See example of the usage of Python for developing MicroService and make it accessible from Proc.Logic /IoT app: https://www.snap4city.org/645
See also Python usage of API: https://www.snap4city.org/829
get token in Python
import requests
# this is only an example do not use in production,
# consider that each call it will create a new session on keycloak for each request,
# the token should be reused until it is expired and when expired it can be 'refreshed' using the refresh token
def getTokenViaUserCredentials(username,password):
payload = {
'f': 'json',
'client_id': xxxxx-tool',
'grant_type': 'password',
'username': username,
'password': password
}
header = {
'Content-Type': 'application/x-www-form-urlencoded'
}
urlToken = "https://www.snap4city.org/auth/realms/master/protocol/openid-connect/token"
response = requests.request("POST", urlToken, data=payload, headers=header)
token = response.json()
return token
def getTokenViaRefreshToken(old_token):
if not 'refresh_token' in old_token:
return None
payload = {
'f': 'json',
'client_id': xxxxx-tool',
'grant_type': 'refresh_token',
'refresh_token': old_token['refresh_token']
}
header = {
'Content-Type': 'application/x-www-form-urlencoded'
}
urlToken = "https://www.snap4city.org/auth/realms/master/protocol/openid-connect/token"
response = requests.request("POST", urlToken, data=payload, headers=header)
token = response.json()
return token
Access data via Smart City API: get historical and last data via ServiceURI, in Python
#get the token of the user
token = getTokenViaUserCredentials ('…user…','…password…')
print('token', token)
if 'access_token' in token :
head = {
"Content-Type": "application/json",
"Authorization": f"Bearer {token['access_token']}"
}
api_url ="https://<xxxxx>/ServiceMap/api/v1/"
service_uri = "http://www.disit.org/km4city/resource/iot/<xxxxx>/<xxxxx>/ccccc_Device_01"
response = requests.request("GET", api_url + "?serviceUri=" + service_uri +"&fromTime=60-day", headers=head)
print(response.json())
else:
print('failed getting access token', token)
Send data on platform, via Broker: send/update values of a device, in Python
if 'access_token' in token :
head = {
"Content-Type": "application/json",
"Authorization": f"Bearer {token['access_token']}"
}
api_url = "https://iot-app.snap4city.org/orion-broker-<xxxxx>/v2/"
device_id = "ccccc_Device_01"
payload = {
"dateObserved": {
"value": "2023-01-27T01:01:02.000Z",
"type": "string"
},
"FatigueValue": {
"value": 13.1,
"type": "number"
}
}
response = requests.request("PATCH", api_url + "entities/" + device_id +"/attrs?type=Sensor&elementid=" + device_id, json=payload, headers=head)
if response.status_code!=204 :
print(response.json())
else:
print(device_id+" updated!")
else:
print('failed getting access token', token)
