added example

src/asyncawait.ts

@@ -0,0 +1,57 @@
+import { delay } from "https://deno.land/std@0.202.0/async/delay.ts";
+
+
+async function downloadFilesWithDelay(urls: string[]): Promise<string[]>{
+    let ret: string[] = [];
+    for(const url of urls){
+        await delay(1000);
+        const resp = await fetch(url);
+        ret.push(await resp.text());
+    }
+    return ret;
+}
+
+async function downloadFile(): Promise<void> {
+    const url = "https://didier-ahuntsic.gitlab.io/cours-420-317-ah/data/grades.json";
+    const resp = await fetch(url);
+    const payload = await resp.json();
+    let ser = JSON.stringify(payload);
+    await Deno.writeTextFile("grades.json", ser);
+}
+
+type Index = {links: string[]};
+
+async function getIndex(url: string): Promise<Index>{
+    const resp = await fetch(url);
+    return (await resp.json()) as Index;
+}
+
+async function getEachUrl(links: string[]): Promise<string> {
+    const ret : string[] = [];
+    for(const url of links){
+        const resp = await fetch(url);
+        ret.push(await resp.json());
+    }
+    return ret;
+}
+
+async function downloadSubUrls(url: string): Promise<string>{
+    const index = await getIndex(url);
+    return await getEachUrl(index.links);
+}
+
+// const url = "https://didier-ahuntsic.gitlab.io/cours-420-317-ah/data/exo-index.json";
+// const ret = await downloadSubUrls(url);
+// console.log(ret.length)
+
+async function download2InParallel():Promise<string[]>{
+    const url1 = "http://httpbin.org/delay/3";
+    const url2 = "http://httpbin.org/delay/3";
+    const pResp1 =  fetch(url1);
+    const pResp2 =  fetch(url2);
+    await Promise.all([pResp1, pResp2]);
+
+}
+
+
+