Visualization Registry (https://github.com/enso-org/ide/pull/429)

* Implement registry.
* Refactor code to use a trait `Class` as the builder of `Visualization`s.

Original commit: 48b8d88dc3

gui/src/rust/lib/graph-editor/src/component/visualization.rs

@@ -1,29 +1,36 @@
 //! This module defines the visualization widgets and related functionality.
 //!
-//! The overall architecture of visualizations consists of three parts:
+//! The overall architecture of visualizations consists of four parts:
 //!
 //! 1. The `DataRenderer` trait provides the functionality to render the actual visualization view
 //!    that implements `display::Object`. It is provided with data and itself provides frp streams
 //!    of its output if there is some, for example, if it acts as a widget.
 //!
 //! 2. The `Visualization` is a struct that wraps the `DataRenderer` and implements the generic
-//!    tasks that are the same for all visualisations. That is, interfacing with the other UI
+//!    tasks that are the same for all visualizations. That is, interfacing with the other UI
 //!    elements, the visualization registry, as well as propagating frp messages.
 //!
-//! 3. The `Container` wraps the `Visualisation` and provides the UI elements that facilitate
-//!    user interactions. For example, selecting a visualisation or connecting it to nodes in the
+//! 3. The `Class` is a struct that can instantiate multiple `Visualization` structs and provides
+//!    data about the visualization even before they are instantiated like input datatype and name.
+//!
+//! 4. The `Container` wraps the `Visualization` and provides the UI elements that facilitate
+//!    user interactions. For example, selecting a visualization or connecting it to nodes in the
 //!    graph editor scene.
 //!
 //! In addition this module also contains a `Data` struct that provides a dynamically typed way to
-//! handle data for visualisations. This allows the `Visualisation` struct to be without type
+//! handle data for visualizations. This allows the `Visualization` struct to be without type
 //! parameters and simplifies the FRP communication and complexity of the node system.
 
 pub mod class;
 pub mod container;
-pub mod renderer;
 pub mod data;
+pub mod js;
+pub mod registry;
+pub mod renderer;
 
 pub use class::*;
-pub use data::*;
 pub use container::*;
+pub use data::*;
+pub use js::*;
+pub use registry::*;
 pub use renderer::*;

gui/src/rust/lib/graph-editor/src/component/visualization/class.rs

@@ -5,8 +5,9 @@ use crate::prelude::*;
 use crate::frp;
 use crate::visualization::*;
 
+use ensogl::display::Scene;
 use ensogl::display;
-
+use std::error::Error;
 
 
 // ====================
@@ -20,11 +21,31 @@ pub struct EnsoCode {
 }
 
 /// Type alias for a string representing an enso type.
-#[derive(Clone,CloneRef,Debug)]
+#[derive(Clone,CloneRef,Debug,PartialEq,Eq,Hash)]
 pub struct EnsoType {
     content: Rc<String>
 }
 
+impl From<String> for EnsoType {
+    fn from(source:String) -> Self {
+        EnsoType { content:Rc::new(source) }
+    }
+}
+
+impl From<&str> for EnsoType {
+    fn from(source:&str) -> Self {
+        EnsoType { content:Rc::new(source.to_string()) }
+    }
+}
+
+/// Contains general information about a visualization.
+#[derive(Clone,Debug)]
+#[allow(missing_docs)]
+pub struct Signature {
+    pub name        : String,
+    pub input_types : Vec<EnsoType>,
+}
+
 
 
 // =========================
@@ -145,7 +166,6 @@ impl Visualization {
                 frp.preprocess_change.emit(data.as_ref().map(|code|code.clone_ref()))
             }));
         }
-
         self
     }
 
@@ -154,3 +174,138 @@ impl Visualization {
         self.state.renderer.set_size(size)
     }
 }
+
+
+
+// ===========================
+// === Visualization Class ===
+// ===========================
+
+/// Indicates that instantiating a `Visualisation` from a `Class` has failed.
+#[derive(Debug,Display)]
+#[allow(missing_docs)]
+pub enum InstantiationError {
+    /// Indicates a problem with instantiating a class object.
+    InvalidClass         { inner:Box<dyn Error> },
+    /// Indicates a problem with instantiating a visualisation from a valid class object.
+    InvalidVisualisation { inner:Box<dyn Error> },
+}
+
+/// Result of the attempt to instantiate a `Visualization` from a `Class`.
+pub type InstantiationResult = Result<Visualization,InstantiationError>;
+
+/// Specifies a trait that allows the instantiation of `Visualizations`.
+///
+/// The `Class` provides a way to implement structs that allow the instantiation of specific
+/// visualizations, while already providing general information that doesn't require an
+/// instantiated visualization, for example, the name or input type of the visualization.
+///
+/// There are two example implementations: The `JsSourceClass`, which is based on a JS snippet to
+/// instantiate `JsRenderer`, and the fairly generic `NativeConstructorClass`, that only requires
+/// a function that can create a InstantiationResult. The later can be used as a thin wrapper around
+/// the constructor methods of native visualizations.
+///
+/// Example
+/// --------
+/// ```no_run
+/// use graph_editor::component::visualization;
+/// use graph_editor::component::visualization::Visualization;
+/// use graph_editor::component::visualization::renderer::example::native::BubbleChart;
+/// use ensogl::display::Scene;
+/// use std::rc::Rc;
+///
+/// // Create a `visualization::Class` from a JS source code snippet.
+/// let js_source_class = visualization::JsSourceClass::from_js_source_raw(r#"
+///
+///    class BubbleVisualization {
+///         static inputTypes = ["[[Float,Float,Float]]"]
+///         onDataReceived(root, data) {}
+///         setSize(root, size) {}
+///     }
+///
+///     return BubbleVisualization;
+///
+/// "#.into());
+///
+/// // Create a `visualization::Class` that instantiates a `BubbleChart`.
+/// let native_bubble_vis_class = visualization::NativeConstructorClass::new(
+///     visualization::Signature {
+///         name        : "Bubble Visualization (native)".to_string(),
+///         input_types : vec!["[[Float,Float,Float]]".into()],
+///     },
+///     |scene:&Scene| Ok(Visualization::new(BubbleChart::new(scene)))
+/// );
+/// ```
+pub trait Class: Debug {
+    /// Provides additional information about the `Class`, for example, which `DataType`s can be
+    /// rendered by the instantiated visualization.
+    fn signature(&self) -> &Signature;
+    /// Create new visualization, that is initialised for the given scene. This can fail if the
+    /// `visualization::Class` contains invalid data, for example, JS code that fails to execute,
+    /// or if the scene is in an invalid state.
+    // TODO consider not providing the scene here, but hooking the the shapes/dom elements into the
+    // scene externally.
+    fn instantiate(&self, scene:&Scene) -> InstantiationResult;
+}
+
+/// Wrapper for `Class` objects, so they can be passed through the FRP system.
+#[derive(Clone,Debug,Default)]
+#[allow(missing_docs)]
+pub struct Handle {
+    class : Option<Rc<dyn Class>>
+}
+
+impl Handle {
+    /// Constructor.
+    pub fn new<T:Class+'static>(class:T) -> Handle {
+        let class = Rc::new(class);
+        Handle {class:Some(class)}
+    }
+
+    /// Return the inner class.
+    pub fn class(&self) -> Option<Rc<dyn Class>> {
+        self.class.clone()
+    }
+}
+
+impl CloneRef for Handle {}
+
+
+
+// ================================
+// === Native Constructor Class ===
+// ================================
+
+/// Type alias for a function that can create a `Visualization`.
+pub trait VisualizationConstructor = Fn(&Scene) -> InstantiationResult;
+
+/// Constructor that instantiates visualisations from a given `VisualizationConstructor`. Can be
+/// used to wrap the constructor of visualizations defined in Rust.
+#[derive(CloneRef,Clone,Derivative)]
+#[derivative(Debug)]
+#[allow(missing_docs)]
+pub struct NativeConstructorClass {
+    info        : Rc<Signature>,
+    #[derivative(Debug="ignore")]
+    constructor : Rc<dyn VisualizationConstructor>,
+}
+
+impl NativeConstructorClass {
+    /// Create a visualization source from a closure that returns a `Visualization`.
+    pub fn new<T>(info:Signature, constructor:T) -> Self
+    where T: VisualizationConstructor + 'static {
+        let info        = Rc::new(info);
+        let constructor = Rc::new(constructor);
+        NativeConstructorClass{info,constructor}
+    }
+}
+
+impl Class for NativeConstructorClass {
+    fn signature(&self) -> &Signature {
+        &self.info
+    }
+
+    fn instantiate(&self, scene:&Scene) -> InstantiationResult {
+        self.constructor.call((scene,))
+    }
+}

gui/src/rust/lib/graph-editor/src/component/visualization/container.rs

@@ -46,7 +46,7 @@ impl Default for ContainerFrp {
 
 /// Container that wraps a `Visualization` for rendering and interaction in the GUI.
 ///
-/// The API to interact with the visualisation is exposed through the `ContainerFrp`.
+/// The API to interact with the visualization is exposed through the `ContainerFrp`.
 #[derive(Clone,CloneRef,Debug,Shrinkwrap)]
 #[allow(missing_docs)]
 pub struct Container {
@@ -72,7 +72,7 @@ pub struct ContainerData {
 }
 
 impl ContainerData {
-    /// Set whether the visualisation should be visible or not.
+    /// Set whether the visualization should be visible or not.
     pub fn set_visibility(&self, is_visible:bool) {
         if let Some(vis) = self.visualization.borrow().as_ref() {
             if is_visible {
@@ -83,7 +83,7 @@ impl ContainerData {
         }
     }
 
-    /// Indicates whether the visualisation is visible.
+    /// Indicates whether the visualization is visible.
     fn is_visible(&self) -> bool {
         if let Some(vis) = self.visualization.borrow().as_ref() {
             vis.has_parent()
@@ -99,8 +99,8 @@ impl ContainerData {
 
     /// Update the content properties with the values from the `ContainerData`.
     ///
-    /// Needs to called when a visualisation has been set.
-    fn init_visualisation_properties(&self) {
+    /// Needs to called when a visualization has been set.
+    fn init_visualization_properties(&self) {
         let size         = self.size.get();
         if let Some(vis) = self.visualization.borrow().as_ref() {
             vis.set_size(size);
@@ -109,10 +109,10 @@ impl ContainerData {
     }
 
     /// Set the visualization shown in this container..
-    fn set_visualisation(&self, visualization:Visualization) {
+    fn set_visualization(&self, visualization:Visualization) {
         self.add_child(&visualization);
         self.visualization.replace(Some(visualization));
-        self.init_visualisation_properties();
+        self.init_visualization_properties();
     }
 }
 
@@ -152,9 +152,9 @@ impl Container {
                 container_data.toggle_visibility()
             }));
 
-            def _f_set_vis = frp.set_visualization.map(f!([container_data](visualisation) {
-                if let Some(visualisation) = visualisation.as_ref() {
-                    container_data.set_visualisation(visualisation.clone());
+            def _f_set_vis = frp.set_visualization.map(f!([container_data](visualization) {
+                if let Some(visualization) = visualization.as_ref() {
+                    container_data.set_visualization(visualization.clone());
                 }
             }));
 

gui/src/rust/lib/graph-editor/src/component/visualization/data.rs

@@ -9,13 +9,13 @@ use serde::Deserialize;
 
 
 // ======================================
-// === Wrapper for Visualisation Data ===
+// === Wrapper for Visualization Data ===
 // =======================================
 
 /// Type indicator
 pub type DataType = EnsoType;
 
-/// Wrapper for data that can be consumed by a visualisation.
+/// Wrapper for data that can be consumed by a visualization.
 /// TODO[mm] consider static versus dynamic typing for visualizations and data!
 #[derive(Clone,CloneRef,Debug)]
 #[allow(missing_docs)]
@@ -70,7 +70,7 @@ impl Data {
 pub enum DataError {
     /// Indicates that that the provided data type does not match the expected data type.
     InvalidDataType,
-    /// The data caused an error in the computation of the visualisation.
+    /// The data caused an error in the computation of the visualization.
     InternalComputationError,
 }
 

gui/src/rust/lib/graph-editor/src/component/visualization/js.rs

@@ -0,0 +1,133 @@
+//! This module contains functionality to create a `Class` object from a JS source strings.
+
+use crate::prelude::*;
+
+use crate::component::visualization::JsVisualizationError;
+use crate::component::visualization::InstantiationError;
+use crate::component::visualization::JsRenderer;
+use crate::component::visualization::JsResult;
+use crate::component::visualization::InstantiationResult;
+use crate::component::visualization::Class;
+use crate::component::visualization::Visualization;
+use crate::component::visualization::Signature;
+use crate::component::visualization::EnsoType;
+
+use ensogl::display::Scene;
+use ensogl::system::web::JsValue;
+use js_sys;
+
+
+
+// ===================================
+// === Visualization Class Wrapper ===
+// ===================================
+
+/// Internal wrapper for the a JS class that implements our visualization specification. Provides
+/// convenience functions for accessing JS methods and signature.
+#[derive(Clone,Debug)]
+#[allow(missing_docs)]
+struct VisualizationClassWrapper {
+    class: JsValue,
+}
+
+impl VisualizationClassWrapper {
+    fn instantiate_class(source:&str) -> JsResult<VisualizationClassWrapper> {
+        let context     = JsValue::NULL;
+        let constructor = js_sys::Function::new_no_args(source);
+        let class       = constructor.call0(&context)?;
+        Ok(VisualizationClassWrapper{class})
+    }
+
+    fn signature(&self) -> JsResult<Signature> {
+        let input_types = self.input_types().unwrap_or_default();
+        let name        = self.name()?;
+        Ok(Signature {name,input_types})
+    }
+
+    fn constructor(&self) -> JsResult<js_sys::Function> {
+        Ok(js_sys::Reflect::get(&self.prototype()?,&"constructor".into())?.into())
+    }
+
+    fn prototype(&self) -> JsResult<JsValue> {
+        Ok(js_sys::Reflect::get(&self.class,&"prototype".into())?)
+    }
+
+    fn input_types(&self) -> JsResult<Vec<EnsoType>> {
+        let input_types            = js_sys::Reflect::get(&self.class, &"inputTypes".into())?;
+        let input_types            = js_sys::Array::from(&input_types);
+        let js_string_to_enso_type = |value:JsValue| {Some(EnsoType::from(value.as_string()?))};
+        Ok(input_types.iter().filter_map(js_string_to_enso_type).collect())
+    }
+
+    fn name(&self) -> JsResult<String> {
+        let constructor = self.constructor()?;
+        let name        = js_sys::Reflect::get(&constructor,&"name".into())?;
+        Ok(name.as_string().unwrap_or_default())
+    }
+
+    fn instantiate(&self) -> JsResult<JsValue> {
+        let fn_wrapper = js_sys::Function::new_with_args("cls", "return new cls()");
+        let context    = JsValue::NULL;
+        Ok(fn_wrapper.call1(&context, &self.class)?)
+    }
+}
+
+
+
+// ========================
+// === Js Source Class  ===
+// ========================
+
+/// Implements the `visualization::Class` for a JS source string.
+///
+/// Example
+/// -------
+/// ```no_run
+///
+/// # use graph_editor::component::visualization::JsSourceClass;
+///
+/// JsSourceClass::from_js_source_raw(r#"
+///     class Visualization {
+///         static inputTypes = ["[[Float,Float,Float]]"]
+///         onDataReceived(root, data) {}
+///         setSize(root, size) {}
+///     }
+///     return Visualizations;
+/// "#.into()).unwrap();
+/// ```
+#[derive(CloneRef,Clone,Debug)]
+#[allow(missing_docs)]
+pub struct JsSourceClass {
+    js_class   : Rc<VisualizationClassWrapper>,
+    signature: Rc<Signature>,
+}
+
+impl JsSourceClass {
+    /// Create a visualization source from piece of JS source code. Signature needs to be inferred.
+    pub fn from_js_source_raw(source:&str) -> Result<Self,JsVisualizationError> {
+        let js_class   = VisualizationClassWrapper::instantiate_class(&source)?;
+        let signature  = js_class.signature()?;
+        let js_class   = Rc::new(js_class);
+        let signature  = Rc::new(signature);
+        Ok(JsSourceClass{js_class,signature})
+    }
+}
+
+impl Class for JsSourceClass {
+    fn signature(&self) -> &Signature {
+        &self.signature
+    }
+
+    fn instantiate(&self, scene:&Scene) -> InstantiationResult {
+        let obj = match self.js_class.instantiate() {
+            Ok(obj) => obj,
+            Err(err) => return Err(InstantiationError::InvalidClass {inner:err.into()}),
+        };
+        let renderer = match JsRenderer::from_object(obj) {
+            Ok(renderer) => renderer,
+            Err(err) => return Err(InstantiationError::InvalidClass {inner:err.into()}),
+        };
+        renderer.set_dom_layer(&scene.dom.layers.front);
+        Ok(Visualization::new(renderer))
+    }
+}

gui/src/rust/lib/graph-editor/src/component/visualization/registry.rs

@@ -0,0 +1,102 @@
+//! The `Registry` provides a mechanism to store `visualization::Class`es for all available visualizations. It
+//! provides functionality to register new factories, as well as get suitable factories for
+//! a specific data type.
+//!
+//! Example
+//! --------
+//! ```no_run
+//! use graph_editor::component::visualization::Registry;
+//! use graph_editor::component::visualization::EnsoType;
+//! use graph_editor::component::visualization::JsSourceClass;
+//!
+//! // Instantiate a pre-populated registry.
+//! let registry = Registry::with_default_visualizations();
+//! // Add a new class that creates visualizations defined in JS.
+//! registry.register_class(JsSourceClass::from_js_source_raw(r#"
+//!     class BubbleVisualization {
+//!         static inputTypes = ["[[Float,Float,Float]]"]
+//!         onDataReceived(root, data) {}
+//!         setSize(root, size) {}
+//!     }
+//!     return BubbleVisualization;
+//! "#.into()).unwrap());
+//!
+//! // Get all factories that can render  visualization for the type `[[Float,Float,Float]]`.
+//! let target_type:EnsoType = "[[Float,Float,Float]]".to_string().into();
+//! assert!(registry.valid_sources(&target_type).len() > 0);
+//! ```
+
+use crate::prelude::*;
+
+use crate::component::visualization::*;
+use crate::component::visualization::renderer::example::js::get_bubble_vis_class;
+use crate::component::visualization::renderer::example::native::BubbleChart;
+
+use ensogl::display::scene::Scene;
+
+
+
+// ==============================
+// === Visualization Registry ===
+// ==============================
+
+/// HashMap that contains the mapping from `EnsoType`s to a `Vec` of `Factories. This is meant to
+/// map a `EnsoType` to all `visualization::Class`es that support visualising that type.
+type RegistryTypeMap = HashMap<EnsoType, Vec<Rc<dyn Class>>>;
+
+/// The registry struct. For more information see the module description.
+#[derive(Clone,CloneRef,Default,Debug)]
+#[allow(missing_docs)]
+pub struct Registry {
+    entries : Rc<RefCell<RegistryTypeMap>>,
+}
+
+impl Registry {
+    /// Return an empty `Registry`.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Return a `Registry` prepopulated with default visualizations.
+    pub fn with_default_visualizations() -> Self {
+        let registry = Self::new();
+        // FIXME use proper enso types here.
+        registry.register_class(NativeConstructorClass::new(
+            Signature {
+                name        : "Bubble Visualization (native)".to_string(),
+                input_types : vec!["[[Float,Float,Float]]".to_string().into()],
+            },
+            |scene:&Scene| Ok(Visualization::new(BubbleChart::new(scene)))
+        ));
+        registry.register_class(get_bubble_vis_class());
+
+        registry
+    }
+
+    /// Register a new visualization class with the registry.
+    pub fn register_class<T:Class+'static>(&self, class:T) {
+        self.register_class_rc(Rc::new(class));
+    }
+
+    /// Register a new visualization class that's pre-wrapped in an `Rc` with the registry.
+    pub fn register_class_from_handle(&self, handle:&Handle) {
+        if let Some(class) = handle.class() {
+            self.register_class_rc(class);
+        }
+    }
+
+    fn register_class_rc(&self, class:Rc<dyn Class>) {
+        let spec = class.signature();
+        for dtype in &spec.input_types {
+            let mut entries = self.entries.borrow_mut();
+            let entry_vec = entries.entry(dtype.clone()).or_insert_with(default);
+            entry_vec.push(Rc::clone(&class));
+        }
+    }
+
+    /// Return all `visualization::Class`es that can create a visualization for the given datatype.
+    pub fn valid_sources(&self, dtype:&EnsoType) -> Vec<Rc<dyn Class>>{
+        let entries       = self.entries.borrow();
+        entries.get(dtype).cloned().unwrap_or_else(default)
+    }
+}

gui/src/rust/lib/graph-editor/src/component/visualization/renderer/class.rs

@@ -19,7 +19,7 @@ use ensogl::display;
 pub struct DataRendererFrp {
     pub network   : frp::Network,
     /// This is emitted if the state of the renderer has been changed by UI interaction.
-    /// It contains the output data of this visualisation if there is some.
+    /// It contains the output data of this visualization if there is some.
     pub on_change            : frp::Stream<Option<EnsoCode>>,
     /// Will be emitted if the visualization changes it's preprocessor. Transmits the new
     /// preprocessor code.
@@ -53,7 +53,7 @@ impl Default for DataRendererFrp {
 /// producing a `display::Object` that will be shown in the scene. It will create FRP events to
 /// indicate updates to its output data (e.g., through user interaction).
 ///
-/// A DataRenderer can indicate what kind of data it can use to create a visualisation through the
+/// A DataRenderer can indicate what kind of data it can use to create a visualization through the
 /// `valid_input_types` method. This serves as a hint, it will also reject invalid input in the
 /// `set_data` method with a `DataError`. The owner of the `DataRenderer` is in charge of producing
 /// UI feedback to indicate a problem with the data.
@@ -67,7 +67,7 @@ pub trait DataRenderer: display::Object + Debug {
     /// processed by this `DataRenderer`, if the data is of an invalid data type, it violates other
     /// assumptions of this `DataRenderer`, a `DataError` is returned.
     fn receive_data(&self, data:Data) -> Result<(), DataError>;
-    /// Set the size of viewport of the visualization. The visualisation must not render outside of
+    /// Set the size of viewport of the visualization. The visualization must not render outside of
     /// this viewport.
     fn set_size(&self, size:Vector2<f32>);
 

gui/src/rust/lib/graph-editor/src/component/visualization/renderer/example.rs

@@ -1,4 +1,4 @@
-//! The `example` modules contains some examples of visualisations.
+//! The `example` modules contains some examples of visualizations.
 //! TODO further describe the examples, how they work and how to extend them.
 
 pub mod native;

gui/src/rust/lib/graph-editor/src/component/visualization/renderer/example/js.rs

@@ -1,104 +1,15 @@
-//! Example of the visualisation JS wrapper API usage
+//! Example of the visualization JS wrapper API usage
 // TODO remove once we have proper visualizations or replace with a nice d3 example.
 // These implementations are neither efficient nor pretty, but get the idea across.
 
-use crate::component::visualization::JsRenderer;
+use crate::component::visualization::JsSourceClass;
 
-/// Returns a simple bubble chart implemented in vanilla JS. uses single functions to implement the
-/// visualization.
-pub fn function_sample_js_bubble_chart() -> JsRenderer {
-    let fn_set_data = r#"{
-        const xmlns = "http://www.w3.org/2000/svg";
-        const root = arguments[0];
-        while (root.firstChild) {
-             root.removeChild(root.lastChild);
-        }
-
-        const svgElem = document.createElementNS(xmlns, "svg");
-        svgElem.setAttributeNS(null, "id"     , "vis-svg");
-        svgElem.setAttributeNS(null, "viewBox", "0 0 " + 100 + " " + 100);
-        svgElem.setAttributeNS(null, "width"  , 100);
-        svgElem.setAttributeNS(null, "height" , 100);
-        root.appendChild(svgElem);
-
-        const data = arguments[1];
-        data.forEach(data => {
-            const bubble = document.createElementNS(xmlns,"circle");
-            bubble.setAttributeNS(null,"stroke", "black");
-            bubble.setAttributeNS(null,"fill"  , "red");
-            bubble.setAttributeNS(null,"r"     , data[2]);
-            bubble.setAttributeNS(null,"cx"    , data[0]);
-            bubble.setAttributeNS(null,"cy"    , data[1]);
-            svgElem.appendChild(bubble);
-        });
-    }
-    "#;
-
-    let fn_set_size = r#"{
-        const root    = arguments[0];
-        const width   = arguments[1][0];
-        const height  = arguments[1][1];
-        const svgElem = root.firstChild;
-        svgElem.setAttributeNS(null, "viewBox", "0 0 " + width + " " + height);
-        svgElem.setAttributeNS(null, "width"  , width);
-        svgElem.setAttributeNS(null, "height" , height);
-    }"#;
-    JsRenderer::from_functions(fn_set_data, fn_set_size)
-}
-
-/// Returns a simple bubble chart implemented in vanilla JS. Uses an object to implement the
-/// visualization logic.
-pub fn object_sample_js_bubble_chart() -> JsRenderer {
-    let fn_prototype = r#"
-    (() => {
-        class BubbleVisualisation {
-            onDataReceived(root, data) {
-                const xmlns = "http://www.w3.org/2000/svg";
-                while (root.firstChild) {
-                    root.removeChild(root.lastChild);
-                }
-
-                const svgElem = document.createElementNS(xmlns, "svg");
-                svgElem.setAttributeNS(null, "id"     , "vis-svg");
-                svgElem.setAttributeNS(null, "viewBox", "0 0 " + 100 + " " + 100);
-                svgElem.setAttributeNS(null, "width"  , 100);
-                svgElem.setAttributeNS(null, "height" , 100);
-                root.appendChild(svgElem);
-
-                data.forEach(data => {
-                    const bubble = document.createElementNS(xmlns,"circle");
-                    bubble.setAttributeNS(null,"stroke", "black");
-                    bubble.setAttributeNS(null,"fill"  , "red");
-                    bubble.setAttributeNS(null,"r"     , data[2]);
-                    bubble.setAttributeNS(null,"cx"    , data[0]);
-                    bubble.setAttributeNS(null,"cy"    , data[1]);
-                    svgElem.appendChild(bubble);
-                });
-            }
-
-            setSize(root, size) {
-                const width   = size[0];
-                const height  = size[1];
-                const svgElem = root.firstChild;
-                svgElem.setAttributeNS(null, "viewBox", "0 0 " + width + " " + height);
-                svgElem.setAttributeNS(null, "width"  , width);
-                svgElem.setAttributeNS(null, "height" , height);
-            }
-        }
-
-        return new BubbleVisualisation();
-    })()
-    "#;
-    JsRenderer::from_object(fn_prototype).unwrap()
-}
-
-
-
-/// Returns a simple bubble chart implemented in vanilla JS. uses single functions to implement the
-/// visualization.
-pub fn constructor_sample_js_bubble_chart() -> JsRenderer {
+/// Return an `JsSourceClass` that creates example Bubble Visualizations implemented in JS.
+pub fn get_bubble_vis_class() -> JsSourceClass {
     let fn_constructor = r#"
-        class BubbleVisualisation {
+        class BubbleVisualization {
+            static inputTypes = ["[[Float,Float,Float]]"]
+
             onDataReceived(root, data) {
                 const xmlns = "http://www.w3.org/2000/svg";
                 while (root.firstChild) {
@@ -133,7 +44,8 @@ pub fn constructor_sample_js_bubble_chart() -> JsRenderer {
             }
         }
 
-        return new BubbleVisualisation();
+        return BubbleVisualization;
     "#;
-    JsRenderer::from_constructor(fn_constructor).unwrap()
+
+    JsSourceClass::from_js_source_raw(fn_constructor).unwrap()
 }

gui/src/rust/lib/graph-editor/src/component/visualization/renderer/example/native.rs

@@ -1,4 +1,4 @@
-//! Examples of defining visualisation in Rust using web_sys or ensogl.
+//! Examples of defining visualization in Rust using web_sys or ensogl.
 
 use crate::prelude::*;
 

gui/src/rust/lib/graph-editor/src/component/visualization/renderer/js.rs

@@ -1,7 +1,7 @@
 //! This module contains functionality that allows the usage of JavaScript to define visualizations.
 //!
 //! The `JsRenderer` defines a generic way to wrap JS function calls and allow interaction with
-//! JS code and the visualisation system.
+//! JS code and the visualization system.
 //!
 //! There are at the moment three way to generate a `JsRenderer`:
 //! 1. `JsRenderer::from_functions` where the bodies of the required functions are provided as
@@ -11,12 +11,15 @@
 //! 3. `JsRenderer::from_constructor`where the body of a constructor function needs to be
 //!     provided. The returned object needs to fulfill the same specification as in (2).
 //!
-//! Right now the only functions required on the wrapped object are
-//!  * `onDataReceived(root, data)`, which receives the html element that the visualisation should be
+//! Right now the only functions supported on the wrapped object are
+//!  * `onDataReceived(root, data)`, which receives the html element that the visualization should be
 //!     appended on, as well as the data that should be rendered.
-//!  * `setSize(root, size)`, which receives the node that the visualisation should be appended on,
+//!  * `setSize(root, size)`, which receives the node that the visualization should be appended on,
 //!    as well as the intended size.
 //!
+//! All functions on the class are optional, and methods that are not present, will be handled as
+//! no-op by the  `JsRenderer`.
+//!
 //! TODO: refine spec and add functions as needed, e.g., init, callback hooks or type indicators.
 
 use crate::prelude::*;
@@ -32,6 +35,7 @@ use ensogl::display;
 use ensogl::system::web::JsValue;
 use ensogl::system::web;
 use js_sys;
+use std::fmt::Formatter;
 
 
 
@@ -42,27 +46,49 @@ use js_sys;
 /// Errors that can occur when transforming JS source to a visualization.
 #[derive(Clone,Debug)]
 #[allow(missing_docs)]
-pub enum JsVisualisationError {
+pub enum JsVisualizationError {
     NotAnObject  { inner:JsValue },
     NotAFunction { inner:JsValue },
-    /// An unknown error occurred on the JS side. Inspect the content for more information. .
+    /// An unknown error occurred on the JS side. Inspect the content for more information.
     Unknown      { inner:JsValue }
 }
 
-impl From<JsValue> for JsVisualisationError {
-    fn from(value:JsValue) -> Self {
-        // TODO add differentiation if we encounter specific errors and return new variants.
-        JsVisualisationError::Unknown {inner:value}
+impl Display for JsVisualizationError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        // TODO find a nice way to circumvent the fact that `JsValue` does not implement `Display`.
+        match self {
+            JsVisualizationError::NotAnObject { inner }  => {
+                f.write_fmt(format_args!("Not an object: {:?}",inner))
+            },
+            JsVisualizationError::NotAFunction { inner } => {
+                f.write_fmt(format_args!("Not a function: {:?}",inner))
+            },
+            JsVisualizationError::Unknown { inner }      => {
+                f.write_fmt(format_args!("Unknown: {:?}",inner))
+            },
+        }
     }
 }
 
+impl std::error::Error for JsVisualizationError {}
+
+impl From<JsValue> for JsVisualizationError {
+    fn from(value:JsValue) -> Self {
+        // TODO add differentiation if we encounter specific errors and return new variants.
+        JsVisualizationError::Unknown {inner:value}
+    }
+}
+
+/// Internal helper type to propagate results that can fail due to `JsVisualizationError`s.
+pub(crate) type JsResult<T> = Result<T, JsVisualizationError>;
+
 
 
 // ==================
 // === JsRenderer ===
 // ==================
 
-/// `JsVisualizationGeneric` allows the use of arbitrary javascript to create visualisations. It
+/// `JsVisualizationGeneric` allows the use of arbitrary javascript to create visualizations. It
 /// takes function definitions as strings and proved those functions with data.
 #[derive(Clone,Debug)]
 #[allow(missing_docs)]
@@ -81,11 +107,11 @@ impl JsRenderer {
     /// code will be executed as the function body of the respective functions.
     ///
     /// `fn_set_data` will be called with two arguments: the first argument (`root) )will be the
-    /// root node that the visualisation should use to build its output, the second argument
+    /// root node that the visualization should use to build its output, the second argument
     /// (`data`)will be the data that it should visualise.
     ///
     /// `fn_set_size` will be called with a tuple of floating point values indicating the desired
-    /// width and height. This can be used by the visualisation to ensure proper scaling.
+    /// width and height. This can be used by the visualization to ensure proper scaling.
     ///
     /// For a full example see
     /// `crate::component::visualization::renderer::example::function_sample_js_bubble_chart`
@@ -103,21 +129,21 @@ impl JsRenderer {
     }
 
     /// Internal helper that tries to convert a JS object into a `JsRenderer`.
-    fn from_object_js(object:js_sys::Object) -> Result<JsRenderer,JsVisualisationError> {
+    fn from_object_js(object:js_sys::Object) -> Result<JsRenderer,JsVisualizationError> {
         let set_data = js_sys::Reflect::get(&object,&"onDataReceived".into())?;
         let set_size = js_sys::Reflect::get(&object,&"setSize".into())?;
         if !set_data.is_function() {
-            return Err(JsVisualisationError::NotAFunction { inner:set_data })
+            return Err(JsVisualizationError::NotAFunction { inner:set_data })
         }
         if !set_size.is_function() {
-            return Err(JsVisualisationError::NotAFunction { inner:set_size })
+            return Err(JsVisualizationError::NotAFunction { inner:set_size })
         }
         let set_data:js_sys::Function = set_data.into();
         let set_size:js_sys::Function = set_size.into();
 
-        let logger  = Logger::new("JsRenderer");
-        let frp     = default();
-        let div     = web::create_div();
+        let logger    = Logger::new("JsRenderer");
+        let frp       = default();
+        let div       = web::create_div();
         let root_node = DomSymbol::new(&div);
         root_node.dom().set_attribute("id","vis")?;
 
@@ -132,22 +158,30 @@ impl JsRenderer {
     /// ```no_run
     /// use graph_editor::component::visualization::JsRenderer;
     ///
-    /// let renderer = JsRenderer::from_object("function() {
+    /// let renderer = JsRenderer::from_object_source(r#"function() {
     ///   class Visualization {
+    ///       static inputTypes = ["[[Float,Float,Float]]"]
     ///       onDataReceived(root, data) {};
     ///       setSize(root, size) {};
     ///   }
-    ///   return new Visualisation();
-    /// }()").unwrap();
+    ///   return Visualization;
+    /// }()"#).unwrap();
     ///
     /// ```
     ///
     /// For a full example see
     /// `crate::component::visualization::renderer::example::object_sample_js_bubble_chart`
-    pub fn from_object(source: &str) -> Result<JsRenderer,JsVisualisationError> {
+    pub fn from_object_source(source: &str) -> Result<JsRenderer,JsVisualizationError> {
         let object = js_sys::eval(source)?;
         if !object.is_object() {
-            return Err(JsVisualisationError::NotAnObject { inner:object } )
+            return Err(JsVisualizationError::NotAnObject { inner:object } )
+        }
+        Self::from_object_js(object.into())
+    }
+
+    pub(crate) fn from_object(object:JsValue) -> Result<JsRenderer,JsVisualizationError> {
+        if !object.is_object() {
+            return Err(JsVisualizationError::NotAnObject { inner:object } )
         }
         Self::from_object_js(object.into())
     }
@@ -165,26 +199,25 @@ impl JsRenderer {
     ///       onDataReceived(root, data) {};
     ///       setSize(root, size) {};
     ///   }
-    ///   return new Visualisation();
+    ///   return Visualization;
     ///   ").unwrap();
     ///
     /// ```
     /// For a full example see
     /// `crate::component::visualization::renderer::example::constructor_sample_js_bubble_chart`
-    pub fn from_constructor(source:&str) -> Result<JsRenderer,JsVisualisationError> {
+    pub fn from_constructor(source:&str) -> Result<JsRenderer,JsVisualizationError> {
         let context     = JsValue::NULL;
         let constructor = js_sys::Function::new_no_args(source);
         let object      = constructor.call0(&context)?;
         if !object.is_object() {
-            return Err(JsVisualisationError::NotAnObject { inner:object } )
+            return Err(JsVisualizationError::NotAnObject { inner:object } )
         }
         Self::from_object_js(object.into())
     }
 
     /// Hooks the root node into the given scene.
     ///
-    /// MUST be called to make this visualisation visible.
-    // TODO[mm] find a better mechanism to ensure this. Probably through the registry later on.
+    /// MUST be called to make this visualization visible.
     pub fn set_dom_layer(&self, scene:&DomScene) {
         scene.manage(&self.root_node);
     }

gui/src/rust/lib/graph-editor/src/lib.rs

@@ -56,9 +56,7 @@ use nalgebra::Vector2;
 use ensogl::display::Scene;
 use crate::component::visualization::Visualization;
 use crate::component::visualization;
-use crate::component::visualization::example::js::constructor_sample_js_bubble_chart;
 use crate::component::visualization::MockDataGenerator3D;
-use crate::component::visualization::example::native;
 
 
 
@@ -247,7 +245,7 @@ ensogl::def_command_api! { Commands
     remove_selected_nodes,
     /// Remove all nodes from the graph.
     remove_all_nodes,
-    /// Toggle the visibility of the selected visualisations
+    /// Toggle the visibility of the selected visualizations
     toggle_visualization_visibility,
 
 
@@ -288,7 +286,7 @@ ensogl::def_command_api! { Commands
     debug_set_data_for_selected_node,
 
     /// Cycle the visualization for the selected nodes. TODO only has dummy functionality at the moment.
-    debug_cycle_visualisation_for_selected_node,
+    debug_cycle_visualization_for_selected_node,
 }
 
 impl Commands {
@@ -318,7 +316,7 @@ impl Commands {
             def toggle_node_inverse_select       = source();
 
             def debug_set_data_for_selected_node            = source();
-            def debug_cycle_visualisation_for_selected_node = source();
+            def debug_cycle_visualization_for_selected_node = source();
 
         }
         Self {add_node,add_node_at_cursor,remove_selected_nodes,remove_all_nodes
@@ -327,7 +325,7 @@ impl Commands {
              ,enable_node_merge_select,disable_node_merge_select,toggle_node_merge_select
              ,enable_node_subtract_select,disable_node_subtract_select,toggle_node_subtract_select
              ,enable_node_inverse_select,disable_node_inverse_select,toggle_node_inverse_select
-             ,debug_set_data_for_selected_node,debug_cycle_visualisation_for_selected_node}
+             ,debug_set_data_for_selected_node,debug_cycle_visualization_for_selected_node}
     }
 }
 
@@ -358,6 +356,7 @@ pub struct FrpInputs {
     pub translate_selected_nodes       : frp::Source<Position>,
     pub cycle_visualization            : frp::Source<NodeId>,
     pub set_visualization              : frp::Source<(NodeId,Option<Visualization>)>,
+    pub register_visualization_class   : frp::Source<Option<Rc<visualization::Handle>>>,
 }
 
 impl FrpInputs {
@@ -380,13 +379,16 @@ impl FrpInputs {
             def translate_selected_nodes       = source();
             def cycle_visualization            = source();
             def set_visualization              = source();
+            def register_visualization_class   = source();
         }
         let commands = Commands::new(&network);
         Self {commands,remove_edge,press_node_input,remove_all_node_edges
              ,remove_all_node_input_edges,remove_all_node_output_edges,set_visualization_data
              ,connect_detached_edges_to_node,connect_edge_source,connect_edge_target
              ,set_node_position,select_node,translate_selected_nodes,set_node_expression
-             ,connect_nodes,deselect_all_nodes,cycle_visualization,set_visualization}
+             ,connect_nodes,deselect_all_nodes,cycle_visualization,set_visualization
+             ,register_visualization_class
+        }
     }
 }
 
@@ -789,17 +791,8 @@ impl GraphEditorModelWithNetwork {
             ));
         }
 
-        let chart = constructor_sample_js_bubble_chart();
-        let dom_layer    = model.scene.dom.layers.front.clone_ref();
-        chart.set_dom_layer(&dom_layer);
-
-        let vis = Visualization::new(chart);
-        node.view.frp.set_visualization.emit(Some(vis));
-
-
         self.nodes.insert(node_id,node);
 
-
         node_id
     }
 
@@ -1132,7 +1125,7 @@ impl application::shortcut::DefaultShortcutProvider for GraphEditor {
              , Self::self_shortcut(shortcut::Action::press   (&[Key::Shift,Key::Alt])        , "toggle_node_inverse_select")
              , Self::self_shortcut(shortcut::Action::release (&[Key::Shift,Key::Alt])        , "toggle_node_inverse_select")
              , Self::self_shortcut(shortcut::Action::press   (&[Key::Character("d".into())]) , "debug_set_data_for_selected_node")
-             , Self::self_shortcut(shortcut::Action::press   (&[Key::Character("f".into())]) , "debug_cycle_visualisation_for_selected_node")
+             , Self::self_shortcut(shortcut::Action::press   (&[Key::Character("f".into())]) , "debug_cycle_visualization_for_selected_node")
         ]
     }
 }
@@ -1201,13 +1194,16 @@ fn new_graph_editor(world:&World) -> GraphEditor {
     web::body().set_style_or_panic("cursor","none");
     world.add_child(&cursor);
 
-    let model   = GraphEditorModelWithNetwork::new(scene,cursor.clone_ref());
-    let network = &model.network;
-    let nodes   = &model.nodes;
-    let edges   = &model.edges;
-    let inputs  = &model.frp;
-    let mouse   = &scene.mouse.frp;
-    let touch   = &model.touch_state;
+    let model                  = GraphEditorModelWithNetwork::new(scene,cursor.clone_ref());
+    let network                = &model.network;
+    let nodes                  = &model.nodes;
+    let edges                  = &model.edges;
+    let inputs                 = &model.frp;
+    let mouse                  = &scene.mouse.frp;
+    let touch                  = &model.touch_state;
+    let visualization_registry = visualization::Registry::with_default_visualizations();
+    let logger                 = &model.logger;
+
 
     let outputs = UnsealedFrpOutputs::new();
     let sealed_outputs = outputs.seal(); // Done here to keep right eval order.
@@ -1414,12 +1410,8 @@ fn new_graph_editor(world:&World) -> GraphEditor {
         })
     }));
 
-
-
-
-    // === Vis Cycling ===
-
-    def _cycle_vis= inputs.debug_cycle_visualisation_for_selected_node.map(f!([inputs,nodes](_) {
+     // === Vis Cycling ===
+     def _cycle_vis = inputs.debug_cycle_visualization_for_selected_node.map(f!([inputs,nodes](_) {
         nodes.selected.for_each(|node| inputs.cycle_visualization.emit(node));
     }));
 
@@ -1432,8 +1424,9 @@ fn new_graph_editor(world:&World) -> GraphEditor {
         }
     }));
 
+    // === Vis Update Data ===
+
     // TODO remove this once real data is available.
-    let dummy_switch  = Rc::new(Cell::new(false));
     let sample_data_generator = MockDataGenerator3D::default();
     def _set_dumy_data = inputs.debug_set_data_for_selected_node.map(f!([nodes](_) {
         nodes.selected.for_each(|node_id| {
@@ -1446,21 +1439,21 @@ fn new_graph_editor(world:&World) -> GraphEditor {
         })
     }));
 
-     def _set_dumy_data = inputs.cycle_visualization.map(f!([scene,nodes](node_id) {
-        // TODO remove dummy cycling once we have the visualization registry.
-        let dc = dummy_switch.get();
-        dummy_switch.set(!dc);
-        let vis = if dc {
-            Visualization::new(native::BubbleChart::new(&scene))
-        } else {
-            let chart     = constructor_sample_js_bubble_chart();
-            let dom_layer = scene.dom.layers.front.clone_ref();
-            chart.set_dom_layer(&dom_layer);
-            Visualization::new(chart)
+     let cycle_count = Rc::new(Cell::new(0));
+     def _cycle_visualization = inputs.cycle_visualization.map(f!([scene,nodes,visualization_registry,logger](node_id) {
+        let visualizations = visualization_registry.valid_sources(&"[[Float,Float,Float]]".into());
+        cycle_count.set(cycle_count.get() % visualizations.len());
+        let vis  = &visualizations[cycle_count.get()];
+        let vis  = vis.instantiate(&scene);
+        let node = nodes.get_cloned_ref(node_id);
+        match (vis, node) {
+            (Ok(vis), Some(node))  => {
+                    node.view.visualization_container.frp.set_visualization.emit(Some(vis));
+            },
+            (Err(e), _) =>  logger.warning(|| format!("Failed to cycle visualization: {}", e)),
+            _           => {}
         };
-        if let Some(node) = nodes.get_cloned_ref(node_id) {
-            node.view.visualization_container.frp.set_visualization.emit(Some(vis));
-        }
+        cycle_count.set(cycle_count.get() + 1);
     }));
 
     def _toggle_selected = inputs.toggle_visualization_visibility.map(f!([nodes](_) {
@@ -1469,8 +1462,16 @@ fn new_graph_editor(world:&World) -> GraphEditor {
                 node.view.visualization_container.frp.toggle_visibility.emit(());
             }
         });
+
     }));
 
+    // === Register Visualization ===
+
+    def _register_visualization = inputs.register_visualization_class.map(f!([visualization_registry](handle) {
+        if let Some(handle) = handle {
+            visualization_registry.register_class_from_handle(&handle);
+        }
+    }));
 
 
     // === OUTPUTS REBIND ===