qanary-helpers 0.1.0

A package that helps to build components for the Qanary Framework

Qanary Helpers library

Qanary Helpers implements registration and querying functionality for the Qanary framework.

This library is used within a Python Qanary Component.

Install

Via PIP

pip install qanary_helpers

Latest version from GitHub

git clone https://github.com/Perevalov/qanary_helpers.git
cd qanary_helpers
pip install .

Usage

For the "Hello world example" create a file named component.py in your working directory. Then, fill the file with the following code (pay attention to the TODO comments):

import os
from datetime import datetime
from flask import Flask, request, jsonify
from qanary_helpers.registration import Registration
from qanary_helpers.registrator import Registrator
from qanary_helpers.qanary_queries import insert_into_triplestore, get_text_question_in_graph

# TODO: may be changed to other config type (e.g. parsing a json file)
SPRING_BOOT_ADMIN_URL = os.environ['SPRING_BOOT_ADMIN_URL']    
SPRING_BOOT_ADMIN_USERNAME = os.environ['SPRING_BOOT_ADMIN_USERNAME']
SPRING_BOOT_ADMIN_PASSWORD = os.environ['SPRING_BOOT_ADMIN_PASSWORD']
SERVICE_HOST = os.environ['SERVICE_HOST']
SERVICE_PORT = os.environ['SERVICE_PORT']
SERVICE_NAME_COMPONENT = os.environ['SERVICE_NAME_COMPONENT']
SERVICE_DESCRIPTION_COMPONENT = os.environ['SERVICE_DESCRIPTION_COMPONENT']
URL_COMPONENT = f"http://{SERVICE_HOST}:{SERVICE_PORT}"

app = Flask(__name__)


@app.route("/annotatequestion", methods=["POST"])
def qanary_service():
    triplestore_endpoint_url = request.json["values"]["urn:qanary#endpoint"]
    triplestore_ingraph_uuid = request.json["values"]["urn:qanary#inGraph"]
    
    question_text = get_text_question_in_graph(triplestore_endpoint_url, triplestore_ingraph_uuid)

    # Start TODO: configure your business logic here and adjust the sparql query
    result = "Hello World"

    SPARQLquery = """
                    PREFIX qa: <http://www.wdaqua.eu/qa#>
                    PREFIX oa: <http://www.w3.org/ns/openannotation/core/>
                    PREFIX dbo: <http://dbpedia.org/ontology/>
                    INSERT {{
                    GRAPH <{uuid}> {{
                        ?a oa:annotationText "{annotation_text}" .
                        ?a oa:annotatedBy <urn:qanary:{component}> .
                        ?a oa:annotatedAt ?time .
                        }}
                    }}
                    WHERE {{
                        BIND (IRI(str(RAND())) AS ?a) .
                        BIND (now() as ?time) 
                    }}
                """.format(
                    uuid=triplestore_ingraph_uuid,
                    component=SERVICE_NAME_COMPONENT.replace(" ", "-"),
                    annotation_text=result)

    insert_into_triplestore(triplestore_endpoint_url,
                            SPARQLquery)  # inserting new data to the triplestore
    # End TODO

    return jsonify(request.get_json())


@app.route("/health", methods=["GET"])
def health():
    return "alive"


if __name__ == "__main__":
    metadata = {
        "start": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
        "description": SERVICE_DESCRIPTION_COMPONENT,
        "written in": "Python"
    }

    registration = Registration(
        name=SERVICE_NAME_COMPONENT,
        serviceUrl=f"{URL_COMPONENT}",
        healthUrl=f"{URL_COMPONENT}/health",
        metadata=metadata
    )

    reg_thread = Registrator(SPRING_BOOT_ADMIN_URL, SPRING_BOOT_ADMIN_USERNAME,
                            SPRING_BOOT_ADMIN_PASSWORD, registration)
    reg_thread.setDaemon(True)
    reg_thread.start()

    app.run(host='0.0.0.0', port=SERVICE_PORT, debug=True)

As you may see, several environment variables has to be set before the script execution:

• SPRING_BOOT_ADMIN_URL -- URL of the Qanary pipeline (see Step 1 and Step 2 of the tutorial)
• SPRING_BOOT_ADMIN_USERNAME -- the admin username of the Qanary pipeline
• SPRING_BOOT_ADMIN_PASSWORD -- the admin password of the Qanary pipeline
• SERVICE_HOST -- the host of your component without protocol prefix (e.g. http://). It has to be visible to the Qanary pipeline
• SERVICE_PORT -- the port of your component (has to be visible to the Qanary pipeline)
• SERVICE_NAME_COMPONENT -- the name of your component
• SERVICE_DESCRIPTION_COMPONENT -- the description of your component

You may also change the configuration via environment variables to any configuration that you want (e.g. via a json file).

To run the component, simply execute python component.py in your terminal. If the component registration was successful, a corresponding message will appear in the output.