// Numbas version: exam_results_page_options
{"name": "Fetch data from an external source before variable generation", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Fetch data from an external source before variable generation", "tags": [], "metadata": {"description": "<p>This question shows how to use the question's JavaScript preamble to request data from an external source, and use that data in question variables.</p>\n<p>Note that this means the question only works when the external source is available. Use this very carefully, and avoid it if you possibly can!</p>", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "<p>The preamble of this question calls <a href=\"https://fakerapi.it/api/v1/books?_quantity=1\">https://fakerapi.it/api/v1/books?_quantity=1</a> to get information about a randomly generated fake book. This particular task could be done entirely in Numbas, but it demonstrates the principle of requesting data from an external source.</p>\n<p>If the request succeeds, then the variable <code>book</code> is set with the returned data. The variables <code>title</code> and <code>author</code> are both defined to extract information from book.</p>", "advice": "", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"author": {"name": "author", "group": "Ungrouped variables", "definition": "book['author']", "description": "", "templateType": "anything", "can_override": false}, "title": {"name": "title", "group": "Ungrouped variables", "definition": "book['title']", "description": "", "templateType": "anything", "can_override": false}, "book": {"name": "book", "group": "Ungrouped variables", "definition": "json_decode(safe(\"{\\n  \\\"id\\\": 1,\\n  \\\"title\\\": \\\"Dormouse, not.\\\",\\n  \\\"author\\\": \\\"Rosalyn Kub\\\",\\n  \\\"genre\\\": \\\"Et\\\",\\n  \\\"description\\\": \\\"Mock Turtle, and said to the croquet-ground. The other guests had taken his watch out of their hearing her; and when she next peeped out the answer to shillings and pence. \\'Take off your hat,\\' the.\\\",\\n  \\\"isbn\\\": \\\"9788125034827\\\",\\n  \\\"image\\\": \\\"http://placeimg.com/480/640/any\\\",\\n  \\\"published\\\": \\\"1998-04-11\\\",\\n  \\\"publisher\\\": \\\"Laudantium Sit\\\"\\n}\"))", "description": "<p>The data about the book is stored in this variable once it's received from the external API. A default value is given so that the editor doesn't complain about an undefined variable, and to document the variable's structure.</p>", "templateType": "json", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["book", "author", "title"], "variable_groups": [], "functions": {}, "preamble": {"js": "const url = 'https://fakerapi.it/api/v1/books?_quantity=1';\nreturn fetch(url, {headers: {'Accept': 'application/json'}}).then(response => {\n  return response.json().then(({data}) => {\n    const [book] = data;\n    question.scope.setVariable('book', Numbas.jme.wrapValue(book));\n  })\n});", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p>This question is about the book <strong>\"{title}\"</strong> by {author}.</p>"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}]}], "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}