helpx_html.pre.js

/*
 * Copyright 2018 Adobe. All rights reserved.
 * This file is licensed to you 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 REPRESENTATIONS
 * OF ANY KIND, either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */

/* eslint-disable no-param-reassign */

const _ = require('lodash/fp');
const { fetch } = require('@adobe/helix-fetch');

function collectMetadata(req, logger) {
  const options = {
    uri: `https://api.github.com/repos/${req.params.owner}/${
      req.params.repo
    }/commits?path=${req.params.path}&sha=${req.params.ref}`,
    headers: {
      'User-Agent': 'Request-Promise',
    },
  };

  logger.debug(`Fetching Git Metadata from ${options.uri}`);

  return fetch(options.uri, options)
    .then(async (response) => {
      if (!response.ok) {
        const e = new Error(`${response.status} - "${await response.text()}"`);
        e.statusCode = response.status;
        throw e;
      }
      const metadata = await response.json();
      logger.debug('Got git metadata');
      return metadata;
    })
    .catch((error) => {
      logger.error('Failed to get metadata', error);
      return {};
    });
}

/**
 * Extracts some committers data from the list of commits and appends the list to the content
 * @param {RequestContext} ctx Context
 */
function extractCommittersFromMetadata(meta) {
  const res = Object.values(meta)
    .filter((commit) => !!commit.author)
    .map((commit) => ({
      avatar_url: commit.author.avatar_url,
      display: `${commit.commit.author.name} | ${commit.commit.author.email}`,
    }));
  const uniq = _.uniqBy(JSON.stringify, res);
  return uniq;
}

function extractLastModifiedFromMetadata(meta = [], logger) {
  logger.debug('Getting last modified date from Git');
  const lastMod = meta.length > 0
    && meta[0].commit
    && meta[0].commit.author ? meta[0].commit.author.date : null;

  logger.debug(lastMod);
  return {
    raw: lastMod,
    display: lastMod ? new Date(lastMod) : 'Unknown',
  };
}

// the most compact way to write a pre.js:
//
// module.exports.pre is a function (taking next as an argument)
// that returns a function (with context, secrets, logger as arguments)
// that calls next (after modifying the context a bit)
module.exports.pre = (context, config) => {
  const { logger } = config;

  logger.debug('setting context path');
  context.content.contextPath = 'myinjectedcontextpath';

  logger.debug('collecting metadata');

  try {
    return collectMetadata(config.request, logger)
      .then((gitmeta) => {
        logger.debug('Metadata has arrived');
        context.content.gitmetadata = gitmeta;
        return gitmeta;
      })
      .then((gitmeta) => {
        const committers = extractCommittersFromMetadata(gitmeta, logger);
        context.content.committers = committers;
        return gitmeta;
      })
      .then((gitmeta) => {
        const lastMod = extractLastModifiedFromMetadata(gitmeta, logger);
        context.content.lastModified = lastMod;
      })
      .catch((e) => {
        logger.error(e);
        return { error: e };
      });
  } catch (e) {
    logger.error(e);
    return { error: e };
  }
};