Cordform task

This example task creates the following three nodes in the build/nodes directory:

A Notary node, which:

• Provides a validating Notary service.
• Runs the corda-finance CorDapp.

PartyA and PartyB nodes, each of which:

• Does not provide any services.
• Runs the corda-finance CorDapp.
• Has an RPC (Remote Procedure Call) user (user1), which enables you to log in the node via RPC.

All three nodes also include any CorDapps defined in the project’s source directories, even if these CorDapps are not listed in each node’s cordapps setting. As a result, if you run the deployNodes task from the template CorDapp, for example, it will automatically build and add the template CorDapp to each node.

The following example, as defined in the Kotlin CorDapp Template, shows a Cordform task called deployNodes that creates the three nodes described above: Notary, PartyA, and PartyB.

task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
    directory "./build/nodes"
    node {
        name "O=Notary,L=London,C=GB"
        // The Notary will offer a validating Notary service.
        notary = [validating : true]
        p2pPort  10002
        rpcSettings {
            port 10003
            adminPort 10023
        }
        h2Port   10004
        // Starts an internal SSH server providing a management shell on the node.
        sshdPort 2223
        // Includes the corda-finance CorDapp on our node.
        cordapps = ["$corda_release_distribution:corda-finance:$corda_release_version"]
        extraConfig = [
            // Setting the JMX reporter type.
            jmxReporterType: 'JOLOKIA',
            // Setting the H2 address.
            h2Settings: [ address: 'localhost:10030' ]
        ]
    }
    node {
        name "O=PartyA,L=London,C=GB"
        p2pPort  10005
        rpcSettings {
            port 10006
            adminPort 10026
        }
        h2Port   10008
        cordapps = ["$corda_release_distribution:corda-finance:$corda_release_version"]
        // Grants user1 all RPC permissions.
        rpcUsers = [[ user: "user1", "password": "test", "permissions": ["ALL"]]]
    }
    node {
        name "O=PartyB,L=New York,C=US"
        p2pPort  10009
        rpcSettings {
            port 10010
            adminPort 10030
        }
        h2Port   10012
        cordapps = ["$corda_release_distribution:corda-finance:$corda_release_version"]
        // Grants user1 the ability to start the MyFlow flow.
        rpcUsers = [[ user: "user1", "password": "test", "permissions": ["StartFlow.net.corda.flows.MyFlow"]]]
    }
}

The configuration values used in the example are described below.

You can turn deploying the local project’s CorDapp to each node off by adding the following code to your node configuration:

projectCordapp {
    deploy = false
}

The Cordform and Dockerform also support a nodeDefaults block, which can contain configuration common to all nodes, for example:

nodeDefaults {
    cordapp project(':contracts')
    cordapp project(':workflows')
    runSchemaMigration = true
    rpcUsers = [[user: "user1", "password": "test", "permissions": ["ALL"]]
}

You can override these defaults for each node:

node {
    name = "O=Notary,L=London,C=GB"
    notary = [ validating: true ]
    rpcUsers = []
}

Required configuration

• name <string> - use this configuration option to specify the legal identity name of the Corda node. For more information, see myLegalName. For example:

name "O=PartyA,L=London,C=GB"

• p2pAddress <string> - use this configuration option to specify the address/port the node uses for inbound communication from other nodes. For more information, see p2pAddress. Required if p2pPort is not specified. For example:

p2pAddress "example.com:10002"

• p2pPort <integer> - use this configuration option to specify the port the node uses for inbound communication from other nodes. The assumed IP address is localhost. For more information, see p2pAddress. For example:

p2pPort 10006  // "localhost:10006"

• rpcSettings <config> - use this configuration option to specify RPC settings for the node. For more information, see rpcSettings. For example:

rpcSettings {
  port 10006
  adminPort 10026
}

Optional configuration

• notary <config> - use this configuration option to specify the node as a Notary node. Required for Notary nodes. For more information, see notary.

• devMode <boolean> - use this configuration option to enable development mode when you set its value to true. For more information, see devMode. For example:

devMode true

• rpcUsers <list> - use this configuration option to set the RPC users for the node. For more information, see rpcUsers. You can use arbitrary values in this configuration block - “incorrect” settings will not cause a DSL error. An example follows below:

rpcUsers = [[ user: "user1", "password": "test", "permissions": ["StartFlow.net.corda.flows.MyFlow"]]]

• configFile <string> - use this configuration option to generate an extended node configuration. For more information, see Node configuration. For example:

configFile = "samples/trader-demo/src/main/resources/node-b.conf"

• sshdPort <integer> - use this configuration option to specify the SSH port for the Docker container. This will be mapped to the same port on the host. If sshdPort is specified, then that port must be available on the host and not in use by some other service. If sshdPort is not specified, then a default value will be used for the SSH port on the container. Use the docker port <container_name> command to check which port has been allocated on the host for your container. For more information, see sshd. For example:

sshd {
  port = 2222
}

You can extend the deployNodes task with more node {} blocks to generate as many nodes as necessary for your application.

To extend node configuration beyond the properties defined in the deployNodes task, use the configFile property with the file path (relative or absolute) set to an additional configuration file. This file should follow the standard node configuration format of node.conf. The properties set there will be appended to the generated node configuration.

Alternatively, you can also add the path to the additional configuration file while running the gradle task via the -PconfigFile command-line option. However, this will result in the same configuration file being applied to all nodes.

Following on from the previous example, the PartyB node in the next example below has additional configuration options added from a file called none-b.conf:

task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
    [...]
    node {
        name "O=PartyB,L=New York,C=US"
        [...]
        // Grants user1 the ability to start the MyFlow flow.
        rpcUsers = [[ user: "user1", "password": "test", "permissions": ["StartFlow.net.corda.flows.MyFlow"]]]
        configFile = "samples/trader-demo/src/main/resources/node-b.conf"
    }
}

The drivers parameter in the node entry lists paths of the files to be copied to the drivers sub-directory of the node.

To add any drivers as dependencies of the cordaDriver configuration, use the following code (option recommended over using the drivers parameter):

dependencies {
    cordaDriver "net.corda:corda-shell:$corda_release_version"
    cordaDriver files('lib/my_specific_jar.jar')
}

The Cordform and Dockerform tasks copy the resolved contents of Gradle’s cordaDriver configuration into each node’s drivers directory before running the bootstrapper.

Package namespace ownership

To configure package namespace ownership, use the optional networkParameterOverrides and packageOwnership blocks, in a similar way to how the configuration file is used by the Network Bootstrapper tool. For example:

task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
    [...]
    networkParameterOverrides {
        packageOwnership {
            "com.mypackagename" {
                keystore = "_teststore"
                keystorePassword = "MyStorePassword"
                keystoreAlias = "MyKeyAlias"
            }
        }
    }
    [...]
}

Sign CorDapp JAR files

The default Cordform behaviour is to deploy CorDapp JAR files “as built”.

• Prior to Corda 4.0, all CorDapp JAR files were unsigned.
• As of Corda 4.0, CorDapp JAR files created by the gradle cordapp plug-in are signed by a Corda development certificate by default.

You can use the Cordform signing entry to override and customise the signing of CorDapp JAR files. Signing a CorDapp enables its contract classes to use signature constraints instead of other types of constraints, such as Contract Constraints.

The signing task may use an external keystore, or create a new one. You can use the following parameters in the signing entry:

• enabled - the control flag to enable the signing process. It is set to false by default. Set to true to enable signing.
• all - if set to true (default), all CorDapps inside the cordapp sub-directory will be signed. If set to false, only the generated CorDapp will be signed.
• options - any relevant parameters of SignJar ANT task and GenKey ANT task. By default the JAR file is signed by a Corda development key. You can specify the external keystore can be specified. The minimal list of required options is shown below. For other options, see SignJar task.
  • keystore - the path to the keystore file. The default setting is cordadevcakeys.jks. The keystore is shipped with the plug-in.
  • alias - the alias to sign under. The default value is cordaintermediateca.
  • storepass - the keystore password. The default value is cordacadevpass.
  • keypass - the private key password, if it is different from the keystore password. The default value is cordacadevkeypass.
  • storetype - the keystore type. The default value is JKS.
  • dname - the distinguished name for the entity. Only use this option when generateKeystore is set to true (see below).
  • keyalg - the method to use when generating a name-value pair. The default value is RSA because Corda does not support DSA. Only use this option when generateKeystore is set to true (see below).
• generateKeystore - the flag to generate a keystore. The default value is false. If set to true, an “ad hoc” keystore is created and its key is used instead of the default Corda development key or any external key. The same options to specify an external keystore are used to define the newly created keystore. In addition, dname and keyalg are required. Other options are described in GenKey task. If the existing keystore is already present, the task will reuse it. However if the file is inside the build directory, then it will be deleted when the gradle clean task is run.

The example below shows the minimal set of options required to create a dummy keystore:

task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
     signing {
        enabled true
        generateKeystore true
        all false
        options {
            keystore "./build/nodes/jarSignKeystore.p12"
            alias "cordapp-signer"
            storepass "secret1!"
            storetype "PKCS12"
            dname "OU=Dummy Cordapp Distributor, O=Corda, L=London, C=GB"
            keyalg "RSA"
        }
    }
    //...

Contracts classes from signed CorDapp JAR files are checked by signature constraints by default. You can force them to be checked by zone constraints by adding contract class names to the includeWhitelist entry - the list will generate an include_whitelist.txt file used internally by the Network Bootstrapper tool. Before you add includeWhitelist to the deployNodes task, see Contract Constraints to understand the implications of using different constraint types. The snippet below configures contracts classes from the Finance CorDapp to be verified using zone constraints instead of signature constraints:

task deployNodes(type: net.corda.plugins.Cordform, dependsOn: ['jar']) {
    includeWhitelist = [ "net.corda.finance.contracts.asset.Cash", "net.corda.finance.contracts.asset.CommercialPaper" ]
    //...

Optional migration step

If you are migrating your database schema from an older Corda version to Corda 4.9, you must add the following parameter to the node section in the build.gradle and set it to true, as follows:

        runSchemaMigration = true

This step runs the full schema migration process as the last step of the Cordform task, and leave the nodes ready to run.

Run the Cordform task

To create the nodes defined in the deployNodes task example above, run the following command in a command prompt or a terminal window, from the root of the project where the deployNodes task is defined:

• Linux/macOS: ./gradlew deployNodes
• Windows: gradlew.bat deployNodes

This command creates the nodes in the build/nodes directory. A node directory is generated for each node defined in the deployNodes task, plus a runnodes shell script (or a batch file on Windows) to run all the nodes at once for testing and development purposes. If you make any changes to your CorDapp source or deployNodes task, you will need to re-run the task to see the changes take effect.