README.md

README

This component generates Kafka streams of rasterdata, which can be used to test the integration of rasterdata processing in StreamPipes.

See BigGIS for the big picture.

This component provides two data streams, which send rasterdata tiles in different formats.

• inline

  contains the rasterdata serialized in the Kafka message. As the Kafka message contains JSON content, the binary data is Base64-encoded.

• out-of-band

  contains an HTTP URI for the raster data. This component contains the necessary HTTP server to serve the files.

Installation

Add following fragment to your StreamPipes' docker-compose.yml:

rasterdata-source:
  image: laus.fzi.de:8201/biggisstreampipes/rasterdata-source
  depends_on:
    - "kafka"
  environment:
    JAVA_OPTS: "-Dkafka.server=kafka:9092"
  ports:
    - "8321:9000"
  volumes:
    - "./data/tiles:/tiles"
  networks:
    spnet:

You also need the Rasterdata Adapter to provide Streampipes with the metadata of this component.

Usage

Both streams don't send continuously, but only when triggered externally. The triggering is done by a HTTP Post request.

curl -H "application/json" -d $jsonString http://$dockerHost:8321/start-source

The JSON document takes the following fields (the displayed values are the defaults used if no value is given).

{
 "startIndex": 1,
 "endIndex": 5,
 "interval": 3,
 "tileset": "techpark",
 "serializer": "json-inline"
}"

startIndex and endIndex limit the range of tiles sent. interval is the sending interval in seconds. tileset names the tileset used. Custom tilesets can be added, see below. serializer is either json-inline or or json-oob.

Adding Tilesets

A tileset is just a sequence of image files, which are served in alphabetical order. If you limit the range served with startIndex and/or endIndex, the values reference this order, so for best user experience, name your files with a common prefix and a zero-padded number.

Put all tile files in one common directory und put it in your tiles docker volume (data/tiles in the fragment above). Use the name of the directory as parameter tileset in your JSON request.