Node.js Plugin

The Node.js plugin will allow you to execute Node.js code in Clarive and view its result.

What is Node.js?

Node.js is a platform built on Chrome's JavaScript runtime for easily building fast and scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive, real-time applications that run across distributed devices.

Requirements

To be able to use the plugin correctly, you must have Node.js installed on the server where you wish to run the code.

Installation

To install the plugin, place the cla-nodejs-plugin folder inside $CLARIVE_BASE/plugins directory in the Clarive instance.

Parameters

The service will execute the code you write in it on the server you specify. It will create a temporary file with the code which will be shipped to the specified server.

The parameters available for this service are:

• Server (variable name: server) - The GenericServer Resource where you wish to execute the code.
• User (user) - User which will be used to connect to the server.
• Node.js path (user) - Full path for Node.js launching script, including the file. If you leave it empty, the plugin will launch node as a system environment variable.
• Node.js parameters (user) - Additional flags for the Node.js command.
• Remote temporary path (user) - Temporary path to which the file with the code will be shipped.
• Node.js code editor (user) - Enter here the code you wish to execute.

Only Clarive EE

• Errors and output - These two fields deal with managing control errors. The options are:
  • Fail and output error - Search for configured error pattern in script output. If found, an error message is displayed in the monitor showing the match.
  • Warning and output warning - Search for configured warning pattern in script output. If found, an error message is displayed in the monitor showing the match.
  • Custom - If combo box errors is set to custom, a new form is displayed to define the behavior with these fields:
  • OK - Range of return code values for the script to have succeeded. No message will be displayed in the monitor.
  • Warning - Range of return code values to warn the user. A warning will be displayed in monitor.
  • Error - Range of return code values for the script to have failed. An error message will be displayed in the monitor.

How to use

In Clarive EE

You can find this service in the Rule Designer palette.

Op Name: Run Node.js Code

Example:

      Server: nodejs_server
      Node.js path: /sytem/node.sh
      Remote temporal path: /tmp
      Node.js code editor: console.log('This is a nodejs example'); 

In Clarive SE

Rulebook

If you want to use the plugin through the Rulebook, in any do block, use this ops as examples to configure the different parameters:

rule: NodeJS demo
do:
   - nodejs_script:
       server: nodejs_server   # Required. Use the mid set to the resource you created
       user: ${username}
       remote_temp_path: "/tmp" # Required
       nodejs_args: ["-d"]            
       code: |                  # Required
          console.log('This is a nodejs example');

Outputs

Success

The plugin will return all the console output you set in the Node.js code.

do:
    - myvar = nodejs_script:
       server: nodejs_server   # Required. Use the mid set to the resource you created
       user: "clarive_user"
       remote_temp_path: "/tmp"
       nodejs_args: ["-d"]            
       code: |                  # Required
          console.log('This is a nodejs example');
    - echo: ${myvar}

For this command the output will be similar to this one:

This is a nodejs example 

Possible configuration failures

Code failed

Error running remote script

Make sure that the option is available and you code is correct to be executed in NodeJS.

Variable required

Error in rulebook (compile): Required argument(s) missing for op "nodejs_script": "server"

Make sure you have all required variables defined.

Not allowed variable

Error in rulebook (compile): Argument `Code` not available for op "nodejs_script"

Make sure you are using the correct paramaters (make sure you are writing the variable names correctly).

More questions?

Feel free to join Clarive Community to resolve any of your doubts.