csw-host-config

This is just a helper to create a host configuration application. A component/subsystem developer can create a custom host configuration application using this helper. To be more precise, every Github repository should have one host configuration application. The reason for having one application per repo is that it will have all the required dependencies and can be deployed independently on any machine.

This application will start multiple containers on a given host machine and each container will have single/multiple components.

How to create

Scala

copysourceobject HostConfigApp extends App {

  HostConfig.start("HostConfigApp", CSW, args)

}

Java

copysourcepublic class JHostConfigApp {

    public static void main(String[] args) {
        JHostConfig.start("JHost-Config-App", JSubsystem.CSW, args);
    }

}

Command line parameter options

• --local is an optional parameter. When supplied, get the host configuration file from local machine located at hostConfigPath, otherwise, fetch it from the Config Service
• <file> is a mandatory parameter. It specifies Host configuration file path
• -s, --container-script <script-path> specifies the path of the generated shell script for the container command app from task universal:packageBin (sbt-native-packager task)
• --help prints the help of the application.
• --version prints the version of the application.

Examples

Pre-requisites

• Run sbt project/universal:packageBin command. Here, the project contains HostConfigApp and ContainerCmdApp and it depends on the required components. Ex. Hcd’s, Assembly’s etc.
• Navigate to project/target/universal directory
• Unzip the file created with the project’s name
• Navigate to the bin directory from the unzipped contents

The sbt task: sbt project/universal:packageBin creates the following four scripts in the bin directory:

• trombone-host-config-app : Responsible for starting multiple containers. It takes a hostconfig.conf file as an argument which contains the list of container specifications.
• trombone-container-cmd-app : Responsible for starting a single container or component in standalone mode. It takes a containerConfig.conf file as an argument which contains single container specifications.
• trombone-host-config-app.bat : For Windows machine.
• trombone-container-cmd-app.bat : For Windows machine.

Examples:

1. ./trombone-host-config-app hostconfig.conf -s ./trombone-container-cmd-app
   

   Fetch hostconfig.conf from the Configuration Service which contains a multiple container configuration, then invoke the trombone-container-cmd-app script per the container configuration which spawns the container

2. ./trombone-host-config-app --local hostconfig.conf -s ./trombone-container-cmd-app
   

   Fetch and parse hostconfig.conf from the current directory which contains a multiple container configuration, then invoke the trombone-container-cmd-app script per the container configuration which spawns the container

Where does it fit in overall deployment strategy (may change)

Custom Host Configuration

hostconfig.conf

copysource# This is a host configuration file which contains list of containers to be spawned by host configuration app
containers: [
  {
    # path of individual container configuration file
    configFilePath: "/Users/salonivithalani/Desktop/tw_tmt/csw/examples/src/main/resources/assemblyContainer.conf"
    # provide 'Remote' if file needs to fetched from config service else
    # provide 'Local' to fetch file from local machine
    configFileLocation: "Local"
  },
  {
    configFilePath: "/Users/salonivithalani/Desktop/tw_tmt/csw/examples/src/main/resources/hcdStandalone.conf"
    configFileLocation: "Local"
  }
]

Help

Use the following command to get help on the options available with this app

./bin/trombone-host-config-app --help

Version

Use the following command to get version information for this app

./bin/trombone-host-config-app --version

Systemd configuration

Using systemd, you can configure a host configuration application to spawn containers on a machine to be run automatically on system startup.

For detailed information on systemd configuration, please refer to readme.md