Move MongoDB classes into a seperate db module (#62)

* move album class into mongodb dir

* inherit AlbumMethods at DB Initialization level

* move album -> db/mongodb

* move mongodb classes into separate package

server/app/db/mongodb/albums.py

@@ -0,0 +1,60 @@
+"""
+This file contains the Album class for interacting with
+album documents in MongoDB.
+"""
+from app import db
+from app.db.mongodb import convert_many
+from app.db.mongodb import convert_one
+from app.db.mongodb import MongoAlbums
+from app.models import Album
+from bson import ObjectId
+
+
+class Albums(MongoAlbums):
+    """
+    The class for all album-related database operations.
+    """
+
+    def insert_album(self, album: Album) -> None:
+        """
+        Inserts a new album object into the database.
+        """
+        album = album.__dict__
+        return self.collection.update_one(
+            {
+                "album": album["title"],
+                "artist": album["artist"]
+            },
+            {
+                "$set": album
+            },
+            upsert=True,
+        ).upserted_id
+
+    def get_all_albums(self) -> list:
+        """
+        Returns all the albums in the database.
+        """
+        albums = self.collection.find()
+        return convert_many(albums)
+
+    def get_album_by_id(self, id: str) -> dict:
+        """
+        Returns a single album matching the id in the query params.
+        """
+        album = self.collection.find_one({"_id": ObjectId(id)})
+        return convert_one(album)
+
+    def get_album_by_name(self, name: str, artist: str) -> dict:
+        """
+        Returns a single album matching the name in the query params.
+        """
+        album = self.collection.find_one({"album": name, "artist": artist})
+        return convert_one(album)
+
+    def get_album_by_artist(self, name: str) -> dict:
+        """
+        Returns a single album matching the artist in the query params.
+        """
+        album = self.collection.find_one({"albumartist": name})
+        return convert_one(album)