domotz-remote-pawn/src/setup/env.js

Domotz Agent

/**
 * This file is part of Domotz Agent.
 * Copyright (C) 2016  Domotz Ltd
 *
 * Domotz Agent is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Domotz Agent is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Domotz Agent.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Created by Tommaso Latini <tommaso@domotz.com> on 26/09/2015
 */

const DOMOTZ_ENV = process.platform === 'win32' ? require('path').join(process.env.ALLUSERSPROFILE, 'domotz', 'domotz.env') : '/etc/domotz.env';
const ENV_VAR_REGEXP = /\s*export ([\w\.\-]+)\s*=\s*["']?([^'"]*)?["']?\s*/;

var fs = require('fs');

function calculateNewEnvironmentValue(fileOverridesEnvironment, newValue, key, oldValue) {
    if (fileOverridesEnvironment) {
        if (newValue) {
            console.verbose('ENV - Variable %s to be replace with value %s', key, newValue);
            return newValue;
        } else {
            console.verbose('ENV - Keeping old %s value %s, a new one was not found', key, oldValue);
            return oldValue;
        }
    } else {
        if (oldValue) {
            console.verbose('ENV - Keeping existing old %s value %s', key, oldValue);
            return oldValue;
        } else {
            console.verbose('ENV - Setting value for variable %s=%s', key, newValue);
            return newValue;
        }
    }
}
module.exports.load = function (envFile, fileOverridesEnvironment) {
    var env = process.env;
    // When true, the file contents override the environment values, e.g. when env file is specified
    // on command-line, its settings should override the current environment.
    // By default, the environment values, when present, should be kept.
    fileOverridesEnvironment = fileOverridesEnvironment || false;

    // Configure the environment [For OpenWRT]
    // N.B. It's ok also for the other architectures
    var lines = [];
    try {
        var content = fs.readFileSync(envFile || DOMOTZ_ENV, { encoding: 'utf8' });
        lines = content.toString().split('\n');
    } catch (error) {
        console.error('Environment configuration: ' + error.message);
        console.info(error.message);
    }

    console.debug('ENV - Old:\n%s', JSON.stringify(env, null, 2));

    lines.forEach(function (line) {
        var keyValueArr = line.match(ENV_VAR_REGEXP);
        if (keyValueArr !== null) {
            var key = keyValueArr[1],
                value = keyValueArr[2];
            console.silly('ENV - Process line "%s". Key [%s], Value "%s"', line, key, value);
            if (value) {
                // Remove processes
                if (value.charAt(0) === '`' || value.slice(0, 2) === '$(') {
                    console.verbose("ENV - It's a bash process: support for execution not available... Skip");
                    return;
                }

                // Expand newlines in quoted values
                var len = value ? value.length : 0;
                if (len > 0 && value.charAt(0) === '"' && value.charAt(len - 1) === '"') {
                    value = value.replace(/\\n/gm, '\n');
                }

                var newValue = value.replace(/\${[A-Z_]+}/g, function (oldValue) {
                    return process.env[/\$[{]?([A-Z_]+)[}]?/.exec(oldValue)[1]];
                });
                env[key] = calculateNewEnvironmentValue(fileOverridesEnvironment, newValue, key, env[key]);
            } else {
                console.verbose('ENV - Value not available... Skip');
            }
        }
    });

    console.debug('ENV - New:\n%s', JSON.stringify(env, null, 2));

    if (process.env.DPLATFORM === 'raspberry') {
        //required when executing external scripts that use tput
        process.env.TERM = process.env.TERM || 'xterm-256color';
    }
};

//used for unit tests only
module.exports.get = function () {
    return process.env;
};