@graphprotocol/graph-cli/dist/watcher.js

CLI for building for and deploying to The Graph

import path from 'node:path';
import chokidar from 'chokidar';
export default class Watcher {
    onReady;
    onTrigger;
    onCollectFiles;
    onError;
    watcher;
    constructor(options) {
        const { onReady, onTrigger, onCollectFiles, onError } = options;
        this.onReady = onReady;
        this.onTrigger = onTrigger;
        this.onCollectFiles = onCollectFiles;
        this.onError = onError;
    }
    async watch() {
        // Collect files to watch
        const files = await this.onCollectFiles();
        // Initialize watcher
        this.watcher = chokidar.watch(files, {
            persistent: true,
            ignoreInitial: true,
            atomic: 500,
        });
        // Bind variables locally
        const watcher = this.watcher;
        const onTrigger = this.onTrigger;
        const onCollectFiles = this.onCollectFiles;
        const onError = this.onError;
        const onReady = this.onReady;
        watcher.on('ready', async () => {
            // Notify listeners that we're watching
            onReady();
            // Trigger once when ready
            onTrigger(undefined);
        });
        watcher.on('error', (error) => {
            onError(error);
        });
        watcher.on('all', async (_, file) => {
            try {
                // Collect watch all new files to watch
                const newFiles = await onCollectFiles();
                // Collect watched files, if there are any
                let watchedFiles = [];
                const watched = watcher.getWatched();
                watchedFiles = Object.keys(watched).reduce((files, dirname) => watched[dirname].reduce((files, filename) => {
                    files.push(path.resolve(path.join(dirname, filename)));
                    return files;
                }, files), []);
                const diff = (xs, ys) => ({
                    added: ys.filter((y) => !xs.includes(y)),
                    removed: xs.filter((x) => !ys.includes(x)),
                });
                // Diff previously watched files and new files; then remove and
                // add files from/to the watcher accordingly
                const filesDiff = diff(watchedFiles, newFiles);
                watcher.unwatch(filesDiff.removed);
                watcher.add(filesDiff.added);
                // Run the trigger callback
                onTrigger(file);
            }
            catch (e) {
                onError(e);
            }
        });
    }
    close() {
        if (this.watcher !== undefined) {
            this.watcher.close();
        }
    }
}