actor-init-ldes-client

Table of contents

1. actor-init-ldes-client
   1. Setup
   2. Use locally
   3. Use context
   4. Save result

The actor-init-ldes-client can be used to harvest the published eventstreams via the command line interface (CLI) or can be setup within an application. Full documentation on the actor-init-ldes-client can be found here.

Setup

Make sure you have Node.js installed. Open the Node.js command prompt. Install the actor-init-ldes-client npm package:

npm install -g @treecg/actor-init-ldes-client

Run your command in the Node.js command prompt to harvest a certain event stream

for example

actor-init-ldes-client  https://apidg.gent.be/opendata/adlib2eventstream/v1/hva/objecten

The links to the event streams can be found here

It is possible to add multiple parameters to your command:

Parameter	Description	Possible values
pollingInterval	Number of milliseconds before refetching uncacheable fragments	for example: 5000
mimeType	the MIME type of the output	application/ld+json, text/turtle…
context	path to a file with the JSON-LD context you want to use when MIME type is application/ld+json	for example: ./context.jsonld
fromTime	datetime to prune relations that have a lower datetime value	for example: 2020-01-01T00:00:00
emitMemberOnce	whether to emit a member only once, because collection contains immutable version objects.	true / false
disableSynchronization	whether to disable synchronization or not (by default set to “false”, syncing is enabled)	true / false
disableFraming	whether to disable JSON-LD framing when mimeType is ‘application/ld+json’ or when representation is ‘Object’ (by default set to “false”). Value can be set to “true” or “false”	true / false
dereferenceMembers	whether to dereference members, because the collection pages do not contain all information (by default: false).	true / false
requestsPerMinute	how many requests per minutes may be sent to the same host (optional)	any number
loggingLevel	The detail level of logging; useful for debugging problems. (default: info)	‘error’, ‘warn’, ‘info’, ‘verbose’, ‘debug’, ‘silly’
processedURIsCount	The maximum number of processed URIs (members and fragments) that remain in the cache. (default: 10000)	any number

for example

actor-init-ldes-client --pollingInterval 5000 --mimeType application/ld+json --context context.jsonld --fromTime 2021-02-03T15:48:12.309Z --emitMemberOnce true --disablePolling true https://apidg.gent.be/opendata/adlib2eventstream/v1/dmg/objecten

Use locally

Install the npm package on the location where you want to run the script. Copy the commmand line below in the CLI;

npm install -g @treecg/actor-init-ldes-client

In order to use it as a library, you can leave out the -g.

Use context

By making use of following contextfile, the harvested results will be structured using OSLO.

Save the context (from the code below) locally.

{   "@context": [
                "https://apidg.gent.be/opendata/adlib2eventstream/v1/context/cultureel-erfgoed-object-ap.jsonld",
		        "https://apidg.gent.be/opendata/adlib2eventstream/v1/context/persoon-basis.jsonld",
		        "https://apidg.gent.be/opendata/adlib2eventstream/v1/context/cultureel-erfgoed-event-ap.jsonld",
		        "https://apidg.gent.be/opendata/adlib2eventstream/v1/context/organisatie-basis.jsonld",
      {
          "dcterms:isVersionOf": {
              "@type": "@id"
          },
          "prov": "http://www.w3.org/ns/prov#",
          "skos": "http://www.w3.org/2004/02/skos/core#",
          "label": "http://www.w3.org/2000/01/rdf-schema#label",
          "opmerking": "http://www.w3.org/2004/02/skos/core#note",

          "cest": "https://www.projectcest.be/wiki/Publicatie:Invulboek_objecten/Veld/"
      }
  ]
}

Save result

To save the result add following line at the end of your command:

> PATH_TO_DIRECTORY\output.json

A json file (output.json) will be saved in the directory of your choice.