fix(fs): writeFile command implementation on Android (tauri-apps#1708)

.changes/fix-fs-write-file-android.md

@@ -0,0 +1,5 @@
+---
+"fs": patch:bug
+---
+
+Fixes `writeFile` command implementation on Android.

plugins/fs/src/commands.rs

@@ -13,6 +13,7 @@ use tauri::{
 };
 
 use std::{
+    borrow::Cow,
     fs::File,
     io::{BufReader, Lines, Read, Write},
     path::{Path, PathBuf},
@@ -105,6 +106,8 @@ pub enum CommandError {
     #[error(transparent)]
     Tauri(#[from] tauri::Error),
     #[error(transparent)]
+    Json(#[from] serde_json::Error),
+    #[error(transparent)]
     Io(#[from] std::io::Error),
     #[error(transparent)]
     UrlParseError(#[from] url::ParseError),
@@ -910,25 +913,31 @@ pub async fn write_file<R: Runtime>(
     command_scope: CommandScope<Entry>,
     request: tauri::ipc::Request<'_>,
 ) -> CommandResult<()> {
-    if let tauri::ipc::InvokeBody::Raw(data) = request.body() {
-        let path = request
-            .headers()
-            .get("path")
-            .ok_or_else(|| anyhow::anyhow!("missing file path").into())
-            .and_then(|p| {
-                p.to_str()
-                    .map_err(|e| anyhow::anyhow!("invalid path: {e}").into())
-            })
-            .and_then(|p| SafeFilePath::from_str(p).map_err(CommandError::from))?;
-        let options = request
-            .headers()
-            .get("options")
-            .and_then(|p| p.to_str().ok())
-            .and_then(|opts| serde_json::from_str(opts).ok());
-        write_file_inner(webview, &global_scope, &command_scope, path, data, options)
-    } else {
-        Err(anyhow::anyhow!("unexpected invoke body").into())
-    }
+    let data = match request.body() {
+        tauri::ipc::InvokeBody::Raw(data) => Cow::Borrowed(data),
+        tauri::ipc::InvokeBody::Json(serde_json::Value::Array(data)) => Cow::Owned(
+            data.iter()
+                .flat_map(|v| v.as_number().and_then(|v| v.as_u64().map(|v| v as u8)))
+                .collect(),
+        ),
+        _ => return Err(anyhow::anyhow!("unexpected invoke body").into()),
+    };
+
+    let path = request
+        .headers()
+        .get("path")
+        .ok_or_else(|| anyhow::anyhow!("missing file path").into())
+        .and_then(|p| {
+            p.to_str()
+                .map_err(|e| anyhow::anyhow!("invalid path: {e}").into())
+        })
+        .and_then(|p| SafeFilePath::from_str(p).map_err(CommandError::from))?;
+    let options = request
+        .headers()
+        .get("options")
+        .and_then(|p| p.to_str().ok())
+        .and_then(|opts| serde_json::from_str(opts).ok());
+    write_file_inner(webview, &global_scope, &command_scope, path, &data, options)
 }
 
 #[tauri::command]