Hop Server

Hop Server is a lightweight server to run workflows and pipelines in the Remote Native run configuration. Additonally, Hop Server can also be accessed directly through a number of REST services and in combination with the Web Service metadata type.

Starting and Stopping Hop Server

General Use

Hop Server is available as a script in your Hop installation directory.

Run Hop Server without any parameters to display its usage options. On Windows, this is hop-server.bat, on Mac and Linux, run hop-server.sh.

Usage: hop-server <Interface address> <Port> [-h] [-p <arg>] [-s] [-u <arg>]
or
Usage: Hop Server <Configuration File>
Starts or stops the hopServer server.
     -h,--help               This help text
     -p,--password <arg>     The administrator password.  Required only if
                             stopping the Hop Server server.
     -s,--stop               Stop the running hopServer server.  This is only
                             allowed when using the hostname/port form of the
                             command.
     -u,--userName <arg>     The administrator user name.  Required only if
                             stopping the Hop Server server.
Example: hop-server.sh 127.0.0.1 8080
Example: hop-server.sh 192.168.1.221 8081
Example: hop-server.sh /foo/bar/hop-server-config.xml
Example: hop-server.sh http://www.example.com/hop-server-config.xml
Example: hop-server.sh 127.0.0.1 8080 -s -u cluster -p cluster

The available Hop Server options are:

Start Hop Server with command line parameters

Hop Server can be started with hostname or ip address and port number as unnamed arguments:

hop-server <Interface address> <Port> [-h] [-p <arg>] [-s] [-u <arg>]

Example startup commands are:

hop-server.sh 127.0.0.1 8080

hop-server.sh 192.168.1.221 8081

Start Hop Server with a configuration file

Specify the xml configuration file as the only argument:

hop-server <Configuration File>

The syntax of this configuration file is fairly simple:

<hop-server-config>
  <hop-server>
    <name>server-8181</name>
    <hostname>localhost</hostname>
    <port>8181</port>
  </hop-server>
  <!-- Join the web server thread and wait until it's finished.
       The default is true
  -->
  <joining>true</joining>
  <!-- The maximum number of log lines kept in memory by the server.
       The default is 0 which means: keep all lines
   -->
  <max_log_lines>0</max_log_lines>
  <!-- The time (in minutes) it takes for a log line to be cleaned up in memory.
       The default is 0 which means: never clean up log lines
  -->
  <max_log_timeout_minutes>1440</max_log_timeout_minutes>
  <!-- The time (in minutes) it takes for a pipeline or workflow execution to be removed from the server status.
       The default is 0 which means: never clean executions
  -->
  <object_timeout_minutes>1440</object_timeout_minutes>
  <!-- The folder to read metadata objects from so that web services and database connections for sequences can be found.
       The default is that no metadata is configured: remotely executed pipelines and workflows will have their own metadata.
  -->
  <metadata_folder></metadata_folder>
</hop-server-config>

Example startup commands with a configuration file are:

hop-server.sh /foo/bar/hop-server-config.xml

Or with a remote configuration file:

hop-server.sh http://www.example.com/hop-server-config.xml

Stopping Hop Server

In a testing setup where Hop Server was started from a terminal, the process can be terminated through CTRL-C.

In headless environments, the same hop-server command used to start the server can be used to stop it:

hop-server.sh 127.0.0.1 8080 -s -u cluster -p cluster

Verify startup

Starting a Hop Server on the local machine e.g. on port 8081 will only take 1 or 2 seconds.

The console output will look similar to what is listed below:

2020/06/20 18:35:12 - HopServer - Installing timer to purge stale objects after 1440 minutes.
2020/06/20 18:35:12 - HopServer - Created listener for webserver @ address : localhost:8081

Connect to the Hop Server UI

To connect to the previously started server, point your browser to [http://localhost:8081](http://localhost:8081).

You’ll be prompted for your username and password. The default is cluster for both the username and password. The defaults obviously should be changed in any environment that goes beyond a simple local developer setup.

For each of the options in the pipeline and workflow dialogs described below, select a pipeline and workflow from the list and select the desired option.

The header bar for workflows and pipelines is almost identical (from left to right).