traffic_cameras.py

#!/usr/bin/env python3
# encoding: utf-8

# Camaras de trafico de la DGT (España) directamente desde datos Datex

import xmltodict
import requests
import base64
import json
from qgis.core import QgsProject, QgsFeature

__author__ = 'Fran Raga'
__version__ = 0.1
__date__ = '2018-07-29'
__updated__ = '2018-07-29'


PREDEFINED_LOCATIONS_URL = 'http://infocar.dgt.es/datex2/dgt/CCTVSiteTablePublication/all/content.xml'

settings = QSettings()

def CreateMarker(layer, lista_camaras):
    layer.startEditing()
    categorized = []
    for camara in lista_camaras:
        id = camara['@id']
        if id == "GUID_CAM_15":
            break
        version = camara['@version']
        identificacion = camara['_0:cctvCameraIdentification']
        tipo = camara['_0:cctvCameraType']
        lat = camara['_0:cctvCameraLocation']['_0:locationForDisplay']['_0:latitude']
        lon = camara['_0:cctvCameraLocation']['_0:locationForDisplay']['_0:longitude']
        url = camara['_0:cctvStillImageService']['_0:stillImageUrl']['_0:urlLinkAddress']
        feature = QgsFeature()
        p = QgsPointXY()
        p.set(float(lon), float(lat))
        geom = QgsGeometry.fromPointXY(p)
        feature.setGeometry(geom)
        feature.setAttributes(
            [id, version, identificacion, tipo, lon, lat, url])
        layer.addFeatures([feature])

        Common(layer, url, id, categorized)

    layer.commitChanges()
    layer.updateExtents()
    layer.triggerRepaint()


def UpdateMarkers():
    print ("Actualizando Camaras")
    categorized = []
    layer = QgsProject.instance().mapLayersByName("Camaras")[0]
    for feature in layer.getFeatures():
        url = feature["url"]
        id = feature["id"]
        Common(layer, url, id, categorized)
    layer.triggerRepaint()
    print ("Camaras Actualizadas")
    return


def Common(layer, url, value, categorized):
    svg = """<?xml version="1.0" encoding="UTF-8" standalone="no"?><svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><image xlink:href="data:image/jpeg;base64,{0}" height="320" width="420" /></svg>"""
    data = requests.get(url, stream=True).content
    b64response = base64.b64encode(data)
    newsvg = svg.format(b64response.decode("utf-8")).replace('\n', '')
    path = r"D:\temp\cam\{0}.svg".format(value)
    with open(path, 'w') as f:
        f.write(newsvg)

    svgStyle = {}

    svgStyle['name'] = path
    svgStyle['size'] = '30'
    sym_image = QgsSvgMarkerSymbolLayer.create(svgStyle)

    symbol = QgsSymbol.defaultSymbol(layer.geometryType())
    symbol.changeSymbolLayer(0, sym_image)
    new_category = QgsRendererCategory(str(value), symbol, str(value))
    categorized.append(new_category)
    renderer = QgsCategorizedSymbolRenderer("id", categorized)

    layer.setRenderer(renderer)
    return


def CreateCameras():
    data = requests.get(PREDEFINED_LOCATIONS_URL)
    xpars = xmltodict.parse(data.text)
    parse = json.dumps(xpars)
    resp_dict = json.loads(parse)
    lista_camaras = resp_dict['_0:d2LogicalModel']['_0:payloadPublication']['_0:genericPublicationExtension'][
        '_0:cctvSiteTablePublication']['_0:cctvCameraList']['_0:cctvCameraMetadataRecord']

    crs = QgsCoordinateReferenceSystem('EPSG:4326')
    uri = 'Point?crs=' + crs.authid() + '&'
    fields = ["id", "version", "identificacion", "tipo", "lat", "lon", "url"]
    fieldsdesc = ['field=' + f for f in fields]
    fieldsstring = '&'.join(fieldsdesc)
    uri += fieldsstring
    layer = QgsVectorLayer(uri, "Camaras", "memory")

    CreateMarker(layer, lista_camaras)

    prjSetting3 = settings.value('/Projections/defaultBehavior')
    settings.setValue('/Projections/defaultBehavior', '')
    QgsProject.instance().addMapLayer(layer, True)
    settings.setValue('/Projections/defaultBehavior', prjSetting3)