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- Architectural overview of Cordova platform
- 创建你的第一个App
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- CLI Reference
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- Battery Status
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File
This plugin implements a File API allowing read/write access to files residing on the device.
This plugin is based on several specs, including : The HTML5 File API http://www.w3.org/TR/FileAPI/
The (now-defunct) Directories and System extensions Latest: http://www.w3.org/TR/2012/WD-file-system-api-20120417/ Although most of the plugin code was written when an earlier spec was current: http://www.w3.org/TR/2011/WD-file-system-api-20110419/
It also implements the FileWriter spec : http://dev.w3.org/2009/dap/file-system/file-writer.html
For usage, please refer to HTML5 Rocks' excellent FileSystem article.
For an overview of other storage options, refer to Cordova's storage guide.
This plugin defines global cordova.file
object.
Although in the global scope, it is not available until after the deviceready
event.
document.addEventListener("deviceready", onDeviceReady, false);
function onDeviceReady() {
console.log(cordova.file);
}
Report issues on the Apache Cordova issue tracker
Installation
cordova plugin add cordova-plugin-file
Supported Platforms
- Amazon Fire OS
- Android
- BlackBerry 10
- Firefox OS
- iOS
- OS X
- Windows Phone 7 and 8*
- Windows 8*
- Windows*
- Browser
* These platforms do not support FileReader.readAsArrayBuffer
nor FileWriter.write(blob)
.
Where to Store Files
As of v1.2.0, URLs to important file-system directories are provided. Each URL is in the form file:///path/to/spot/, and can be converted to a DirectoryEntry
using window.resolveLocalFileSystemURL()
.
cordova.file.applicationDirectory
- Read-only directory where the application is installed. (iOS, Android, BlackBerry 10, OSX, windows)cordova.file.applicationStorageDirectory
- Root directory of the application's sandbox; on iOS & windows this location is read-only (but specific subdirectories [like/Documents
on iOS or/localState
on windows] are read-write). All data contained within is private to the app. (iOS, Android, BlackBerry 10, OSX)cordova.file.dataDirectory
- Persistent and private data storage within the application's sandbox using internal memory (on Android, if you need to use external memory, use.externalDataDirectory
). On iOS, this directory is not synced with iCloud (use.syncedDataDirectory
). (iOS, Android, BlackBerry 10, windows)cordova.file.cacheDirectory
- Directory for cached data files or any files that your app can re-create easily. The OS may delete these files when the device runs low on storage, nevertheless, apps should not rely on the OS to delete files in here. (iOS, Android, BlackBerry 10, OSX, windows)cordova.file.externalApplicationStorageDirectory
- Application space on external storage. (Android)cordova.file.externalDataDirectory
- Where to put app-specific data files on external storage. (Android)cordova.file.externalCacheDirectory
- Application cache on external storage. (Android)cordova.file.externalRootDirectory
- External storage (SD card) root. (Android, BlackBerry 10)cordova.file.tempDirectory
- Temp directory that the OS can clear at will. Do not rely on the OS to clear this directory; your app should always remove files as applicable. (iOS, OSX, windows)cordova.file.syncedDataDirectory
- Holds app-specific files that should be synced (e.g. to iCloud). (iOS, windows)cordova.file.documentsDirectory
- Files private to the app, but that are meaningful to other application (e.g. Office files). Note that for OSX this is the user's~/Documents
directory. (iOS, OSX)cordova.file.sharedDirectory
- Files globally available to all applications (BlackBerry 10)
File System Layouts
Although technically an implementation detail, it can be very useful to know how the cordova.file.*
properties map to physical paths on a real device.
iOS File System Layout
Device Path | cordova.file.* | iosExtraFileSystems | r/w? | persistent? | OS clears | sync | private |
---|---|---|---|---|---|---|---|
/var/mobile/Applications/<UUID>/ | applicationStorageDirectory | - | r | N/A | N/A | N/A | Yes |
appname.app/ | applicationDirectory | bundle | r | N/A | N/A | N/A | Yes |
www/ | - | - | r | N/A | N/A | N/A | Yes |
Documents/ | documentsDirectory | documents | r/w | Yes | No | Yes | Yes |
NoCloud/ | - | documents-nosync | r/w | Yes | No | No | Yes |
Library | - | library | r/w | Yes | No | Yes? | Yes |
NoCloud/ | dataDirectory | library-nosync | r/w | Yes | No | No | Yes |
Cloud/ | syncedDataDirectory | - | r/w | Yes | No | Yes | Yes |
Caches/ | cacheDirectory | cache | r/w | Yes* | Yes*** | No | Yes |
tmp/ | tempDirectory | - | r/w | No** | Yes*** | No | Yes |
* Files persist across app restarts and upgrades, but this directory can be cleared whenever the OS desires. Your app should be able to recreate any content that might be deleted.
** Files may persist across app restarts, but do not rely on this behavior. Files are not guaranteed to persist across updates. Your app should remove files from this directory when it is applicable, as the OS does not guarantee when (or even if) these files are removed.
*** The OS may clear the contents of this directory whenever it feels it is necessary, but do not rely on this. You should clear this directory as appropriate for your application.
Android File System Layout
Device Path | cordova.file.* | AndroidExtraFileSystems | r/w? | persistent? | OS clears | private |
---|---|---|---|---|---|---|
file:///android_asset/ | applicationDirectory | r | N/A | N/A | Yes | |
/data/data/<app-id>/ | applicationStorageDirectory | - | r/w | N/A | N/A | Yes |
cache | cacheDirectory | cache | r/w | Yes | Yes* | Yes |
files | dataDirectory | files | r/w | Yes | No | Yes |
Documents | documents | r/w | Yes | No | Yes | |
<sdcard>/ | externalRootDirectory | sdcard | r/w | Yes | No | No |
Android/data/<app-id>/ | externalApplicationStorageDirectory | - | r/w | Yes | No | No |
cache | externalCacheDirectry | cache-external | r/w | Yes | No** | No |
files | externalDataDirectory | files-external | r/w | Yes | No | No |
* The OS may periodically clear this directory, but do not rely on this behavior. Clear the contents of this directory as appropriate for your application. Should a user purge the cache manually, the contents of this directory are removed.
** The OS does not clear this directory automatically; you are responsible for managing the contents yourself. Should the user purge the cache manually, the contents of the directory are removed.
Note: If external storage can't be mounted, the cordova.file.external*
properties are null
.
BlackBerry 10 File System Layout
Device Path | cordova.file.* | r/w? | persistent? | OS clears | private |
---|---|---|---|---|---|
file:///accounts/1000/appdata/<app id>/ | applicationStorageDirectory | r | N/A | N/A | Yes |
app/native | applicationDirectory | r | N/A | N/A | Yes |
data/webviews/webfs/temporary/local__0 | cacheDirectory | r/w | No | Yes | Yes |
data/webviews/webfs/persistent/local__0 | dataDirectory | r/w | Yes | No | Yes |
file:///accounts/1000/removable/sdcard | externalRemovableDirectory | r/w | Yes | No | No |
file:///accounts/1000/shared | sharedDirectory | r/w | Yes | No | No |
Note: When application is deployed to work perimeter, all paths are relative to /accounts/1000-enterprise.
OS X File System Layout
Device Path | cordova.file.* | iosExtraFileSystems | r/w? | OS clears | private |
---|---|---|---|---|---|
/Applications/<appname>.app/ | - | bundle | r | N/A | Yes |
Content/Resources/ | applicationDirectory | - | r | N/A | Yes |
~/Library/Application Support/<bundle-id>/ | applicationStorageDirectory | - | r/w | No | Yes |
files/ | dataDirectory | - | r/w | No | Yes |
~/Documents/ | documentsDirectory | documents | r/w | No | No |
~/Library/Caches/<bundle-id>/ | cacheDirectory | cache | r/w | No | Yes |
/tmp/ | tempDirectory | - | r/w | Yes* | Yes |
/ | rootDirectory | root | r/w | No** | No |
Note: This is the layout for non sandboxed applications. I you enable sandboxing, the applicationStorageDirectory
will be below ~/Library/Containers/<bundle-id>/Data/Library/Application Support
.
* Files persist across app restarts and upgrades, but this directory can be cleared whenever the OS desires. Your app should be able to recreate any content that might be deleted. You should clear this directory as appropriate for your application.
** Allows access to the entire file system. This is only available for non sandboxed apps.
Windows File System Layout
Device Path | cordova.file.* | r/w? | persistent? | OS clears | private |
---|---|---|---|---|---|
ms-appdata:/// | applicationDirectory | r | N/A | N/A | Yes |
local/ | dataDirectory | r/w | Yes | No | Yes |
temp/ | cacheDirectory | r/w | No | Yes* | Yes |
temp/ | tempDirectory | r/w | No | Yes* | Yes |
roaming/ | syncedDataDirectory | r/w | Yes | No | Yes |
* The OS may periodically clear this directory
Android Quirks
Android Persistent storage location
There are multiple valid locations to store persistent files on an Android device. See this page for an extensive discussion of the various possibilities.
Previous versions of the plugin would choose the location of the temporary and persistent files on startup, based on whether the device claimed that the SD Card (or equivalent storage partition) was mounted. If the SD Card was mounted, or if a large internal storage partition was available (such as on Nexus devices,) then the persistent files would be stored in the root of that space. This meant that all Cordova apps could see all of the files available on the card.
If the SD card was not available, then previous versions would store data under /data/data/<packageId>
, which isolates apps from each other, but may still cause data to be shared between users.
It is now possible to choose whether to store files in the internal file storage location, or using the previous logic, with a preference in your application's config.xml
file. To do this, add one of these two lines to config.xml
:
<preference name="AndroidPersistentFileLocation" value="Internal" />
<preference name="AndroidPersistentFileLocation" value="Compatibility" />
Without this line, the File plugin will use Internal
as the default. If a preference tag is present, and is not one of these values, the application will not start.
If your application has previously been shipped to users, using an older (pre- 3.0.0) version of this plugin, and has stored files in the persistent filesystem, then you should set the preference to Compatibility
if your config.xml does not specify a location for the persistent filesystem. Switching the location to "Internal" would mean that existing users who upgrade their application may be unable to access their previously-stored files, depending on their device.
If your application is new, or has never previously stored files in the persistent filesystem, then the Internal
setting is generally recommended.
Slow recursive operations for /android_asset
Listing asset directories is really slow on Android. You can speed it up though, by adding src/android/build-extras.gradle
to the root of your android project (also requires cordova-android@4.0.0 or greater).
iOS Quirks
cordova.file.applicationStorageDirectory
is read-only; attempting to store files within the root directory will fail. Use one of the othercordova.file.*
properties defined for iOS (onlyapplicationDirectory
andapplicationStorageDirectory
are read-only).FileReader.readAsText(blob, encoding)
- The
encoding
parameter is not supported, and UTF-8 encoding is always in effect.
- The
iOS Persistent storage location
There are two valid locations to store persistent files on an iOS device: the Documents directory and the Library directory. Previous versions of the plugin only ever stored persistent files in the Documents directory. This had the side-effect of making all of an application's files visible in iTunes, which was often unintended, especially for applications which handle lots of small files, rather than producing complete documents for export, which is the intended purpose of the directory.
It is now possible to choose whether to store files in the documents or library directory, with a preference in your application's config.xml
file. To do this, add one of these two lines to config.xml
:
<preference name="iosPersistentFileLocation" value="Library" />
<preference name="iosPersistentFileLocation" value="Compatibility" />
Without this line, the File plugin will use Compatibility
as the default. If a preference tag is present, and is not one of these values, the application will not start.
If your application has previously been shipped to users, using an older (pre- 1.0) version of this plugin, and has stored files in the persistent filesystem, then you should set the preference to Compatibility
. Switching the location to Library
would mean that existing users who upgrade their application would be unable to access their previously-stored files.
If your application is new, or has never previously stored files in the persistent filesystem, then the Library
setting is generally recommended.
Firefox OS Quirks
The File System API is not natively supported by Firefox OS and is implemented as a shim on top of indexedDB.
- Does not fail when removing non-empty directories
- Does not support metadata for directories
- Methods
copyTo
andmoveTo
do not support directories
The following data paths are supported:
applicationDirectory
- Usesxhr
to get local files that are packaged with the app.dataDirectory
- For persistent app-specific data files.cacheDirectory
- Cached files that should survive app restarts (Apps should not rely on the OS to delete files in here).
Browser Quirks
Common quirks and remarks
- Each browser uses its own sandboxed filesystem. IE and Firefox use IndexedDB as a base. All browsers use forward slash as directory separator in a path.
- Directory entries have to be created successively. For example, the call
fs.root.getDirectory('dir1/dir2', {create:true}, successCallback, errorCallback)
will fail if dir1 did not exist. - The plugin requests user permission to use persistent storage at the application first start.
- Plugin supports
cdvfile://localhost
(local resources) only. I.e. external resources are not supported viacdvfile
. - The plugin does not follow "File System API 8.3 Naming restrictions".
- Blob and File'
close
function is not supported. FileSaver
andBlobBuilder
are not supported by this plugin and don't have stubs.- The plugin does not support
requestAllFileSystems
. This function is also missing in the specifications. - Entries in directory will not be removed if you use
create: true
flag for existing directory. - Files created via constructor are not supported. You should use entry.file method instead.
- Each browser uses its own form for blob URL references.
readAsDataURL
function is supported, but the mediatype in Chrome depends on entry name extension, mediatype in IE is always empty (which is the same astext-plain
according the specification), the mediatype in Firefox is alwaysapplication/octet-stream
. For example, if the content isabcdefg
then Firefox returnsdata:application/octet-stream;base64,YWJjZGVmZw==
, IE returnsdata:;base64,YWJjZGVmZw==
, Chrome returnsdata:<mediatype depending on extension of entry name>;base64,YWJjZGVmZw==
.toInternalURL
returns the path in the formfile:///persistent/path/to/entry
(Firefox, IE). Chrome returns the path in the formcdvfile://localhost/persistent/file
.
Chrome quirks
- Chrome filesystem is not immediately ready after device ready event. As a workaround you can subscribe to
filePluginIsReady
event. Example:javascript window.addEventListener('filePluginIsReady', function(){ console.log('File plugin is ready');}, false);
You can usewindow.isFilePluginReadyRaised
function to check whether event was already raised. - window.requestFileSystem TEMPORARY and PERSISTENT filesystem quotas are not limited in Chrome.
- To increase persistent storage in Chrome you need to call
window.initPersistentFileSystem
method. Persistent storage quota is 5 MB by default. - Chrome requires
--allow-file-access-from-files
run argument to support API viafile:///
protocol. File
object will be not changed if you use flag{create:true}
when getting an existingEntry
.- events
cancelable
property is set to true in Chrome. This is contrary to the specification. toURL
function in Chrome returnsfilesystem:
-prefixed path depending on application host. For example,filesystem:file:///persistent/somefile.txt
,filesystem:http://localhost:8080/persistent/somefile.txt
.toURL
function result does not contain trailing slash in case of directory entry. Chrome resolves directories with slash-trailed urls correctly though.resolveLocalFileSystemURL
method requires the inboundurl
to havefilesystem
prefix. For example,url
parameter forresolveLocalFileSystemURL
should be in the formfilesystem:file:///persistent/somefile.txt
as opposed to the formfile:///persistent/somefile.txt
in Android.- Deprecated
toNativeURL
function is not supported and does not have a stub. setMetadata
function is not stated in the specifications and not supported.- INVALIDMODIFICATIONERR (code: 9) is thrown instead of SYNTAX_ERR(code: 8) on requesting of a non-existant filesystem.
- INVALIDMODIFICATIONERR (code: 9) is thrown instead of PATHEXISTSERR(code: 12) on trying to exclusively create a file or directory, which already exists.
- INVALIDMODIFICATIONERR (code: 9) is thrown instead of NOMODIFICATIONALLOWED_ERR(code: 6) on trying to call removeRecursively on the root file system.
- INVALIDMODIFICATIONERR (code: 9) is thrown instead of NOTFOUNDERR(code: 1) on trying to moveTo directory that does not exist.
IndexedDB-based impl quirks (Firefox and IE)
.
and..
are not supported.- IE does not support
file:///
-mode; only hosted mode is supported (http://localhost:xxxx). - Firefox filesystem size is not limited but each 50MB extension will request a user permission. IE10 allows up to 10mb of combined AppCache and IndexedDB used in implementation of filesystem without prompting, once you hit that level you will be asked if you want to allow it to be increased up to a max of 250mb per site. So
size
parameter forrequestFileSystem
function does not affect filesystem in Firefox and IE. readAsBinaryString
function is not stated in the Specs and not supported in IE and does not have a stub.file.type
is always null.- You should not create entry using DirectoryEntry instance callback result which was deleted. Otherwise, you will get a 'hanging entry'.
- Before you can read a file, which was just written you need to get a new instance of this file.
setMetadata
function, which is not stated in the Specs supportsmodificationTime
field change only.copyTo
andmoveTo
functions do not support directories.- Directories metadata is not supported.
- Both Entry.remove and directoryEntry.removeRecursively don't fail when removing non-empty directories - directories being removed are cleaned along with contents instead.
abort
andtruncate
functions are not supported.- progress events are not fired. For example, this handler will be not executed:
javascript writer.onprogress = function() { /*commands*/ };
Upgrading Notes
In v1.0.0 of this plugin, the FileEntry
and DirectoryEntry
structures have changed, to be more in line with the published specification.
Previous (pre-1.0.0) versions of the plugin stored the device-absolute-file-location in the fullPath
property of Entry
objects. These paths would typically look like
/var/mobile/Applications/<application UUID>/Documents/path/to/file (iOS)
/storage/emulated/0/path/to/file (Android)
These paths were also returned by the toURL()
method of the Entry
objects.
With v1.0.0, the fullPath
attribute is the path to the file, relative to the root of the HTML filesystem. So, the above paths would now both be represented by a FileEntry
object with a fullPath
of
/path/to/file
If your application works with device-absolute-paths, and you previously retrieved those paths through the fullPath
property of Entry
objects, then you should update your code to use entry.toURL()
instead.
For backwards compatibility, the resolveLocalFileSystemURL()
method will accept a device-absolute-path, and will return an Entry
object corresponding to it, as long as that file exists within either the TEMPORARY
or PERSISTENT
filesystems.
This has particularly been an issue with the File-Transfer plugin, which previously used device-absolute-paths (and can still accept them). It has been updated to work correctly with FileSystem URLs, so replacing entry.fullPath
with entry.toURL()
should resolve any issues getting that plugin to work with files on the device.
In v1.1.0 the return value of toURL()
was changed (see CB-6394) to return an absolute 'file://' URL. wherever possible. To ensure a 'cdvfile:'-URL you can use toInternalURL()
now. This method will now return filesystem URLs of the form
cdvfile://localhost/persistent/path/to/file
which can be used to identify the file uniquely.
cdvfile protocol
Purpose
cdvfile://localhost/persistent|temporary|another-fs-root*/path/to/file
can be used for platform-independent file paths. cdvfile paths are supported by core plugins - for example you can download an mp3 file to cdvfile-path via cordova-plugin-file-transfer
and play it via cordova-plugin-media
.
*Note: See Where to Store Files, File System Layouts and Configuring the Plugin for more details about available fs roots.
To use cdvfile
as a tag' src
you can convert it to native path via toURL()
method of the resolved fileEntry, which you can get via resolveLocalFileSystemURL
- see examples below.
You can also use cdvfile://
paths directly in the DOM, for example:
<img src="cdvfile://localhost/persistent/img/logo.png" />
Note: This method requires following Content Security rules updates:
- Add
cdvfile:
scheme toContent-Security-Policy
meta tag of the index page, e.g.:<meta http-equiv="Content-Security-Policy" content="default-src 'self' data: gap:
cdvfile:https://ssl.gstatic.com 'unsafe-eval'; style-src 'self' 'unsafe-inline'; media-src *">
- Add
<access origin="cdvfile://*" />
toconfig.xml
.
Converting cdvfile:// to native path
resolveLocalFileSystemURL('cdvfile://localhost/temporary/path/to/file.mp4', function(entry) {
var nativePath = entry.toURL();
console.log('Native URI: ' + nativePath);
document.getElementById('video').src = nativePath;
Converting native path to cdvfile://
resolveLocalFileSystemURL(nativePath, function(entry) {
console.log('cdvfile URI: ' + entry.toInternalURL());
Using cdvfile in core plugins
fileTransfer.download(uri, 'cdvfile://localhost/temporary/path/to/file.mp3', function (entry) { ...
var my_media = new Media('cdvfile://localhost/temporary/path/to/file.mp3', ...);
my_media.play();
cdvfile quirks
- Using
cdvfile://
paths in the DOM is not supported on Windows platform (a path can be converted to native instead).
List of Error Codes and Meanings
When an error is thrown, one of the following codes will be used.
Code | Constant |
---|---|
1 | NOT_FOUND_ERR |
2 | SECURITY_ERR |
3 | ABORT_ERR |
4 | NOT_READABLE_ERR |
5 | ENCODING_ERR |
6 | NO_MODIFICATION_ALLOWED_ERR |
7 | INVALID_STATE_ERR |
8 | SYNTAX_ERR |
9 | INVALID_MODIFICATION_ERR |
10 | QUOTA_EXCEEDED_ERR |
11 | TYPE_MISMATCH_ERR |
12 | PATH_EXISTS_ERR |
Configuring the Plugin (Optional)
The set of available filesystems can be configured per-platform. Both iOS and Android recognize a tag in config.xml
which names the filesystems to be installed. By default, all file-system roots are enabled.
<preference name="iosExtraFilesystems" value="library,library-nosync,documents,documents-nosync,cache,bundle,root" />
<preference name="AndroidExtraFilesystems" value="files,files-external,documents,sdcard,cache,cache-external,root" />
Android
files
: The application's internal file storage directoryfiles-external
: The application's external file storage directorysdcard
: The global external file storage directory (this is the root of the SD card, if one is installed). You must have theandroid.permission.WRITE_EXTERNAL_STORAGE
permission to use this.cache
: The application's internal cache directorycache-external
: The application's external cache directoryroot
: The entire device filesystem
Android also supports a special filesystem named "documents", which represents a "/Documents/" subdirectory within the "files" filesystem.
iOS
library
: The application's Library directorydocuments
: The application's Documents directorycache
: The application's Cache directorybundle
: The application's bundle; the location of the app itself on disk (read-only)root
: The entire device filesystem
By default, the library and documents directories can be synced to iCloud. You can also request two additional filesystems, library-nosync
and documents-nosync
, which represent a special non-synced directory within the /Library
or /Documents
filesystem.
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