fabric使用配置文件configtx.yaml生成创世区块时遇到的坑

首先我的fabric版本是2.3.0，在参考冯翔老师的《区块链开发实战》之Hyperledger fabric关键技术这本书上的配置文件configtx.yaml生成创世区块时出现了很多问题。
书上的配置文件configtx.yaml内容为：

Profiles:
    TestTwoOrgsOrdererGenesis:
        Orderer:
            <<: *OrdererDefaults
            Organizations:
                - *OrdererOrg
        Consortiums:
            SampleConsortium:
                Organizations:
                    - *Org1
                    - *Org2
    TestTwoOrgsChannel:
        Consortium: SampleConsortium
        Application:
            <<: *ApplicationDefaults
            Organizations:
                - *Org1
                - *Org2
Organizations:
    - &OrdererOrg
        Name: OrdererOrg
        ID: OrdererMSP
        MSPDir: crypto-config/ordererOrganizations/example.com/msp

    - &Org1
        Name: Org1MSP
        ID: Org1MSP
        MSPDir: crypto-config/peerOrganizations/org1.example.com/msp
        AnchorPeers:
            - Host: peer0.org1.example.com
              Port: 7051
    - &Org2
        Name: Org2MSP
        ID: Org2MSP
        MSPDir: crypto-config/peerOrganizations/org2.example.com/msp
        AnchorPeers:
            - Host: peer0.org2.example.com
              Port: 7051
Orderer: &OrdererDefaults
    OrdererType: solo
    Addresses:
        - orderer.example.com:7050
    BatchTimeout: 2s
    BatchSize:
        MaxMessageCount: 10
        AbsoluteMaxBytes: 99 MB
        PreferredMaxBytes: 512 KB
    Kafka:
        Brokers:
            - 127.0.0.1:9092
    Organizations:
Application: &ApplicationDefaults
    Organizations:

上述的配置文件在fabric2.3.0中出现了以下问题：

Error 1：Error reading configuration: While parsing config: yaml: unknown anchor 'OrdererDefaults' referenced [recovered]

因为使用的是最新版本，与书本上的版本不同，而最新版本在结构上做了一些改动。在使用‘*’之前，一定要有‘&’定义过了。所以需要把Profiles的内容移到最后。

Error 2：Error reading configuration: yaml: line 50: did not find expected key

这个是空格出了问题，在提示的行号附近检查空格是否出错。.yaml文件不能使用tab键。

Error 3：Error reading configuration: yaml: map merge requires map or sequence of maps as the value

这个错误说的是什么映射的问题。我实在不知道我的configtx.yaml到底是哪里写错了，因为我刚开始是手打的，就有很多空格问题啊等等。这个问题在StackOverflow上有解答：
就是本文Error 1里提到的，然而没有用。
最后是直接复制可以用的configtx.yaml，在上面进行修改，切记不要修改空格。就没有这些问题了。

Error 4：Error on outputBlock: could not create bootstrapper: could not create channel group: error adding policies to channel group: no policies defined

这个错误也是因为新版本！在configtx.yaml中要有相对应的policies才行。

我根据fabric-samples里面的配置文件修改了configtx.yaml。
修正后的configtx.yaml：

Organizations:
    - &OrdererOrg
        Name: OrdererOrg
        ID: OrdererMSP
        MSPDir: ../fabricconfig/crypto-config/ordererOrganizations/example.com/msp
        Policies:
            Readers:
                Type: Signature
                Rule: "OR('OrdererMSP.member')"
            Writers:
                Type: Signature
                Rule: "OR('OrdererMSP.member')"
            Admins:
                Type: Signature
                Rule: "OR('OrdererMSP.admin')"

    - &Org1
        Name: Org1MSP
        ID: Org1MSP
        MSPDir: ../fabricconfig/crypto-config/peerOrganizations/org1.example.com/msp
        Policies:
            Readers:
                Type: Signature
                Rule: "OR('Org1MSP.admin', 'Org1MSP.peer', 'Org1MSP.client')"
            Writers:
                Type: Signature
                Rule: "OR('Org1MSP.admin', 'Org1MSP.client')"
            Admins:
                Type: Signature
                Rule: "OR('Org1MSP.admin')"
            Endorsement:
                Type: Signature
                Rule: "OR('Org1MSP.peer')"
        AnchorPeers:
            - Host: peer0.org1.example.com
              Port: 7051
    - &Org2
        Name: Org2MSP
        ID: Org2MSP
        MSPDir: ../fabricconfig/crypto-config/peerOrganizations/org2.example.com/msp
        Policies:
            Readers:
                Type: Signature
                Rule: "OR('Org2MSP.admin', 'Org2MSP.peer', 'Org2MSP.client')"
            Writers:
                Type: Signature
                Rule: "OR('Org2MSP.admin', 'Org2MSP.client')"
            Admins:
                Type: Signature
                Rule: "OR('Org2MSP.admin')"
            Endorsement:
                Type: Signature
                Rule: "OR('Org2MSP.peer')"
        AnchorPeers:
            - Host: peer0.org2.example.com
              Port: 7051
Capabilities:
    Channel: &ChannelCapabilities
        V2_0: true

    Orderer: &OrdererCapabilities
        V2_0: true

    Application: &ApplicationCapabilities
        V2_0: true

Application: &ApplicationDefaults
    Organizations:

    Policies: &ApplicationDefaultPolicies
        LifecycleEndorsement:
            Type: ImplicitMeta
            Rule: "MAJORITY Endorsement"
        Endorsement:
            Type: ImplicitMeta
            Rule: "MAJORITY Endorsement"
        Readers:
            Type: ImplicitMeta
            Rule: "ANY Readers"
        Writers:
            Type: ImplicitMeta
            Rule: "ANY Writers"
        Admins:
            Type: ImplicitMeta
            Rule: "MAJORITY Admins"

    Capabilities:
        <<: *ApplicationCapabilities

Orderer: &OrdererDefaults
    OrdererType: solo
    Addresses:
        - orderer.example.com:7050
    BatchTimeout: 2s
    BatchSize:
        MaxMessageCount: 10
        AbsoluteMaxBytes: 99 MB
        PreferredMaxBytes: 512 KB
    Kafka:
        Brokers:
            - 127.0.0.1:9092
    Organizations:

    Policies:
        Readers:
            Type: ImplicitMeta
            Rule: "ANY Readers"
        Writers:
            Type: ImplicitMeta
            Rule: "ANY Writers"
        Admins:
            Type: ImplicitMeta
            Rule: "MAJORITY Admins"
        BlockValidation:
            Type: ImplicitMeta
            Rule: "ANY Writers"
            
    Capabilities:
        <<: *OrdererCapabilities


Channel: &ChannelDefaults
    Policies:
        # Who may invoke the 'Deliver' API
        Readers:
            Type: ImplicitMeta
            Rule: "ANY Readers"
        # Who may invoke the 'Broadcast' API
        Writers:
            Type: ImplicitMeta
            Rule: "ANY Writers"
        # By default, who may modify elements at this config level
        Admins:
            Type: ImplicitMeta
            Rule: "MAJORITY Admins"


    Capabilities:
        <<: *ChannelCapabilities


Profiles:
    TestTwoOrgsOrdererGenesis:
        <<: *ChannelDefaults
        Orderer:
            <<: *OrdererDefaults
            Organizations:
                - *OrdererOrg
        Consortiums:
            SampleConsortium:
                Organizations:
                    - *Org1
                    - *Org2
    TestTwoOrgsChannel:
        Consortium: SampleConsortium
        Application:
            <<: *ApplicationDefaults
            Organizations:
                - *Org1
                - *Org2

还有个需要注意的是MSPDir的值是相对路径。
成功生成创世区块：