Meta: Reorganize utility functions (#3110)

1 files changed, 210 insertions, 0 deletions

diff --git a/source/github-helpers/api.ts b/source/github-helpers/api.ts
new file mode 100644
index 00000000..98849238
--- /dev/null
+++ b/source/github-helpers/api.ts
@@ -0,0 +1,210 @@
+/*
+These will throw `RefinedGitHubAPIError` if something goes wrong or if it's a 404.
+Probably don't catch them so they will appear in the console
+next to the name of the feature that caused them.
+
+Usage:
+
+import * as api from '../github-helpers/api';
+const user = await api.v3(`users/${username}`);
+const data = await api.v4('{user(login: "user") {name}}');
+
+Returns:
+a Promise that resolves into an object.
+
+If the response body is empty, you'll receive an object like {status: 200}
+
+The second argument is an options object,
+it lets you define accept error HTTP codes as a valid response, like:
+
+{
+	ignoreHTTPStatus: true
+}
+
+so the call will not throw an error but it will return as usual.
+ */
+
+import mem from 'mem';
+import {JsonObject, AsyncReturnType} from 'type-fest';
+
+import optionsStorage from '../options-storage';
+
+type JsonError = {
+	message: string;
+};
+
+interface GraphQLResponse {
+	message?: string;
+	data?: JsonObject;
+	errors?: JsonError[];
+}
+
+interface RestResponse extends AnyObject {
+	httpStatus: number;
+	headers: Headers;
+	ok: boolean;
+}
+
+export const escapeKey = (value: string | number): string => '_' + String(value).replace(/[ ./-]/g, '_');
+
+export class RefinedGitHubAPIError extends Error {
+	constructor(...messages: string[]) {
+		super(messages.join('\n'));
+	}
+}
+
+const settings = optionsStorage.getAll();
+
+const api3 = location.hostname === 'github.com' ?
+	'https://api.github.com/' :
+	`${location.origin}/api/v3/`;
+const api4 = location.hostname === 'github.com' ?
+	'https://api.github.com/graphql' :
+	`${location.origin}/api/graphql`;
+
+interface GHRestApiOptions {
+	ignoreHTTPStatus?: boolean;
+	method?: 'GET' | 'POST' | 'PUT';
+	body?: undefined | JsonObject;
+	headers?: HeadersInit;
+	json?: boolean;
+}
+
+interface GHGraphQLApiOptions {
+	allowErrors?: boolean;
+}
+
+const v3defaults: GHRestApiOptions = {
+	ignoreHTTPStatus: false,
+	method: 'GET',
+	body: undefined,
+	json: true
+};
+
+const v4defaults: GHGraphQLApiOptions = {
+	allowErrors: false
+};
+
+export const v3 = mem(async (
+	query: string,
+	options: GHRestApiOptions = v3defaults
+): Promise<RestResponse> => {
+	const {ignoreHTTPStatus, method, body, headers, json} = {...v3defaults, ...options};
+	const {personalToken} = await settings;
+
+	if (query.startsWith('/')) {
+		throw new TypeError('The query parameter must not start with a slash.');
+	}
+
+	const url = new URL(query, api3);
+	const response = await fetch(url.href, {
+		method,
+		body: body && JSON.stringify(body),
+		headers: {
+			'User-Agent': 'Refined GitHub',
+			Accept: 'application/vnd.github.v3+json',
+			...headers,
+			...personalToken && {Authorization: `token ${personalToken}`}
+		}
+	});
+	const textContent = await response.text();
+	const apiResponse = json ? JSON.parse(textContent) : {textContent};
+
+	if (response.ok || ignoreHTTPStatus) {
+		return Object.assign(apiResponse, {
+			httpStatus: response.status,
+			headers: response.headers,
+			ok: response.ok
+		});
+	}
+
+	throw await getError(apiResponse);
+}, {
+	cacheKey: JSON.stringify
+});
+
+export const v3paginated = async function * (
+	query: string,
+	options?: GHRestApiOptions
+): AsyncGenerator<AsyncReturnType<typeof v3>> {
+	while (true) {
+		// eslint-disable-next-line no-await-in-loop
+		const response = await v3(query, options);
+		yield response;
+
+		[, query] = /<([^>]+)>; rel="next"/.exec(response.headers.get('link')!) ?? [];
+		if (!query) {
+			return;
+		}
+	}
+};
+
+export const v4 = mem(async (
+	query: string,
+	options: GHGraphQLApiOptions = v4defaults
+): Promise<AnyObject> => {
+	const {personalToken} = await settings;
+
+	if (/^(query )?{/.test(query.trimStart())) {
+		throw new TypeError('`query` should only be what’s inside \'query {...}\', like \'user(login: "foo") { name }\', but is \n' + query);
+	}
+
+	if (!personalToken) {
+		throw new Error('Personal token required for this feature');
+	}
+
+	const response = await fetch(api4, {
+		headers: {
+			'User-Agent': 'Refined GitHub',
+			Authorization: `bearer ${personalToken}`
+		},
+		method: 'POST',
+		body: JSON.stringify({query: `{${query}}`})
+	});
+
+	const apiResponse: GraphQLResponse = await response.json();
+
+	const {
+		data = {},
+		errors = []
+	} = apiResponse;
+
+	if (errors.length > 0 && !options.allowErrors) {
+		throw new RefinedGitHubAPIError('GraphQL:', ...errors.map(error => error.message));
+	}
+
+	if (response.ok) {
+		return data;
+	}
+
+	throw await getError(apiResponse as JsonObject);
+}, {
+	cacheKey: JSON.stringify
+});
+
+export async function getError(apiResponse: JsonObject): Promise<RefinedGitHubAPIError> {
+	const {personalToken} = await settings;
+
+	if ((apiResponse.message as string)?.includes('API rate limit exceeded')) {
+		return new RefinedGitHubAPIError(
+			'Rate limit exceeded.',
+			personalToken ?
+				'It may be time for a walk! 🍃 🌞' :
+				'Set your token in the options or take a walk! 🍃 🌞'
+		);
+	}
+
+	if (apiResponse.message === 'Bad credentials') {
+		return new RefinedGitHubAPIError(
+			'The token seems to be incorrect or expired. Update it in the options.'
+		);
+	}
+
+	return new RefinedGitHubAPIError(
+		'Unable to fetch.',
+		personalToken ?
+			'Ensure that your token has access to this repo.' :
+			'Maybe adding a token in the options will fix this issue.',
+		JSON.stringify(apiResponse, null, '\t') // Beautify
+	);
+}