sourcebit-target-next/lib/data-client.js

A Sourcebit target plugin for Next.js

const fse = require('fs-extra');
const _ = require('lodash');
const { DEFAULT_FILE_CACHE_PATH } = require('./consts');

class SourcebitDataClient {
    constructor() {
        // Every time getStaticPaths is called, the page re-imports all required
        // modules causing this singleton to be reconstructed loosing any in
        // memory cache.
        // https://github.com/zeit/next.js/issues/10933
    }

    async getData({ cacheFilePath } = {}) {
        // For now, we are reading the changes from filesystem until re-import
        // of this module will be fixed: https://github.com/zeit/next.js/issues/10933
        const resolvedCacheFilePath = cacheFilePath || process.env.SOURCEBIT_NEXT_FILE_CACHE_PATH || DEFAULT_FILE_CACHE_PATH;
        const cacheFileExists = new Promise((resolve, reject) => {
            const retryDelay = 500;
            const maxNumOfRetries = 10;
            let numOfRetries = 0;
            const checkPathExists = async () => {
                const pathExists = await fse.pathExists(resolvedCacheFilePath);
                if (!pathExists && numOfRetries < maxNumOfRetries) {
                    numOfRetries += 1;
                    console.log(
                        `error in sourcebitDataClient.getData(), cache file '${resolvedCacheFilePath}' was not found, waiting ${retryDelay}ms and retry #${numOfRetries}`
                    );
                    setTimeout(checkPathExists, retryDelay);
                } else if (!pathExists) {
                    reject(
                        new Error(
                            `sourcebitDataClient of the sourcebit-target-next plugin did not find '${resolvedCacheFilePath}' file. Please check that Sourcebit plugins (sourcebit.js) are configured and executed correctly.`
                        )
                    );
                } else {
                    resolve();
                }
            };
            checkPathExists();
        });

        await cacheFileExists;

        return new Promise((resolve, reject) => {
            // Cache file might be in the middle of being written, hence readJson might fail, so retry after a short delay.
            const retryDelay = 50;
            const maxNumOfRetries = 3;
            let numOfRetries = 0;
            const readJson = async () => {
                try {
                    const content = await fse.readJson(resolvedCacheFilePath);
                    resolve(content);
                } catch (err) {
                    if (numOfRetries < maxNumOfRetries) {
                        numOfRetries += 1;
                        console.log(
                            `error in sourcebitDataClient.getData(), cache file '${resolvedCacheFilePath}' was not parsed, waiting ${retryDelay}ms and retry #${numOfRetries}`
                        );
                        setTimeout(readJson, retryDelay);
                    } else {
                        reject(
                            new Error(
                                `sourcebitDataClient of the sourcebit-target-next plugin could not JSON parse the '${resolvedCacheFilePath}' file. Please check that other Sourcebit plugins are executed successfully.`
                            )
                        );
                    }
                }
            };
            readJson();
        });
    }

    async getStaticPaths() {
        const data = await this.getData();
        let paths = _.map(data.pages, (page) => page.path).filter(Boolean);
        if (process.env.NODE_ENV === 'development') {
            paths = paths.concat(_.map(paths, (pagePath) => pagePath + (pagePath !== '/' ? '/' : '')));
        }
        return paths;
    }

    async getStaticPropsForPageAtPath(pagePath) {
        const data = await this.getData();
        return this.getPropsFromCMSDataForPagePath(data, pagePath);
    }

    getPropsFromCMSDataForPagePath(data, pagePath) {
        if (_.isArray(pagePath)) {
            pagePath = pagePath.join('/');
        }
        pagePath = '/' + _.trim(pagePath, '/');
        const page = _.find(data.pages, { path: pagePath });
        return _.assign(page, data.props);
    }
}

module.exports.SourcebitDataClient = SourcebitDataClient;