Add --save-config to persist flag-built configurations for reuse (#21)

Author: NikkelM

README.md

@@ -16,6 +16,7 @@ Get a list of all games currently available on Xbox Game Pass (Console, PC or EA
 - [Configuration](#configuration)
 - [Examples](https://github.com/NikkelM/Game-Pass-API/tree/main/examples)
 - [Feedback](#feedback)
+- [Disclaimer](#disclaimer)
 
 ## Installation
 
@@ -50,7 +51,7 @@ game-pass-api
 ```
 
 By default it reads `./config.json`; pass `--config <path>` to point at a different file.
-Run `game-pass-api --help` to see every command.
+Run `game-pass-api --help` to see every command, or `game-pass-api run --help` for the full list of flags.
 
 You can also run without a `config.json` at all, building the configuration entirely from flags:
 
@@ -59,8 +60,28 @@ game-pass-api --markets US,DE --platforms console,pc --properties productTitle,p
 ```
 
 Any option you omit uses its default.
+Add `--save-config` to also write the assembled configuration to a `config.json` (or `--save-config <path>`) so you can reuse or edit it later.
 Nested options such as images, pricing and user ratings are only available through a `config.json` or the wizard.
 
+### Command-line flags
+
+| Flag | Config key | Description |
+| --- | --- | --- |
+| `-c, --config <path>` | - | Path to a `config.json`. Defaults to `./config.json`. |
+| `--from <dir>` | - | Re-format previously-saved `completeGameProperties_*.json` files in `<dir>` instead of fetching (needs an earlier run with `keepCompleteProperties`). |
+| `-o, --out <dir>` | `outputDirectory` | Directory to write output files to. Default `output`. |
+| `--markets <codes>` | `markets` | Comma-separated market codes to fetch, e.g. `US,DE`. Enables flag-driven mode. |
+| `--platforms <list>` | `platformsToFetch` | Comma-separated platforms: `console,pc,eaPlay`. |
+| `--language <code>` | `language` | Language/locale for game properties, e.g. `en-us`. |
+| `--format <format>` | `outputFormat` | Output format: `array`, `productTitle`, `productId` or `0-indexed`. |
+| `--properties <list>` | `includedProperties` | Comma-separated properties to include: `productTitle,productId,developerName,publisherName,categories,storePage`. |
+| `--keep-complete` | `keepCompleteProperties` | Also keep the complete, unfiltered API response per platform and market. |
+| `--no-treat-empty-as-null` | `treatEmptyStringsAsNull` | Keep empty strings instead of converting them to `null`. |
+| `--save-config [path]` | - | Also write the assembled configuration to a file for reuse. Default `config.json`. |
+
+Nested options (image types, pricing, user ratings, descriptions, release dates) are only available through a `config.json` or the wizard.
+The `init` command takes `-o, --output <path>` to choose where the wizard writes the configuration file (default `config.json`).
+
 > Configuration files are validated against a JSON schema (`config.schema.json`, shipped with the package).
 > Add `"$schema": "config.schema.json"` to your `config.json`, with a copy of the schema next to it, and your editor will flag mistakes as you type.
 

bin/cli.js

@@ -5,7 +5,7 @@ import path from 'path';
 import { fileURLToPath } from 'url';
 import { Command } from 'commander';
 
-import { loadConfig, validateConfig } from '../js/utils.js';
+import { loadConfig, validateConfig, saveConfigToFile } from '../js/utils.js';
 import { run } from '../js/gamePass.js';
 import { runWizard } from '../js/wizard.js';
 import { buildConfig, usedBuildingFlags } from '../js/cliConfig.js';
@@ -33,12 +33,16 @@ program
 	.option('--properties <list>', 'comma-separated properties to include: productTitle,productId,developerName,publisherName,categories,storePage (flag-driven mode)')
 	.option('--keep-complete', 'also keep the complete, unfiltered API response per platform and market (flag-driven mode)')
 	.option('--no-treat-empty-as-null', 'keep empty strings instead of converting them to null (flag-driven mode)')
+	.option('--save-config [path]', 'also write the assembled configuration to a file for reuse (default: config.json; flag-driven mode)')
 	.addHelpText('after', '\nProvide a config.json (in the current directory or via --config), or build one from flags with --markets/--platforms/--properties etc. (unspecified options use their defaults).\nRun "game-pass-api init" to create a config interactively, or see the README and config.schema.json for every option.')
 	.action(async (options, command) => {
 		// Build the config entirely from flags when config-building flags are used (and no explicit --config file)
 		if (!options.config && usedBuildingFlags(command)) {
 			const config = buildConfig(options);
 			validateConfig(config);
+			if (options.saveConfig) {
+				await saveConfigToFile(config, options.saveConfig === true ? 'config.json' : options.saveConfig);
+			}
 			await run(config, { fromDirectory: options.from });
 			return;
 		}

js/utils.js

@@ -2,12 +2,36 @@ import jsonschema from 'jsonschema';
 import fs from 'fs';
 import path from 'path';
 import { fileURLToPath } from 'url';
+import { confirm } from '@inquirer/prompts';
 
 // The package root, so the shipped config schema is found no matter the working directory
 const packageDir = path.dirname(path.dirname(fileURLToPath(import.meta.url)));
 
 export let CONFIG;
 
+// ----- Saving a config -----
+
+// Write a flag-built config to disk for reuse, stripping any secret fields so they are never persisted
+// Prompts before overwriting an existing file in an interactive shell; refuses to overwrite non-interactively
+export async function saveConfigToFile(config, outputPath, secretFields = []) {
+	const toWrite = { ...config };
+	for (const field of secretFields) {
+		delete toWrite[field];
+	}
+	if (fs.existsSync(outputPath)) {
+		if (!process.stdin.isTTY) {
+			throw new Error(`"${outputPath}" already exists - remove it, or pass --save-config <path> with a different path.`);
+		}
+		const overwrite = await confirm({ message: `"${outputPath}" already exists. Overwrite it?`, default: false });
+		if (!overwrite) {
+			console.log('The existing configuration file was not changed.');
+			return;
+		}
+	}
+	fs.writeFileSync(outputPath, JSON.stringify(toWrite, null, 2));
+	console.log(`Wrote configuration to "${outputPath}".`);
+}
+
 // ----- Config -----
 
 // Load a config from the given path, or discover ./config.json in the current directory, then validate it against the shipped schema