How to get the geometry of a point from the latitude and longitude coordinates of an API in JSON format

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I'm trying to use data from an API in json format in my QGIS project. To do so, I call the link in this way.

I would like to get the attributes and also the latitude and longitude coordinates from the JSON to create the geometry in QGIS. Is this possible according to you? And how could i include the query in my loop to get the coordinate and create points of data ?

Here is what the current JSON looks like :

    {
  "nhits": 49,
  "parameters": {
    "dataset": "evenements-publics-cibul",
    "timezone": "UTC",
    "rows": 1354,
    "start": 0,
    "format": "json",
    "facet": [
      "tags",
      "placename",
      "department",
      "region",
      "city",
      "date_start",
      "date_end",
      "pricing_info",
      "updated_at",
      "city_district"
    ]
  },
  "records": [
    {
      "datasetid": "evenements-publics-cibul",
      "recordid": "41ca897b543df849ceb4a1c43fd4d11daeb251eb",
      "fields": {
        "uid": "99319396",
        "image": "http://cibul.s3.amazonaws.com/event_port-des-champs-elysees-tuileries_722620.jpg",
        "updated_at": "2016-06-19T18:53:27+00:00",
        "free_text": "## 18h30\u00a0: \u00a0PARISANDES - Musique des Andes \u00a0\n\n## 20h\u00a0: LE PLOUM \u2013 Jazz \u00a0\n\n## 21h30\u00a0: JOYLINER - Rock\n\n## 23h\u00a0:\u00a0ROUND WINDOW & 26$ IN MY HAND \u2013 Jazz & Rock \u00a0\n\n## Association ADNI\n\n## Port des Champs Elys\u00e9es - 75008 Paris\n\n## P\u00e9niche ARBOIS : rive droite - passerelle Solf\u00e9rino\u00a0\n\n## M\u00e9tro : Concorde ou Solf\u00e9rino",
        "latlon": [
          48.861288,
          2.329838
        ],
        "city": "Paris",
        "title": "Port Des Champs Elys\u00e9es - Tuileries",
        "pricing_info": "Gratuit - Ext\u00e9rieur",
        "date_start": "2016-06-21",
        "department": "Paris",
        "image_thumb": "http://cibul.s3.amazonaws.com/evtbevent_port-des-champs-elysees-tuileries_722620.jpg",
        "date_end": "2016-06-21",
        "description": "Concerts Gratuits - P\u00e9niche ARBOIS - Jazz, Rock, Musique des Andes",
        "tags": "rock,jazz,gratuit,concert,andes,musique,p\u00e9niche,quais,seine",
        "space_time_info": "Port des Champs Elys\u00e9es - Quai des Tuileries, le mardi 21 juin \u00e0 18:30",
        "timetable": "2016-06-21T18:30:00 2016-06-21T00:00:00",
        "link": "http://openagenda.com/event/port-des-champs-elysees-tuileries",
        "address": "PORT DES TUILERIES",
        "lang": "fr",
        "placename": "Port des Champs Elys\u00e9es - Quai des Tuileries",
        "region": "\u00cele-de-France",
        "program_uid": "7633600 64984403 63658282 59310395 31778250"
      },
      "geometry": {
        "type": "Point",
        "coordinates": [
          2.329838,
          48.861288
        ]
      },
      "record_timestamp": "2017-03-29T15:13:50.163000+00:00"
    },

Thank you,

Wendy

qgis api python
1 Answers

I wrote this script which reads the json file recursively and outputs a vector layer with all the attributes and geometries. You can output all supported file types listed here: Vector drivers

Paste this code in the QGIS python console as a new script. Remember to set the input JSON file path, the output vector layer path with the file extension and the CRS code.

import json

'''put inside the quotes your json file path'''
json_file_path = ''

'''put inside the quotes where the vector layer will be saved,
if not specified vector layer will be saved as a temporal layer'''
vector_layer_path = ''

vector_crs = 'EPSG:4326' # set here your crs

def scanDict(d):
    for d_key in d.keys():
        if type(d[d_key]) == dict:
            for entry in scanDict(d[d_key]):
                yield entry
        else:
            yield [d_key, d[d_key]]
            
json_file = json.load(open(json_file_path, 'r'))
records = json_file['records']
project = QgsProject().instance()
fields = list(dict(scanDict(records[0])).keys())
vector_layer = QgsVectorLayer(f"Point?crs={vector_crs}", "Points", "memory")
vector_layer.startEditing()
for field_name in fields:
    q_field = QgsField(field_name, QVariant.String)
    vector_layer.addAttribute(q_field)
    vector_layer.commitChanges(stopEditing=False)
for record in records:
    record_values = dict(scanDict(record))
    x = record_values['coordinates'][0]
    y = record_values['coordinates'][1]
    feature = QgsFeature()
    feature.setGeometry(QgsGeometry().fromPointXY(QgsPointXY(x, y)))
    feature.setAttributes([str(item) for item in list(record_values.values())])
    vector_layer.addFeature(feature)
vector_layer.commitChanges()
save_options = QgsVectorFileWriter.SaveVectorOptions()
save_options.driverName = "ESRI Shapefile"
save_options.fileEncoding = "UTF-8"
transform_context = project.transformContext()

if len(vector_layer_path):
    error = QgsVectorFileWriter.writeAsVectorFormatV2(vector_layer, vector_layer_path, transform_context, save_options)
    if error[0] == QgsVectorFileWriter.NoError:
        print("file saved succesfull")
    else:
        print(error)
    project.addMapLayer(QgsVectorLayer(vector_layer_path, 'Points', 'ogr'))
else:
    project.addMapLayer(vector_layer)
Admin1
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