add method Delete api

database.js

@@ -1,10 +1,10 @@
-const books = [{
+let books = [{
     ISBN:"1234BOOK",
     title:"Getting started with MERN",
     pubDate:"20201-07-07",
     language:"en",
     numPage:250,
-    author:[1, 2],
+    authors:[1, 2],
     publication:[1],
     category:["tech", "programing", "education", "triller"],
   },
@@ -14,7 +14,7 @@ const books = [{
     pubDate:"20201-07-07",
     language:"en",
     numPage:250,
-    author:[1, 2],
+    authors:[1, 2],
     publication:[2],
     category:["tech", "programing", "education", "triller"],
   }

index.js

@@ -291,6 +291,62 @@ booky.put("/publication/update/book/:isbn", (req, res) => {
      });
  });
 
+ /* 
+Route            /book/delete
+Discription      Delete a book
+Access           Public
+Parameter        isbn
+Method           DELETE
+*/
+booky.delete("/book/delete/:isbn", (req, res) => {
+
+    const updatedBookDatabase = database.books.filter(
+      (book) => book.ISBN !== req.params.isbn
+    );
+
+    database.books = updatedBookDatabase;
+    return res.json({ books: database.books });
+});
+
+ /* 
+Route            /book/delete/author
+Discription      Delete a book from publication
+Access           Public
+Parameter        isbn, author id
+Method           DELETE
+*/
+booky.delete("/book/delete/author/:isbn/:authorId", (req, res) => {
+    //update book database
+    database.books.forEach((book) => {
+        if(book.ISBN === req.params.isbn) {
+            const newAuthorList = book.authors.filter(
+                (author) => author !== parseInt(req.params.authorId)
+            );//convert string to no
+
+            book.authors = newAuthorList;
+            return;
+        }   
+    });
+
+    //update author database
+    database.author.forEach((author) => {
+        if(author.id === parseInt(req.params.authorId)) {
+            const newBooksList = author.books.filter(
+                (book) => book !== req.params.isbn
+            );
+
+          author.books = newBooksList;
+          return;
+        }
+    });
+
+    return res.json({ 
+        message: "author was deleted",
+        book: database.books, 
+        author: database.author, 
+    })
+});
+
 booky.listen(3000, () => console.log("Hey  server booting..."));
 
 //HTTP client -> helper who helps you to make http request

requirements.js

@@ -63,11 +63,11 @@
 
 // PUT
 // UPdate the publication name using it's id [Task] 🚀
-// update/add books to publications
+// update/add books to publications✅
 
 // DELETE
-// Delete the publication
-// delete a book from publication.
+// Delete the publication✅
+// delete a book from publication.✅
 
 
 //How the server serves the request