harmony 鸿蒙Obtaining Application and File System Space Statistics

2023-06-24
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Obtaining Application and File System Space Statistics

This topic describes how to obtain information about the free system space and space occupied by applications so as to prevent insufficient storage space of the system or ensure proper use of quota-controlled cacheDir directories.

Available APIs

For details about the APIs, see ohos.file.statvfs and ohos.file.storageStatistics.

Table 1 APIs for file system and application space statistics

Module	API	Description
\@ohos.file.storageStatistics	getCurrentBundleStats	Obtains the storage space of the current application, in bytes.
\@ohos.file.statvfs	getFreeSize	Obtains the free space of a file system, in bytes.
\@ohos.file.statvfs	getTotalSize	Obtains the total space of a file system, in bytes.

Table 2 Attributes for application space statistics

BundleStats Attribute	Description	Directory for Statistics
appSize	Size of the application installation files, in bytes.	/data/storage/el1/bundle
cacheSize	Size of the application cache files, in bytes.	/data/storage/el1/base/cache /data/storage/el1/base/haps/entry/cache /data/storage/el2/base/cache /data/storage/el2/base/haps/entry/cache
dataSize	Size of the application files (excluding the application installation files and cache files), in bytes.	The application files include local files, distributed files, and database files. - Local application file directories (parent directories of the cache directories): /data/storage/el1/base /data/storage/el2/base - Distributed application directory: /data/storage/el2/distributedfiles - Database directories: /data/storage/el1/database /data/storage/el2/database

Development Example

Obtain the free space of /data of the file system.

  import statvfs from '@ohos.file.statvfs';
  import { BusinessError } from '@ohos.base';
  
  let path = "/data";
  statvfs.getFreeSize(path, (err: BusinessError, number: number) => {
    if (err) {
      console.error(`Invoke getFreeSize failed, code is ${err.code}, message is ${err.message}`);
    } else {
      console.info(`Invoke getFreeSize succeeded, size is ${number}`);
    }
  });

Obtain the space occupied by the current application.

  import storageStatistics from "@ohos.file.storageStatistics";
  import { BusinessError } from '@ohos.base';
  
  storageStatistics.getCurrentBundleStats((err: BusinessError, bundleStats: storageStatistics.BundleStats) => {
    if (err) {
      console.error(`Invoke getCurrentBundleStats failed, code is ${err.code}, message is ${err.message}`);
    } else {
      console.info(`Invoke getCurrentBundleStats succeeded, appsize is ${bundleStats.appSize}`);
    }
  });