wallet: add stubs for plugin subsystem

bin/darkwallet/src/main.rs

@@ -18,6 +18,8 @@ use net::ZeroMQAdapter;
 mod scene;
 use scene::{SceneGraph, SceneGraphPtr};
 
+mod plugin;
+
 mod prop;
 
 mod shader;
@@ -35,9 +37,19 @@ fn start_zmq(scene_graph: SceneGraphPtr) {
     });
 }
 
+fn start_sentinel(scene_graph: SceneGraphPtr) {
+    // detach thread
+    // Sentinel should cleanly close when sent a stop signal.
+    let _ = thread::spawn(move || {
+        let mut sentinel = plugin::Sentinel::new(scene_graph);
+        sentinel.run();
+    });
+}
+
 fn main() {
     let scene_graph = Arc::new(Mutex::new(SceneGraph::new()));
     start_zmq(scene_graph.clone());
+    start_sentinel(scene_graph.clone());
     run_gui(scene_graph);
 }
 

bin/darkwallet/src/plugin.rs

@@ -0,0 +1,94 @@
+use crate::{
+    error::{Error, Result},
+scene::{SceneGraph, SceneGraphPtr}
+};
+
+enum Category {
+    Null,
+}
+
+enum SubCategory {
+    Null,
+}
+
+struct SemVer {
+    pub major: u64,
+    pub minor: u64,
+    pub patch: u64,
+    pub pre: String,
+    pub build: String,
+}
+
+struct PluginMetadata {
+    pub name: String,
+    pub title: String,
+    pub desc: String,
+    pub author: String,
+    pub version: SemVer,
+
+    pub cat: Category,
+    pub subcat: SubCategory,
+
+    // icon
+
+    // Permissions
+    // whitelisted nodes + props/methods (use * for all)
+    // /window/input/*
+}
+
+enum PluginEvent {
+    // (signal_data, user_data)
+    RecvSignal((Vec<u8>, Vec<u8>)),
+}
+
+trait Plugin {
+    fn metadata(&self) -> PluginMetadata;
+    fn init(&mut self) -> Result<()>;
+    fn update(&mut self, event: PluginEvent) -> Result<()>;
+}
+
+type InstanceId = u32;
+
+pub struct Sentinel {
+ scene_graph: SceneGraphPtr
+}
+
+impl Sentinel {
+    pub fn new(scene_graph: SceneGraphPtr) -> Self {
+        // Create /plugin in scene graph
+        //
+        // Methods provided in SceneGraph under /plugin:
+        //
+        // * import_plugin(pycode)
+
+        Self {
+            scene_graph
+        }
+    }
+
+    pub fn run(&mut self) {
+        // loop {
+            // Monitor all running plugins
+            // Check last update times
+            // Kill any slowpokes
+
+            // Check any SceneGraph method requests
+        // }
+    }
+
+    fn import_plugin(&mut self, plugin: Box<dyn Plugin>) -> Result<()> {
+        // Create /plugin/foo
+        // Add a method called start()
+        Ok(())
+    }
+
+    fn start_plugin(&mut self, plugin_name: &str) -> Result<InstanceId> {
+        // Lookup plugin by name
+        // Call init()
+        // Spawn a new thread, allocate it an ID
+        // Thread waits for events from the scene_graph and calls update() when they occur.
+        // See src/net.rs:81 for an example
+        Ok(0)
+    }
+}
+