asia-weex-vue-render4light/src/modules/storage.js

Web renderer for weex project written in Vue DSL.

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
/* global localStorage */

'use strict'

let supportLocalStorage = false
try {
    supportLocalStorage = typeof localStorage !== 'undefined'
}
catch (err) {
    // not support.
}

const SUCCESS = 'success'
const FAILED = 'failed'
const INVALID_PARAM = 'invalid_param'
const UNDEFINED = 'undefined'

function callFail (sender, callbackId, errorMsg) {
    sender.performCallback(callbackId, {
        result: FAILED,
        data: errorMsg || UNDEFINED
    })
}

function callNotSupportFail (sender, callbackId) {
    sender.performCallback(callbackId, {
        result: FAILED,
        data: 'localStorage is disabled or not supported.'
    })
}

const storage = {

    /**
     * When passed a key name and value, will add that key to the storage,
     * or update that key's value if it already exists.
     * @param {string} key
     * @param {string} value not null nor undifined，but 0 works.
     * @param {function} callbackId
     */
    setItem: function (key, value, callbackId) {
        const sender = this.sender
        if (!supportLocalStorage) {
            return callNotSupportFail(sender, callbackId)
        }
        if (!key || (!value && value !== 0)) {
            sender.performCallback(callbackId, {
                result: 'failed',
                data: INVALID_PARAM
            })
            return
        }
        try {
            localStorage.setItem(key, value)
        }
        catch (e) {
            // accept any exception thrown during a storage attempt as a quota error
            callFail(sender, callbackId)
        }
        sender.performCallback(callbackId, {
            result: SUCCESS,
            data: UNDEFINED
        })
    },

    /**
     * When passed a key name, will return that key's value.
     * @param {string} key
     * @param {function} callbackId
     */
    getItem: function (key, callbackId) {
        const sender = this.sender
        if (!supportLocalStorage) {
            return callNotSupportFail(sender, callbackId)
        }
        if (!key) {
            sender.performCallback(callbackId, {
                result: FAILED,
                data: INVALID_PARAM
            })
            return
        }
        let val
        try {
            val = localStorage.getItem(key)
        }
        catch (e) {
            // accept any exception thrown during a storage attempt as a quota error
            callFail(sender, callbackId)
        }
        sender.performCallback(callbackId, {
            result: val ? SUCCESS : FAILED,
            data: val || UNDEFINED
        })
    },

    /**
     *When passed a key name, will remove that key from the storage.
     * @param {string} key
     * @param {function} callbackId
     */
    removeItem: function (key, callbackId) {
        const sender = this.sender
        if (!supportLocalStorage) {
            return callNotSupportFail(sender, callbackId)
        }
        if (!key) {
            sender.performCallback(callbackId, {
                result: FAILED,
                data: INVALID_PARAM
            })
            return
        }
        try {
            localStorage.removeItem(key)
            sender.performCallback(callbackId, {
                result: SUCCESS,
                data: UNDEFINED
            })
        }
        catch (e) {
            // accept any exception thrown during a storage attempt as a quota error
            callFail(sender, callbackId)
        }
    },

    /**
     * Returns an integer representing the number of data items stored in the Storage object.
     * @param {function} callbackId
     */
    length: function (callbackId) {
        const sender = this.sender
        if (!supportLocalStorage) {
            return callNotSupportFail(sender, callbackId)
        }
        try {
            const len = localStorage.length
            sender.performCallback(callbackId, {
                result: SUCCESS,
                data: len
            })
        }
        catch (e) {
            // accept any exception thrown during a storage attempt as a quota error
            callFail(sender, callbackId)
        }
    },

    /**
     * Returns an array that contains all keys stored in Storage object.
     * @param {function} callbackId
     */
    getAllKeys: function (callbackId) {
        const sender = this.sender
        if (!supportLocalStorage) {
            return callNotSupportFail(sender, callbackId)
        }
        try {
            const _arr = []
            for (let i = 0; i < localStorage.length; i++) {
                _arr.push(localStorage.key(i))
            }
            sender.performCallback(callbackId, {
                result: SUCCESS,
                data: _arr
            })
        }
        catch (e) {
            // accept any exception thrown during a storage attempt as a quota error
            callFail(sender, callbackId)
        }
    }
}

const meta = {
    storage: [{
        name: 'setItem',
        args: ['string', 'string', 'function']
    }, {
        name: 'getItem',
        args: ['string', 'function']
    }, {
        name: 'removeItem',
        args: ['string', 'function']
    }, {
        name: 'length',
        args: ['function']
    }, {
        name: 'getAllKeys',
        args: ['function']
    }]
}

export default {
    init: function (Weex) {
        Weex.registerApiModule('storage', storage, meta)
    }
};