lpdg-iomanager

An IOManager that saves the generated result to files, is able to use websockets to stream or let a client poll for data or just returns the value of the lpdgenerator.

Usage

First install lpdg-iomanager:

npm install lpdg-iomanager -s

const lpdgenerator = require('lpdgenerator');
const lpdgiomanager = require('lpdg-iomanager')

var generator = new lpdgenerator();
var manager = new lpdgiomanager();

manager.run(generator);

And then run the program with an input file as parameter:

node myprog <input-file>

Input

There is an example input file in the root.

Name | Description | Default --- | --- | --- time:interval | The interval at which the parkings get updated and the stream sends updates | 30 file:output | The output directory | "" file:output_meta_data | Bool to see if meta data should be put in the file | false file:extension | Defines the extension of the generated files | "" file:name_format | Defines the format of the output filenames. DEFAULT: city-YYYY-MM-DDThhmmss, UNIX: UNIX timestamp of beginning of interval. | "DEFAULT" file:split | If files of cities should be split, if false will ignore "time:time_per_file" | true io:mode | Mode can be FILE, STREAM, POLL or STRING. If something other then FILE is used, most "file:xxxxx" variables will be ignored | "FILE" io:port | Port at which the websockt is made | 8080

Websockets

When the "io:mode" is STREAM or POLL, the manager will create a websocket to send data over the network.

STREAM

When streaming, the IOManager will send data to subscribed clients every "time:interval" seconds. To subscribe, clients have to send a JSON object with following parameters:

Name | Description --- | --- type | Can have te value INFO (if we just want to get info on the cities and parkings), SUB (if we want to subscribe to a city) or UNSUB (if we want to unsubscribe from a city) city | If the type of the request is SUB or UNSUB this value should be the number of the city we want to (un)subscribe

Sample client

const WebSocket = require('ws');

const ws = new WebSocket('ws://localhost:8080');
 
ws.on('open', function open() {
  ws.send('{"type" : "SUB", "city":0}');
});
 
ws.on('message', function incoming(data) {
  console.log(data.toString());
});

POLL

When the mode is POLL, clients have to requist data every time they want to have an update. CLients should send a JSON object with following parameters:

Name | Description --- | --- type | Can have te value INFO (if we just want to get info on the cities and parkings), GET (if we want to get the parking data) city | If the type of the request is GET this value should be the number of the city we want time | If the type of the request is GET this value should be the begin value of the data

Sample client

const WebSocket = require('ws');

const ws = new WebSocket('ws://localhost:8080');
 
ws.on('open', function open() {
  ws.send('{"type" : "GET", "city":0, "time": "1970-01-01T00:00:00"}');
});
 
ws.on('message', function incoming(data) {
  console.log(data.toString());
});

FILE

File output will just output the result for every city in separate files.