Save blueprint to file (#5491)

### What
* Part of #5294

This adds a command for saving the currently active `.blueprint` file to
disk.


![image](https://github.com/rerun-io/rerun/assets/1148717/706006f1-e440-4402-a73d-b78e4c24a936)


### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
* Using newly built examples:
[app.rerun.io](https://app.rerun.io/pr/5491/index.html)
* Using examples from latest `main` build:
[app.rerun.io](https://app.rerun.io/pr/5491/index.html?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[app.rerun.io](https://app.rerun.io/pr/5491/index.html?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG
* [x] If applicable, add a new check to the [release
checklist](https://github.com/rerun-io/rerun/blob/main/tests/python/release_checklist)!

- [PR Build Summary](https://build.rerun.io/pr/5491)
- [Docs
preview](https://rerun.io/preview/95bfd02278a9a97ec511e87d320ef27d47d479d2/docs)
<!--DOCS-PREVIEW-->
- [Examples
preview](https://rerun.io/preview/95bfd02278a9a97ec511e87d320ef27d47d479d2/examples)
<!--EXAMPLES-PREVIEW-->
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

crates/re_space_view/src/space_view.rs

@@ -553,6 +553,7 @@ mod tests {
         // No overrides set. Everybody has default values.
         {
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],
@@ -595,6 +596,7 @@ mod tests {
         // Parent is not visible, but children are
         {
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],
@@ -643,6 +645,7 @@ mod tests {
         // Nobody is visible
         {
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],
@@ -673,6 +676,7 @@ mod tests {
         {
             let root = space_view.root_data_result(
                 &StoreContext {
+                    app_id: re_log_types::ApplicationId::unknown(),
                     blueprint: &blueprint,
                     recording: Some(&recording),
                     all_recordings: vec![],
@@ -693,6 +697,7 @@ mod tests {
         // Everyone has visible history
         {
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],
@@ -734,6 +739,7 @@ mod tests {
         // Child2 has its own visible history
         {
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],
@@ -1019,6 +1025,7 @@ mod tests {
 
             // Set up a store query and update the overrides.
             let ctx = StoreContext {
+                app_id: re_log_types::ApplicationId::unknown(),
                 blueprint: &blueprint,
                 recording: Some(&recording),
                 all_recordings: vec![],

crates/re_space_view/src/space_view_contents.rs

@@ -628,6 +628,7 @@ mod tests {
             });
 
         let ctx = StoreContext {
+            app_id: re_log_types::ApplicationId::unknown(),
             blueprint: &blueprint,
             recording: Some(&recording),
             all_recordings: vec![],

crates/re_ui/src/command.rs

@@ -16,6 +16,7 @@ pub enum UICommand {
     Open,
     SaveRecording,
     SaveRecordingSelection,
+    SaveBlueprint,
     CloseCurrentRecording,
     #[cfg(not(target_arch = "wasm32"))]
     Quit,
@@ -100,6 +101,8 @@ impl UICommand {
                 "Save data for the current loop selection to a Rerun data file (.rrd)",
             ),
 
+            Self::SaveBlueprint => ("Save blueprint…", "Save the current viewer setup as a Rerun blueprint file (.blueprint)"),
+
             Self::Open => ("Open…", "Open any supported files (.rrd, images, meshes, …)"),
 
             Self::CloseCurrentRecording => (
@@ -245,6 +248,7 @@ impl UICommand {
         match self {
             Self::SaveRecording => Some(cmd(Key::S)),
             Self::SaveRecordingSelection => Some(cmd_alt(Key::S)),
+            Self::SaveBlueprint => None,
             Self::Open => Some(cmd(Key::O)),
             Self::CloseCurrentRecording => None,
 

crates/re_viewer/src/app.rs

@@ -443,16 +443,20 @@ impl App {
     ) {
         match cmd {
             UICommand::SaveRecording => {
-                save(self, store_context, None);
+                save_recording(self, store_context, None);
             }
             UICommand::SaveRecordingSelection => {
-                save(
+                save_recording(
                     self,
                     store_context,
                     self.state.loop_selection(store_context),
                 );
             }
 
+            UICommand::SaveBlueprint => {
+                save_blueprint(self, store_context);
+            }
+
             #[cfg(not(target_arch = "wasm32"))]
             UICommand::Open => {
                 for file_path in open_file_dialog_native() {
@@ -1500,17 +1504,14 @@ async fn async_open_rrd_dialog() -> Vec<re_data_source::FileContents> {
     file_contents
 }
 
-#[allow(clippy::needless_pass_by_ref_mut)]
-fn save(
-    #[allow(unused_variables)] app: &mut App, // only used on native
+fn save_recording(
+    app: &mut App,
     store_context: Option<&StoreContext<'_>>,
     loop_selection: Option<(re_entity_db::Timeline, re_log_types::TimeRangeF)>,
 ) {
-    re_tracing::profile_function!();
-
     let Some(entity_db) = store_context.as_ref().and_then(|view| view.recording) else {
         // NOTE: Can only happen if saving through the command palette.
-        re_log::error!("No data to save!");
+        re_log::error!("No recording data to save");
         return;
     };
 
@@ -1519,9 +1520,44 @@ fn save(
     let title = if loop_selection.is_some() {
         "Save loop selection"
     } else {
-        "Save"
+        "Save recording"
+    };
+
+    save_entity_db(
+        app,
+        file_name.to_owned(),
+        title.to_owned(),
+        entity_db,
+        loop_selection,
+    );
+}
+
+fn save_blueprint(app: &mut App, store_context: Option<&StoreContext<'_>>) {
+    let Some(store_context) = store_context else {
+        re_log::error!("No blueprint to save");
+        return;
     };
 
+    let entity_db = store_context.blueprint;
+
+    let file_name = format!(
+        "{}.blueprint",
+        crate::saving::sanitize_app_id(&store_context.app_id)
+    );
+    let title = "Save blueprint";
+    save_entity_db(app, file_name, title.to_owned(), entity_db, None);
+}
+
+#[allow(clippy::needless_pass_by_ref_mut)] // `app` is only used on native
+fn save_entity_db(
+    #[allow(unused_variables)] app: &mut App, // only used on native
+    file_name: String,
+    title: String,
+    entity_db: &EntityDb,
+    loop_selection: Option<(re_log_types::Timeline, re_log_types::TimeRangeF)>,
+) {
+    re_tracing::profile_function!();
+
     // Web
     #[cfg(target_arch = "wasm32")]
     {
@@ -1534,7 +1570,7 @@ fn save(
         };
 
         wasm_bindgen_futures::spawn_local(async move {
-            if let Err(err) = async_save_dialog(file_name, title, &messages).await {
+            if let Err(err) = async_save_dialog(&file_name, &title, &messages).await {
                 re_log::error!("File saving failed: {err}");
             }
         });
@@ -1558,10 +1594,10 @@ fn save(
                     return;
                 }
             };
-            if let Err(err) = app
-                .background_tasks
-                .spawn_file_saver(move || crate::saving::encode_to_file(&path, messages.iter()))
-            {
+            if let Err(err) = app.background_tasks.spawn_file_saver(move || {
+                crate::saving::encode_to_file(&path, messages.iter())?;
+                Ok(path)
+            }) {
                 // NOTE: Can only happen if saving through the command palette.
                 re_log::error!("File saving failed: {err}");
             }

crates/re_viewer/src/background_tasks.rs

@@ -44,10 +44,9 @@ impl BackgroundTasks {
     }
 
     #[cfg(not(target_arch = "wasm32"))]
-    pub fn spawn_file_saver<F, T>(&mut self, f: F) -> anyhow::Result<()>
+    pub fn spawn_file_saver<F>(&mut self, f: F) -> anyhow::Result<()>
     where
-        F: FnOnce() -> T + Send + 'static,
-        T: Send + 'static,
+        F: FnOnce() -> anyhow::Result<PathBuf> + Send + 'static,
     {
         self.spawn_threaded_promise(FILE_SAVER_PROMISE, f)
     }

crates/re_viewer/src/saving.rs

@@ -1,21 +1,19 @@
-#[cfg(not(target_arch = "wasm32"))]
 use re_log_types::ApplicationId;
 
-#[cfg(not(target_arch = "wasm32"))]
 /// Convert to lowercase and replace any character that is not a fairly common
 /// filename character with '-'
-fn sanitize_app_id(app_id: &ApplicationId) -> String {
+pub fn sanitize_app_id(app_id: &ApplicationId) -> String {
     let output = app_id.0.to_lowercase();
     output.replace(
         |c: char| !matches!(c, '0'..='9' | 'a'..='z' | '.' | '_' | '+' | '(' | ')' | '[' | ']'),
         "-",
     )
 }
 
-#[cfg(not(target_arch = "wasm32"))]
 /// Determine the default path for a blueprint based on its `ApplicationId`
 /// This path should be deterministic and unique.
 // TODO(#2579): Implement equivalent for web
+#[cfg(not(target_arch = "wasm32"))]
 pub fn default_blueprint_path(app_id: &ApplicationId) -> anyhow::Result<std::path::PathBuf> {
     use anyhow::Context;
 

crates/re_viewer/src/store_hub.rs

@@ -90,33 +90,28 @@ impl StoreHub {
     /// matching [`ApplicationId`].
     pub fn read_context(&mut self) -> Option<StoreContext<'_>> {
         // If we have an app-id, then use it to look up the blueprint.
-        let blueprint_id = self.selected_application_id.as_ref().map(|app_id| {
-            self.blueprint_by_app_id
-                .entry(app_id.clone())
-                .or_insert_with(|| StoreId::from_string(StoreKind::Blueprint, app_id.clone().0))
-        });
+        let app_id = self.selected_application_id.clone()?;
+
+        let blueprint_id = self
+            .blueprint_by_app_id
+            .entry(app_id.clone())
+            .or_insert_with(|| StoreId::from_string(StoreKind::Blueprint, app_id.clone().0));
 
-        // As long as we have a blueprint-id, create the blueprint.
-        blueprint_id
+        // Get or create the blueprint:
+        self.store_bundle.blueprint_entry(blueprint_id);
+        let blueprint = self.store_bundle.blueprint(blueprint_id)?;
+
+        let recording = self
+            .selected_rec_id
             .as_ref()
-            .map(|id| self.store_bundle.blueprint_entry(id));
-
-        // If we have a blueprint, we can return the `StoreContext`. In most
-        // cases it should have already existed or been created above.
-        blueprint_id
-            .and_then(|id| self.store_bundle.blueprint(id))
-            .map(|blueprint| {
-                let recording = self
-                    .selected_rec_id
-                    .as_ref()
-                    .and_then(|id| self.store_bundle.recording(id));
-
-                StoreContext {
-                    blueprint,
-                    recording,
-                    all_recordings: self.store_bundle.recordings().collect_vec(),
-                }
-            })
+            .and_then(|id| self.store_bundle.recording(id));
+
+        Some(StoreContext {
+            app_id,
+            blueprint,
+            recording,
+            all_recordings: self.store_bundle.recordings().collect_vec(),
+        })
     }
 
     /// Keeps track if a recording was ever activated.

crates/re_viewer/src/ui/rerun_menu.rs

@@ -40,6 +40,8 @@ impl App {
 
             self.save_buttons_ui(ui, _store_context);
 
+            UICommand::SaveBlueprint.menu_button_ui(ui, &self.command_sender);
+
             UICommand::CloseCurrentRecording.menu_button_ui(ui, &self.command_sender);
 
             ui.add_space(SPACING);
@@ -165,13 +167,13 @@ impl App {
 
         let file_save_in_progress = self.background_tasks.is_file_save_in_progress();
 
-        let save_button = UICommand::SaveRecording.menu_button(ui.ctx());
+        let save_recording_button = UICommand::SaveRecording.menu_button(ui.ctx());
         let save_selection_button = UICommand::SaveRecordingSelection.menu_button(ui.ctx());
 
         if file_save_in_progress {
             ui.add_enabled_ui(false, |ui| {
                 ui.horizontal(|ui| {
-                    ui.add(save_button);
+                    ui.add(save_recording_button);
                     ui.spinner();
                 });
                 ui.horizontal(|ui| {
@@ -185,7 +187,7 @@ impl App {
                 .map_or(false, |recording| !recording.is_empty());
             ui.add_enabled_ui(entity_db_is_nonempty, |ui| {
                 if ui
-                    .add(save_button)
+                    .add(save_recording_button)
                     .on_hover_text("Save all data to a Rerun data file (.rrd)")
                     .clicked()
                 {

crates/re_viewer_context/src/store_context.rs

@@ -1,7 +1,9 @@
 use re_entity_db::EntityDb;
+use re_log_types::ApplicationId;
 
 /// The current Blueprint and Recording being displayed by the viewer
 pub struct StoreContext<'a> {
+    pub app_id: ApplicationId,
     pub blueprint: &'a EntityDb,
     pub recording: Option<&'a EntityDb>,
     pub all_recordings: Vec<&'a EntityDb>,