Added security policies to all endpoints and implemented file upload feature on posts

features/posts/EDIT_post.js

@@ -0,0 +1,100 @@
+const express = require("express");
+const router = express.Router();
+const pool = require("../../db");
+const { strictInput } = require("../../middleware/strict_input");
+const { authenticateToken } = require("../../middleware/authenticate_token");
+const {
+  handlePostUpload,
+  imageLinkForFile,
+  removeImageLink,
+  removeUploadedFile,
+} = require("../../middleware/post_upload");
+
+async function editPost(req, res) {
+  const id = req.query.id;
+  const { title, text, remove_image: removeImageValue } = req.body;
+  const removeImage = removeImageValue === "true";
+
+  if (removeImageValue !== undefined && !["true", "false"].includes(removeImageValue)) {
+    await removeUploadedFile(req.file);
+    return res.status(400).send("remove_image must be true or false");
+  }
+  if (req.file && removeImage) {
+    await removeUploadedFile(req.file);
+    return res.status(400).send("Choose either an image or remove_image=true");
+  }
+  if (title === "" || text === "") {
+    await removeUploadedFile(req.file);
+    return res.status(400).send("title and text cannot be empty");
+  }
+  if (title === undefined && text === undefined && !req.file && !removeImage) {
+    return res.status(400).send("At least one post field must be changed");
+  }
+
+  try {
+    const existing = await pool.query(
+      "SELECT id, image_link FROM posts WHERE id = $1 AND author_id = $2",
+      [id, req.user.id],
+    );
+    if (existing.rowCount === 0) {
+      await removeUploadedFile(req.file);
+      return res.status(404).send("Post not found or does not belong to you");
+    }
+
+    const oldImageLink = existing.rows[0].image_link;
+    const fields = [];
+    const values = [];
+    const addField = (field, value) => {
+      fields.push(`${field} = $${values.length + 1}`);
+      values.push(value);
+    };
+
+    if (title !== undefined) addField("title", title);
+    if (text !== undefined) addField("text", text);
+    if (req.file) addField("image_link", imageLinkForFile(req.file));
+    if (removeImage) addField("image_link", null);
+    values.push(id, req.user.id);
+
+    let updated;
+    try {
+      updated = await pool.query(
+        `UPDATE posts SET ${fields.join(", ")} WHERE id = $${values.length - 1} AND author_id = $${values.length} RETURNING id, title, text, author_id, image_link`,
+        values,
+      );
+    } catch (err) {
+      await removeUploadedFile(req.file);
+      throw err;
+    }
+
+    if (req.file || removeImage) {
+      await removeImageLink(oldImageLink).catch((err) => {
+        console.error("old post image could not be removed", { message: err.message });
+      });
+    }
+    return res.status(200).json(updated.rows[0]);
+  } catch (err) {
+    await removeUploadedFile(req.file);
+    console.error("database query failed", {
+      message: err.message,
+      code: err.code,
+      detail: err.detail,
+      hint: err.hint,
+      stack: err.stack,
+    });
+    return res.status(500).send("Post was not updated, request failed");
+  }
+}
+
+router.put(
+  "/",
+  authenticateToken,
+  handlePostUpload,
+  strictInput({
+    query: ["id"],
+    body: ["title", "text", "remove_image"],
+    cleanupUploadedFile: true,
+  }),
+  editPost,
+);
+
+module.exports = router;