index.ts

import { getUserAgent } from "universal-user-agent";
import { Collection, HookCollection } from "before-after-hook";
import { request } from "@octokit/request";
import { graphql, withCustomRequest } from "@octokit/graphql";
import { createTokenAuth } from "@octokit/auth-token";

import {
  Constructor,
  OctokitOptions,
  OctokitPlugin,
  RequestParameters,
  ReturnTypeOf,
  UnionToIntersection,
} from "./types";
import { VERSION } from "./version";

export class Octokit {
  static VERSION = VERSION;
  static defaults<S extends Constructor<any>>(
    this: S,
    defaults: OctokitOptions | Function
  ) {
    const OctokitWithDefaults = class extends this {
      constructor(...args: any[]) {
        const options = args[0] || {};

        if (typeof defaults === "function") {
          super(defaults(options));
          return;
        }

        super(
          Object.assign(
            {},
            defaults,
            options,
            options.userAgent && defaults.userAgent
              ? {
                  userAgent: `${options.userAgent} ${defaults.userAgent}`,
                }
              : null
          )
        );
      }
    };

    return OctokitWithDefaults;
  }

  static plugins: OctokitPlugin[] = [];
  /**
   * Attach a plugin (or many) to your Octokit instance.
   *
   * @example
   * const API = Octokit.plugin(plugin1, plugin2, plugin3, ...)
   */
  static plugin<
    S extends Constructor<any> & { plugins: any[] },
    T extends OctokitPlugin[]
  >(this: S, ...newPlugins: T) {
    const currentPlugins = this.plugins;
    const NewOctokit = class extends this {
      static plugins = currentPlugins.concat(
        newPlugins.filter((plugin) => !currentPlugins.includes(plugin))
      );
    };

    return NewOctokit as typeof NewOctokit &
      Constructor<UnionToIntersection<ReturnTypeOf<T>>>;
  }

  constructor(options: OctokitOptions = {}) {
    const hook = new Collection();
    const requestDefaults: Required<RequestParameters> = {
      baseUrl: request.endpoint.DEFAULTS.baseUrl,
      headers: {},
      request: Object.assign({}, options.request, {
        hook: hook.bind(null, "request"),
      }),
      mediaType: {
        previews: [],
        format: "",
      },
    };

    // prepend default user agent with `options.userAgent` if set
    requestDefaults.headers["user-agent"] = [
      options.userAgent,
      `octokit-core.js/${VERSION} ${getUserAgent()}`,
    ]
      .filter(Boolean)
      .join(" ");

    if (options.baseUrl) {
      requestDefaults.baseUrl = options.baseUrl;
    }

    if (options.previews) {
      requestDefaults.mediaType.previews = options.previews;
    }

    if (options.timeZone) {
      requestDefaults.headers["time-zone"] = options.timeZone;
    }

    this.request = request.defaults(requestDefaults);
    this.graphql = withCustomRequest(this.request).defaults(requestDefaults);
    this.log = Object.assign(
      {
        debug: () => {},
        info: () => {},
        warn: console.warn.bind(console),
        error: console.error.bind(console),
      },
      options.log
    );
    this.hook = hook;

    // (1) If neither `options.authStrategy` nor `options.auth` are set, the `octokit` instance
    //     is unauthenticated. The `this.auth()` method is a no-op and no request hook is registered.
    // (2) If only `options.auth` is set, use the default token authentication strategy.
    // (3) If `options.authStrategy` is set then use it and pass in `options.auth`. Always pass own request as many strategies accept a custom request instance.
    // TODO: type `options.auth` based on `options.authStrategy`.
    if (!options.authStrategy) {
      if (!options.auth) {
        // (1)
        this.auth = async () => ({
          type: "unauthenticated",
        });
      } else {
        // (2)
        const auth = createTokenAuth(options.auth as string);
        // @ts-ignore  ¯\_(ツ)_/¯
        hook.wrap("request", auth.hook);
        this.auth = auth;
      }
    } else {
      const auth = options.authStrategy(
        Object.assign(
          {
            request: this.request,
          },
          options.auth
        )
      );
      // @ts-ignore  ¯\_(ツ)_/¯
      hook.wrap("request", auth.hook);
      this.auth = auth;
    }

    // apply plugins
    // https://stackoverflow.com/a/16345172
    const classConstructor = this.constructor as typeof Octokit;
    classConstructor.plugins.forEach((plugin) => {
      Object.assign(this, plugin(this, options));
    });
  }

  // assigned during constructor
  request: typeof request;
  graphql: typeof graphql;
  log: {
    debug: (message: string, additionalInfo?: object) => any;
    info: (message: string, additionalInfo?: object) => any;
    warn: (message: string, additionalInfo?: object) => any;
    error: (message: string, additionalInfo?: object) => any;
    [key: string]: any;
  };
  hook: HookCollection;

  // TODO: type `octokit.auth` based on passed options.authStrategy
  auth: (...args: unknown[]) => Promise<unknown>;

  [key: string]: any;
}