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Running the Stream Processor

Run and manage Stream Processor images individually, or as part of a group

Simple example Docker workflow

Simple example Kubernetes workflow

For clarity in the examples below, environment variables are used to configure the pipelines; a config.yaml file could be used as well.

Setup

Working from the following project directory:

$ ls
spec.q

With the following spec.q:

cat spec.q
.qsp.run
  .qsp.read.fromCallback[`upd]
  .qsp.window.timer[00:00:05]
  .qsp.write.toConsole[]

Running in Kubernetes

To deploy and run in Kubernetes using the provided Coordinator service, follow the Kubernetes configuration and deployment instructions for launching the Coordinator within the cluster. The instructions also detail how to deploy and teardown a pipeline once the Coordinator service has started.

Running in Docker Compose

The above examples can be run in Docker Compose with an appropriate Docker Compose file (docker-compose.yaml).

Configuration to add Service Discovery or Monitoring

docker-compose.yaml example:

version: "3.3"
services:
  controller:
    image: portal.dl.kx.com/kxi-sp-controller:1.10.0
    ports:
      - 6000:6000
    environment:
      - KDB_LICENSE_B64
    command: ["-p", "6000"]
    deploy:
      restart_policy:
        condition: on-failure

  worker:
    image: portal.dl.kx.com/kxi-sp-worker:1.10.0
    ports:
      - 5000
    environment:
      - KDB_LICENSE_B64
      - KXI_SP_SPEC=/app/spec.q
      - KXI_SP_PARENT_HOST=controller:6000
    volumes:
      - .:/app
    command: ["-p", "5000"]
    deploy:
      restart_policy:
        condition: on-failure
    depends_on:
      - controller

With this Docker Compose file, the Controller and Worker can be created at once with:

docker-compose up

Multiple Workers in Docker Compose

First, create a YAML file called templates.yaml containing all common configuration for each Worker service:

services:
  worker_common:
    image: portal.dl.kx.com/kxi-sp-worker:1.10.0
    ports:
      - 5000
    environment:
      - KDB_LICENSE_B64
      - KXI_SP_SPEC=/app/spec.q
      - KXI_SP_PARENT_HOST=controller:6000
    volumes:
      - .:/app
    command: ["-p", "5000"]
    deploy:
      restart_policy:
        condition: on-failure

Now, we can easily create multiple Worker services in docker-compose.yaml, each with a unique ordinal:

version: "3.3"
services:
  controller:
    image: portal.dl.kx.com/kxi-sp-controller:1.10.0
    ports:
      - 6000:6000
    environment:
      - KDB_LICENSE_B64
      - KXI_SP_MIN_WORKERS=3
    command: ["-p", "6000"]
    deploy:
      restart_policy:
        condition: on-failure

  worker_1:
    extends:
      file: templates.yaml
      service: worker_common
    environment:
      - KXI_SP_ORDINAL=1
    depends_on:
      - controller

  worker_2:
    extends:
      file: templates.yaml
      service: worker_common
    environment:
      - KXI_SP_ORDINAL=2
    depends_on:
      - controller

  worker_3:
    extends:
      file: templates.yaml
      service: worker_common
    environment:
      - KXI_SP_ORDINAL=3
    depends_on:
      - controller

Notice that we have added a new environment variable to the Controller, KXI_SP_MIN_WORKERS. This designates how many Workers the Controller will wait for before starting all registered Workers. Also of note is the KXI_SP_ORDINAL environment variable for each Worker. This ordinal must be set to a unique integer for each Worker when using multiple Workers with the same Controller. See Environment Variables for more information about configuring Workers and Controllers with environment variables.

Running separate containers

Running with one Worker

First, create a kx network and a Controller to orchestrate and manage the pipeline.

docker network create kx
docker run -it -p 6000:6000 \
    --network=kx \
    -e "KDB_LICENSE_B64=$KDB_LICENSE_B64" \     # Set the kdb+ license to use
    --restart unless-stopped \                  # Restart the Controller if it dies
    portal.dl.kx.com/kxi-sp-controller:1.10.0 -p 6000

A Controller then needs Workers to orchestrate. We need to know the hostname of the Controller.

docker ps
CONTAINER ID   IMAGE                   .. PORTS                                       NAMES
0d05f4679db2   kxi-sp-controller:1.10.0 .. 0.0.0.0:6000->6000/tcp, :::6000->6000/tcp   cranky_mclaren

Note the container ID of the Controller, and change the KXI_SP_PARENT_HOST below to the container ID output from that command.

Bind in the project directory to make the spec available.

A Worker can be created with:

docker run -it -p 5000:5000 \
    --network=kx \
    -v "$(pwd)":/app \                           # Bind in the project directory
    -e KXI_SP_SPEC="/app/spec.q" \               # Point to the bound spec file
    -e KXI_SP_PARENT_HOST="0d05f4679db2:6000" \  # Point Worker to its Controller
    -e "KDB_LICENSE_B64=$KDB_LICENSE_B64" \      # Set the kdb+ license to use
    --restart unless-stopped \                   # Restart the Worker if it dies
    portal.dl.kx.com/kxi-sp-worker:1.10.0 -p 5000

Set the kdb+ license

Running with multiple Workers

Rather than running the pipeline with a single Worker, some pipelines (such as those reading from Kafka or callback functions) can be parallelized by orchestrating multiple Workers.

To do this, start a new Controller with a greater number of required Workers:

$ docker run -it -p 6000:6000 \
    --network=kx \
    -e "KDB_LICENSE_B64=$KDB_LICENSE_B64" \
    -e KXI_SP_MIN_WORKERS=3 \                   # Set this pipeline to use 3 Workers
    --restart unless-stopped \
    portal.dl.kx.com/kxi-sp-controller:1.10.0 -p 6000

Then launch the required number of Workers. Here we use a loop to set each to a known port.

Change KXI_SP_PARENT_HOST to the new Controller’s container ID.

for port in 5001 5002 5003;
do
    docker run -it -p $port:5000 \
        --network=kx \
        -v "$(pwd)":/app \
        -e KXI_SP_SPEC="/app/spec.q" \
        -e KXI_SP_PARENT_HOST="0d05f4679db2:6000" \
        -e "KDB_LICENSE_B64=$KDB_LICENSE_B64" \
        portal.dl.kx.com/kxi-sp-worker:1.10.0 -p 5000
done

There will now be three Workers up and running, on ports 5001, 5002, and 5003.