Commands

hop-client provides a command line interface for various tasks:

  • hop configure: Authentication utilities

  • hop publish: Publish messages such as GCN circulars and notices

  • hop subscribe: Listen to messages such as GCN circulars and notices

  • hop version: Show version dependencies of hop-client

hop configure

This command allows a user to handle auth-based configuration.

usage: hop configure [-h] <command> ...

Configuration utilities.

optional arguments:
  -h, --help          show this help message and exit

commands:
    locate            display configuration path
    setup             set up configuration

hop publish

This command allows a user to publish various structured and unstructured messages, including:

Structured messages such as GCN circulars and VOEvents are published as JSON-formatted text.

usage: hop publish [-h] [--no-auth] [-f {VOEVENT,CIRCULAR,BLOB}]
                   URL [MESSAGE [MESSAGE ...]]

Publish messages.

positional arguments:
  URL                   Sets the URL (kafka://host[:port]/topic) to publish
                        messages to.
  MESSAGE               Messages to publish.

optional arguments:
  -h, --help            show this help message and exit
  --no-auth             If set, disable authentication.
  -f {VOEVENT,CIRCULAR,BLOB}, --format {VOEVENT,CIRCULAR,BLOB}
                        Specify the message format. Defaults to BLOB for an
                        unstructured message.

hop subscribe

This command allows a user to subscribe to messages and print them to stdout.

usage: hop subscribe [-h] [--no-auth] [-s {EARLIEST,LATEST}] [-p] [-j] URL

Subscribe to messages.

positional arguments:
  URL                   Sets the URL (kafka://host[:port]/topic) to publish
                        messages to.

optional arguments:
  -h, --help            show this help message and exit
  --no-auth             If set, disable authentication.
  -s {EARLIEST,LATEST}, --start-at {EARLIEST,LATEST}
                        Set the message offset offset to start at. Default:
                        LATEST.
  -p, --persist         If set, persist or listen to messages indefinitely.
                        Otherwise, will stop listening when EOS is received.
  -j, --json            Request message output as raw json

hop version

This command prints all the versions of the dependencies

usage: hop version [-h]

List all the dependencies' versions.

optional arguments:
  -h, --help  show this help message and exit