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原文链接:Fabric网络环境启动过程详解原文已更新，请读者前往原文阅读
这篇文章对fabric的网络环境启动过程进行讲解,也就是我们上节讲到的启动测试fabric网络环境时运行network_setup.sh这个文件的执行流程
fabric网络环境启动过程详解
上一节我们讲到 fabric网络环境的启动测试，主要是使用 ./network_setup.sh up 这个命令，所以fabric网络环境启动的重点就在network_setup.sh这个文件中。接下来我们就分析一下network_setup.sh这个文件
network_setup.sh其中包括两个部分，一个是利用generateArtifacts.sh脚本文件配置组织关系和颁发证书、公/私钥、通道证书等，另一个是docker-compose-cli.yaml用于根据配置启动集群并测试chaincode的示例代码。下面是具体的流程图介绍：
首先看下generateArtifacts.sh脚本文件，它包含三个函数，分别是：
1.generateCerts：
该函数使用cryptogen工具根据crypto-config.yaml来生成公私钥和证书信息等。
2.replacePrivateKey：
将docker-compose-e2e-template.yaml文档中的ca私钥替换成具体的私钥。
3.generateChannelArtifacts：
使用configtxgen工具根据configtx.yaml文件来生成创世区块和通道相关信息，更新锚节点。接着是docker-compose-cli.yaml文件
docker-compose-cli.yaml文件根据组织关系启动docker集群，并在cli容器中执行command命令运行./scripts/script.sh脚本文件。 那./scripts/script.sh脚本具体做了什么呢？
1.createChannel：创建channel。
2. joinChannel：将每个peer节点加入channel。
3. updateAnchorPeers：更新锚节点
4. installChaincode：部署chaincode。
5. instantiateChaincode：初始化chaincode。
6. chaincodeQuery：chaincode查询另外docker-compose-cli.yaml这个文件还有一个配置项是需要注意的地方，那就是：
file: base/docker-compose-base.yaml这里的docker-compose-base.yaml其实就是Orderer和peer的基础配置文件，包括指定端口等。
几个重要的配置文件
1.crypto-config.yaml
基于crypto-config.yaml（此文件在../fabric/examples/e2e_cli中）生成公、私钥和证书信息，并保存在crypto-config文件夹中。另外crypto-config.yaml还定义了组织成员以及组织下的peer节点个数。
crypto-config.yaml文件讲解：
字段Name和Domain就是关于这个组织的名字和域名，这主要是用于生成证书的时候，证书内会包含该信息。而Template.Count=2是说我们要生成2套公私钥和证书，一套是peer0.org1的，还有一套是peer1.org1的（也就指定了org中存在peer0和peer1两个节点）。最后Users.Count=1是说每个Template下面会有几个普通User（注意，Admin是Admin，不包含在这个计数中），这里配置了1，也就是说我们只需要一个普通用户User1@org1.example.com 我们可以根据实际需要调整这个配置文件，增删Org Users等。文件内容如下：
# ---------------------------------------------------------------------------
# Orderer
# ---------------------------------------------------------------------------
- Name: Orderer
Domain: example.com
# ---------------------------------------------------------------------------
# "Specs" - See PeerOrgs below for complete description
# ---------------------------------------------------------------------------
Specs:
- Hostname: orderer
# ---------------------------------------------------------------------------
# "PeerOrgs" - Definition of organizations managing peer nodes
# ---------------------------------------------------------------------------
PeerOrgs:
# ---------------------------------------------------------------------------
# Org1
# ---------------------------------------------------------------------------
- Name: Org1
Domain: org1.example.com
# ---------------------------------------------------------------------------
# "Specs"
# ---------------------------------------------------------------------------
# Uncomment this section to enable the explicit definition of hosts in your
# configuration. Most users will want to use Template, below
#
# Specs is an array of Spec entries. Each Spec entry consists of two fields:
# - Hostname: (Required) The desired hostname, sans the domain.
# - CommonName: (Optional) Specifies the template or explicit override for
# the CN. By default, this is the template:
#
# "{{.Hostname}}.{{.Domain}}"
#
# which obtains its values from the Spec.Hostname and
# Org.Domain, respectively.
# ---------------------------------------------------------------------------
# Specs:
# - Hostname: foo # implicitly "foo.org1.example.com"
# CommonName: foo27.org5.example.com # overrides Hostname-based FQDN set above
# - Hostname: bar
# - Hostname: baz
# ---------------------------------------------------------------------------
# "Template"
# ---------------------------------------------------------------------------
# Allows for the definition of 1 or more hosts that are created sequentially
# from a template. By default, this looks like "peer%d" from 0 to Count-1.
# You may override the number of nodes (Count), the starting index (Start)
# or the template used to construct the name (Hostname).
#
# Note: Template and Specs are not mutually exclusive. You may define both
# sections and the aggregate nodes will be created for you. Take care with
# name collisions
# ---------------------------------------------------------------------------
Template:
Count: 2
# Start: 5
# Hostname: {{.Prefix}}{{.Index}} # default
# ---------------------------------------------------------------------------
# "Users"
# ---------------------------------------------------------------------------
# Count: The number of user accounts _in addition_ to Admin
# ---------------------------------------------------------------------------
Users:
Count: 1
# ---------------------------------------------------------------------------
# Org2: See "Org1" for full specification
# ---------------------------------------------------------------------------
- Name: Org2
Domain: org2.example.com
Template:
Count: 2
Users:
Count: 1
注：
peer：
Fabric 网络中的节点，表现为一个运行着的docker容器。可以与网络中的其他peer进行通信，每个peer都在本地保留一份ledger的副本。它是org下的组织成员。
org:
一个组织，它可以由一个或多个peer组成。
Orderer :
联盟成员共享的中心化节点。用来对交易进行排序，是 Fabric 共识机制的重要组成部分。
2.configtx.yaml
基于configtx.yaml（此文件在../fabric/examples/e2e_cli中）生成创世区块和通道相关信息，并保存在channel-artifacts文件夹。还可以指定背书策略。
configtx.yaml文件讲解：
1.官方提供的examples/e2e_cli/configtx.yaml这个文件里面配置了由2个Org参与的Orderer共识配置TwoOrgsOrdererGenesis，以及由2个Org参与的Channel配置：TwoOrgsChannel。
2.另外我们可以在此文件的Orderer部分设置共识的算法是Solo还是Kafka，以及共识时区块大小，超时时间等，我们使用默认值即可，不用更改。而Peer节点的配置包含了MSP的配置，锚节点的配置。如果我们有更多的Org，或者有更多的Channel，那么就可以根据模板进行对应的修改。
3.Policies配置也要特别注意，该配置项定义了不同角色的权限,Reader,Writer以及Admin分别对应读，写，以及admin权限,读权限角色只能从别的peer节点同步账本而不能发起交易，只有writer定义项下的角色才拥有发起交易的也就是调用chaincode的invoke方法的权限(不一定都是invoke方案，只要涉及到chaincode中状态修改的方法，都只有拥有writer权限或admin权限的角色才能调用)。以该配置的Organizations配置下的Org1配置为例,"OR('Org1MSP.admin', 'Org1MSP.client')",表示org1的msp服务中的admin或者client角色拥有发起交易的权限。文件内容如下：
# Copyright IBM Corp. All Rights Reserved.
#
# SPDX-License-Identifier: Apache-2.0
#
---
################################################################################
#
# Profile
#
# - Different configuration profiles may be encoded here to be specified
# as parameters to the configtxgen tool
#
################################################################################
Profiles:
TwoOrgsOrdererGenesis:
Orderer:
<<: *OrdererDefaults
Organizations:
- *OrdererOrg
Consortiums:
SampleConsortium:
Organizations:
- *Org1
- *Org2
TwoOrgsChannel:
Consortium: SampleConsortium
Application:
<<: *ApplicationDefaults
Organizations:
- *Org1
- *Org2
################################################################################
#
# Section: Organizations
#
# - This section defines the different organizational identities which will
# be referenced later in the configuration.
#
################################################################################
Organizations:
# SampleOrg defines an MSP using the sampleconfig. It should never be used
# in production but may be used as a template for other definitions
- &OrdererOrg
# DefaultOrg defines the organization which is used in the sampleconfig
# of the fabric.git development environment
Name: OrdererOrg
# ID to load the MSP definition as
ID: OrdererMSP
# MSPDir is the filesystem path which contains the MSP configuration
MSPDir: crypto-config/ordererOrganizations/example.com/msp
- &Org1
# DefaultOrg defines the organization which is used in the sampleconfig
# of the fabric.git development environment
Name: Org1MSP
# ID to load the MSP definition as
ID: Org1MSP
MSPDir: crypto-config/peerOrganizations/org1.example.com/msp
AnchorPeers:
# AnchorPeers defines the location of peers which can be used
# for cross org gossip communication. Note, this value is only
# encoded in the genesis block in the Application section context
- Host: peer0.org1.example.com
Port: 7051
- &Org2
# DefaultOrg defines the organization which is used in the sampleconfig
# of the fabric.git development environment
Name: Org2MSP
# ID to load the MSP definition as
ID: Org2MSP
MSPDir: crypto-config/peerOrganizations/org2.example.com/msp
AnchorPeers:
# AnchorPeers defines the location of peers which can be used
# for cross org gossip communication. Note, this value is only
# encoded in the genesis block in the Application section context
- Host: peer0.org2.example.com
Port: 7051
################################################################################
#
# SECTION: Orderer
#
# - This section defines the values to encode into a config transaction or
# genesis block for orderer related parameters
#
################################################################################
Orderer: &OrdererDefaults
# Orderer Type: The orderer implementation to start
# Available types are "solo" and "kafka"
OrdererType: solo
Addresses:
- orderer.example.com:7050
# Batch Timeout: The amount of time to wait before creating a batch
BatchTimeout: 2s
# Batch Size: Controls the number of messages batched into a block
BatchSize:
# Max Message Count: The maximum number of messages to permit in a batch
MaxMessageCount: 10
# Absolute Max Bytes: The absolute maximum number of bytes allowed for
# the serialized messages in a batch.
AbsoluteMaxBytes: 98 MB
# Preferred Max Bytes: The preferred maximum number of bytes allowed for
# the serialized messages in a batch. A message larger than the preferred
# max bytes will result in a batch larger than preferred max bytes.
PreferredMaxBytes: 512 KB
Kafka:
# Brokers: A list of Kafka brokers to which the orderer connects
# NOTE: Use IP:port notation
Brokers:
- 127.0.0.1:9092
# Organizations is the list of orgs which are defined as participants on
# the orderer side of the network
Organizations:
################################################################################
#
# SECTION: Application
#
# - This section defines the values to encode into a config transaction or
# genesis block for application related parameters
#
################################################################################
Application: &ApplicationDefaults
# Organizations is the list of orgs which are defined as participants on
# the application side of the network
Organizations:
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