feat: implement PersistenceProvider#get in all providers

Author: Jblew

src/persistence/FirestorePersistenceProvider.ts

@@ -40,6 +40,10 @@ export class FirestorePersistenceProvider implements PersistenceProvider {
         return result;
     }
 
+    public async get(collectionName: string, recordName: string): Promise<PersistenceRecord> {
+        return await this.getRecord(collectionName, recordName);
+    }
+
     public setDebugFn(debugFn: (msg: string) => void) {
         this.debugFn = debugFn;
     }

src/persistence/PersistenceProviderMock.ts

@@ -20,6 +20,10 @@ export class PersistenceProviderMock implements PersistenceProvider {
         return result;
     }
 
+    public async get(collectionName: string, recordName: string): Promise<PersistenceRecord> {
+        return await this.getRecord(collectionName, recordName);
+    }
+
     public setDebugFn(debugFn: (msg: string) => void) {
         //
     }

src/persistence/RealtimeDbPersistenceProvider.ts

@@ -27,9 +27,8 @@ export class RealtimeDbPersistenceProvider implements PersistenceProvider {
         recordName: string,
         updaterFn: (record: PersistenceRecord) => PersistenceRecord,
     ): Promise<PersistenceRecord> {
-        const refName = `${collectionName}/${recordName}`;
+        const ref = this.getDatabaseRef(collectionName, recordName);
 
-        const ref = this.database.ref(refName);
         const response = await ref.transaction(dataToUpdate => this.wrapUpdaterFn(updaterFn)(dataToUpdate));
         const { snapshot, committed } = response;
         if (!snapshot) throw new Error("RealtimeDbPersistenceProvider: realtime db didn't respond with data");
@@ -40,6 +39,15 @@ export class RealtimeDbPersistenceProvider implements PersistenceProvider {
         else return data as PersistenceRecord;
     }
 
+    public async get(collectionName: string, recordName: string): Promise<PersistenceRecord> {
+        const snapshot = await this.getDatabaseRef(collectionName, recordName).once("value");
+        if (!snapshot) return this.createEmptyRecord();
+
+        const data = snapshot.val();
+        if (data === null) return this.createEmptyRecord();
+        else return data as PersistenceRecord;
+    }
+
     public setDebugFn(debugFn: (msg: string) => void) {
         this.debugFn = debugFn;
     }
@@ -58,6 +66,11 @@ export class RealtimeDbPersistenceProvider implements PersistenceProvider {
         };
     }
 
+    private getDatabaseRef(collectionName: string, recordName: string) {
+        const refName = `${collectionName}/${recordName}`;
+        return this.database.ref(refName);
+    }
+
     private createEmptyRecord(): PersistenceRecord {
         return {
             u: [],

src/types/RealtimeDbEquivalent.ts

@@ -8,6 +8,7 @@ export namespace RealtimeDbEquivalent {
             updateFn: (data: any) => any,
             completeFn?: any,
         ): Promise<{ committed: boolean; snapshot: DataSnapshot | null }>;
+        once(eventType: "value"): Promise<DataSnapshot>;
     }
 
     export interface DataSnapshot {