generate-changelog.ts

/*
 * Copyright 2017 Palantir Technologies, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Generates entries for CHANGELOG.md from pull requests
 *
 * Reads changelog entries from pull requests merged since the last release tag.
 * Changelog entries are lines within the first PR comment that matches /^\[[a-z\-]+\]/ like `[new-rule]` and `[bugfix]`
 */

// tslint:disable:no-console

import GitHubApi = require("github");
import * as fs from "fs";
import * as os from "os";
import * as path from "path";

import { camelize } from "../lib/utils";

const github = new GitHubApi({
    host: "api.github.com",
    protocol: "https",
    timeout: 5000,
});

const repoInfo = {
    owner: "palantir",
    repo: "tslint",
};

const tokenFile = path.join(os.homedir(), "github_token.txt");

// authenticate
const auth: GitHubApi.Auth = {
    token: fs.readFileSync(tokenFile, "utf8").toString().trim(),
    type: "oauth",
};
console.log("Using OAuth token " + auth.token + "\n");

// process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0"; // ignores TLS certificate error
github.authenticate(auth);

const commits: ICommit[] = [];
github.repos.getLatestRelease(repoInfo).then((value) => {
    console.log("Getting commits " + value.tag_name + "..master");
    // get the commits between the most recent release and the head of master
    return github.repos.compareCommits({
        base: value.tag_name,
        head: "master",
        ...repoInfo,
    });
}).then((value) => {
    // for each commit, get the PR, and extract changelog entries
    const promises: Array<Promise<any>> = [];
    for (const commitInfo of value.commits) {
        const commit: ICommit = {
            fields: [],
            sha: commitInfo.sha,
            submitter: commitInfo.commit.author.name != null ? commitInfo.commit.author.name : commitInfo.author.login,
            title: commitInfo.commit.message,
        };
        commits.push(commit);

        // check for a pull request number in the commit title
        const match = (commitInfo.commit.message as string).match(/\(#(\d+)\)/);
        if (match && match.length > 1) {
            commit.pushRequestNum = Number.parseInt(match[1], 10);

            // get the PR text
            promises.push(github.issues.get({
                number: commit.pushRequestNum,
                ...repoInfo,
            }).then((comment) => {
                // extract the changelog entries
                const lines = (comment.body as string).split("\r\n");
                for (const line of lines) {
                    const fieldMatch = line.match(/^(\[[a-z\-]+\])/);
                    if (fieldMatch) {
                        commit.fields.push({
                            tag: fieldMatch[1],
                            text: addLinks(line) + " (#" + commit.pushRequestNum + ")",
                        });
                    }
                }
            }));
        }

    }
    return Promise.all(promises);
}).then(() => {
    const entries: IField[] = [];
    const noFields: string[] = [];
    const contributors = new Set<string>();
    for (const commit of commits) {
        if (commit.fields.length > 0) {
            for (const field of commit.fields) {
                if (field.tag !== "[no-log]") {
                    entries.push(field);
                }
            }
        } else {
            noFields.push(commit.title);
        }
        contributors.add(commit.submitter);
    }
    entries.sort((a, b) => {
        return a.tag.localeCompare(b.tag);
    });

    console.log("\n---- formatted changelog entries: ----");
    for (const entry of entries) {
        console.log("- " + entry.text);
    }

    console.log("\n---- PRs with missing changelog entries: ----");
    for (const missing of noFields) {
        console.log("- " + missing.replace(/[\r\n]+/, "\r\n    "));
    }

    console.log("\n---- thanks ----");
    console.log("Thanks to our contributors!");
    contributors.forEach((contributor) => {
        console.log("- " + contributor);
    });
}).catch((error) => {
    console.log("Error:" + error);
});

const cache = new Map<string, boolean>();

function isRule(ruleName: string): boolean {
    let result = cache.get(ruleName);
    if (result === undefined) {
        result = fs.existsSync(`./src/rules/${camelize(ruleName)}Rule.ts`);
        cache.set(ruleName, result);
    }
    return result;
}

/** Replace rule names with links to the docs website */
function addLinks(text: string): string {
    let result = "";
    let lastIndex = 0;
    // match everything that looks like a rule name and is enclosed in backticks
    const regex = /`([a-z][-a-z]*[a-z])+`/g;
    let match = regex.exec(text);
    while (match !== null) {
        if (isRule(match[1])) {
            result += text.slice(lastIndex, match.index) + `[${match[0]}](https://palantir.github.io/tslint/rules/${match[1]}/)`;
            lastIndex = regex.lastIndex;
        }
        match = regex.exec(text);
    }
    return result + text.slice(lastIndex);
}

interface IField {
    tag: string;
    text: string;
}

interface ICommit {
    pushRequestBody?: string;
    pushRequestNum?: number;
    submitter: string;
    sha: string;
    title: string;
    fields: IField[];
}