@flowfuse/device-agent/index.js

An Edge Agent for running Node-RED instances deployed from the FlowFuse Platform

#!/usr/bin/env node
const semver = require('semver')
if (semver.lt(process.version, '14.0.0')) {
    console.log('FlowFuse Device Agent requires at least NodeJS v14.x')
    process.exit(1)
}

const TESTING = process.env.NODE_ENV === 'test'
const commandLineArgs = require('command-line-args')
const { info, warn } = require('./lib/log')
const { hasProperty } = require('./lib/utils')
const path = require('path')
const fs = require('fs')
const { AgentManager } = require('./lib/AgentManager')
const { WebServer } = require('./frontend/server')
const ConfigLoader = require('./lib/config')
const webServer = new WebServer()

function main (testOptions) {
    const pkg = require('./package.json')
    if (pkg.name === '@flowforge/flowforge-device-agent') {
        console.log(`
**************************************************************************
* The FlowFuse Device Agent is moving to '@flowfuse/device-agent' on npm *
* and 'flowfuse/device-agent' on DockerHub. Please upgrade to the new    *
* packages to ensure you continue to receive updates.                    *
* See https://flowfuse.com/docs/device-agent/install/ for details        *
**************************************************************************
`)
    }

    let options

    try {
        options = commandLineArgs(require('./lib/cli/args'), { camelCase: true })
        options = options._all
    } catch (err) {
        console.log(err.toString())
        console.log('Run with -h for help')
        quit()
    }
    if (options.version) {
        console.log(pkg.version)
        quit()
    }
    if (options.help) {
        console.log(require('./lib/cli/usage').usage())
        quit()
    }

    if (options.dir === '') {
        // No dir has been explicitly set, so we need to set the default.
        // 1. Use `/opt/flowforge-device` if it exists
        // 2. Otherwise use `/opt/flowfuse-device`
        if (fs.existsSync('/opt/flowforge-device')) {
            options.dir = '/opt/flowforge-device'
        } else {
            options.dir = '/opt/flowfuse-device'
        }
    }

    if (!path.isAbsolute(options.dir)) {
        options.dir = path.join(process.cwd(), options.dir)
    }

    // Require dir to be created
    if (!fs.existsSync(options.dir)) {
        try {
            fs.mkdirSync(options.dir, { recursive: true })
            if (!fs.existsSync(options.dir)) {
                throw new Error('Failed to create dir')
            }
        } catch (err) {
            const quitMsg = `Cannot create dir '${options.dir}'.
Please ensure the parent directory is writable, or set a different path with -d`
            quit(quitMsg, 20) // Exit Code 20 - Invalid dir
            // REF: https://slg.ddnss.de/list-of-common-exit-codes-for-gnu-linux/
            return
        }
    }

    // Locate the config file. Either the path exactly as specified,
    // or relative to dir

    let configFound = false
    const deviceFile1 = options.config || 'device.yaml'
    const deviceFile2 = path.join(options.dir, deviceFile1)
    if (fs.existsSync(deviceFile1)) {
        configFound = true
        options.deviceFile = deviceFile1
    } else if (fs.existsSync(deviceFile2)) {
        configFound = true
        options.deviceFile = deviceFile2
    }

    // If the config file is not found, set the `deviceFile` to the default value
    // ready for when the config file is created.
    if (!configFound) {
        options.deviceFile = deviceFile2 // deviceFile2 is the default value
    }

    delete options.config
    AgentManager.init(options)

    if (hasProperty(options, 'otc') || hasProperty(options, 'ffUrl')) {
        // Quick Connect mode
        if (!options.otc || options.otc.length < 8) {
            // 8 is the minimum length of an OTC
            // e.g. ab-cd-ef
            warn('Device setup requires parameter --otc to be 8 or more characters')
            quit(null, 2)
        }
        info('Entering Device setup...')
        if (!options.ffUrl) {
            warn('Device setup requires parameter --ff-url to be set')
            quit(null, 2)
        }
        AgentManager.quickConnectDevice().then((success) => {
            if (success) {
                const runCommandInfo = ['flowfuse-device-agent']
                if (options.dir !== '/opt/flowfuse-device') {
                    runCommandInfo.push(`-d ${options.dir}`)
                }
                info('Device setup was successful')
                info('To start the Device Agent with the new configuration run the following command:')
                info(runCommandInfo.join(' '))
                quit()
            } else {
                warn('Device setup was unsuccessful')
                quit(null, 2)
            }
        }).catch((err) => {
            quit(err.message, 2)
        })
        return
    }

    info('FlowFuse Device Agent')
    info('----------------------')

    if (options.ui) {
        info('Starting Web UI')
        if (!options.uiUser || !options.uiPass) {
            quit('Web UI cannot run without a username and password. These are set via with --ui-user and --ui-pass', 2)
        }
        const uiRuntime = Number(options.uiRuntime)
        if (isNaN(uiRuntime) || uiRuntime === Infinity || uiRuntime < 0) {
            quit('Web UI runtime must be 0 or greater', 2)
        }
        const opts = {
            port: options.uiPort || 1879,
            host: options.uiHost || '0.0.0.0',
            credentials: {
                username: options.uiUser,
                password: options.uiPass
            },
            runtime: uiRuntime,
            dir: options.dir,
            config: options.config,
            deviceFile: options.deviceFile
        }
        webServer.initialize(AgentManager, opts)
        webServer.start().then().catch((err) => {
            info(`Web UI failed to start: ${err.message}`)
        })
    }

    process.on('SIGINT', closeAgentAndQuit)
    process.on('SIGTERM', closeAgentAndQuit)
    process.on('SIGQUIT', closeAgentAndQuit)

    const parsedConfig = configFound && (ConfigLoader.parseDeviceConfigFile(options.deviceFile) || { valid: false })
    const isValidDeviceConfig = !!parsedConfig.valid

    if (isValidDeviceConfig) {
        AgentManager.startAgent()
    } else if (configFound && options.ui === true) {
        info(`Invalid config file '${options.deviceFile}'.`)
    } else if (!configFound && options.ui === true) {
        info(`No config file found at '${deviceFile1}' or '${deviceFile2}'`)
    } else {
        if (configFound) {
            quit(`Invalid config file '${options.deviceFile}': ${parsedConfig?.message || 'Unknown error'}'.`, 9) // Exit Code 9 - Invalid config file
        } else {
            quit(`No config file found at '${deviceFile1}' or '${deviceFile2}'`, 2) // No such file or directory
        }
    }

    function quit (msg, errCode = 0) {
        if (msg) { console.log(msg) }
        if (TESTING) {
            // don't exit if we are testing. Instead, call the onExit callback stub
            if (testOptions?.onExit) {
                testOptions.onExit(msg, errCode)
            }
        } else {
            process.exit(errCode)
        }
    }

    async function closeAgentAndQuit (msg, errCode = 0) {
        if (AgentManager) { await AgentManager.close() }
        quit(msg, errCode)
    }

    if (TESTING) {
        return {
            AgentManager,
            webServer,
            options: {
                ...ConfigLoader.defaults,
                ...options
            }
        }
    }
    return null
}

// if we are testing, export the main function so we can call it directly, otherwise call it now
if (TESTING) {
    module.exports = { main }
} else {
    main()
}