CAPH.DAL.LOCALSTORAGECACHE
LocalStorageCache is a class that provides caching functions. It uses HTML5 Local Storage. Main APIs of LocalStorageCache are 'find', 'insertBlob', 'insertBinary', 'insertText', 'get' and 'remove.' Using find method, a user can find an item with a key, which is usually a URL. Using insertBlob method, a user can insert a Blob into the cache. Using insertBinary method, a user can insert binary into the cache. Using insertText method, a user can insert text into the cache. Using get method, a user can get cached data. Using remove method, a user can remove a cache entry.
Contents
Constructor
LocalStorageCache | ||
Description | ||
Construct a LocalStorageCache | ||
Emulator Support | Y | |
SDK Constraint | None | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); |
Methods
encodeUInt8ArrayToBase64 | ||
Description | ||
Encode a Uint8 TypedArray to a base64 string | ||
Parameters | ■input - Uint8 TypedArray - A Uint8 TypedArray as an input. - [default : null] | |
Return | ■String - A base64-encoded string | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var BaseCache = caph.dal.BaseCache; var basecache = new BaseCache(); // Let's say data - - binary is given var uInt8Array = new Uint8Array(binary); var binaryData = basecache.encodeUInt8ArrayToBase64(uInt8Array); |
queryMetadata | ||
Description | ||
Query metadata | ||
Parameters | ■url - String - url The key, URL - default : null | |
Return | ■Object - Metadata for the given URL. | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCach var url = 'http://www.foo.com'; var metadata = queryMetadata(url); |
LocalStorageCache | ||
Description | ||
(Constructor) Construct a LocalStorageCache | ||
Parameters | ■Void | |
Return | ■LocalStorageCache - Instance of LocalStorageCache | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); |
remove | ||
Description | ||
Remove an item | ||
Parameters | ■url - String - the key. URL | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); // Let's say parameter - url is given var removeFileName = localstoragecache.find(url); localstoragecache.remove(removeFileName, function(){}, function (){} ); |
setBase64Proxy | ||
Description | ||
Set the Base64Encoder Proxy | ||
Parameters | ■proxy - Object - default value : null - A Base64Encoder Proxy | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); // Let's say the proxy is already given. localstoragecache.setBase64Proxy(proxy); |
insertBinary | ||
Description | ||
Insert item into localstorage as binary type | ||
Parameters | ■options - Object * url : the key * URL; blob : blob * size : the size of the encoded blob ■onSuccessCallback (Optional) - Function - callback on success. ■onFailureCallback (Optional) - Function - callback on failure. | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); function onSuccessCallback() { console.log("insertBinary success"); } function onFailureCallback() { console.log("insertBinary failure"); } // Let's say data - - url, binaryData, and size are given var options = {}; options.url = url; options.binary = binaryData; options.size = size; localstoragecache.insertBinary(options, onSuccessCallback, onFailureCallback); |
insertBlob | ||
Description | ||
Insert item into localstorage as blob type | ||
Parameters | ■options - Object * url : the key * URL; blob : blob * size : the size of the encoded blob ■onSuccessCallback (Optional) - Function - callback on success. ■onFailureCallback (Optional) - Function - callback on failure. | |
Return | ■Boolean - false, if fails; undefined, otherwise | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); function onSuccessCallback() { console.log("insertBlob success"); } function onFailureCallback() { console.log("insertBlob failure"); } // Let's say data - - url, blobData, and size are given var options = {}; options.url = url; options.blob = blobData; options.size = size; localstoragecache.insertBlob(options, onSuccessCallback, onFailureCallback); |
insertText | ||
Description | ||
Insert item into localstorage as text type | ||
Parameters | ■options - Object * url : the key * URL; blob : blob * size : the size of the encoded blob ■onSuccessCallback (Optional) - Function - callback on success. ■onFailureCallback (Optional) - Function - callback on failure. | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); function onSuccessCallback() { console.log("insertText success"); } function onFailureCallback() { console.log("insertText failure"); } // Let's say data - - url, text, and size are given var options = {}; options.url = url; options.text = text; options.size = size; localstoragecache.insertText(options, onSuccessCallback, onFailureCallback); |
find | ||
Description | ||
Find an item | ||
Parameters | ■url - String - the key. URL | |
Return | ■Boolean - true, if it is found; false, otherwise | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); function successCallback () { console.log("insertBlob success"); } function failureCallback() { console.log("insertBlob failure"); } // Let's say data - - url, blobData, and size are given var option = {}; options.url = url; options.blob = blobData; options.size = size; localstoragecache.insertBlob(options, successCallback failureCallback); var fileURL = option.url; var result = localstorage.find(fileURL); //return true |
clearAll | ||
Description | ||
Clear all key/value pairs in the LocalStorageCache | ||
Parameters | ■Void | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); localstoragecache.clearAll(); |
init | ||
Description | ||
Initialize LocalStorageCache for caching | ||
Parameters | ■prefix - String - prefix must be given. ■sizeLimitInBytes - Number - Size limit in bytes, localstoragecache's limit. ■successCallback (Optional) - function - this callback will be executed after initialize loaclstorage ■failureCallback (Optional) - function - Callback on failure | |
Return | ■Boolean - false, if fails; undefined, otherwise | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); localstoragecache.init("localstoragecache", 1024*1024*5/2, function() { console.log("success initializing localstoragecache"); }); |
storeMeta | ||
Description | ||
Store metadata to a LocalStorage | ||
Parameters | ■Void | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); localstoragecache.storeMeta(); |
doLRU | ||
Description | ||
Remove some entries by using LRU algorithm | ||
Parameters | ■size - Number - A target size - [default : null] | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); localstoragecahe.doLRU(2 * 1024 * 1024); |
getItemCount | ||
Description | ||
Returns item count | ||
Parameters | ■Void | |
Return | ■Number - Number of Items | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var count = localstoragecache.getItemCount(); |
get | ||
Description | ||
Get the item. It is searched by given parameter, url | ||
Parameters | ■url - String - the key. URL | |
Return | ■Object - Object to return | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var item = localstoragecache.get(fileName); var img = document.createElement('img'); img.src = item; document.body.appendChild(img); |
buildItemKey | ||
Description | ||
Make a key for an item | ||
Parameters | ■key - String - A unique key of an item - [default : null] | |
Return | ■String - A key for an item | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var keyString = localstoragecache.buildItemKey('http://www.foo.com'); |
buildMetaKey | ||
Description | ||
Build a key for the metadata record | ||
Parameters | ■Void | |
Return | ■String - A key string for the metadata record | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var keyString = localstoragecache.buildMetaKey(); |
buildJSONFromMeta | ||
Description | ||
Build a JSON string From Metadata | ||
Parameters | ■meta - Object - A metadata - [default : null] | |
Return | ■String - A JSON string represents a metadata item | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var meta = {}; meta._metaArray = []; meta._metaArray.push('foo'); var jsonString = localstoragecache.buildJSONFromMeta(meta); |
buildMetaFromJSON | ||
Description | ||
Build Metadata From a JSON string | ||
Parameters | ■meta - Object - A metadata - [default : null] ■json - String - A JSON for metadata - [default : null] | |
Return | ■Void | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var meta = {}; meta._metaArray = []; var json = ['foo']; localstoragecache.buildMetaFromJSON(meta, json); |
getTotalSize | ||
Description | ||
Get the total item byte size | ||
Parameters | ■Void | |
Return | ■Number - Total Item Byte Size of the LocalStorageCache | |
Emulator Support | Y | |
SDK Constraint | none | |
Example | ||
var LocalStorageCache = caph.dal.LocalStorageCache; var localstoragecache = new LocalStorageCache(); var totalSize = localstoragecache.getTotalSize(); |