sqlite3 and pg now is optional dependencies

.travis.yml

@@ -2,6 +2,7 @@ language: node_js
 node_js:
   - "0.10"
   - "0.12"
+  - "4"
 addons:
   firefox: "38.0"
   postgresql: "9.3"

package.json

@@ -1,6 +1,6 @@
 {
   "name": "odd-storage",
-  "version": "0.4.5",
+  "version": "0.4.6",
   "description": "node.js and browser storage",
   "keywords": [
     "storage",
@@ -47,9 +47,7 @@
     "core-decorators": "^0.8.1",
     "error-system": "^1.0.0",
     "make-concurrent": "^1.1.1",
-    "pg": "^4.4.3",
-    "ready-mixin": "^2.0.0",
-    "sqlite3": "^3.0.8"
+    "ready-mixin": "^2.0.0"
   },
   "devDependencies": {
     "babel": "^5.8.21",
@@ -68,7 +66,9 @@
     "karma-detect-browsers": "^2.0.2",
     "karma-firefox-launcher": "^0.1.6",
     "karma-mocha": "^0.2.0",
-    "mocha": "^2.2.5"
+    "mocha": "^2.2.5",
+    "pg": "^4.4.3",
+    "sqlite3": "^3.0.8"
   },
   "browser": {
     "./lib/index.js": "./lib/index-browser.js",

src/sql/postgresql.js

@@ -1,5 +1,3 @@
-import pg from 'pg'
-
 import AbstractSQLStorage from './abstract'
 
 /**
@@ -16,13 +14,20 @@ export default class PostgreSQLStorage extends AbstractSQLStorage {
     super()
 
     this._url = Object(opts).url
-    this._pg = Object(opts).native === true ? pg.native : pg
+    this._useNative = !!Object(opts).native
   }
 
   /**
    * @return {boolean}
    */
-  static isAvailable () { return true }
+  static isAvailable () {
+    try {
+      require('pg')
+      return true
+    } catch (err) {
+      return false
+    }
+  }
 
   /**
    * @param {string} sql
@@ -65,7 +70,12 @@ export default class PostgreSQLStorage extends AbstractSQLStorage {
    * @return {Promise}
    */
   open () {
-    return this._query('SELECT * FROM information_schema.tables')
+    return Promise.resolve()
+      .then(() => {
+        let pg = require('pg')
+        this._pg = this._useNative ? pg.native : pg
+        return this._query('SELECT * FROM information_schema.tables')
+      })
       .then(() => { this._ready(null) }, (err) => {
         this._ready(err)
         throw err

src/sql/sqlite.js

@@ -1,5 +1,3 @@
-import sqlite3 from 'sqlite3'
-
 import AbstractSQLStorage from './abstract'
 
 /**
@@ -19,13 +17,21 @@ export default class SQLiteStorage extends AbstractSQLStorage {
   /**
    * @return {boolean}
    */
-  static isAvailable () { return true }
+  static isAvailable () {
+    try {
+      require('sqlite3')
+      return true
+    } catch (err) {
+      return false
+    }
+  }
 
   /**
    * @return {Promise}
    */
   open () {
     return new Promise((resolve, reject) => {
+      let sqlite3 = require('sqlite3')
       this._db = new sqlite3.Database(this._filename, (err) => {
         if (err !== null) {
           return reject(err)

src/sql/websql.js

@@ -1,5 +1,4 @@
 import AbstractSQLStorage from './abstract'
-import { isFunction } from '../util'
 
 /**
  * @class WebSQLStorage
@@ -24,7 +23,7 @@ export default class WebSQLStorage extends AbstractSQLStorage {
   /**
    * @return {boolean}
    */
-  static isAvailable () { return isFunction(global.openDatabase) }
+  static isAvailable () { return global.openDatabase === 'function' }
 
   /**
    * @return {Promise}

src/sync/indexeddb.js

@@ -1,5 +1,4 @@
 import AbstractSyncStorage from './abstract'
-import { isFunction } from '../util'
 
 // https://developer.mozilla.org/en-US/docs/Web/API/IDBFactory/open
 var indexedDB = (global.indexedDB ||
@@ -25,7 +24,7 @@ export default class IndexedDBStorag extends AbstractSyncStorage {
    * @return {boolean}
    */
   static isAvailable () {
-    return (typeof indexedDB === 'object' && isFunction(indexedDB.open))
+    return (typeof indexedDB === 'object' && typeof indexedDB.open === 'function')
   }
 
   /**

src/sync/localstorage.js

@@ -1,5 +1,4 @@
 import AbstractSyncStorage from './abstract'
-import { isFunction } from '../util'
 
 /**
  * @class LocalStorage
@@ -20,9 +19,9 @@ export default class LocalStorage extends AbstractSyncStorage {
    */
   static isAvailable () {
     return (typeof global.localStorage === 'object' &&
-            isFunction(global.localStorage.getItem) &&
-            isFunction(global.localStorage.setItem) &&
-            isFunction(global.localStorage.clear))
+            typeof global.localStorage.getItem === 'function' &&
+            typeof global.localStorage.setItem === 'function' &&
+            typeof global.localStorage.clear === 'function')
   }
 
   /**