Files
notifications-api/app/clients/cbc_proxy.py
David McDonald 2aad3163e6 Allow CBC proxy client to take channel
This moves the hardcoding to test channels one step up to where we call
`create_and_send_broadcast`

We can then after this, start to differ whether we give it the 'test' or
'severe' channel based on the services channel setting.
2021-02-01 14:10:38 +00:00

420 lines
12 KiB
Python

import json
from abc import ABC, abstractmethod
import boto3
from flask import current_app
from notifications_utils.template import non_gsm_characters
from app.config import BroadcastProvider
from app.utils import DATETIME_FORMAT, format_sequential_number
# The variable names in this file have specific meaning in a CAP message
#
# identifier is a unique field for each CAP message
#
# headline is a field which we are not sure if we will use
#
# description is the body of the message
# areas is a list of dicts, with the following items
# * description is a string which populates the areaDesc field
# * polygon is a list of lat/long pairs
#
# previous_provider_messages is a list of previous events (models.py::BroadcastProviderMessage)
# ie a Cancel message would have a unique event but have the event of
# the preceeding Alert message in the previous_provider_messages field
class CBCProxyException(Exception):
pass
class CBCProxyClient:
_lambda_client = None
def init_app(self, app):
if app.config.get('CBC_PROXY_ENABLED'):
self._lambda_client = boto3.client(
'lambda',
region_name='eu-west-2',
aws_access_key_id=app.config['CBC_PROXY_AWS_ACCESS_KEY_ID'],
aws_secret_access_key=app.config['CBC_PROXY_AWS_SECRET_ACCESS_KEY'],
)
def get_proxy(self, provider):
proxy_classes = {
'canary': CBCProxyCanary,
BroadcastProvider.EE: CBCProxyEE,
BroadcastProvider.THREE: CBCProxyThree,
BroadcastProvider.O2: CBCProxyO2,
BroadcastProvider.VODAFONE: CBCProxyVodafone,
}
return proxy_classes[provider](self._lambda_client)
class CBCProxyClientBase(ABC):
@property
@abstractmethod
def lambda_name(self):
pass
@property
@abstractmethod
def failover_lambda_name(self):
pass
@property
@abstractmethod
def LANGUAGE_ENGLISH(self):
pass
@property
@abstractmethod
def LANGUAGE_WELSH(self):
pass
def __init__(self, lambda_client):
self._lambda_client = lambda_client
def send_canary(
self,
identifier,
):
pass
def send_link_test(
self,
identifier,
sequential_number
):
pass
def create_and_send_broadcast(
self, identifier, headline, description, areas, sent, expires, channel, message_number=None
):
pass
# We have not implementated updating a broadcast
def update_and_send_broadcast(
self,
identifier, previous_provider_messages, headline, description, areas,
sent, expires, channel, message_number=None
):
pass
# We have not implemented cancelling a broadcast
def cancel_broadcast(
self,
identifier, previous_provider_messages, headline, description, areas,
sent, expires, message_number=None
):
pass
def _invoke_lambda_with_failover(self, payload):
result = self._invoke_lambda(self.lambda_name, payload)
if not result:
failover_result = self._invoke_lambda(self.failover_lambda_name, payload)
if not failover_result:
raise CBCProxyException(f'Lambda failed for both {self.lambda_name} and {self.failover_lambda_name}')
return result
def _invoke_lambda(self, lambda_name, payload):
payload_bytes = bytes(json.dumps(payload), encoding='utf8')
current_app.logger.info(f"Calling lambda {lambda_name}")
result = self._lambda_client.invoke(
FunctionName=lambda_name,
InvocationType='RequestResponse',
Payload=payload_bytes,
)
current_app.logger.info(f"Finished calling lambda {lambda_name}")
if result['StatusCode'] > 299:
current_app.logger.info(
f"Error calling lambda {lambda_name} with status code { result['StatusCode']}, {result.get('Payload')}"
)
success = False
elif 'FunctionError' in result:
current_app.logger.info(
f"Error calling lambda {lambda_name} with function error { result['Payload'] }"
)
success = False
else:
success = True
return success
def infer_language_from(self, content):
if non_gsm_characters(content):
return self.LANGUAGE_WELSH
return self.LANGUAGE_ENGLISH
class CBCProxyCanary(CBCProxyClientBase):
"""
The canary is a lambda which tests notify's connectivity to the Cell Broadcast AWS infrastructure. It calls the
canary, a specific lambda that does not open a vpn or connect to a provider but just responds from within AWS.
"""
lambda_name = 'canary'
# we don't need a failover lambda for the canary as it doesn't actually make calls out to a CBC
# so we just reuse the normal one in case of a failover scenario
failover_lambda_name = 'canary'
LANGUAGE_ENGLISH = None
LANGUAGE_WELSH = None
def send_canary(
self,
identifier,
):
self._invoke_lambda(self.lambda_name, payload={'identifier': identifier})
class CBCProxyEE(CBCProxyClientBase):
lambda_name = 'ee-1-proxy'
failover_lambda_name = 'ee-2-proxy'
LANGUAGE_ENGLISH = 'en-GB'
LANGUAGE_WELSH = 'cy-GB'
def send_link_test(
self,
identifier,
sequential_number=None,
):
"""
link test - open up a connection to a specific provider, and send them an xml payload with a <msgType> of
test.
"""
payload = {
'message_type': 'test',
'identifier': identifier,
'message_format': 'cap'
}
self._invoke_lambda_with_failover(payload=payload)
def create_and_send_broadcast(
self, identifier, headline, description, areas, sent, expires, channel, message_number=None
):
payload = {
'message_type': 'alert',
'identifier': identifier,
'message_format': 'cap',
'headline': headline,
'description': description,
'areas': areas,
'sent': sent,
'expires': expires,
'language': self.infer_language_from(description),
'channel': channel,
}
self._invoke_lambda_with_failover(payload=payload)
def cancel_broadcast(
self,
identifier, previous_provider_messages,
sent, message_number=None
):
payload = {
'message_type': 'cancel',
'identifier': identifier,
'message_format': 'cap',
"references": [
{
"message_id": str(message.id),
"sent": message.created_at.strftime(DATETIME_FORMAT)
} for message in previous_provider_messages
],
'sent': sent,
}
self._invoke_lambda_with_failover(payload=payload)
class CBCProxyThree(CBCProxyClientBase):
lambda_name = 'three-1-proxy'
failover_lambda_name = 'three-2-proxy'
LANGUAGE_ENGLISH = 'en-GB'
LANGUAGE_WELSH = 'cy-GB'
def send_link_test(
self,
identifier,
sequential_number=None,
):
"""
link test - open up a connection to a specific provider, and send them an xml payload with a <msgType> of
test.
"""
payload = {
'message_type': 'test',
'identifier': identifier,
'message_format': 'cap'
}
self._invoke_lambda_with_failover(payload=payload)
def create_and_send_broadcast(
self, identifier, headline, description, areas, sent, expires, channel, message_number=None
):
payload = {
'message_type': 'alert',
'identifier': identifier,
'message_format': 'cap',
'headline': headline,
'description': description,
'areas': areas,
'sent': sent,
'expires': expires,
'language': self.infer_language_from(description),
'channel': channel,
}
self._invoke_lambda_with_failover(payload=payload)
def cancel_broadcast(
self,
identifier, previous_provider_messages,
sent, message_number=None
):
payload = {
'message_type': 'cancel',
'identifier': identifier,
'message_format': 'cap',
"references": [
{
"message_id": str(message.id),
"sent": message.created_at.strftime(DATETIME_FORMAT)
} for message in previous_provider_messages
],
'sent': sent,
}
self._invoke_lambda_with_failover(payload=payload)
class CBCProxyO2(CBCProxyClientBase):
lambda_name = 'o2-1-proxy'
failover_lambda_name = 'o2-2-proxy'
LANGUAGE_ENGLISH = 'en-GB'
LANGUAGE_WELSH = 'cy-GB'
def send_link_test(
self,
identifier,
sequential_number=None,
):
"""
link test - open up a connection to a specific provider, and send them an xml payload with a <msgType> of
test.
"""
payload = {
'message_type': 'test',
'identifier': identifier,
'message_format': 'cap'
}
self._invoke_lambda_with_failover(payload=payload)
def create_and_send_broadcast(
self, identifier, headline, description, areas, sent, expires, channel, message_number=None
):
payload = {
'message_type': 'alert',
'identifier': identifier,
'message_format': 'cap',
'headline': headline,
'description': description,
'areas': areas,
'sent': sent,
'expires': expires,
'language': self.infer_language_from(description),
'channel': channel,
}
self._invoke_lambda_with_failover(payload=payload)
def cancel_broadcast(
self,
identifier, previous_provider_messages,
sent, message_number=None
):
payload = {
'message_type': 'cancel',
'identifier': identifier,
'message_format': 'cap',
"references": [
{
"message_id": str(message.id),
"sent": message.created_at.strftime(DATETIME_FORMAT)
} for message in previous_provider_messages
],
'sent': sent,
}
self._invoke_lambda_with_failover(payload=payload)
class CBCProxyVodafone(CBCProxyClientBase):
lambda_name = 'vodafone-1-proxy'
failover_lambda_name = 'vodafone-2-proxy'
LANGUAGE_ENGLISH = 'English'
LANGUAGE_WELSH = 'Welsh'
def send_link_test(
self,
identifier,
sequential_number,
):
"""
link test - open up a connection to a specific provider, and send them an xml payload with a <msgType> of
test.
"""
payload = {
'message_type': 'test',
'identifier': identifier,
'message_number': sequential_number,
'message_format': 'ibag'
}
self._invoke_lambda_with_failover(payload=payload)
def create_and_send_broadcast(
self, identifier, message_number, headline, description, areas, sent, expires, channel
):
payload = {
'message_type': 'alert',
'identifier': identifier,
'message_number': message_number,
'message_format': 'ibag',
'headline': headline,
'description': description,
'areas': areas,
'sent': sent,
'expires': expires,
'language': self.infer_language_from(description),
'channel': channel,
}
self._invoke_lambda_with_failover(payload=payload)
def cancel_broadcast(
self, identifier, previous_provider_messages, sent, message_number
):
payload = {
'message_type': 'cancel',
'identifier': identifier,
'message_number': message_number,
'message_format': 'ibag',
"references": [
{
"message_id": str(message.id),
"message_number": format_sequential_number(message.message_number),
"sent": message.created_at.strftime(DATETIME_FORMAT)
} for message in previous_provider_messages
],
'sent': sent,
}
self._invoke_lambda_with_failover(payload=payload)