typed-environment-loader/dist/loader.js

typed-environment-loader is a lightweight utility for loading environment variables in a typed manner, ensuring type safety and consistency in your Node.js applications.

"use strict";
var __values = (this && this.__values) || function(o) {
    var s = typeof Symbol === "function" && Symbol.iterator, m = s && o[s], i = 0;
    if (m) return m.call(o);
    if (o && typeof o.length === "number") return {
        next: function () {
            if (o && i >= o.length) o = void 0;
            return { value: o && o[i++], done: !o };
        }
    };
    throw new TypeError(s ? "Object is not iterable." : "Symbol.iterator is not defined.");
};
var __read = (this && this.__read) || function (o, n) {
    var m = typeof Symbol === "function" && o[Symbol.iterator];
    if (!m) return o;
    var i = m.call(o), r, ar = [], e;
    try {
        while ((n === void 0 || n-- > 0) && !(r = i.next()).done) ar.push(r.value);
    }
    catch (error) { e = { error: error }; }
    finally {
        try {
            if (r && !r.done && (m = i["return"])) m.call(i);
        }
        finally { if (e) throw e.error; }
    }
    return ar;
};
var __spreadArray = (this && this.__spreadArray) || function (to, from, pack) {
    if (pack || arguments.length === 2) for (var i = 0, l = from.length, ar; i < l; i++) {
        if (ar || !(i in from)) {
            if (!ar) ar = Array.prototype.slice.call(from, 0, i);
            ar[i] = from[i];
        }
    }
    return to.concat(ar || Array.prototype.slice.call(from));
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.EnvironmentLoader = void 0;
var debug_1 = require("./debug");
var errors_1 = require("./errors");
var parser_registry_1 = require("./parsers/parser-registry");
var EnvironmentLoader = (function () {
    function EnvironmentLoader(_schema, _env, config) {
        if (_env === void 0) { _env = process.env; }
        if (config === void 0) { config = {}; }
        var _this = this;
        var _a;
        this._schema = _schema;
        this._env = _env;
        this._debug = (0, debug_1.createDebugLogger)(this.constructor.name);
        this._parser = new parser_registry_1.ParserRegistry();
        this._config = {
            separator: config.separator || '__',
            prefix: config.prefix || '',
            transformEnvKey: config.transformEnvKey || (function (key) { return key.toUpperCase(); }),
            transformPath: config.transformPath || (function (path) { return path.join(_this._config.separator); }),
            defaultRequired: (_a = config.defaultRequired) !== null && _a !== void 0 ? _a : false
        };
    }
    EnvironmentLoader.prototype.load = function () {
        var e_1, _a;
        this._debug.info('Starting to load environment variables');
        var result = {};
        var stack = [{ schema: this._schema, result: result, path: [] }];
        while (stack.length > 0) {
            var current = stack.pop();
            this._debug.info('Processing schema', current.schema, 'at path', current.path);
            var entries = Object.entries(current.schema).reverse();
            try {
                for (var entries_1 = (e_1 = void 0, __values(entries)), entries_1_1 = entries_1.next(); !entries_1_1.done; entries_1_1 = entries_1.next()) {
                    var _b = __read(entries_1_1.value, 2), key = _b[0], config = _b[1];
                    var currentPath = __spreadArray(__spreadArray([], __read(current.path), false), [key], false);
                    var envKey = this.getEnvKey(config, currentPath);
                    this._debug.info('Processing key', key, 'with config', config, 'and envKey', envKey);
                    if (this.isSchemaItem(config)) {
                        current.result[key] = this.parseValue(config, currentPath, envKey);
                    }
                    else {
                        var nestedResult = {};
                        current.result[key] = nestedResult;
                        stack.push({
                            schema: config,
                            result: nestedResult,
                            path: currentPath
                        });
                    }
                }
            }
            catch (e_1_1) { e_1 = { error: e_1_1 }; }
            finally {
                try {
                    if (entries_1_1 && !entries_1_1.done && (_a = entries_1.return)) _a.call(entries_1);
                }
                finally { if (e_1) throw e_1.error; }
            }
        }
        this._debug.info('Finished loading environment variables');
        return result;
    };
    EnvironmentLoader.prototype.parseValue = function (schema, path, envKey) {
        var _a, _b;
        this._debug.info('Parsing value for envKey', envKey, 'at path', path);
        var envKeyTransformed = this._config.transformEnvKey(envKey);
        var value = (_a = this._env[envKeyTransformed]) === null || _a === void 0 ? void 0 : _a.trim();
        if (!value) {
            this._debug.warn('Value for envKey', envKey, 'is missing');
            var isRequired = (_b = schema.required) !== null && _b !== void 0 ? _b : this._config.defaultRequired;
            if (isRequired) {
                this._debug.warn('envKey', envKey, 'is required but missing, throwing error');
                throw new errors_1.EnvironmentMissingError(envKey, path);
            }
            this._debug.info('Using default value for envKey', envKey);
            return this.handleDefault(schema.default);
        }
        this._debug.info('Parsing value', value, 'for envKey', envKey);
        return this._parser.parse({ envKey: envKey, path: path, schema: schema, value: value }).value;
    };
    EnvironmentLoader.prototype.getEnvKey = function (config, path) {
        if ('name' in config && config.name) {
            return this._config.prefix + config.name;
        }
        return this._config.prefix + this._config.transformPath(path);
    };
    EnvironmentLoader.prototype.handleDefault = function (defaultValue) {
        return Array.isArray(defaultValue) ? __spreadArray([], __read(defaultValue), false) : defaultValue;
    };
    EnvironmentLoader.prototype.isSchemaItem = function (value) {
        return 'type' in value;
    };
    return EnvironmentLoader;
}());
exports.EnvironmentLoader = EnvironmentLoader;