Removed duplicate stripe customers&subscriptions

refs TryGhost#12100

We want to add unique constraints to the subscription_id and customer_id
fields in the members_stripe_customers_subscriptions and
members_stripe_customers tables respectively. In order to do this safely
we must first ensure that no duplicate entries exist.

core/server/data/migrations/versions/3.28/01-remove-duplicate-subscriptions.js

@@ -0,0 +1,45 @@
+const logging = require('../../../../../shared/logging');
+
+module.exports = {
+    config: {
+        transaction: true
+    },
+
+    async up({transacting: knex}) {
+        const duplicates = await knex('members_stripe_customers_subscriptions')
+            .select('subscription_id')
+            .count('subscription_id as count')
+            .groupBy('subscription_id')
+            .having('count', '>', 1);
+
+        if (!duplicates.length) {
+            logging.info('No duplicate subscriptions found');
+            return;
+        }
+
+        logging.info(`Found ${duplicates.length} duplicate stripe subscriptions`);
+        for (const duplicate of duplicates) {
+            const subscriptions = await knex('members_stripe_customers_subscriptions')
+                .select()
+                .where('subscription_id', duplicate.subscription_id);
+
+            const orderedSubscriptions = subscriptions.sort((subA, subB) => {
+                return subB.updated_at - subA.updated_at;
+            });
+
+            const [newestSubscription, ...olderSubscriptions] = orderedSubscriptions;
+
+            logging.info(`Keeping newest subscription ${newestSubscription.id} - ${newestSubscription.subscription_id}, last updated at ${newestSubscription.updated_at}`);
+
+            for (const subscriptionToDelete of olderSubscriptions) {
+                logging.info(`Deleting duplicate subscription ${subscriptionToDelete.id} - ${subscriptionToDelete.subscription_id}, last updated at ${subscriptionToDelete.updated_at}`);
+                await knex('members_stripe_customers_subscriptions')
+                    .where({id: subscriptionToDelete.id})
+                    .del();
+            }
+        }
+    },
+
+    // noop for down
+    async down() {}
+};

core/server/data/migrations/versions/3.28/02-remove-duplicate-customers.js

@@ -0,0 +1,45 @@
+const logging = require('../../../../../shared/logging');
+
+module.exports = {
+    config: {
+        transaction: true
+    },
+
+    async up({transacting: knex}) {
+        const duplicates = await knex('members_stripe_customers')
+            .select('customer_id')
+            .count('customer_id as count')
+            .groupBy('customer_id')
+            .having('count', '>', 1);
+
+        if (!duplicates.length) {
+            logging.info('No duplicate customers found');
+            return;
+        }
+
+        logging.info(`Found ${duplicates.length} duplicate stripe customers`);
+        for (const duplicate of duplicates) {
+            const customers = await knex('members_stripe_customers')
+                .select()
+                .where('customer_id', duplicate.customer_id);
+
+            const orderedCustomers = customers.sort((subA, subB) => {
+                return subB.updated_at - subA.updated_at;
+            });
+
+            const [newestCustomer, ...olderCustomers] = orderedCustomers;
+
+            logging.info(`Keeping newest customer ${newestCustomer.id} - ${newestCustomer.customer_id}, last updated at ${newestCustomer.updated_at}`);
+
+            for (const customerToDelete of olderCustomers) {
+                logging.info(`Deleting duplicate customer ${customerToDelete.id} - ${customerToDelete.customer_id}, last updated at ${customerToDelete.updated_at}`);
+                await knex('members_stripe_customers')
+                    .where({id: customerToDelete.id})
+                    .del();
+            }
+        }
+    },
+
+    // noop for down
+    async down() {}
+};