From d566b4da163ffe9b0d8e90a0e98bf9424a879fec Mon Sep 17 00:00:00 2001
From: Mark Veidemanis <m@zm.is>
Date: Mon, 28 Feb 2022 20:03:21 +0000
Subject: [PATCH] Begin implementing TrueLayer API

---
 handler/sinks/truelayer.py | 94 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 handler/sinks/truelayer.py

diff --git a/handler/sinks/truelayer.py b/handler/sinks/truelayer.py
new file mode 100644
index 0000000..f914f6e
--- /dev/null
+++ b/handler/sinks/truelayer.py
@@ -0,0 +1,94 @@
+# Twisted/Klein imports
+from twisted.logger import Logger
+
+# Other library imports
+import requests
+from json import dumps
+from simplejson.errors import JSONDecodeError
+
+# Project imports
+from settings import settings
+
+
+class TrueLayer(object):
+    """
+    Class to manage calls to Open Banking APIs through TrueLayer.
+    """
+
+    def __init__(self):
+        self.log = Logger("truelayer")
+        self.token = None
+        # self.auth = HTTPBasicAuth(settings.Yapily.ID, settings.Yapily.Key)
+        # print(self.get_institutions())
+        # authorisation = self.get_authorisation("monzo_ob", settings.Yapily.CallbackURL)
+        # print("authirisation", authorisation)
+
+    def setup_auth(self):
+        """
+        Exchange an authentication code for an access and refresh token.
+        """
+        headers = {"Content-Type": "application/x-www-form-urlencoded"}
+        data = {
+            "grant_type": "authorization_code",
+            "code": settings.TrueLayer.Monzo_AuthCode,
+            "client_id": settings.TrueLayer.ID,
+            "client_secret": settings.TrueLayer.Key,
+            "redirect_uri": "https://console.truelayer.com/redirect-page",
+        }
+        r = requests.post(f"{settings.TrueLayer.Base}/connect/token", data=data, headers=headers)
+        try:
+            parsed = r.json()
+        except JSONDecodeError:
+            self.log.error("Error parsing access token response: {content}", content=r.content)
+            return False
+        print("PARSED", parsed)
+        if r.status_code == 200:
+            try:
+                settings.TrueLayer.Monzo_RefreshToken = parsed["refresh_token"]
+                settings.TrueLayer.Monzo_SetupToken = "0"
+                settings.write()
+                self.log.info("Refreshed refresh token")
+                self.token = parsed["access_token"]
+                self.log.info("Refreshed access token")
+            except KeyError:
+                self.log.error(f"Token authorization didn't contain refresh or access token: {parsed}", parsed=parsed)
+                return False
+        else:
+            self.log.error(f"Cannot refresh token: {parsed}", parsed=parsed)
+            return False
+
+    def get_new_token(self, _=None):
+        """
+        Exchange our refresh token for an access token.
+        """
+        print("calling get new token")
+        pass
+
+    def get_institutions(self, filter_name=None):
+        """
+        Get a list of supported institutions.
+        """
+
+        path = f"{settings.Yapily.Base}/institutions"
+        r = requests.get(path, auth=self.auth)
+        try:
+            parsed = r.json()
+        except JSONDecodeError:
+            self.log.error("Error parsing institutions response: {content}", content=r.content)
+            return False
+        return parsed
+
+    def get_authorisation(self, institution_id, callback_url):
+        """
+        Get an authorisation URL for linking a bank account of an institution.
+        """
+        headers = {"Content-Type": "application/json"}
+        data = {"applicationUserId": "account-data-and-transactions-tutorial", "institutionId": institution_id, "callback": callback_url}
+        path = f"{settings.Yapily.Base}/account-auth-requests"
+        r = requests.post(path, headers=headers, data=dumps(data), auth=self.auth)
+        try:
+            parsed = r.json()
+        except JSONDecodeError:
+            self.log.error("Error parsing institutions response: {content}", content=r.content)
+            return False
+        return parsed