Replaces MongoDB support with PostgreSQL (#151)

- All schemas have been rewritten to a relational model
- All services have been rewritten to accommodate the new data model
- Adds idempotency keys to core endpoints allowing you to retry requests with no additional side effects
- Adds staged jobs to avoid putting jobs in the queue when transactions abort
- Adds atomic transactions to all methods with access to the data layer

Co-authored-by: Oliver Windall Juhl <oliver@mrbltech.com>

packages/medusa/src/subscribers/order.js

@@ -1,101 +1,58 @@
 class OrderSubscriber {
   constructor({
-    paymentProviderService,
-    customerService,
+    manager,
     eventBusService,
     discountService,
+    giftCardService,
     totalsService,
     orderService,
     regionService,
   }) {
+    this.manager_ = manager
     this.totalsService_ = totalsService
 
-    this.paymentProviderService_ = paymentProviderService
-
-    this.customerService_ = customerService
-
     this.discountService_ = discountService
 
+    this.giftCardService_ = giftCardService
+
     this.orderService_ = orderService
 
     this.regionService_ = regionService
 
     this.eventBus_ = eventBusService
 
-    this.eventBus_.subscribe("order.placed", async order => {
-      await this.customerService_.addOrder(order.customer_id, order._id)
+    this.eventBus_.subscribe("order.placed", this.handleOrderPlaced)
+  }
 
-      const address = {
-        ...order.shipping_address,
-      }
-      delete address._id
-
-      await this.customerService_.addAddress(order.customer_id, address)
+  handleOrderPlaced = async data => {
+    const order = await this.orderService_.retrieve(data.id, {
+      select: ["subtotal"],
+      relations: ["discounts", "items", "gift_cards"],
     })
 
-    this.eventBus_.subscribe("order.placed", this.handleDiscounts)
-
-    this.eventBus_.subscribe("order.placed", this.handleGiftCards)
-  }
-
-  handleDiscounts = async order => {
     await Promise.all(
-      order.discounts.map(async d => {
-        const subtotal = await this.totalsService_.getSubtotal(order)
-        if (d.is_giftcard) {
-          const discountRule = {
-            ...d.discount_rule,
-            value: Math.max(0, d.discount_rule.value - subtotal),
-          }
-
-          delete discountRule._id
-
-          return this.discountService_.update(d._id, {
-            discount_rule: discountRule,
-            usage_count: d.usage_count + 1,
-            disabled: discountRule.value === 0,
-          })
-        } else {
-          return this.discountService_.update(d._id, {
-            usage_count: d.usage_count + 1,
-          })
-        }
-      })
-    )
-  }
-
-  handleGiftCards = async order => {
-    const region = await this.regionService_.retrieve(order.region_id)
-    const items = await Promise.all(
       order.items.map(async i => {
         if (i.is_giftcard) {
-          const giftcard = await this.discountService_
-            .generateGiftCard(i.content.unit_price, region._id)
-            .then(result => {
-              this.eventBus_.emit("order.gift_card_created", {
-                line_item: i,
-                currency_code: region.currency_code,
-                tax_rate: region.tax_rate,
-                giftcard: result,
-                email: order.email,
-              })
-              return result
+          for (let qty = 0; qty < i.quantity; qty++) {
+            await this.giftCardService_.create({
+              region_id: order.region_id,
+              order_id: order.id,
+              value: i.unit_price,
+              balance: i.unit_price,
+              metadata: i.metadata,
             })
-          return {
-            ...i,
-            metadata: {
-              ...i.metadata,
-              giftcard: giftcard._id,
-            },
           }
         }
-        return i
       })
     )
 
-    return this.orderService_.update(order._id, {
-      items,
-    })
+    await Promise.all(
+      order.discounts.map(async d => {
+        return this.discountService_.update(d.id, {
+          usage_count: d.usage_count + 1,
+        })
+      })
+    )
   }
 }