feat: Get the first model from a query.

Artmann · Jul 12, 2020 · 0a624f6 · 0a624f6
1 parent 7f5caa3
commit 0a624f6
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Showing 2 changed files with 184 additions and 114 deletions.
diff --git a/src/base-model.spec.ts b/src/base-model.spec.ts
@@ -40,45 +40,6 @@ describe('BaseModel', () => {
     });
   });
 
-  describe('find', () => {
-
-    it('returns null for non existing documents.', async() => {
-      const book = await Book.find('abc-123');
-
-      expect(collection.findOne).toHaveBeenCalledWith({
-        _id: 'abc-123'
-      });
-
-      expect(book).toBeNull();
-    });
-
-    it('finds a document by id.', async() => {
-      collection.findOne.mockResolvedValue({
-        _id: new ObjectId('5f0aeaeacff57e3ec676b340'),
-        authorId: 'author-1',
-        createdAt: 1594552340652,
-        isbn: '978-3-16-148410-0',
-        title: 'Esix for dummies',
-        updatedAt: 0
-      });
-
-      const book = await Book.find('5f0aeaeacff57e3ec676b340');
-
-      expect(collection.findOne).toHaveBeenCalledWith({
-        _id: '5f0aeaeacff57e3ec676b340'
-      });
-
-      expect(book).toEqual({
-        authorId: 'author-1',
-        createdAt: 1594552340652,
-        id: '5f0aeaeacff57e3ec676b340',
-        isbn: '978-3-16-148410-0',
-        title: 'Esix for dummies',
-        updatedAt: 0
-      });
-    });
-  });
-
   describe('all',  () => {
     it('finds all documets.', async() => {
       const cursor = createCursor([
@@ -139,70 +100,6 @@ describe('BaseModel', () => {
     });
   });
 
-  describe('where', () => {
-    it ('finds all documets that matches a query', async() => {
-      const cursor = createCursor([
-        {
-          _id: new ObjectId('5f0aeaeacff57e3ec676b340'),
-          authorId: 'author-1',
-          createdAt: 1594552340652,
-          isbn: '978-3-16-148410-0',
-          title: 'Esix for dummies',
-          updatedAt: 0
-        },
-        {
-          _id: new ObjectId('5f0aefba348289a81889a920'),
-          authorId: 'author-1',
-          createdAt: 1594552346653,
-          isbn: '978-3-16-148410-1',
-          title: 'Esix for dummies 2',
-          updatedAt: 0
-        }
-      ]);
-
-      collection.find.mockReturnValue(cursor);
-
-      const books = await Book.where('authorId', 'author-1').get();
-
-      expect(collection.find).toHaveBeenCalledWith({
-        authorId: 'author-1'
-      });
-
-      expect(books).toEqual([
-        {
-          authorId: 'author-1',
-          createdAt: 1594552340652,
-          id: '5f0aeaeacff57e3ec676b340',
-          isbn: '978-3-16-148410-0',
-          title: 'Esix for dummies',
-          updatedAt: 0
-        },
-        {
-          authorId: 'author-1',
-          createdAt: 1594552346653,
-          id: '5f0aefba348289a81889a920',
-          isbn: '978-3-16-148410-1',
-          title: 'Esix for dummies 2',
-          updatedAt: 0
-        }
-      ]);
-    });
-
-    it('returns an empty array if there is no matching documents.', async() => {
-      const cursor = createCursor([]);
-
-      collection.find.mockReturnValue(cursor);
-
-      const books = await Book.where('authorId', 'author-2').get();
-
-      expect(collection.find).toHaveBeenCalledWith({
-        authorId: 'author-2'
-      });
-
-      expect(books).toEqual([]);
-    });
-  });
-
   describe('create', () => {
     it('creates a new Model.', async() => {
       const dateSpy = jest.spyOn(Date, 'now');
@@ -290,4 +187,163 @@ describe('BaseModel', () => {
       });
     });
   });
+
+  describe('find', () => {
+
+    it('returns null for non existing documents.', async() => {
+      collection.findOne.mockReturnValue(null);
+
+      const book = await Book.find('abc-123');
+
+      expect(collection.findOne).toHaveBeenCalledWith({
+        _id: 'abc-123'
+      });
+
+      expect(book).toBeNull();
+    });
+
+    it('finds a document by id.', async() => {
+      collection.findOne.mockResolvedValue({
+        _id: new ObjectId('5f0aeaeacff57e3ec676b340'),
+        authorId: 'author-1',
+        createdAt: 1594552340652,
+        isbn: '978-3-16-148410-0',
+        title: 'Esix for dummies',
+        updatedAt: 0
+      });
+
+      const book = await Book.find('5f0aeaeacff57e3ec676b340');
+
+      expect(collection.findOne).toHaveBeenCalledWith({
+        _id: '5f0aeaeacff57e3ec676b340'
+      });
+
+      expect(book).toEqual({
+        authorId: 'author-1',
+        createdAt: 1594552340652,
+        id: '5f0aeaeacff57e3ec676b340',
+        isbn: '978-3-16-148410-0',
+        title: 'Esix for dummies',
+        updatedAt: 0
+      });
+    });
+  });
+
+  describe('first', () => {
+    it('returns the first model.', async() => {
+      const cursor = createCursor([
+        {
+          _id: new ObjectId('5f0aeaeacff57e3ec676b340'),
+          authorId: 'author-1',
+          createdAt: 1594552340652,
+          isbn: '978-3-16-148410-0',
+          title: 'Esix for dummies',
+          updatedAt: 0
+        },
+        {
+          _id: new ObjectId('5f0aefba348289a81889a920'),
+          authorId: 'author-1',
+          createdAt: 1594552346653,
+          isbn: '978-3-16-148410-1',
+          title: 'Esix for dummies 2',
+          updatedAt: 0
+        }
+      ]);
+
+      collection.find.mockReturnValue(cursor);
+
+      const book = await Book.where('authorId', 'author-1').first();
+
+      expect(collection.find).toHaveBeenCalledWith({
+        authorId: 'author-1'
+      });
+
+      expect(book).toEqual({
+        authorId: 'author-1',
+        createdAt: 1594552340652,
+        id: '5f0aeaeacff57e3ec676b340',
+        isbn: '978-3-16-148410-0',
+        title: 'Esix for dummies',
+        updatedAt: 0
+      });
+    });
+
+    it('returns null if there is no matching models.', async() => {
+      const cursor = createCursor([]);
+
+      collection.find.mockReturnValue(cursor);
+
+      const book = await Book.where('authorId', 'author-1').first();
+
+      expect(collection.find).toHaveBeenCalledWith({
+        authorId: 'author-1'
+      });
+
+      expect(book).toBeNull();
+    });
+  });
+
+  describe('where', () => {
+    it ('finds all documets that matches a query', async() => {
+      const cursor = createCursor([
+        {
+          _id: new ObjectId('5f0aeaeacff57e3ec676b340'),
+          authorId: 'author-1',
+          createdAt: 1594552340652,
+          isbn: '978-3-16-148410-0',
+          title: 'Esix for dummies',
+          updatedAt: 0
+        },
+        {
+          _id: new ObjectId('5f0aefba348289a81889a920'),
+          authorId: 'author-1',
+          createdAt: 1594552346653,
+          isbn: '978-3-16-148410-1',
+          title: 'Esix for dummies 2',
+          updatedAt: 0
+        }
+      ]);
+
+      collection.find.mockReturnValue(cursor);
+
+      const books = await Book.where('authorId', 'author-1').get();
+
+      expect(collection.find).toHaveBeenCalledWith({
+        authorId: 'author-1'
+      });
+
+      expect(books).toEqual([
+        {
+          authorId: 'author-1',
+          createdAt: 1594552340652,
+          id: '5f0aeaeacff57e3ec676b340',
+          isbn: '978-3-16-148410-0',
+          title: 'Esix for dummies',
+          updatedAt: 0
+        },
+        {
+          authorId: 'author-1',
+          createdAt: 1594552346653,
+          id: '5f0aefba348289a81889a920',
+          isbn: '978-3-16-148410-1',
+          title: 'Esix for dummies 2',
+          updatedAt: 0
+        }
+      ]);
+    });
+
+    it('returns an empty array if there is no matching documents.', async() => {
+      const cursor = createCursor([]);
+
+      collection.find.mockReturnValue(cursor);
+
+      const books = await Book.where('authorId', 'author-2').get();
+
+      expect(collection.find).toHaveBeenCalledWith({
+        authorId: 'author-2'
+      });
+
+      expect(books).toEqual([]);
+    });
+  });
 });
diff --git a/src/query-builder.ts b/src/query-builder.ts
@@ -46,6 +46,20 @@ export default class QueryBuilder<T> {
     return this.createInstance(document);
   }
 
+  async first(): Promise<T | null> {
+    const models = await this.execute();
+
+    if (models.length === 0) {
+      return null;
+    }
+
+    return models[0];
+  }
+
+  async get(): Promise<T[]> {
+    return this.execute();
+  }
+
   where(query: Query): QueryBuilder<T>;
   where(key: string, value: any): QueryBuilder<T>;
   where(queryOrKey: Query | string, value?: any): QueryBuilder<T> {
@@ -59,17 +73,6 @@ export default class QueryBuilder<T> {
     return this;
   }
 
-  async get(): Promise<T[]> {
-    const collection = await this.getCollection();
-    const documents = await collection.find(this.query).toArray();
-
-    const records = documents
-      .filter(document => document)
-      .map((document): T => this.createInstance(document));
-
-    return records;
-  }
-
   private createInstance<T>(document: Document): T {
     const instance = new this.ctor() as any;
 
@@ -129,4 +132,15 @@ export default class QueryBuilder<T> {
 
     return database;
   }
+
+  private async execute(): Promise<T[]> {
+    const collection = await this.getCollection();
+    const documents = await collection.find(this.query).toArray();
+
+    const records = documents
+      .filter(document => document)
+      .map((document): T => this.createInstance(document));
+
+    return records;
+  }
 }