How to check if post has been liked by current user

Question

How would i be able to check if the current user liked the post or not. Ideally this would be similar to liking a post on instagram. The heart is filled red indicating that YOU liked it.

how would i be able to add a similar functionality for the backend.

I know the backend would have a boolean that indicates a user has like there own post. I'm using sequelize, given my model, what should i do to make this functionality work.

Ideally the liked column in post should indicate if i liked post or not.

req.session.user.id gets the current user.

post.controller

 getPosts: async (req: Request, res: Response) => {
    await models.Post.findAll({
      include: [
        { model: models.User, as: "author", attributes: ["username"] },
        { model: models.Likes }
      ],
      order: [["createdAt", "DESC"]],
      limit: 6
    }).then(posts => {
      res.json(posts);
    });
  },

Post (model)

"use strict";
module.exports = (sequelize, DataTypes) => {
    var Post = sequelize.define("Post", {
        title: DataTypes.STRING,
        postContent: DataTypes.STRING,
        liked: {
            type: DataTypes.BOOLEAN,
            allowNull: false,
            defaultValue: false
        },
        likeCounts: {
            type: DataTypes.INTEGER,
            allowNull: false,
            defaultValue: 0
        },
        authorId: DataTypes.INTEGER
    }, {});
    Post.associate = function (models) {
        Post.belongsTo(models.User, {
            as: "author",
            foreignKey: "authorId",
            onDelete: "CASCADE"
        });
        Post.hasMany(models.Likes, {
            foreignKey: "resourceId",
            timestamps: false,
            targetKey: "id",
            onDelete: "CASCADE"
        });
    };
    Post.prototype.likedByMe = postId => { };
    return Post;
};
//# sourceMappingURL=post.js.map

Like (model)

"use strict";
module.exports = (sequelize, DataTypes) => {
    var Likes = sequelize.define("Likes", {
        userId: DataTypes.INTEGER,
        resourceId: DataTypes.INTEGER,
        likeByMe: {
            type: DataTypes.BOOLEAN,
            defaultValue: false,
            allowNull: false
        }
    });
    Likes.associate = function (models) {
        // associations can be defined here
        Likes.belongsTo(models.User, {
            foreignKey: "userId",
            timestamps: false,
            onDelete: "CASCADE"
        });
        Likes.belongsTo(models.Post, {
            foreignKey: "resourceId",
            timestamps: false,
            onDelete: "CASCADE",
            targetKey: "id"
        });
    };
    return Likes;
};
//# sourceMappingURL=likes.js.map

Answer 1

something like

const iLikeIt = Like.findOne({ where: {
    resourceId: postId,
    userId: req.session.user.id,
}})
if (iLikeIt) {
    // i liked it
} else {
    // i didn't like it
}