer 节点，默认使用 solo 共识服务。

1 脚本 byfn.sh

first-network 中有一个启动脚本 byfn.sh，利用构建的 Docker 镜像快速启动网络。该脚本会启动一个 orderer 节点和四个归属两个不同组织的 peer 节点，还将启动一个容器运行脚本，它将 peer 节点加入通道（Channel）、部署和实例化链码，并根据已部署的链码驱动交易执行。

以下是 byfn.sh 脚本的帮助文档：

$ ./byfn.sh
Usage: 
  byfn.sh <mode> [-c <channel name>] [-t <timeout>] [-d <delay>] [-f <docker-compose-file>] [-s <dbtype>] [-l <language>] [-o <consensus-type>] [-i <imagetag>] [-a] [-n] [-v]
    <mode> - one of 'up', 'down', 'restart', 'generate' or 'upgrade'
      - 'up' - bring up the network with docker-compose up
      - 'down' - clear the network with docker-compose down
      - 'restart' - restart the network
      - 'generate' - generate required certificates and genesis block
      - 'upgrade'  - upgrade the network from version 1.3.x to 1.4.0
    -c <channel name> - channel name to use (defaults to "mychannel")
    -t <timeout> - CLI timeout duration in seconds (defaults to 10)
    -d <delay> - delay duration in seconds (defaults to 3)
    -f <docker-compose-file> - specify which docker-compose file use (defaults to docker-compose-cli.yaml)
    -s <dbtype> - the database backend to use: goleveldb (default) or couchdb
    -l <language> - the chaincode language: golang (default) or node
    -o <consensus-type> - the consensus-type of the ordering service: solo (default), kafka, or etcdraft
    -i <imagetag> - the tag to be used to launch the network (defaults to "latest")
    -a - launch certificate authorities (no certificate authorities are launched by default)
    -n - do not deploy chaincode (abstore chaincode is deployed by default)
    -v - verbose mode
  byfn.sh -h (print this message)

Typically, one would first generate the required certificates and 
genesis block, then bring up the network. e.g.:

  byfn.sh generate -c mychannel
  byfn.sh up -c mychannel -s couchdb
        byfn.sh up -c mychannel -s couchdb -i 1.4.0
  byfn.sh up -l node
  byfn.sh down -c mychannel
        byfn.sh upgrade -c mychannel

Taking all defaults:
  byfn.sh generate
  byfn.sh up
  byfn.sh down
  • -c：设置通道名称，默认为 mychannel，例：./byfn.sh up -c testchannel
  • -t：设置 CLI 超时参数，不设置的情况下 CLI 将放弃 10 秒后发出查询请求的默认设置
  • -l：设置智能合约的语言，默认是 go，例：./byfn.sh up -l java
  • -o：设置排序服务方式，默认是 solo，例：./byfn.sh up -o kafka

<br>

2 生成证书

执行如下命令：

$ ./byfn.sh generate

运行该命令会为 fabric 网络的各种实体生成所需的证书与密钥，保存在 crypto-config 目录下。

Generating certs and genesis block for channel 'mychannel' with CLI timeout of '10' seconds and CLI delay of '3' seconds
Continue? [Y/n] y
proceeding ...
/Users/xxx/dev/fabric-samples/bin/cryptogen

##########################################################
##### Generate certificates using cryptogen tool #########
##########################################################
org1.example.com
2017-06-12 21:01:37.334 EDT [bccsp] GetDefault -> WARN 001 Before using BCCSP, please call InitFactories(). Falling back to bootBCCSP.
...

/Users/xxx/dev/fabric-samples/bin/configtxgen
##########################################################
#########  Generating Orderer Genesis block ##############
##########################################################
2017-06-12 21:01:37.558 EDT [common/configtx/tool] main -> INFO 001 Loading configuration
2017-06-12 21:01:37.562 EDT [msp] getMspConfig -> INFO 002 intermediate certs folder not found at [/Users/xxx/dev/byfn/crypto-config/ordererOrganizations/example.com/msp/intermediatecerts]. Skipping.: [stat /Users/xxx/dev/byfn/crypto-config/ordererOrganizations/example.com/msp/intermediatecerts: no such file or directory]
...
2017-06-12 21:01:37.588 EDT [common/configtx/tool] doOutputBlock -> INFO 00b Generating genesis block
2017-06-12 21:01:37.590 EDT [common/configtx/tool] doOutputBlock -> INFO 00c Writing genesis block

#################################################################
### Generating channel configuration transaction 'channel.tx' ###
#################################################################
2017-06-12 21:01:37.634 EDT [common/configtx/tool] main -> INFO 001 Loading configuration
2017-06-12 21:01:37.644 EDT [common/configtx/tool] doOutputChannelCreateTx -> INFO 002 Generating new channel configtx
2017-06-12 21:01:37.645 EDT [common/configtx/tool] doOutputChannelCreateTx -> INFO 003 Writing new channel tx

#################################################################
#######    Generating anchor peer update for Org1MSP   ##########
#################################################################
2017-06-12 21:01:37.674 EDT [common/configtx/tool] main -> INFO 001 Loading configuration
2017-06-12 21:01:37.678 EDT [common/configtx/tool] doOutputAnchorPeersUpdate -> INFO 002 Generating anchor peer update
2017-06-12 21:01:37.679 EDT [common/configtx/tool] doOutputAnchorPeersUpdate -> INFO 003 Writing anchor peer update

#################################################################
#######    Generating anchor peer update for Org2MSP   ##########
#################################################################
2017-06-12 21:01:37.700 EDT [common/configtx/tool] main -> INFO 001 Loading configuration
2017-06-12 21:01:37.704 EDT [common/configtx/tool] doOutputAnchorPeersUpdate -> INFO 002 Generating anchor peer update
2017-06-12 21:01:37.704 EDT [common/configtx/tool] doOutputAnchorPeersUpdate -> INFO 003 Writing anchor peer update

<br>

3 启动网络

使用如下命令启动 fabric 网络：

$ ./byfn.sh up

注意：该命令会检查网络实体的证书是否生成，如果没有会先生成证书。因此，可以直接执行 ./byfn.sh up 命令，而无需执行 ./byfn.sh generate 命令。

执行日志如下：

Starting for channel 'mychannel' with CLI timeout of '10' seconds and CLI delay of '3' seconds
Continue? [Y/n]
proceeding ...
Creating network "net_byfn" with the default driver
Creating peer0.org1.example.com
Creating peer1.org1.example.com
Creating peer0.org2.example.com
Creating orderer.example.com
Creating peer1.org2.example.com
Creating cli

 ____    _____      _      ____    _____
/ ___|  |_   _|    / \    |  _ \  |_   _|
\___ \    | |     / _ \   | |_) |   | |
 ___) |   | |    / ___ \  |  _ <    | |
|____/    |_|   /_/   \_\ |_| \_\   |_|

Channel name : mychannel
Creating channel...

启动所有容器，然后驱动完整的应用程序场景。执行成功后，在终端会出现如下输出：

Query Result: 90
2017-05-16 17:08:15.158 UTC [main] main -> INFO 008 Exiting.....
===================== Query successful on peer1.org2 on channel 'mychannel' =====================

===================== All GOOD, BYFN execution completed =====================


 _____   _   _   ____
| ____| | \ | | |  _ \
|  _|   |  \| | | | | |
| |___  | |\  | | |_| |
|_____| |_| \_| |____/

屏幕后面发生了什么？

./byfn.sh up 启动完 orderer 节点、peer 节点和 CLI 容器之后，实际是调用 script.sh 脚本，该脚本是在 CLI 容器中执行，script.sh 脚本完成客户端交易执行操作。下面是 CLI 容器的定义，CLI 容器其实就是用户客户端，只不过是命令行客户端，运行在容器中。默认情况下，CLI 的身份是 admin.org1，连接 peer0.org1 节点，执行 script.sh 脚本。

  cli:
    container_name: cli
    image: hyperledger/fabric-tools:$IMAGE_TAG
    tty: true
    stdin_open: true
    environment:
      - SYS_CHANNEL=$SYS_CHANNEL
      - GOPATH=/opt/gopath
      - CORE_VM_ENDPOINT=unix:///host/var/run/docker.sock
      #- FABRIC_LOGGING_SPEC=DEBUG
      - FABRIC_LOGGING_SPEC=INFO
      - CORE_PEER_ID=cli
      - CORE_PEER_ADDRESS=peer0.org1.example.com:7051
      - CORE_PEER_LOCALMSPID=Org1MSP
      - CORE_PEER_TLS_ENABLED=true
      - CORE_PEER_TLS_CERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/server.crt
      - CORE_PEER_TLS_KEY_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/server.key
      - CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt
      - CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/Admin@org1.example.com/msp
    working_dir: /opt/gopath/src/github.com/hyperledger/fabric/peer
    command: /bin/bash
    volumes:
        - /var/run/:/host/var/run/
        - ./../chaincode/:/opt/gopath/src/github.com/chaincode
        - ./crypto-config:/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/
        - ./scripts:/opt/gopath/src/github.com/hyperledger/fabric/peer/scripts/
        - ./channel-artifacts:/opt/gopath/src/github.com/hyperledger/fabric/peer/channel-artifacts
    depends_on:
      - orderer.example.com
      - peer0.org1.example.com
      - peer1.org1.example.com
      - peer0.org2.example.com
      - peer1.org2.example.com
    networks:
      - byfn

下面简略描述 script.sh 的基本函数。

3.1 创建通道

createChannel() {
	setGlobals 0 1    # admin.org1 连接 peer0.org1

	if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
                set -x
		peer channel create -o orderer.example.com:7050 -c $CHANNEL_NAME -f ./channel-artifacts/channel.tx >&log.txt
		res=$?
                set +x
	else
				set -x
		peer channel create -o orderer.example.com:7050 -c $CHANNEL_NAME -f ./channel-artifacts/channel.tx --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA >&log.txt
		res=$?
				set +x
	fi
	cat log.txt
	verifyResult $res "Channel creation failed"
	echo "===================== Channel '$CHANNEL_NAME' created ===================== "
	echo
}

admin.org1 连接 peer0.org1 节点，向 orderer 节点传递要创建的通道名称 $CHANNEL_NAME （默认为 mychannel）和通道配置交易 channel.tx。如果创建成功，则返回通道的创世区块 $CHANNEL_NANE.block，该区块包含 channel.tx 指定的通道配置信息，保存在 CLI 容器中。

<br>

3.2 加入通道

joinChannel () {
	for org in 1 2; do
	    for peer in 0 1; do
		joinChannelWithRetry $p$CHANNEL_NAMEeer $org
		echo "===================== peer${peer}.org${org} joined channel '$CHANNEL_NAME' ===================== "
		sleep $DELAY
		echo
	    done
	done
}

第一个 for 循环标识两个组织 org1 和 org2；第二个 for 循环标识两个组织 peer0 和 peer1。根据 $peer $org 先后顺序，四个节点分别是：

  • peer0.org1.example.com
  • peer1.org1.example.com
  • peer0.org2.example.com
  • peer1.org2.example.com

这是 first-network 的默认网络结构，在 crypto-config.yaml 文件的 TwoOrgsChannel 部分定义，MSP 路径在 docker-compose-cli.yaml 文件中定义。

## Sometimes Join takes time hence RETRY at least 5 times
joinChannelWithRetry() {
  PEER=$1
  ORG=$2
  setGlobals $PEER $ORG

  set -x
  peer channel join -b $CHANNEL_NAME.block >&log.txt
  res=$?
  set +x
  cat log.txt
  if [ $res -ne 0 -a $COUNTER -lt $MAX_RETRY ]; then
    COUNTER=$(expr $COUNTER + 1)
    echo "peer${PEER}.org${ORG} failed to join the channel, Retry after $DELAY seconds"
    sleep $DELAY
    joinChannelWithRetry $PEER $ORG
  else
    COUNTER=1
  fi
  verifyResult $res "After $MAX_RETRY attempts, peer${PEER}.org${ORG} has failed to join channel '$CHANNEL_NAME' "
}

在 joinChannelWithRetry 函数中的 setGlobals 是设置 CLI 容器的环境变量的函数。例如：setGlobals 1 2 设置 CLI 的身份为 admin.org2，连接 peer1.org2 节点。

使用 peer channel join 命令让节点加入通道，$CHANNEL_NAME.block 就是前面创建通道成功时返回的区块，该区块在上面 peer0.org1 创建通道时保持在 CLI 容器内，所以能直接使用。节点成功加入通道后会创建 CHANNEL_NAME.block 开头的链。

<br>

3.3 更新锚节点

一个组织只能有一个锚节点，节点加入通道后才能进行更新。

updateAnchorPeers() {
  PEER=$1
  ORG=$2
  setGlobals $PEER $ORG

  if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
    set -x
    peer channel update -o orderer.example.com:7050 -c $CHANNEL_NAME -f ./channel-artifacts/${CORE_PEER_LOCALMSPID}anchors.tx >&log.txt
    res=$?
    set +x
  else
    set -x
    peer channel update -o orderer.example.com:7050 -c $CHANNEL_NAME -f ./channel-artifacts/${CORE_PEER_LOCALMSPID}anchors.tx --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA >&log.txt
    res=$?
    set +x
  fi
  cat log.txt
  verifyResult $res "Anchor peer update failed"
  echo "===================== Anchor peers updated for org '$CORE_PEER_LOCALMSPID' on channel '$CHANNEL_NAME' ===================== "
  sleep $DELAY
  echo
}

更新 org1 的锚节点 peer0.org1.example.com 和 org2 的锚节点 peer0.org2.example.com 。过程是将 Org1MSPanchors.tx 和 Org2MSPanchors.tx 交易连同通道名称 $CHANNEL_NAME 传递给 orderer。

<br>

3.4 安装链码

installChaincode() {
  PEER=$1
  ORG=$2
  setGlobals $PEER $ORG
  VERSION=${3:-1.0}
  set -x
  peer chaincode install -n mycc -v ${VERSION} -l ${LANGUAGE} -p ${CC_SRC_PATH} >&log.txt
  res=$?
  set +x
  cat log.txt
  verifyResult $res "Chaincode installation on peer${PEER}.org${ORG} has failed"
  echo "===================== Chaincode is installed on peer${PEER}.org${ORG} ===================== "
  echo
}

安装链码需要指定链码的配置信息，-n 是链码的名称；-v 是版本号；-l 是指定链码的语言，如果不使用该标志默认使用 go 语言；-p 是指向链码路径，默认是 github.com/chaincode/chaincode_example02/go/。

<br>

3.5 实例化链码

instantiateChaincode() {
  PEER=$1
  ORG=$2
  setGlobals $PEER $ORG
  VERSION=${3:-1.0}

  # while 'peer chaincode' command can get the orderer endpoint from the peer
  # (if join was successful), let's supply it directly as we know it using
  # the "-o" option
  if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
    set -x
    peer chaincode instantiate -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc -l ${LANGUAGE} -v ${VERSION} -c '{"Args":["init","a","100","b","200"]}' -P "AND ('Org1MSP.peer','Org2MSP.peer')" >&log.txt
    res=$?
    set +x
  else
    set -x
    peer chaincode instantiate -o orderer.example.com:7050 --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc -l ${LANGUAGE} -v 1.0 -c '{"Args":["init","a","100","b","200"]}' -P "AND ('Org1MSP.peer','Org2MSP.peer')" >&log.txt
    res=$?
    set +x
  fi
  cat log.txt
  verifyResult $res "Chaincode instantiation on peer${PEER}.org${ORG} on channel '$CHANNEL_NAME' failed"
  echo "===================== Chaincode is instantiated on peer${PEER}.org${ORG} on channel '$CHANNEL_NAME' ===================== "
  echo
}

fabric 网络上的链码是多次安装，一次实例化，该函数只需运行一遍即可。

链码在通道 $CHANNEL_NAME 上实例化。实例化将链码添加到通道上，启动目标节点的容器，初始化与链码相关的初始值，这里的初始值为 ["a","100","b","200"]。”实例化“ 过程会产生链码的容器，例如： dev-peer0-org1.example.com-mycc-1.0 。实例化过程需要指定背书策略，通过 -P 参数设置，这里的策略定义为 AND ('Org1MSP.peer','Org2MSP.peer') ，表示任何交易必须要有 org1 和 org2 节点的共同背书。此处背书的节点只能是以下四对组合：

  • peer0.org1.example.com 和 peer0.org2.example.com
  • peer0.org1.example.com 和 peer1.org2.example.com
  • peer1.org1.example.com 和 peer0.org2.example.com
  • peer1.org1.example.com 和 peer1.org2.example.com

<br>

3.6 调用链码

# chaincodeInvoke <peer> <org> ...
# Accepts as many peer/org pairs as desired and requests endorsement from each
chaincodeInvoke() {
  parsePeerConnectionParameters $@
  res=$?
  verifyResult $res "Invoke transaction failed on channel '$CHANNEL_NAME' due to uneven number of peer and org parameters "

  # while 'peer chaincode' command can get the orderer endpoint from the
  # peer (if join was successful), let's supply it directly as we know
  # it using the "-o" option
  if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
    set -x
    peer chaincode invoke -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc $PEER_CONN_PARMS -c '{"Args":["invoke","a","b","10"]}' >&log.txt
    res=$?
    set +x
  else
    set -x
    peer chaincode invoke -o orderer.example.com:7050 --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc $PEER_CONN_PARMS -c '{"Args":["invoke","a","b","10"]}' >&log.txt
    res=$?
    set +x
  fi
  cat log.txt
  verifyResult $res "Invoke execution on $PEERS failed "
  echo "===================== Invoke transaction successful on $PEERS on channel '$CHANNEL_NAME' ===================== "
  echo
}

向 $PEER_CONN_PARM 发送一个调用，以实现从 a 中转移 10 给 b。$PEER_CONN_PARM 就是上面四对组合中的任意一对背书节点。在调用链码的过程中，如果某个节点的链码容器还没有启动，就会执行启动。

<br>

3.7 查询链码

chaincodeQuery() {
  PEER=$1
  ORG=$2
  setGlobals $PEER $ORG
  EXPECTED_RESULT=$3
  echo "===================== Querying on peer${PEER}.org${ORG} on channel '$CHANNEL_NAME'... ===================== "
  local rc=1
  local starttime=$(date +%s)

  # continue to poll
  # we either get a successful response, or reach TIMEOUT
  while
    test "$(($(date +%s) - starttime))" -lt "$TIMEOUT" -a $rc -ne 0
  do
    sleep $DELAY
    echo "Attempting to Query peer${PEER}.org${ORG} ...$(($(date +%s) - starttime)) secs"
    set -x
    peer chaincode query -C $CHANNEL_NAME -n mycc -c '{"Args":["query","a"]}' >&log.txt
    res=$?
    set +x
    test $res -eq 0 && VALUE=$(cat log.txt | awk '/Query Result/ {print $NF}')
    test "$VALUE" = "$EXPECTED_RESULT" && let rc=0
    # removed the string "Query Result" from peer chaincode query command
    # result. as a result, have to support both options until the change
    # is merged.
    test $rc -ne 0 && VALUE=$(cat log.txt | egrep '^[0-9]+$')
    test "$VALUE" = "$EXPECTED_RESULT" && let rc=0
  done
  echo
  cat log.txt
  if test $rc -eq 0; then
    echo "===================== Query successful on peer${PEER}.org${ORG} on channel '$CHANNEL_NAME' ===================== "
  else
    echo "!!!!!!!!!!!!!!! Query result on peer${PEER}.org${ORG} is INVALID !!!!!!!!!!!!!!!!"
    echo "================== ERROR !!! FAILED to execute End-2-End Scenario =================="
    echo
    exit 1
  fi
}

向装有链码的节点发送一个查询查看 a 的值。如果返回值为 90，则表明在之前的交易中 “a” 的值被减去 10。

<br>

这证明了什么？

为了能成功地对账本进行读/写操作，链码必须按照在相应的节点上。只有在链码中执行初始化（Init函数）、调用（Invoke函数）交易（读/写），或者查询 “a” 的值，才会为节点启动一个链码容器（交易引起容器的启动）。另外，通道中的所有节点都维护账本的一个精确副本，该副本包括在区块中存储不可变、按顺序排列的记录的区块链，以及用户维护当前账本的状态数据库。

<br>

4 关闭网络

执行下面命令：

$ ./byfn.sh down
Stopping for channel 'mychannel' with CLI timeout of '10' seconds and CLI delay of '3' seconds
Continue? [Y/n] y
proceeding ...
WARNING: The BYFN_CA2_PRIVATE_KEY variable is not set. Defaulting to a blank string.
WARNING: The BYFN_CA1_PRIVATE_KEY variable is not set. Defaulting to a blank string.
Stopping cli                    ... done
Stopping peer1.org1.example.com ... done
Stopping peer1.org2.example.com ... done
Stopping peer0.org1.example.com ... done
Stopping peer0.org2.example.com ... done
Stopping orderer.example.com    ... done
Removing cli                    ... done
Removing peer1.org1.example.com ... done
Removing peer1.org2.example.com ... done
Removing peer0.org1.example.com ... done
Removing peer0.org2.example.com ... done
Removing orderer.example.com    ... done
Removing network net_byfn
Removing volume net_peer0.org3.example.com
WARNING: Volume net_peer0.org3.example.com not found.
Removing volume net_peer1.org3.example.com
WARNING: Volume net_peer1.org3.example.com not found.
Removing volume net_orderer2.example.com
WARNING: Volume net_orderer2.example.com not found.
Removing volume net_orderer.example.com
Removing volume net_peer0.org2.example.com
Removing volume net_peer0.org1.example.com
Removing volume net_peer1.org1.example.com
Removing volume net_peer1.org2.example.com
Removing volume net_orderer5.example.com
WARNING: Volume net_orderer5.example.com not found.
Removing volume net_orderer4.example.com
WARNING: Volume net_orderer4.example.com not found.
Removing volume net_orderer3.example.com
WARNING: Volume net_orderer3.example.com not found.

该命令将关闭网络，删除证书材料和组件，并从 Docker 注册表中删除链码镜像。crypto-config 文件夹会被删除，channel-artifacts 文件夹下的 channel.tx、genesis.block、Org1MSPanchors.tx 和 Org2MSPanchors.tx 这四个文件会被删除。

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参考

  1. 《Hyperledger Fabric 核心技术》

  2. https://hyperledger-fabric.readthedocs.io/en/release-1.4/

标签
Hyperledger Fabric
fabric
go
Solo
Docker
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