Added book getting by hash in service worker

src/serviceWorker/db.ts

@@ -23,3 +23,9 @@ export const saveBook = async (book: BookT) =>
  * Returns all books saved in IndexedDB
  */
 export const getBooks = async () => (await openDB()).getAll("Books");
+
+/**
+ * Gets book from IndexedDB by hash
+ */
+export const getBook = async (hash: string) =>
+  (await openDB()).get("Books", hash);

src/serviceWorker/fetchHandlers.ts

@@ -1,4 +1,4 @@
-import { getBooks, saveBook } from "./db";
+import { getBook, getBooks, saveBook } from "./db";
 
 export interface PathHandler {
   /** Path start for handler */
@@ -43,3 +43,13 @@ export const handleBooks = async () => {
 
   return new Response(JSON.stringify(list));
 };
+
+/**
+ * Gets book from database
+ */
+export const handleBook = async (request: Request, hash: string) => {
+  const book = await getBook(hash);
+  if (book) return new Response(JSON.stringify(book));
+
+  return new Response("No such book :(");
+};

src/serviceWorker/index.ts

@@ -2,10 +2,12 @@ import { fromCache, precache } from "./cache";
 import { openDB as createDB } from "./db";
 import {
   handle,
+  handleBook,
   handleBooks,
   handleBookUpload,
   PathHandler,
 } from "./fetchHandlers";
+import { getHash } from "./utils";
 
 declare const self: ServiceWorkerGlobalScope;
 
@@ -21,8 +23,9 @@ self.addEventListener("fetch", (event) => {
   const path = new URL(request.url).pathname;
 
   const handlers: PathHandler[] = [
-    { path: "/upload", getResponse: () => handleBookUpload(request) },
     { path: "/list", getResponse: () => handleBooks() },
+    { path: "/book/", getResponse: () => handleBook(request, getHash(path)) },
+    { path: "/upload", getResponse: () => handleBookUpload(request) },
     { path: "", getResponse: () => fromCache(request) },
   ];
 

src/serviceWorker/utils.ts

@@ -0,0 +1,9 @@
+/**
+ * Gets hash string from book path
+ */
+export const getHash = (path: string) => {
+  let hashLength = path.length - "/book/".length;
+  if (path.endsWith("/")) hashLength--;
+
+  return path.substr("/book/".length, hashLength);
+};