Merge pull request #4 from oslabs-beta/emilia/query2

updated query.ts

Author: wgreco13

lib/query.ts

@@ -3,18 +3,30 @@
 import { Collection } from '../deps.ts';
 import { Connection } from './connections.ts';
 
+interface MatchInterface {
+  $match: {[unknownKeyName: string]: string};
+}
+ 
+interface GroupInterface { 
+  $group: {
+    [unknownKeyName: string]: string | {$sum: number};
+  }
+
+}
+
+
 class Query {
   public collectionName: string;
   // Refactor how connection is brought in
   public connection: Connection;
-
+  
   constructor(collectionName: string) {
     this.collectionName = collectionName;
     this.connection = new Connection(
       'mongodb+srv://wgreco13:g3HUuathwbVEisEj@cluster0.adcc3.mongodb.net/dangoDB?authMechanism=SCRAM-SHA-1'
     );
   }
-
+/*Returns one document that satisfies the specified query criteria on the collection or view.  */
   public async findOne(queryObject: Record<string, string>) {
     try {
       const db = await this.connection.connect();
@@ -24,13 +36,98 @@ class Query {
       console.log(data);
 
       await this.connection.disconnect();
+
     } catch (error) {
       throw new Error(`Error in findOne function. ${error}`);
     }
   }
+  /*Selects documents in a collection or view and returns a cursor to the selected documents. */
+  public async find(allQueryObjects?: object) {
+    try {
+      const db = await this.connection.connect(); 
+      
+      const collection = db.collection(this.collectionName);
+      const data = await collection.find(allQueryObjects);
+      const dataRes = await data.toArray()
+   
+      console.log(dataRes); 
+
+      await this.connection.disconnect();
+  
+    } catch (error) {
+      throw new Error(`Error in find function. ${error}`);
+    }
+  }
+  /* Returns the count of documents that match the query for a collection or view. */
+  public async countDocuments(queryObject: Record<string, string>) {
+    try {
+      const db = await this.connection.connect(); 
+      
+      const collection = db.collection(this.collectionName);
+      const data = await collection.countDocuments(queryObject);
+
+  
+      console.log(data); 
+
+      await this.connection.disconnect();
+  
+    } catch (error) {
+      throw new Error(`Error in countDocuments function. ${error}`);
+    }
+  }
+  /*estimatedDocumentCount() = Returns the count of all documents in a collection or view. The method wraps the count command. */
+  public async estimatedDocumentCount() {
+    try {
+      const db = await this.connection.connect(); 
+      
+      const collection = db.collection(this.collectionName);
+      const data = await collection.estimatedDocumentCount();
+  
+      console.log(data); 
+
+      await this.connection.disconnect();
+  
+    } catch (error) {
+      throw new Error(`Error in estimatedDocumentCount function. ${error}`);
+    }
+  }
+   /*Aggregation operations process multiple documents and return computed results. You can use aggregation operations to:
+      Group values from multiple documents together.
+      Perform operations on the grouped data to return a single result.
+      Analyze data changes over time. */
+
+  
+      
+  //  public async aggregate(arg1: [{$match:{[unknownKeyName:string]: string}}]) {
+  public async aggregate(arg1: MatchInterface [], arg2: GroupInterface []) {
+      const db = await this.connection.connect(); 
+      
+      const collection = db.collection(this.collectionName);
+      const data = await collection.aggregate(arg1, arg2);
+      const dataRes = await data.toArray()
+   
+      console.log(dataRes); 
+
+      await this.connection.disconnect();
+  
+    } catch (error) {
+      throw new Error(`Error in aggregate function. ${error}`);
+    }
+  
+ 
+
 }
 
+
 const query = new Query('new');
-query.findOne({ username: 'test' });
+
+// query.findOne({ username: 'test' });
+// query.find()
+// query.countDocuments({ username: 'test' });
+// query.estimatedDocumentCount(); 
+query.aggregate([{ $match: { username: 'test' }}, { $group: { _id: '$username', total: { $sum: 1 }}}])
 
 export { Query };
+
+
+