Added liking and security measures

features/posts/GET_post_detail.js

@@ -0,0 +1,58 @@
+const express = require("express");
+const router = express.Router();
+const pool = require("../../db");
+const { strictInput } = require("../../middleware/strict_input");
+const { areFriends } = require("../relations/friend_graph");
+const { likeDataForPosts } = require("./post_graph");
+
+async function getPostDetail(req, res) {
+  try {
+    const { id } = req.params;
+    const postId = Number(id);
+    if (!Number.isInteger(postId) || postId <= 0) {
+      return res.status(400).send("Invalid post id");
+    }
+    const { rows } = await pool.query(
+      `SELECT p.id, p.title, p.text, p.author_id, people.username AS author_username, p.image_link, p.created_at, people.private AS author_private
+       FROM posts p
+       LEFT JOIN people ON people.id = p.author_id
+       WHERE p.id = $1 AND p.active = true`,
+      [postId],
+    );
+    if (rows.length === 0) {
+      return res.status(404).send("Post not found");
+    }
+    const post = rows[0];
+    if (
+      post.author_private &&
+      Number(post.author_id) !== req.user.id &&
+      !(await areFriends(req.user.id, post.author_id))
+    ) {
+      return res.status(404).send("Post not found");
+    }
+    const { author_private, ...publicPost } = post;
+    const likeData = (await likeDataForPosts(req.user.id, [post.id])).get(
+      Number(post.id),
+    ) ?? { like_count: 0, liked_by_me: false };
+    return res
+      .status(200)
+      .json({
+        ...publicPost,
+        comments: [],
+        like_count: likeData.like_count,
+        liked_by_me: likeData.liked_by_me,
+      });
+  } catch (err) {
+    console.error("post detail query failed", {
+      message: err.message,
+      code: err.code,
+      detail: err.detail,
+      hint: err.hint,
+    });
+    return res.status(500).send("Post could not be retrieved, request failed");
+  }
+}
+
+router.get("/:id", strictInput(), getPostDetail);
+
+module.exports = router;