fix: Increment race condition (#182)

Author: floydya

docs/useRebar/document/document-global.md

@@ -67,3 +67,27 @@ async function doSomething() {
     document.setBulk({ totalMoneyCreated: 200, totalMoneyDestroyed: 200 });
 }
 ```
+
+
+### unset
+
+Delete a specific field from the document.
+
+```ts
+async function doSomething() {
+    const document = await Rebar.document.global.useGlobal<MyDataType>('my-identifier-goes-here-for-my-document');
+    document.unset('totalMoneyCreated');
+}
+```
+
+### increment
+
+Increment a specific field by a specific amount. It uses 1 as default amount.
+
+```ts
+async function doSomething() {
+    const document = await Rebar.document.global.useGlobal<MyDataType>('my-identifier-goes-here-for-my-document');
+    document.increment('totalMoneyCreated'); // Increment by 1
+    document.increment('totalMoneyCreated', 200); // Increment by 200
+}
+```

src/main/server/document/global.ts

@@ -61,16 +61,43 @@ export async function useGlobal<T extends Object = Object>(identifier: string) {
         return await db.update({ _id: data[identifier]._id, ...newData }, CollectionNames.Global);
     }
 
+    /**
+     * Unset a field from your global document
+     *
+     * @param {string} fieldName
+     * @returns {Promise<boolean>}
+     */
     async function unset(fieldName: string): Promise<boolean> {
         delete data[identifier][fieldName];
         return await db.unset(identifier, [fieldName], CollectionNames.Global);
     }
 
+    /**
+     * Increment a field in your global document
+     *
+     * @param {string} fieldName Field to increment
+     * @param {number} value Value to increment by, defaults to 1
+     * @returns {number} The new value of the field
+     */
+    async function increment(fieldName: string, value: number = 1): Promise<number> {
+        const client = await db.getClient();
+        const updatedValue = await client
+            .collection(CollectionNames.Global)
+            .findOneAndUpdate(
+                { _id: data[identifier]._id },
+                { $inc: { [fieldName]: value } },
+                { upsert: true, returnDocument: 'after' },
+            );
+        data[identifier][fieldName] = updatedValue.value[fieldName];
+        return data[identifier][fieldName];
+    }
+
     return {
         get,
         getField,
         set,
         setBulk,
         unset,
+        increment,
     };
 }

src/main/server/document/increment.ts

@@ -10,9 +10,7 @@ async function init() {
 
 export function useIncrementalId(key: string) {
     async function getNext() {
-        const value: number = incremental.getField(key) ?? 0;
-        await incremental.set(key, value + 1);
-        return value + 1;
+        return await incremental.increment(key);
     }
 
     return {