250495 2023-01-11 19:57:04 -0800 Data written via FileSystemSyncAccessHandle disappears after creating new FileSystemFileHandle 2023-01-13 09:29:51 -0800 1 1 1 Unclassified WebKit Website Storage Safari 16 All Unspecified RESOLVED FIXED BrowserCompat, InRadar P2 Normal --- 1 03_placid_daft sihui_liu karlcow sihui_liu webkit-bug-importer oldest_to_newest 1924972 0 03_placid_daft 2023-01-11 19:57:04 -0800 With many attempts, I could not find a way to persist written data to FileSystemSyncAccessHandle. The example from https://webkit.org/blog/12257/the-file-system-access-api-with-origin-private-file-system/ article works only if you try to getFile/read data from the same instance of FileSystemFileHandle, when you get a new instance of FileHandle all data disappears. This can be easily reproduced with a slight modification to the existing LayoutTest at: https://github.com/WebKit/WebKit/blob/3729059e6a040c8c168679975c9d04dab48e5a4d/LayoutTests/storage/filesystemaccess/resources/file-handle-getfile.js#L44 If before `fileObject = await fileHandle.getFile();` line you place `fileHandle = await rootHandle.getFileHandle("file-handle-getfile.txt", { "create" : false });` you will not get any actual data in return, even if you add accessHandle.flush() call before accessHandle.close(); This works perfectly fine in Chrome but not in WebKit. FileSystemSyncAccessHandle is the only available way to write data in WebKit but it's not working because it does not persist data. 1924975 1 03_placid_daft 2023-01-11 20:22:13 -0800 More clear information on how to reproduce: In file: https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/filesystemaccess/resources/file-handle-getfile.js replace test function with: ``` async function test() { try { var rootHandle = await navigator.storage.getDirectory(); // Create a new file for this test. await rootHandle.removeEntry("file-handle-getfile.txt").then(() => { }, () => { }); fileHandle = await rootHandle.getFileHandle("file-handle-getfile.txt", { "create" : true }); fileContent = ""; // Write file content in worker. if (typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope) { console.log('hello from WebWorker') accessHandle = await fileHandle.createSyncAccessHandle(); const encoder = new TextEncoder(); fileContent = "This is a test."; writeBuffer = encoder.encode(fileContent); writeSize = accessHandle.write(writeBuffer, { "at" : 0 }); shouldBe("writeSize", "writeBuffer.byteLength"); accessHandle.flush(); // This is a new line accessHandle.close(); } fileHandle = await rootHandle.getFileHandle("file-handle-getfile.txt"); // This is a new line fileObject = await fileHandle.getFile(); readText = await read(fileObject); shouldBe("readText", "fileContent"); finishTest(); } catch (error) { finishTest(error.toString()); } } ``` Then run LayoutTest: https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/filesystemaccess/file-handle-getfile-worker.html 1925099 2 sihui_liu 2023-01-12 11:26:36 -0800 (In reply to Alex Titarenko from comment #1) > More clear information on how to reproduce: > > In file: > https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/ > filesystemaccess/resources/file-handle-getfile.js > > replace test function with: > > ``` > async function test() > { > try { > var rootHandle = await navigator.storage.getDirectory(); > // Create a new file for this test. > await rootHandle.removeEntry("file-handle-getfile.txt").then(() => { > }, () => { }); > fileHandle = await > rootHandle.getFileHandle("file-handle-getfile.txt", { "create" : true }); > fileContent = ""; > > // Write file content in worker. > if (typeof WorkerGlobalScope !== 'undefined' && self instanceof > WorkerGlobalScope) { > console.log('hello from WebWorker') > accessHandle = await fileHandle.createSyncAccessHandle(); > const encoder = new TextEncoder(); > fileContent = "This is a test."; > writeBuffer = encoder.encode(fileContent); > writeSize = accessHandle.write(writeBuffer, { "at" : 0 }); > shouldBe("writeSize", "writeBuffer.byteLength"); > accessHandle.flush(); // This is a new line > accessHandle.close(); > } > > fileHandle = await > rootHandle.getFileHandle("file-handle-getfile.txt"); // This is a new line > fileObject = await fileHandle.getFile(); > readText = await read(fileObject); > shouldBe("readText", "fileContent"); > > finishTest(); > } catch (error) { > finishTest(error.toString()); > } > } > ``` > > Then run LayoutTest: > https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/ > filesystemaccess/file-handle-getfile-worker.html 1925100 3 sihui_liu 2023-01-12 11:28:12 -0800 (In reply to Alex Titarenko from comment #1) > More clear information on how to reproduce: > > In file: > https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/ > filesystemaccess/resources/file-handle-getfile.js > > replace test function with: > > ``` > async function test() > { > try { > var rootHandle = await navigator.storage.getDirectory(); > // Create a new file for this test. > await rootHandle.removeEntry("file-handle-getfile.txt").then(() => { > }, () => { }); > fileHandle = await > rootHandle.getFileHandle("file-handle-getfile.txt", { "create" : true }); > fileContent = ""; > > // Write file content in worker. > if (typeof WorkerGlobalScope !== 'undefined' && self instanceof > WorkerGlobalScope) { > console.log('hello from WebWorker') > accessHandle = await fileHandle.createSyncAccessHandle(); > const encoder = new TextEncoder(); > fileContent = "This is a test."; > writeBuffer = encoder.encode(fileContent); > writeSize = accessHandle.write(writeBuffer, { "at" : 0 }); > shouldBe("writeSize", "writeBuffer.byteLength"); > accessHandle.flush(); // This is a new line > accessHandle.close(); > } > > fileHandle = await > rootHandle.getFileHandle("file-handle-getfile.txt"); // This is a new line > fileObject = await fileHandle.getFile(); > readText = await read(fileObject); > shouldBe("readText", "fileContent"); > > finishTest(); > } catch (error) { > finishTest(error.toString()); > } > } > ``` > > Then run LayoutTest: > https://github.com/WebKit/WebKit/blob/main/LayoutTests/storage/ > filesystemaccess/file-handle-getfile-worker.html Thanks for the report. I think it's caused by file being truncated unexpectedly on FileSystemHandle creation. Will make a fix. 1925101 4 webkit-bug-importer 2023-01-12 11:29:25 -0800 <rdar://problem/104187327> 1925102 5 sihui_liu 2023-01-12 11:32:28 -0800 Pull request: https://github.com/WebKit/WebKit/pull/8586 1925369 6 ews-feeder 2023-01-13 09:29:48 -0800 Committed 258876@main (60a6090b4106): <https://commits.webkit.org/258876@main> Reviewed commits have been landed. Closing PR #8586 and removing active labels.