@informatiqal/qlik-sse NPM

qlik-sse

Continuing from where Miralem left off. The original repository can be found here

New User documentation here

@informatiqal/qlik-sse is an npm package that simplifies the creation of Qlik Server Side Extensions in nodejs.

Check out Server Side Extension for more info and how to get started from the Qlik side.

Breaking change

After migrating to grpc-js and protobuf.js there is a small (but breaking) change when creating instance of a message. Instead of .buffer property we now have to call .finish() method.

//Old syntax
const tableDescription = q.sse.TableDescription.encode({
  fields: [
    { name: "Dim", dataType: q.sse.DataType.STRING },
    { name: "Value", dataType: q.sse.DataType.NUMERIC },
  ],
}).buffer;

//New syntax
const tableDescription = q.sse.TableDescription.encode({
  fields: [
    { name: "Dim", dataType: q.sse.DataType.STRING },
    { name: "Value", dataType: q.sse.DataType.NUMERIC },
  ],
}).finish();

Getting started

Prerequisites

Before continuing, make sure you:

have Node.js >= v8.0.0 installed
can configure your Qlik installation

Usage

Start by installing @informatiqal/qlik-sse:

npm install @informatiqal/qlik-sse

Next, create a file foo.js:

import * as q from "@informatiqal/qlik-sse";
//or import { server, sse, sseServices } from "@informatiqal/qlik-sse";

// create an instance of the server
const s = q.server({
  identifier: "xxx",
  version: "0.1.0",
});

// register functions
s.addFunction(/* */);

// start the server
s.start({
  port: 50051,
  allowScript: true,
});

and then run it to start the SSE plugin server:

node foo.js

Configure the SSE in your Qlik installation by following these instructions

If you're running Qlik Sense Desktop (or Qlik Engine) locally, restart it after starting the SSE server to allow Qlik Engine to get the SSE plugin's capabilities.

Assuming you have named the plugin sse, you should now be able to use it's script functions in expressions:

sse.ScriptEval('return Math.random()*args[0]', sum(Sales));

You have now successfully created a Server Side Extension that can be used from within Qlik Sense or Qlik Core.

Take a look at some of the examples on how to add functionality to the SSE.

Events

The package expose event emitter that emits couple of events - info and error

import { server, emitter } from "@informatiqal/qlik-sse";

const s = server({
  identifier: "MySSE",
  version: "0.1.0",
});

emitter.on("info", (message) => {
  // do something with the info message
});

emitter.on("error", (message) => {
  // do something in case of error
});

TODO

Documentation
- API
- Explain function types SCALAR, AGGREGATION and TENSOR
- Table load
- Documentation review + dedicated help/documentation page
Examples
- How to use tensorflow with qix data
- Real use cases
  - linear regression
  - k-means
  - ...
- Full Qlik example
  - configuring Qlik Engine to use SSEPlugin
  - dockerized environment
  - loading data
  - expression calls
Features
- Script evaluation
- SSL communication (certificate usage)
- Error handling
Code
- Convert to ES6
- ~~Convert to TypeScript?~~ Just used JSDoc. No need to complicate things
- Build step