48 lines
1.1 KiB
Markdown
48 lines
1.1 KiB
Markdown
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# Rewrite "rethrow" with async/await
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Below you can find the "rethrow" example. Rewrite it using `async/await` instead of `.then/catch`.
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And get rid of the recursion in favour of a loop in `demoGithubUser`: with `async/await` that becomes easy to do.
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```js run
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class HttpError extends Error {
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constructor(response) {
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super(`${response.status} for ${response.url}`);
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this.name = 'HttpError';
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this.response = response;
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}
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}
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function loadJson(url) {
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return fetch(url)
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.then(response => {
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if (response.status == 200) {
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return response.json();
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} else {
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throw new HttpError(response);
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}
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});
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}
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// Ask for a user name until github returns a valid user
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function demoGithubUser() {
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let name = prompt("Enter a name?", "iliakan");
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return loadJson(`https://api.github.com/users/${name}`)
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.then(user => {
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alert(`Full name: ${user.name}.`);
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return user;
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})
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.catch(err => {
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if (err instanceof HttpError && err.response.status == 404) {
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alert("No such user, please reenter.");
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return demoGithubUser();
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} else {
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throw err;
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}
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});
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}
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demoGithubUser();
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```
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