Create location directory recursively (#6)

README.md

@@ -173,7 +173,7 @@ An `abstract-level` and thus `classic-level` database is at its core a [key-valu
 
 ### `db = new ClassicLevel(location[, options])`
 
-Create a database or open an existing database. The `location` argument must be a directory path (relative or absolute) where LevelDB will store its files. The optional `options` object may contain:
+Create a database or open an existing database. The `location` argument must be a directory path (relative or absolute) where LevelDB will store its files. If the directory does not yet exist (and `options.createIfMissing` is true) it will be created recursively. The optional `options` object may contain:
 
 - `keyEncoding` (string or object, default `'utf8'`): encoding to use for keys
 - `valueEncoding` (string or object, default `'utf8'`): encoding to use for values.

index.js

@@ -3,6 +3,7 @@
 const { AbstractLevel } = require('abstract-level')
 const ModuleError = require('module-error')
 const { fromCallback } = require('catering')
+const fs = require('fs')
 const binding = require('./binding')
 const { ChainedBatch } = require('./chained-batch')
 const { Iterator } = require('./iterator')
@@ -47,7 +48,14 @@ class ClassicLevel extends AbstractLevel {
   }
 
   _open (options, callback) {
-    binding.db_open(this[kContext], this[kLocation], options, callback)
+    if (options.createIfMissing) {
+      fs.mkdir(this[kLocation], { recursive: true }, (err) => {
+        if (err) return callback(err)
+        binding.db_open(this[kContext], this[kLocation], options, callback)
+      })
+    } else {
+      binding.db_open(this[kContext], this[kLocation], options, callback)
+    }
   }
 
   _close (callback) {

test/mkdir-test.js

@@ -0,0 +1,35 @@
+'use strict'
+
+const test = require('tape')
+const tempy = require('tempy')
+const path = require('path')
+const fs = require('fs')
+const { ClassicLevel } = require('..')
+
+test('creates location directory recursively', async function (t) {
+  const location = path.join(tempy.directory(), 'beep', 'boop')
+  const db = new ClassicLevel(location)
+
+  t.is(fs.existsSync(location), false)
+  await db.open()
+  t.is(fs.existsSync(location), true)
+})
+
+test('does not create location directory recursively if createIfMissing is false', async function (t) {
+  t.plan(3)
+
+  const location = path.join(tempy.directory(), 'beep', 'boop')
+  const db = new ClassicLevel(location, { createIfMissing: false })
+
+  try {
+    await db.open()
+  } catch (err) {
+    t.is(err.code, 'LEVEL_DATABASE_NOT_OPEN')
+
+    // Error message is inconsistent between platforms so not checked
+    t.ok(err.cause)
+
+    // On Windows, LevelDB itself creates the directory (technically a bug)
+    t.is(fs.existsSync(location), process.platform === 'win32')
+  }
+})