From 6557b7157f880e775fbdf5db8a78bcc240abd9f6 Mon Sep 17 00:00:00 2001
From: Son NK <>
Date: Mon, 12 Oct 2020 17:37:04 +0200
Subject: [PATCH] handle the Paddle 147 error

---
 app/dashboard/views/billing.py | 30 ++++++++++++++++++------------
 app/paddle_utils.py            | 14 ++++++++++++--
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/app/dashboard/views/billing.py b/app/dashboard/views/billing.py
index 9f8def67..de08c434 100644
--- a/app/dashboard/views/billing.py
+++ b/app/dashboard/views/billing.py
@@ -38,34 +38,40 @@ def billing():
             return redirect(url_for("dashboard.billing"))
         elif request.form.get("form-name") == "change-monthly":
             LOG.debug(f"User {current_user} changes to monthly plan")
-            success = change_plan(sub.subscription_id, PADDLE_MONTHLY_PRODUCT_ID)
+            success, msg = change_plan(sub.subscription_id, PADDLE_MONTHLY_PRODUCT_ID)
 
             if success:
                 sub.plan = PlanEnum.monthly
                 db.session.commit()
                 flash("Your subscription has been updated", "success")
             else:
-                flash(
-                    "Something went wrong, sorry for the inconvenience. Please retry. "
-                    "We are already notified and will be on it asap",
-                    "error",
-                )
+                if msg:
+                    flash(msg, "error")
+                else:
+                    flash(
+                        "Something went wrong, sorry for the inconvenience. Please retry. "
+                        "We are already notified and will be on it asap",
+                        "error",
+                    )
 
             return redirect(url_for("dashboard.billing"))
         elif request.form.get("form-name") == "change-yearly":
             LOG.debug(f"User {current_user} changes to yearly plan")
-            success = change_plan(sub.subscription_id, PADDLE_YEARLY_PRODUCT_ID)
+            success, msg = change_plan(sub.subscription_id, PADDLE_YEARLY_PRODUCT_ID)
 
             if success:
                 sub.plan = PlanEnum.yearly
                 db.session.commit()
                 flash("Your subscription has been updated", "success")
             else:
-                flash(
-                    "Something went wrong, sorry for the inconvenience. Please retry. "
-                    "We are already notified and will be on it asap",
-                    "error",
-                )
+                if msg:
+                    flash(msg, "error")
+                else:
+                    flash(
+                        "Something went wrong, sorry for the inconvenience. Please retry. "
+                        "We are already notified and will be on it asap",
+                        "error",
+                    )
 
             return redirect(url_for("dashboard.billing"))
 
diff --git a/app/paddle_utils.py b/app/paddle_utils.py
index ed953440..20d04042 100644
--- a/app/paddle_utils.py
+++ b/app/paddle_utils.py
@@ -78,7 +78,8 @@ def cancel_subscription(subscription_id: int) -> bool:
     return res["success"]
 
 
-def change_plan(subscription_id: int, plan_id) -> bool:
+def change_plan(subscription_id: str, plan_id) -> (bool, str):
+    """return whether the operation is successful and an optional error message"""
     r = requests.post(
         "https://vendors.paddle.com/api/2.0/subscription/users/update",
         data={
@@ -93,5 +94,14 @@ def change_plan(subscription_id: int, plan_id) -> bool:
         LOG.exception(
             f"cannot change subscription {subscription_id} to {plan_id}, paddle response: {res}"
         )
+        try:
+            # "unable to complete the resubscription because we could not charge the customer for the resubscription"
+            if res["error"]["code"] == 147:
+                return False, "Your card cannot be charged"
+        except:
+            LOG.warning("Cannot parse error code from %s", res)
+            return False, ""
 
-    return res["success"]
+        return False, ""
+
+    return res["success"], ""