index.js

/******************************************************************************
 *
 * Copyright (c) 2017, the Perspective Authors.
 *
 * This file is part of the Perspective library, distributed under the terms of
 * the Apache License 2.0.  The full license can be found in the LICENSE file.
 *
 */

const { WebSocketServer, table } = require("@finos/perspective");
const { read_stdin, open_browser } = require("./utils.js");
const fs = require("fs");
const path = require("path");
const program = require("commander");
const puppeteer = require("puppeteer");

/**
 * Convert data from one format to another.
 *
 * @param {*} filename
 * @param {*} options
 */
async function convert(filename, options) {
    let file;
    if (filename) {
        file = fs.readFileSync(filename).toString();
    } else {
        file = await read_stdin();
    }
    try {
        file = JSON.parse(file);
    } catch {}
    let tbl = await table(file);
    let view = await tbl.view();
    let out;
    options.format = options.format || "arrow";
    if (options.format === "csv") {
        out = await view.to_csv();
    } else if (options.format === "columns") {
        out = JSON.stringify(await view.to_columns());
    } else if (options.format === "json") {
        out = JSON.stringify(await view.to_json());
    } else {
        out = await view.to_arrow();
    }
    if (options.format === "arrow") {
        if (options.output) {
            fs.writeFileSync(options.output, Buffer.from(out), "binary");
        } else {
            console.log(Buffer.from(out).toString());
        }
    } else {
        if (options.output) {
            fs.writeFileSync(options.output, out);
        } else {
            console.log(out);
        }
    }
    view.delete();
    tbl.delete();
}

/**
 * Host a Perspective on a web server.
 *
 * @param {*} filename
 * @param {*} options
 */
async function host(filename, options) {
    let files = [path.join(__dirname, "..", "html")];
    if (options.assets) {
        files = [options.assets, ...files];
    }
    const server = new WebSocketServer({
        assets: files,
        port: options.port,
        host_psp: true,
    });
    let file;
    if (filename) {
        file = await table(fs.readFileSync(filename).toString());
    } else {
        file = await read_stdin();
    }
    server.host_table("data_source_one", file);
    if (options.open) {
        const browser = await puppeteer.launch({
            headless: false,
            defaultViewport: null,
            args: [
                "--incognito",
                "--noerrdialogs",
                "--disable-translate",
                "--no-first-run",
                "--fast",
                "--fast-start",
                "--disable-infobars",
                "--window-size=1200,800",
                "--disable-features=TranslateUI",
                "--disk-cache-dir=/dev/null",
                `--app=http://localhost:${options.port}/`,
            ],
        });

        const pages = await browser.pages();

        const page = pages[0];
        page.on("close", () => {
            browser.close();
            process.exit(0);
        });
    }

    return server;
}

module.exports.host = host;

program
    .version(
        JSON.parse(
            fs
                .readFileSync(path.join(__dirname, "..", "..", "package.json"))
                .toString()
        ).version
    )
    .description(
        "A convenient command-line client for Perspective.js.  Can convert between Perspective supported format, or host a local web server."
    )
    .action(() => program.help());

program
    .command("convert [filename]")
    .description(
        "Convert a file into a new format.  Reads from STDIN if no filename is provided."
    )
    .option(
        "-f, --format <format>",
        "Which output format to use:  arrow, csv, columns, json.",
        /^(arrow|json|columns|csv)$/i,
        "arrow"
    )
    .option(
        "-o, --output <filename>",
        "Filename to write to.  If not supplied, writes to STDOUT."
    )
    .action(convert);

program
    .command("host [filename]")
    .description(
        "Host a file on a local Websocket/HTTP server using a server-side Perspective.  Reads from STDIN if no filename is provided"
    )
    .option(
        "-p, --port <port>",
        "Which port to bind to.",
        (x) => parseInt(x),
        8080
    )
    .option("-a, --assets <path>", "Host from a working directory")
    .option("-o, --open", "Open a browser automagically.")
    .action(host);

if (require.main && !process.argv.slice(2).length) {
    program.help();
}