boom

src/library.ts

@@ -0,0 +1,67 @@
+// @deno-types="npm:@types/express@4"
+import express, {Response, Request} from "npm:express@4";
+import bodyParser from "npm:body-parser@1.20.2";
+
+
+const app = express()
+app.use(bodyParser.json());
+
+
+type Book = {
+    isbn: string,
+    author: string,
+    title: string,
+    publicationYear: number,
+}
+
+const library : Book[] = [];
+
+function bookAlreadyExists(book: Book, library: Book[]): boolean{
+    for(const bookInLibrary of library){
+        if(book.isbn === bookInLibrary.isbn){
+            return true;
+        }
+    }
+    return false;
+}
+
+function isValidBook(maybeBook: any){
+    return Object.keys(maybeBook).length === 4
+        && "isbn" in maybeBook
+        && "author" in maybeBook
+        && "title" in maybeBook
+        && "publicationYear" in maybeBook;
+}
+
+app.get("/ping", (req: Request, res: Response): void => {
+    res.send("pongi");
+})
+
+app.get("/books", (req: Request, res: Response): void => {
+    const books = [];
+    for(const book of library){
+        books.push({isbn: book.isbn});
+    }
+    const ret = {
+        "books": books
+    }
+    res.send(ret);
+});
+
+app.post("/books", (req: Request, res: Response): void => {
+    const book = req.body;
+    if(!isValidBook(book) || bookAlreadyExists(book, library)){
+        res.status(400);
+        res.send({})
+        return;
+    }
+
+    library.push(book);
+    res.send(book);
+});
+
+
+const port = 3000
+app.listen(port, (): void => {
+    console.log(`Example app listening on port ${port}`)
+})

src/library_client.ts

@@ -0,0 +1,50 @@
+async function getPing(): Promise<void> {
+    const resp = await fetch("http://localhost:3000/ping")
+    const text = await resp.text()
+    console.log(text)
+}
+
+function extractIsbn(rawResponse: any): string[]{
+    const ret: string[] = [];
+    for(const elm of rawResponse.books){
+        ret.push(elm.isbn)
+    }
+    return ret;
+}
+
+async function getAllIsbn(){
+    const resp = await fetch("http://localhost:3000/books")
+    const ret = await resp.json();
+    return extractIsbn(ret);
+
+}
+
+async function createBook(isbn: string,
+                          author: string,
+                          title: string,
+                          publicationYear: number): Promise<boolean>{
+    const book = {isbn: isbn, author: author, title: title, publicationYear: publicationYear};
+
+    const resp = await fetch("http://localhost:3000/books", {
+        method: "POST",
+        headers: {
+            "Content-Type": "application/json",
+        },
+        body: JSON.stringify(book),
+    });
+    return resp.status < 300 && resp.status > 199;
+}
+
+async function createFourBooks(): Promise<void>{
+    await createBook("0000", "jk rolling", "harry potter I", 2004);
+    await createBook("1111", "jk rolling", "harry potter II", 2005);
+    await createBook("2222", "jk rolling", "harry potter III", 2006);
+    await createBook("3333", "jk rolling", "harry potter IV", 2007);
+}
+
+async function getCreateBook(): Promise<void> {
+    await createFourBooks();
+    console.log(await getAllIsbn());
+}
+
+await getCreateBook();