fix optional data_url usage #119

	name: TestExamples

	on:
	push:
	branches:
	- main
	- develop
	workflow_dispatch:

	env:
	WORKING_DIR: ./examples/
	MAPPING_URL: 'https://github.com/Mat-O-Lab/MapToMethod/raw/main/examples/example-map.yaml'
	PARSER_PORT: 3001
	APP_MODE: "development"
	APP_PORT: 5003
	MAPPER_PORT: 4000
	CONVERTER_PORT: 5000
	SSL_VERIFY: False

	jobs:
	TestExamples:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0
	- name: run app
	run: \|
	docker-compose -f docker-compose.develop.yml up -d
	sleep 20
	docker ps -a
	- name: parse mapping to YARRRML parser
	working-directory: ${{env.WORKING_DIR}}
	continue-on-error: true
	run: \|
	curl -X POST "http://localhost:${{env.APP_PORT}}/api/yarrrmltorml" -H "accept: text/turtle" -H "accept: application/json" -H "Content-Type: application/json" -d "{\"mapping_url\":\"${{env.MAPPING_URL}}\"}" > example.rml
	- name: print logs
	if: always()
	run: \|
	docker-compose logs
	- name: join the method and the data meta graph
	working-directory: ${{env.WORKING_DIR}}
	run: \|
	RESULT="$(curl -X POST "http://localhost:${{env.APP_PORT}}/api/createrdf" -H "accept: application/json" -H "Content-Type: application/json" -d "{\"mapping_url\":\"${{env.MAPPING_URL}}\"}")"
	DATA="$(jq .graph <<< "$RESULT")"
	#remove quots
	echo -e "${DATA:1:-1}" > example.rdf
	#unescape quots
	sed -i 's/\\"/'\"'/g' example.rdf
	- name: Commit files # commit the output folder
	uses: EndBug/add-and-commit@v9
	with:
	message: 'updated example output'
	add: '. --force'
	cwd: './examples/'

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