feat: add new command & export;

- creates a new migration file
- injects timestamp or sequential (inferred) prefix
- Closes #2

Author: lukeed

bin.js

@@ -33,4 +33,14 @@ sade('ley')
 		.option('-a, --all', 'Run all "down" migrations')
 		.action(wrap('down'))
 
+	.command('new <filename>')
+		.describe('Create a new migration file.')
+		.option('-t, --timestamp', 'Prefix the filename with a timestamp')
+		.option('-l, --length', 'The length of prefix, if not timestamp', 5)
+		.action((filename, opts) => {
+			opts.filename = filename;
+			return wrap('new')(opts);
+		})
+
+
 	.parse(process.argv);

index.js

@@ -1,4 +1,6 @@
 const { join, resolve } = require('path');
+const { writeFileSync } = require('fs');
+const mkdirs = require('mk-dirs');
 const $ = require('./lib/util');
 
 async function parse(opts) {
@@ -68,3 +70,33 @@ exports.down = async function (opts={}) {
 		if (client) await driver.end(client);
 	}
 }
+
+exports.new = async function (opts={}) {
+	let { migrations } = await parse(opts);
+
+	let prefix = '';
+	if (opts.timestamp) {
+		prefix += Date.now() / 1e3 | 0;
+	} else {
+		let tmp = migrations.pop();
+		if (tmp && /^\d+/.test(tmp.name)) {
+			tmp = parseInt(tmp.name.match(/^\d+/)[0], 10);
+			prefix = String(tmp + 1).padStart(opts.length, '0');
+		} else {
+			prefix = '0'.repeat(opts.length);
+		}
+	}
+
+	let filename = prefix + '-' + opts.filename.replace(/\s+/g, '-');
+	if (!/\.\w+$/.test(filename)) filename += '.js';
+	let dir = resolve(opts.cwd || '.', opts.dir);
+	let file = join(dir, filename);
+
+	await mkdirs(dir).then(() => {
+		let str = 'exports.up = async client => {\n\t// <insert magic here>\n};\n\n';
+		str += 'exports.down = async client => {\n\t// just in case...\n};\n';
+		writeFileSync(file, str);
+	});
+
+	return filename;
+}

ley.d.ts

@@ -17,11 +17,20 @@ declare namespace Options {
 	declare interface Down extends Base {
 		all?: boolean;
 	}
+
+	declare interface New extends Base {
+		filename: string;
+		timestamp?: boolean;
+		length?: number;
+	}
 }
 
 declare class MigrationError extends Error {
 	readonly migration: Record<'name'|'abs', string>;
 }
 
-export function up(opts?: Options.Up): Promise<void>;
-export function down(opts?: Options.Down): Promise<void>;
+export function up(opts?: Options.Up): Promise<string[]>;
+export function down(opts?: Options.Down): Promise<string[]>;
+
+declare function n(opts?: Options.New): Promise<string>;
+export { n as new };

lib/log.js

@@ -8,7 +8,10 @@ exports.info = msg => {
 exports.done = (type, arr) => {
 	let msg = '';
 
-	if (arr.length > 0) {
+	if (type === 'new') {
+		msg += 'Created ' + green('1') + ' file:';
+		msg += green().dim('\n    ⌁ ') + underline().grey(arr);
+	} else if (arr.length > 0) {
 		let i=0, arrow = type === 'up' ? '↑' : '↓';
 		msg += ('Migrated ' + green(arr.length) + (arr.length > 1 ? ' files:' : ' file:'));
 		for (; i < arr.length; i++) msg += (green().dim(`\n    ${arrow} `) + underline().grey(arr[i]));

package.json

@@ -26,6 +26,7 @@
   },
   "dependencies": {
     "kleur": "^3.0.3",
+    "mk-dirs": "^2.0.0",
     "sade": "^1.7.0",
     "totalist": "^1.0.1"
   },

readme.md

@@ -77,21 +77,19 @@ Because of this, it's often recommended to prefix migrations with a timestamp or
   |-- 002-seats.js
 ```
 
+> **Note**: You may create the next file via `ley new todos --length 3` where `todos` is a meaningful name for your project.<br>The above command will create the `migrations/003-todos.js` filepath — or similar, depending on your command arguments.
+
 ***Timestamped***
 
 ```
 /migrations
-  |-- 1581323445664-users.js
-  |-- 1581323453868-teams.js
-  |-- 1581323458383-seats.js
+  |-- 1581323445-users.js
+  |-- 1581323453-teams.js
+  |-- 1581323458-seats.js
 ```
 
-**Tip:** Create timestamped migration files on the command line using `touch` and `date`:
+> **Note**: You may create the next file via `ley new todos --timestamp` where `todos` is a meaningful name for your project.<br>The above command will create the `migrations/1584389617-todos.js` filepath — or similar, depending on your command arguments.
 
-```
-$ touch "$(date +%s)-users.js"
-#=> 1581785004-users.js
-```
 
 **The order of your migrations is critically important!**<br>Migrations must be treated as an append-only immutable task chain. Without this, there's no way to _reliably_ rollback or recreate your database.
 
@@ -239,6 +237,47 @@ Enable to apply **all** migration files' `down` task.<br>
 By default, only the most recently-applied migration file is invoked.
 
 
+### ley.new(opts?)
+Returns: `Promise<string>`
+
+Returns the newly created _relative filename_ (eg, `000-users.js`).
+
+#### opts.filename
+Type: `string`
+
+**Required.** The name of the file to be created.
+
+> **Note:** A prefix will be prepended based on [`opts.timestamp`](#optstimestamp) and [`opts.length`](#optslength) values.<br>The `.js` extension will be applied unless your input already has an extension.
+
+#### opts.timestamp
+Type: `boolean`<br>
+Default: `false`
+
+Should the migration file have a timestamped prefix?<br>
+If so, will use `Date.now()` floored to the nearest second.
+
+#### opts.length
+Type: `number`<br>
+Default: `5`
+
+When **not** using a timestamped prefix, this value controls the prefix total length.<br>
+For example, `00000-users.js` will be followed by `00001-teams.js`.
+
+#### opts.cwd
+Type: `string`<br>
+Default: `.`
+
+A target location to treat as the current working directory.
+
+> **Note:** This value is `path.resolve()`d from the current `process.cwd()` location.
+
+#### opts.dir
+Type: `string`<br>
+Default: `migrations`
+
+The directory (relative to `opts.cwd`) to find migration files.
+
+
 ## License
 
 MIT © [Luke Edwards](https://lukeed.com)