Datastores

backend-services/comment-service-2/src/Datastores/CommentDataStore.ts

+import CommentSchema from "../Database/Schemas/CommentSchema";
+import FriendSchema from "../Database/Schemas/CommentSchema";
+import { Comment } from "../Types/Comment";
+import { DataStore } from "./DataStore";
+
+/**
+ * Contains actions pertaining to storing and accessing Comments
+ */
+class CommentDataStore extends DataStore<any> {
+  /**
+   * Create a new friend relation between two users.
+   * @param u1
+   * @param u2
+   * @returns
+   */
+  public newComment = async (
+    postId: string,
+    authorId: string,
+    content: string,
+    isPostAuthor: boolean
+  ): Promise<Comment> => {
+    return await this.Model.create({
+      PostId: postId,
+      AuthorId: authorId,
+      Content: content,
+      IsPostAuthor: isPostAuthor,
+    });
+  };
+
+  /**
+   * Get all comments for post id
+   * @param itemCount
+   * @returns
+   */
+  public getComments = async (postId: string): Promise<Comment[]> => {
+    return await this.Model.find({ PostId: postId });
+  };
+
+  /**
+   * Method to remove a comment
+   * @param user1
+   * @param user2
+   */
+  public RemoveComment = async (
+    jwtAuthorId: string,
+    commentId: string
+  ): Promise<void> => {
+    const comment = await this.Model.findById({ commentId });
+
+    if (comment.AuthorId !== jwtAuthorId) {
+      throw new Error("Unauthorised");
+    }
+
+    const result = await this.Model.findByIdAndDelete(commentId);
+    if (result === null) {
+      throw new Error("Could not find comment.");
+    }
+
+    return result;
+  };
+
+  /**
+   * Like a comment.
+   * @param id
+   * @returns
+   */
+  public LikeOrUnlikeComment = async (
+    commentId: string,
+    likerId: string,
+    like: boolean
+  ): Promise<Comment> => {
+    const existingComment = await this.Model.findById(commentId);
+    const existingLikes = existingComment.LikerIds;
+
+    if (existingComment === null) {
+      throw new Error("Could not find comment");
+    }
+
+    if (like && existingLikes.includes(likerId)) {
+      throw new Error("Can't Like a comment twice!");
+    }
+
+    if (!like && !existingLikes.includes(likerId)) {
+      throw new Error("Comment not Liked!");
+    }
+
+    if (like) {
+      existingLikes.push(likerId);
+    } else {
+      existingLikes.splice(existingLikes.indexOf(likerId), 1);
+    }
+
+    const result = await this.Model.findByIdAndUpdate(commentId, {
+      LikerIds: existingLikes,
+    });
+
+    if (result === null) {
+      throw new Error("Could not find comment");
+    }
+
+    return result;
+  };
+}
+
+export default new CommentDataStore("Comment", CommentSchema);

backend-services/comment-service-2/src/Datastores/DataStore.ts

+import mongoose, { Model, Schema } from 'mongoose'
+
+/**
+ * Defines common datastore functionality
+ */
+export abstract class DataStore<T> {
+
+  /**
+   * Mongoose model pertaining to the datastore type
+   */
+   public Model: Model<any>
+
+   constructor (modelName: string, schema: Schema) {
+     this.Model = mongoose.model(modelName, schema)
+   }
+
+   /**
+   * Finds a single item matching a given query
+   * @param query
+   * @returns
+   */
+    public GetItem = async (query: any): Promise<T | null> => {
+      return await this.Model.findOne(query)
+    }
+}
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