Complete proof of concept

2022-09-11 23:45:31 -04:00 · 2022-09-11 23:45:31 -04:00 · 569eab5880
commit 569eab5880
parent 0435f14680
46 changed files with 1413 additions and 169 deletions
--- a/.gitignore
+++ b/.gitignore
@ -42,8 +42,8 @@ yalc.lock
 .vscode/settings.json

 # ignore Rust compiler files
-/server/target
-backend
+/backend/target
+/backend/out
 /bin

 # packaged teasers
--- a/backend/Cargo.lock
+++ b/backend/Cargo.lock
@ -2,6 +2,28 @@
 # It is not intended for manual editing.
 version = 3

+[[package]]
+name = "async-recursion"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2cda8f4bcc10624c4e85bc66b3f452cca98cfa5ca002dc83a16aad2367641bea"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "async-trait"
+version = "0.1.57"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76464446b8bc32758d7e88ee1a804d9914cd9b1cb264c029899680b0be29826f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@ -349,10 +371,12 @@ checksum = "112c678d4050afce233f4f2852bb2eb519230b3cf12f33585275537d7e41578d"
 name = "kaylon"
 version = "0.1.0"
 dependencies = [
+ "async-trait",
 "log",
 "serde",
 "serde_json",
 "simplelog",
+ "tokio",
 "usdpl-back",
 ]

@ -959,11 +983,12 @@ dependencies = [

 [[package]]
 name = "usdpl-back"
-version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbbc0781e83ba990f8239142e33173a2d2548701775f3db66702d1af4fd0319a"
+version = "0.7.0"
 dependencies = [
+ "async-recursion",
+ "async-trait",
 "bytes",
+ "log",
 "tokio",
 "usdpl-core",
 "warp",
@ -972,8 +997,6 @@ dependencies = [
 [[package]]
 name = "usdpl-core"
 version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "862153581fac266458521f49e5906a71c1eee1665cb4c7d71e9586bd34b45394"
 dependencies = [
 "base64",
 ]
--- a/backend/Cargo.toml
+++ b/backend/Cargo.toml
@ -6,8 +6,13 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-usdpl-back = { version = "0.6.0", features = ["decky"] }
+usdpl-back = { version = "0.7.0", features = ["decky"], path = "../../usdpl-rs/usdpl-back" }

+# async
+tokio = { version = "*", features = ["sync", "time"] }
+async-trait = "0.1.57"
+
+# json
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"

--- a/backend/Cross.toml
+++ b/backend/Cross.toml
--- a/backend/build.sh
+++ b/backend/build.sh
@ -0,0 +1,12 @@
+#!/bin/bash
+
+#cargo build --release --target x86_64-unknown-linux-musl
+cargo build --target x86_64-unknown-linux-musl
+#cross build --release
+
+mkdir -p ../bin
+#cp ./target/x86_64-unknown-linux-musl/release/kaylon ../bin/backend
+cp ./target/x86_64-unknown-linux-musl/debug/kaylon ../bin/backend
+#cp ./target/release/kaylon ../bin/backend
+
+cp ../kaylon.json ../bin/kaylon.json
--- a/backend/src/api/about.rs
+++ b/backend/src/api/about.rs
@ -0,0 +1,25 @@
+use std::sync::{Mutex, mpsc::{Sender, channel}};
+
+use super::ApiParameterType;
+
+use crate::runtime::{QueueAction, QueueItem};
+
+pub fn get_about(sender: Sender<QueueItem>) -> impl Fn(ApiParameterType) -> ApiParameterType {
+    let sender = Mutex::new(sender);
+    move |_| {
+        log::debug!("API: get_about");
+        let (rx, tx) = channel();
+        sender.lock().unwrap().send(
+            QueueItem {
+                action: QueueAction::GetAbout {
+                    respond_to: rx,
+                }
+            }
+        ).unwrap();
+        vec![
+            usdpl_back::core::serdes::Primitive::Json(
+                serde_json::to_string(&tx.recv().unwrap()).unwrap()
+            )
+        ]
+    }
+}
--- a/backend/src/api/get_display.rs
+++ b/backend/src/api/get_display.rs
@ -0,0 +1,72 @@
+use std::sync::{Mutex, mpsc::{Sender, channel, self}};
+
+use usdpl_back::core::serdes::Primitive;
+use usdpl_back::AsyncCallable;
+
+use super::ApiParameterType;
+
+use crate::runtime::{QueueAction, QueueItem};
+
+pub struct GetDisplayEndpoint {
+    //sender: tokio::sync::mpsc::Sender<SetCallbackAsync>,
+    //receiver: Mutex<Option<tokio::sync::mpsc::Receiver<SetCallbackAsync>>>,
+    sync_sender: Mutex<Sender<QueueItem>>,
+}
+
+impl GetDisplayEndpoint {
+    pub fn new(sender: Sender<QueueItem>) -> Self {
+        //let (async_tx, async_rx) = tokio::sync::mpsc::channel::<SetCallbackAsync>(64);
+        Self {
+            //sender: async_tx,
+            //receiver: Mutex::new(Some(async_rx)),
+            sync_sender: Mutex::new(sender),
+        }
+    }
+}
+
+#[async_trait::async_trait]
+impl AsyncCallable for GetDisplayEndpoint {
+    async fn call(&self, params: ApiParameterType) -> ApiParameterType {
+        log::debug!("API: get_display");
+        if let Some(Primitive::F64(index)) = params.get(0) {
+            let index = *index as usize;
+            let (respond_to, receiver) = channel();
+            log::info!("requesting display for item #{}", index);
+            let send_result = self.sync_sender.lock().unwrap().send(
+                QueueItem {
+                    action: QueueAction::SetCallback {
+                        index,
+                        respond_to,
+                    }
+                }
+            );
+            if let Ok(_) = send_result {
+                // TODO: don't poll for response
+                log::info!("waiting for display for item #{}", index);
+                let sleep_duration = std::time::Duration::from_millis(10);
+                let receiver = Mutex::new(receiver);
+                loop {
+                    let received = receiver.lock().unwrap().try_recv();
+                    match received {
+                        Err(mpsc::TryRecvError::Disconnected) => {
+                            log::info!("Failed to response for get_display for #{}", index);
+                            return vec![Primitive::Empty];
+                        },
+                        Err(_) => {},
+                        Ok(x) => {
+                            log::debug!("got display for item #{}", index);
+                            return vec![x];
+                        },
+                    }
+                    tokio::time::sleep(sleep_duration).await;
+                }
+            } else {
+                log::info!("Failed to get_display for #{}", index);
+                vec![Primitive::Empty]
+            }
+
+        } else {
+            vec![Primitive::Empty]
+        }
+    }
+}
--- a/backend/src/api/get_item.rs
+++ b/backend/src/api/get_item.rs
@ -0,0 +1,26 @@
+use std::sync::{Mutex, mpsc::{Sender, channel}};
+
+use super::ApiParameterType;
+
+use crate::runtime::{QueueAction, QueueItem};
+
+pub fn get_items(sender: Sender<QueueItem>) -> impl Fn(ApiParameterType) -> ApiParameterType {
+    let sender = Mutex::new(sender);
+    move |_| {
+        log::debug!("API: get_items");
+        let (rx, tx) = channel();
+        sender.lock().unwrap().send(
+            QueueItem {
+                action: QueueAction::DoReload {
+                    respond_to: rx,
+                }
+            }
+        ).unwrap();
+        log::info!("waiting for items");
+        vec![
+            usdpl_back::core::serdes::Primitive::Json(
+                serde_json::to_string(&tx.recv().unwrap()).unwrap()
+            )
+        ]
+    }
+}
--- a/backend/src/api/mod.rs
+++ b/backend/src/api/mod.rs
@ -0,0 +1,13 @@
+mod about;
+mod get_display;
+mod get_item;
+mod on_update;
+mod reload;
+
+pub use about::get_about;
+pub use get_display::GetDisplayEndpoint;
+pub use get_item::get_items;
+pub use on_update::on_update;
+pub use reload::reload;
+
+pub(super) type ApiParameterType = Vec<usdpl_back::core::serdes::Primitive>;
--- a/backend/src/api/on_update.rs
+++ b/backend/src/api/on_update.rs
@ -0,0 +1,34 @@
+use std::sync::{Mutex, mpsc::Sender};
+
+use usdpl_back::core::serdes::Primitive;
+
+use super::ApiParameterType;
+
+use crate::runtime::{QueueAction, QueueItem};
+
+pub fn on_update(sender: Sender<QueueItem>) -> impl Fn(ApiParameterType) -> ApiParameterType {
+    let sender = Mutex::new(sender);
+    move |mut params: ApiParameterType| {
+        log::debug!("API: on_update");
+        if params.len() == 2 {
+            if let Primitive::F64(index) = params.remove(0) {
+                let index = index as usize;
+                let val = params.remove(0);
+                sender.lock().unwrap().send(
+                    QueueItem {
+                        action: QueueAction::DoUpdate {
+                            index,
+                            value: val,
+                        }
+                    }
+                ).unwrap();
+                log::info!("Sent update for #{}", index);
+                vec![true.into()]
+            } else {
+                vec![false.into()]
+            }
+        } else {
+            vec![false.into()]
+        }
+    }
+}
--- a/backend/src/api/reload.rs
+++ b/backend/src/api/reload.rs
@ -0,0 +1,26 @@
+use std::sync::{Mutex, mpsc::{Sender, channel}};
+
+use super::ApiParameterType;
+
+use crate::runtime::{QueueAction, QueueItem};
+
+pub fn reload(sender: Sender<QueueItem>) -> impl Fn(ApiParameterType) -> ApiParameterType {
+    let sender = Mutex::new(sender);
+    move |_| {
+        log::debug!("API: reload");
+        let (rx, tx) = channel();
+        sender.lock().unwrap().send(
+            QueueItem {
+                action: QueueAction::DoReload {
+                    respond_to: rx,
+                }
+            }
+        ).unwrap();
+        log::info!("waiting for JSON reload");
+        vec![
+            usdpl_back::core::serdes::Primitive::Json(
+                serde_json::to_string(&tx.recv().unwrap()).unwrap()
+            )
+        ]
+    }
+}
--- a/backend/src/config/about.rs
+++ b/backend/src/config/about.rs
@ -0,0 +1,24 @@
+use serde::{Serialize, Deserialize};
+
+#[derive(Serialize, Deserialize, Clone)]
+pub struct AboutConfig {
+    pub name: String,
+    pub version: String,
+    pub description: String,
+    pub url: Option<String>,
+    pub authors: Vec<String>,
+    pub license: Option<String>,
+}
+
+impl Default for AboutConfig {
+    fn default() -> Self {
+        Self {
+            name: env!("CARGO_PKG_NAME").to_owned(),
+            version: env!("CARGO_PKG_VERSION").to_owned(),
+            description: env!("CARGO_PKG_DESCRIPTION").to_owned(),
+            url: Some(env!("CARGO_PKG_HOMEPAGE").to_owned()),
+            authors: env!("CARGO_PKG_AUTHORS").split(':').map(|x| x.to_owned()).collect(),
+            license: Some(env!("CARGO_PKG_LICENSE").to_owned())
+        }
+    }
+}
--- a/backend/src/config/action.rs
+++ b/backend/src/config/action.rs
--- a/backend/src/config/base.rs
+++ b/backend/src/config/base.rs
@ -0,0 +1,52 @@
+use serde::{Serialize, Deserialize};
+
+use super::{ElementConfig, AboutConfig};
+
+#[derive(Serialize, Deserialize, Clone)]
+#[serde(tag = "api-version")]
+pub enum BaseConfig {
+    #[serde(rename = "v0.0.0")]
+    V0 {
+        items: Vec<ElementConfig>,
+        about: AboutConfig,
+    },
+}
+
+impl BaseConfig {
+    pub fn load<P: AsRef<std::path::Path>>(path: P) -> Self {
+        //let path = std::path::Path::new("./").join(path);
+        let path = path.as_ref();
+        match std::fs::File::open(&path) {
+            Ok(file) => {
+                let reader = std::io::BufReader::new(file);
+                match serde_json::from_reader(reader) {
+                    Ok(conf) => return conf,
+                    Err(e) => log::error!("Failed to deserialize {}: {}", path.display(), e),
+                }
+            },
+            Err(e) => log::error!("Failed to open {}: {}", path.display(), e),
+        }
+        panic!("Cannot open {}", path.display())
+    }
+
+    #[inline]
+    pub fn get_about(&self) -> &AboutConfig {
+        match self {
+            Self::V0 {about, ..} => about,
+        }
+    }
+
+    #[inline]
+    pub fn get_item(&self, index: usize) -> Option<&ElementConfig> {
+        match self {
+            Self::V0 {items, ..} => items.get(index),
+        }
+    }
+
+    #[inline]
+    pub fn items(&self) -> &Vec<ElementConfig> {
+        match self {
+            Self::V0 {items, ..} => items,
+        }
+    }
+}
--- a/backend/src/config/button.rs
+++ b/backend/src/config/button.rs
--- a/backend/src/config/element.rs
+++ b/backend/src/config/element.rs
@ -1,6 +1,6 @@
 use serde::{Serialize, Deserialize};

-use super::{ButtonConfig, ToggleConfig, SliderConfig, ReadingConfig};
+use super::{ButtonConfig, ToggleConfig, SliderConfig, ReadingConfig, ResultDisplayConfig};

 #[derive(Serialize, Deserialize, Clone)]
 #[serde(tag = "element")]
@ -12,5 +12,7 @@ pub enum ElementConfig {
    #[serde(rename = "slider")]
    Slider(SliderConfig),
    #[serde(rename = "reading")]
-    Reading(ReadingConfig),
+    ReadingDisplay(ReadingConfig),
+    #[serde(rename = "result-display")]
+    ResultDisplay(ResultDisplayConfig),
 }
--- a/backend/src/config/mod.rs
+++ b/backend/src/config/mod.rs
@ -4,6 +4,7 @@ mod base;
 mod button;
 mod element;
 mod reading;
+mod result_display;
 mod slider;
 mod toggle;

@ -13,6 +14,7 @@ pub use base::BaseConfig;
 pub use button::ButtonConfig;
 pub use element::ElementConfig;
 pub use reading::ReadingConfig;
+pub use result_display::ResultDisplayConfig;
 pub use slider::SliderConfig;
 pub use toggle::ToggleConfig;

@ -31,8 +33,7 @@ mod test {
                ElementConfig::Toggle(ToggleConfig {
                    title: "Test Toggle".into(),
                    description: Some("Toggle description".into()),
-                    on_enable: ActionConfig::Command(CommandAction{run: "echo 'hello toggle 1'".into()}),
-                    on_disable: ActionConfig::Command(CommandAction{run: "echo 'hello toggle 0'".into()}),
+                    on_toggle: ActionConfig::Command(CommandAction{run: "echo 'hello toggle $KAYLON_VALUE'".into()}),
                }),
                ElementConfig::Slider(SliderConfig {
                    title: "Test Slider".into(),
@ -41,18 +42,22 @@ mod test {
                    notches: None,
                    on_set: ActionConfig::Command(CommandAction{run: "echo 'hello slider'".into()}),
                }),
-                ElementConfig::Reading(ReadingConfig {
+                ElementConfig::ReadingDisplay(ReadingConfig {
                    title: "Test Reading".into(),
                    period_ms: 10000,
                    on_period: ActionConfig::Command(CommandAction{run: "echo 'hello reading'".into()})
                }),
+                ElementConfig::ResultDisplay(ResultDisplayConfig {
+                    title: "Test Reading".into(),
+                    result_of: 1,
+                }),
            ],
            about: AboutConfig {
                name: "Test name".into(),
                version: "v0.42.0".into(),
                description: "Test description".into(),
                url: Some("https://github.com/NGnius/kaylon".into()),
-                author: Some("NGnius <ngniusness@gmail.com>".into()),
+                authors: vec!["NGnius <ngniusness@gmail.com>".into()],
                license: Some("MIT".into()),
            },
        };
--- a/backend/src/config/reading.rs
+++ b/backend/src/config/reading.rs
--- a/backend/src/config/result_display.rs
+++ b/backend/src/config/result_display.rs
@ -0,0 +1,8 @@
+use serde::{Serialize, Deserialize};
+
+#[derive(Serialize, Deserialize, Clone)]
+pub struct ResultDisplayConfig {
+    pub title: String,
+    /// index of element who's action's result will be used
+    pub result_of: usize,
+}
--- a/backend/src/config/slider.rs
+++ b/backend/src/config/slider.rs
--- a/backend/src/config/toggle.rs
+++ b/backend/src/config/toggle.rs
@ -6,6 +6,5 @@ use super::ActionConfig;
 pub struct ToggleConfig {
    pub title: String,
    pub description: Option<String>,
-    pub on_enable: ActionConfig,
-    pub on_disable: ActionConfig,
+    pub on_toggle: ActionConfig,
 }
--- a/backend/src/consts.rs
+++ b/backend/src/consts.rs
@ -0,0 +1,6 @@
+pub const PORT: u16 = 25717;
+
+pub const PACKAGE_NAME: &'static str = env!("CARGO_PKG_NAME");
+pub const PACKAGE_VERSION: &'static str = env!("CARGO_PKG_VERSION");
+
+pub const FILEPATH: &'static str = "./bin/kaylon.json";
--- a/backend/src/main.rs
+++ b/backend/src/main.rs
@ -0,0 +1,34 @@
+mod api;
+mod config;
+mod consts;
+mod runtime;
+
+use simplelog::{WriteLogger, LevelFilter};
+
+use usdpl_back::Instance;
+use usdpl_back::core::serdes::Primitive;
+
+fn main() -> Result<(), ()> {
+    let log_filepath = format!("/tmp/{}.log", consts::PACKAGE_NAME);
+    WriteLogger::init(
+        #[cfg(debug_assertions)]{LevelFilter::Debug},
+        #[cfg(not(debug_assertions))]{LevelFilter::Info},
+        Default::default(),
+        std::fs::File::create(&log_filepath).unwrap()
+    ).unwrap();
+
+    let kaylon_conf = config::BaseConfig::load(consts::FILEPATH);
+    let (executor, sender) = runtime::RuntimeExecutor::new(kaylon_conf);
+
+    log::info!("Starting back-end ({} v{})", consts::PACKAGE_NAME, consts::PACKAGE_VERSION);
+    println!("Starting back-end ({} v{})", consts::PACKAGE_NAME, consts::PACKAGE_VERSION);
+    let instance = Instance::new(consts::PORT)
+        .register("hello", |_: Vec<Primitive>| vec![format!("Hello {}", consts::PACKAGE_NAME).into()])
+        .register_blocking("get_about", api::get_about(sender.clone()))
+        .register_async("get_display", api::GetDisplayEndpoint::new(sender.clone()))
+        .register_blocking("get_items", api::get_items(sender.clone()))
+        .register("on_update", api::on_update(sender.clone()))
+        .register_blocking("reload", api::reload(sender.clone()));
+    let _exec_handle = executor.spawn();
+    instance.run_blocking()
+}
--- a/backend/src/runtime/actor.rs
+++ b/backend/src/runtime/actor.rs
@ -0,0 +1,68 @@
+use usdpl_back::core::serdes::Primitive;
+
+use crate::config::{ElementConfig, ActionConfig};
+
+pub type ActError = String;
+
+pub trait Act: Sized {
+    type Param;
+    type Config: ?Sized;
+    type Return;
+    fn build(config: &Self::Config, parameter: Self::Param) -> Result<Self, ActError>;
+    fn run(self) -> Self::Return;
+}
+
+pub struct Actor {
+    actor_type: ActorType,
+    index: usize,
+}
+
+impl Act for Actor {
+    type Param = (usize, Primitive);
+    type Config = ElementConfig;
+    type Return = Primitive;
+
+    fn build(config: &ElementConfig, parameter: Self::Param) -> Result<Self, ActError> {
+        let a_type = match config {
+            ElementConfig::Button(b) => ActorType::build(&b.on_click, parameter.1),
+            ElementConfig::Toggle(t) => ActorType::build(&t.on_toggle, parameter.1),
+            ElementConfig::Slider(s) => ActorType::build(&s.on_set, parameter.1),
+            ElementConfig::ReadingDisplay(r) => ActorType::build(&r.on_period, parameter.1),
+            ElementConfig::ResultDisplay(_) => Err(format!("Item #{} is a ResultDisplay, which can't act", parameter.0)),
+        }?;
+        Ok(Self {
+            actor_type: a_type,
+            index: parameter.0,
+        })
+    }
+
+    fn run(self) -> Self::Return {
+        log::info!("Running act for item {}", self.index);
+        let result = self.actor_type.run();
+        log::info!("Completed act for item {}", self.index);
+        result
+    }
+}
+
+pub enum ActorType {
+    Command(super::CommandActor),
+}
+
+impl Act for ActorType {
+    type Param = Primitive;
+    type Config = ActionConfig;
+    type Return = Primitive;
+
+    fn build(config: &Self::Config, parameter: Self::Param) -> Result<Self, ActError> {
+        Ok(match config {
+            ActionConfig::Command(c) =>
+                Self::Command(super::CommandActor::build(c, parameter)?),
+        })
+    }
+
+    fn run(self) -> Self::Return {
+        match self {
+            Self::Command(c) => c.run().into(),
+        }
+    }
+}
--- a/backend/src/runtime/command_actor.rs
+++ b/backend/src/runtime/command_actor.rs
@ -0,0 +1,61 @@
+use std::process::Command;
+
+use usdpl_back::core::serdes::Primitive;
+
+use crate::config::CommandAction;
+use super::{Act, ActError};
+
+const VALUE_ENV_VAR: &str = "KAYLON_VALUE";
+
+pub struct CommandActor {
+    shell: String,
+    run: String,
+    variable: String,
+}
+
+impl CommandActor {
+    fn primitive_to_string(obj: Primitive) -> String {
+        match obj {
+            Primitive::Empty => String::new(),
+            Primitive::String(s) => s,
+            Primitive::F32(f) => f.to_string(),
+            Primitive::F64(f) => f.to_string(),
+            Primitive::I32(i) => i.to_string(),
+            Primitive::I64(i) => i.to_string(),
+            Primitive::U32(u) => u.to_string(),
+            Primitive::U64(u) => u.to_string(),
+            Primitive::Bool(b) => b.to_string().to_uppercase(),
+            Primitive::Json(j) => j,
+        }
+    }
+}
+
+impl Act for CommandActor {
+    type Param = Primitive;
+    type Config = CommandAction;
+    type Return = String;
+
+    fn build(config: &CommandAction, parameter: Primitive) -> Result<Self, ActError> {
+        Ok(
+            Self {
+                shell: "bash".to_owned(),
+                run: config.run.clone(),
+                variable: Self::primitive_to_string(parameter),
+            }
+        )
+    }
+
+    fn run(self) -> Self::Return {
+        let output = Command::new(&self.shell)
+            .args(["-c", &self.run])
+            .env(VALUE_ENV_VAR, &self.variable)
+            .output()
+            .expect(&format!("Cannot run `{}`", &self.run));
+        if !output.stderr.is_empty() {
+            log::error!("Error running `{}`: {}", &self.run, String::from_utf8(output.stderr).unwrap_or_else(|_| "<non utf-8 stderr output>".to_owned()))
+        }
+        let result = String::from_utf8(output.stdout).expect(&format!("Cannot parse stdout from `{}` as UTF-8", self.run));
+        log::debug!("CommandActor ran `{}` (${}=\"{}\") -> `{}`", &self.run, VALUE_ENV_VAR, &self.variable, &result);
+        result
+    }
+}
--- a/backend/src/runtime/communication.rs
+++ b/backend/src/runtime/communication.rs
@ -0,0 +1,26 @@
+use std::sync::mpsc::Sender;
+
+use usdpl_back::core::serdes::Primitive;
+
+use crate::config::{AboutConfig, ElementConfig};
+
+pub enum QueueAction {
+    GetAbout {
+        respond_to: Sender<AboutConfig>,
+    },
+    DoUpdate {
+        index: usize,
+        value: Primitive,
+    },
+    DoReload {
+        respond_to: Sender<Vec<ElementConfig>>
+    },
+    SetCallback {
+        index: usize,
+        respond_to: Sender<Primitive>,
+    }
+}
+
+pub struct QueueItem {
+    pub action: QueueAction,
+}
--- a/backend/src/runtime/executor.rs
+++ b/backend/src/runtime/executor.rs
@ -0,0 +1,121 @@
+use std::thread;
+use std::sync::mpsc::{self, Receiver, Sender};
+
+use crate::config::{BaseConfig, ElementConfig};
+use super::{QueueItem, QueueAction, Act};
+use super::{ResultRouter, RouterCommand};
+
+pub struct RuntimeExecutor {
+    config_data: BaseConfig,
+    tasks_receiver: Receiver<QueueItem>
+}
+
+impl RuntimeExecutor {
+    pub fn new(conf: BaseConfig) -> (Self, Sender<QueueItem>) {
+        let (tx, rx) = mpsc::channel();
+        (Self {
+            config_data: conf,
+            tasks_receiver: rx,
+        }, tx)
+    }
+
+    pub fn spawn(self) -> thread::JoinHandle<()> {
+        thread::spawn(move || self.run_loop())
+    }
+
+    fn run_loop(self) {
+        let (mut state, tasks_receiver) = self.split();
+        state.populate_router();
+        for item in tasks_receiver.iter() {
+            state.handle_item(item);
+        }
+    }
+
+    fn split(self) -> (ExecutorState, Receiver<QueueItem>) {
+        (
+            ExecutorState {
+                result_handler: ExecutorState::build_router(self.config_data.items().len()),
+                config_data: self.config_data,
+            },
+            self.tasks_receiver
+        )
+    }
+}
+
+struct ExecutorState {
+    config_data: BaseConfig,
+    result_handler: Sender<RouterCommand>,
+}
+
+impl ExecutorState {
+    fn handle_item(&mut self, item: QueueItem) {
+        match item.action {
+            QueueAction::GetAbout { respond_to } => {
+                respond_to.send(self.config_data.get_about().clone()).unwrap_or(());
+            },
+            QueueAction::DoUpdate { index, value } => {
+                if let Some(item) = self.config_data.get_item(index) {
+                    match super::Actor::build(item, (index, value)) {
+                        Ok(act) => {
+                            let respond_to = self.result_handler.clone();
+                            thread::spawn(move || {
+                                let result = act.run();
+                                match respond_to.send(RouterCommand::HandleResult{index, result}) {
+                                    Ok(_) => {},
+                                    Err(_) => log::warn!("Failed to send DoUpdate response for item #{}", index),
+                                }
+                            });
+                        },
+                        Err(e) => log::error!("Failed to build DoUpdate actor for item #{}: {}", index, e)
+                    }
+                } else {
+                    log::warn!("Received DoUpdate on non-existent item #{} with value `{}`", index, super::primitive_utils::debug(&value))
+                }
+            },
+            QueueAction::DoReload { respond_to } => {
+                self.config_data = BaseConfig::load(crate::consts::FILEPATH);
+                self.populate_router();
+                respond_to.send(self.config_data.items().clone()).unwrap_or(());
+            },
+            QueueAction::SetCallback { index, respond_to } => {
+                if let Some(elem) = self.config_data.get_item(index) {
+                    let display_of = match elem {
+                        ElementConfig::ResultDisplay(c) => c.result_of,
+                        _ => index,
+                    };
+                    if let Err(_) = self.result_handler.send(
+                        RouterCommand::AddSender {
+                            index: display_of,
+                            sender: respond_to,
+                    }) {
+                        log::warn!("Failed to send to ResultRouter, rebuilding router");
+                        self.result_handler = ExecutorState::build_router(self.config_data.items().len());
+                    }
+                }
+            }
+        }
+    }
+
+    fn build_router(items_len: usize) -> Sender<RouterCommand> {
+        let router = ResultRouter::build(&(), items_len).unwrap();
+        let result = router.run();
+        result
+    }
+
+    fn populate_router(&mut self) {
+        if let Err(_) = self.result_handler.send(RouterCommand::Clear{}) {
+            return;
+        }
+        // start reading displays with periodic actions
+        for (index, item) in self.config_data.items().iter().enumerate() {
+            match item {
+                ElementConfig::ReadingDisplay(r) => {
+                    if let Ok(actor) = super::PeriodicActor::build(r, (index, self.result_handler.clone())) {
+                        actor.run();
+                    }
+                },
+                _ => {}
+            }
+        }
+    }
+}
--- a/backend/src/runtime/mod.rs
+++ b/backend/src/runtime/mod.rs
@ -0,0 +1,14 @@
+mod actor;
+mod command_actor;
+mod communication;
+mod executor;
+mod periodic_actor;
+mod primitive_utils;
+mod result_router;
+
+pub use actor::{Actor, Act, ActError, ActorType};
+pub use command_actor::CommandActor;
+pub use communication::{QueueItem, QueueAction};
+pub use executor::RuntimeExecutor;
+pub use periodic_actor::PeriodicActor;
+pub use result_router::{ResultRouter, RouterCommand};
--- a/backend/src/runtime/periodic_actor.rs
+++ b/backend/src/runtime/periodic_actor.rs
@ -0,0 +1,57 @@
+use std::sync::mpsc::Sender;
+use std::time::Duration;
+
+use usdpl_back::core::serdes::Primitive;
+
+use crate::config::ReadingConfig;
+use super::{Act, ActError, ActorType, RouterCommand};
+
+pub struct PeriodicActor {
+    config: ReadingConfig,
+    result_handler: Sender<RouterCommand>,
+    index: usize,
+}
+
+impl Act for PeriodicActor {
+    type Param = (usize, Sender<RouterCommand>);
+    type Config = ReadingConfig;
+    type Return = ();
+
+    fn build(config: &Self::Config, parameter: Self::Param) -> Result<Self, ActError> {
+        ActorType::build(&config.on_period, Primitive::Empty)?;
+        Ok(
+            Self {
+                config: config.clone(),
+                result_handler: parameter.1,
+                index: parameter.0,
+            }
+        )
+    }
+
+    fn run(self) -> Self::Return {
+        std::thread::spawn(move || {
+            let sleep_duration = Duration::from_millis(self.config.period_ms);
+            loop {
+                let actor = match ActorType::build(&self.config.on_period, Primitive::Empty) {
+                    Ok(x) => x,
+                    Err(e) => {
+                        log::error!("PeriodicActor failed to build for item #{}: {}", self.index, e);
+                        break;
+                    }
+                };
+                let result = actor.run();
+                match self.result_handler.send(RouterCommand::HandleResult {
+                    index: self.index, result
+                }) {
+                    Ok(_) => {},
+                    Err(_e) => {
+                        log::warn!("PeriodicActor failed to handle result for item #{}", self.index);
+                        break;
+                    }
+                }
+                std::thread::sleep(sleep_duration);
+            }
+            log::info!("PeriodicActor completed for #{}", self.index);
+        });
+    }
+}
--- a/backend/src/runtime/primitive_utils.rs
+++ b/backend/src/runtime/primitive_utils.rs
@ -0,0 +1,84 @@
+use usdpl_back::core::serdes::Primitive;
+
+//use super::ActError;
+
+/*macro_rules! map_primitive_number_impl {
+    ($type:ty, $type_name:literal, $fn_name:ident) => {
+        pub fn $fn_name (param: Primitive) -> Result<$type, ActError> {
+            match param {
+                Primitive::I64(a) => Ok(a as $type),
+                Primitive::I32(a) => Ok(a as $type),
+                Primitive::U64(a) => Ok(a as $type),
+                Primitive::U32(a) => Ok(a as $type),
+                Primitive::F64(a) => Ok(a as $type),
+                Primitive::F32(a) => Ok(a as $type),
+                _ => Err(format!("Parameter must be {} type", $type_name))
+            }
+        }
+    }
+}*/
+
+/*macro_rules! map_primitive_impl {
+    ($type:ty, $primitive:ident, $type_name:literal, $fn_name:ident) => {
+        pub fn $fn_name (param: Primitive) -> Result<$type, ActError> {
+            match param {
+                Primitive::$primitive(a) => Ok(a),
+                _ => Err(format!("Parameter must be {} type", $type_name))
+            }
+        }
+    }
+}*/
+
+//map_primitive_impl!{bool, Bool, "boolean", try_primitive_bool}
+
+//map_primitive_impl!{String, String, "string", try_primitive_string}
+
+//map_primitive_number_impl!{usize, "uinteger", try_primitive_usize}
+
+#[inline]
+pub fn debug(primitive: &Primitive) -> String {
+    match primitive {
+        Primitive::Empty => "Primitive::Empty".to_owned(),
+        Primitive::String(x) => format!("Primitive::String(`{}`)", x),
+        Primitive::F32(x) => format!("Primitive::F32(`{}`)", x),
+        Primitive::F64(x) => format!("Primitive::F64(`{}`)", x),
+        Primitive::U32(x) => format!("Primitive::U32(`{}`)", x),
+        Primitive::U64(x) => format!("Primitive::U64(`{}`)", x),
+        Primitive::I32(x) => format!("Primitive::I32(`{}`)", x),
+        Primitive::I64(x) => format!("Primitive::I64(`{}`)", x),
+        Primitive::Bool(x) => format!("Primitive::Bool(`{}`)", x),
+        Primitive::Json(x) => format!("Primitive::Json(`{}`)", x),
+    }
+}
+
+/*#[inline]
+pub fn display(primitive: Primitive) -> String {
+    match primitive {
+        Primitive::Empty => "".to_owned(),
+        Primitive::String(x) => x,
+        Primitive::F32(x) => x.to_string(),
+        Primitive::F64(x) => x.to_string(),
+        Primitive::U32(x) => x.to_string(),
+        Primitive::U64(x) => x.to_string(),
+        Primitive::I32(x) => x.to_string(),
+        Primitive::I64(x) => x.to_string(),
+        Primitive::Bool(x) => x.to_string(),
+        Primitive::Json(x) => x,
+    }
+}*/
+
+#[inline]
+pub fn clone(primitive: &Primitive) -> Primitive {
+    match primitive {
+        Primitive::Empty => Primitive::Empty,
+        Primitive::String(x) => Primitive::String(x.clone()),
+        Primitive::F32(x) => Primitive::F32(*x),
+        Primitive::F64(x) => Primitive::F64(*x),
+        Primitive::U32(x) => Primitive::U32(*x),
+        Primitive::U64(x) => Primitive::U64(*x),
+        Primitive::I32(x) => Primitive::I32(*x),
+        Primitive::I64(x) => Primitive::I64(*x),
+        Primitive::Bool(x) => Primitive::Bool(*x),
+        Primitive::Json(x) => Primitive::Json(x.clone()),
+    }
+}
--- a/backend/src/runtime/result_router.rs
+++ b/backend/src/runtime/result_router.rs
@ -0,0 +1,133 @@
+use std::sync::mpsc::{self, Receiver, Sender};
+
+use usdpl_back::core::serdes::Primitive;
+
+//use crate::config::ElementConfig;
+use super::{Act, ActError};
+
+const MAX_HANDLERS_PER_ITEM: usize = 8;
+
+pub enum RouterCommand {
+    AddSender {
+        index: usize,
+        sender: Sender<Primitive>,
+    },
+    HandleResult {
+        index: usize,
+        result: Primitive,
+    },
+    Clear{}
+}
+
+pub struct ResultRouter {
+    comm: Receiver<RouterCommand>,
+    senders: Vec<[Option<Sender<Primitive>>; MAX_HANDLERS_PER_ITEM]>,
+    comm_tx: Option<Sender<RouterCommand>>,
+    cache: Vec<Option<Primitive>>,
+}
+
+impl ResultRouter {
+    fn all_senders_none(senders: &[Option<Sender<Primitive>>]) -> bool {
+        let mut all_none = true;
+        for s in senders.iter() {
+            all_none &= s.is_none();
+        }
+        all_none
+    }
+}
+
+impl Act for ResultRouter {
+    type Param = usize;
+    type Config = ();
+    type Return = Sender<RouterCommand>;
+
+    fn build(_config: &Self::Config, parameter: Self::Param) -> Result<Self, ActError> {
+        let (tx, rx) = mpsc::channel();
+        let mut cache_vec = Vec::with_capacity(parameter);
+        for _ in 0..parameter {
+            cache_vec.push(None);
+        }
+        Ok(Self {
+            comm: rx,
+            senders: vec![[(); MAX_HANDLERS_PER_ITEM].map(|_| None); parameter],
+            comm_tx: Some(tx),
+            cache: cache_vec,
+        })
+    }
+
+    fn run(mut self) -> Self::Return {
+        let result = self.comm_tx.take().unwrap();
+        std::thread::spawn(move || {
+            log::debug!("ResultRouter starting");
+            for command in self.comm.iter() {
+                match command {
+                    RouterCommand::AddSender { index, sender } => {
+                        log::debug!("Handling AddSender for item #{}", index);
+                        if let Some(senders) = self.senders.get_mut(index) {
+                            // send cached value, if available
+                            if self.cache[index].is_some() {
+                                log::debug!("Routing cached result for item #{}", index);
+                                let result = self.cache[index].take().unwrap();
+                                match sender.send(result) {
+                                    Ok(_) => {},
+                                    Err(e) => {
+                                        self.cache[index] = Some(e.0);
+                                        log::debug!("ResultRouter ignoring AddSender since sending cached value failed");
+                                        continue;
+                                    },
+                                }
+                            }
+                            // save sender for future results
+                            let mut was_set = false;
+                            'inner_loop: for sender_opt in senders {
+                                if sender_opt.is_none() {
+                                    *sender_opt = Some(sender);
+                                    was_set = true;
+                                    break 'inner_loop;
+                                }
+                            }
+                            if !was_set {
+                                log::warn!("ResultRouter could not add another sender for index {}", index);
+                            }
+                        } else {
+                            log::warn!("ResultRouter got AddSender command for invalid index {} (max: {})", index, self.senders.len());
+                        }
+                    }
+                    RouterCommand::HandleResult {index, result} => {
+                        log::debug!("Handling HandleResult for item #{}", index);
+                        if let Some(senders) = self.senders.get_mut(index) {
+                            if Self::all_senders_none(senders) {
+                                self.cache[index] = Some(result);
+                                log::debug!("Cached result for item #{}", index);
+                            } else {
+                                for (i, sender_opt) in senders.iter_mut().enumerate() {
+                                    if let Some(sender) = sender_opt {
+                                        match sender.send(super::primitive_utils::clone(&result)) {
+                                            Ok(_) => {},
+                                            Err(_) => {
+                                                log::debug!("Removing sender {} because it seems closed", i);
+                                                *sender_opt = None;
+                                            }
+                                        }
+                                    }
+                                }
+                                log::debug!("Routed result for item #{}", index);
+                            }
+                        } else {
+                            log::warn!("ResultRouter got AddSender command for invalid index {} (max: {})", index, self.senders.len());
+                        }
+                    },
+                    RouterCommand::Clear {} => {
+                        log::debug!("Handling Clear");
+                        for i in 0..self.senders.len() {
+                            self.senders[i] = [(); MAX_HANDLERS_PER_ITEM].map(|_| None);
+                            self.cache[i] = None;
+                        }
+                    }
+                }
+            }
+            log::warn!("ResultRouter completed");
+        });
+        result
+    }
+}
--- a/kaylon.json
+++ b/kaylon.json
@ -0,0 +1,57 @@
+{
+  "api-version": "v0.0.0",
+  "items": [
+    {
+      "element": "button",
+      "title": "Test Button",
+      "on_click": {
+        "action": "command",
+        "run": "echo 'hello button'"
+      }
+    },
+    {
+      "element": "toggle",
+      "title": "Test Toggle",
+      "description": "Toggle description",
+      "on_toggle": {
+        "action": "command",
+        "run": "echo 'hello toggle ${KAYLON_VALUE}'"
+      }
+    },
+    {
+      "element": "slider",
+      "title": "Test Slider",
+      "min": 0,
+      "max": 3,
+      "notches": null,
+      "on_set": {
+        "action": "command",
+        "run": "echo 'hello slider'"
+      }
+    },
+    {
+      "element": "reading",
+      "title": "Test Reading",
+      "period_ms": 10000,
+      "on_period": {
+        "action": "command",
+        "run": "echo 'hello reading'"
+      }
+    },
+    {
+      "element": "result-display",
+      "title": "Test Result",
+      "result_of": 1
+    }
+  ],
+  "about": {
+    "name": "Test name",
+    "version": "v0.42.0",
+    "description": "Test description",
+    "url": "https://github.com/NGnius/kaylon",
+    "authors": [
+      "NGnius <ngniusness@gmail.com>"
+    ],
+    "license": "MIT"
+  }
+}
--- a/main.py
+++ b/main.py
@ -11,6 +11,6 @@ class Plugin:
    # Asyncio-compatible long-running code, executed in a task when the plugin is loaded
    async def _main(self):
        # startup
-        self.backend_proc = subprocess.Popen([PARENT_DIR + "/bin/backend"])
+        #self.backend_proc = subprocess.Popen([PARENT_DIR + "/bin/backend"])
        while True:
-            asyncio.sleep(1)
+            await asyncio.sleep(1)
--- a/package.json
+++ b/package.json
@ -38,7 +38,7 @@
    "typescript": "^4.6.4"
  },
  "dependencies": {
-    "decky-frontend-lib": "^1.0.1",
+    "decky-frontend-lib": "*",
    "react-icons": "^4.3.1",
    "usdpl-front": "file:./src/usdpl_front"
  },
--- a/server/build.sh
+++ b/server/build.sh
@ -1,6 +0,0 @@
-#!/bin/bash
-
-cargo build --release
-mkdir ../bin
-# TODO replace "backend" \/ with binary name
-cp ./target/release/backend ../bin/backend
--- a/server/src/config/about.rs
+++ b/server/src/config/about.rs
@ -1,11 +0,0 @@
-use serde::{Serialize, Deserialize};
-
-#[derive(Serialize, Deserialize, Clone)]
-pub struct AboutConfig {
-    pub name: String,
-    pub version: String,
-    pub description: String,
-    pub url: Option<String>,
-    pub author: Option<String>,
-    pub license: Option<String>,
-}
--- a/server/src/config/base.rs
+++ b/server/src/config/base.rs
@ -1,13 +0,0 @@
-use serde::{Serialize, Deserialize};
-
-use super::{ElementConfig, AboutConfig};
-
-#[derive(Serialize, Deserialize, Clone)]
-#[serde(tag = "api-version")]
-pub enum BaseConfig {
-    #[serde(rename = "v0.0.0")]
-    V0 {
-        items: Vec<ElementConfig>,
-        about: AboutConfig,
-    },
-}
--- a/server/src/main.rs
+++ b/server/src/main.rs
@ -1,27 +0,0 @@
-mod config;
-
-use simplelog::{WriteLogger, LevelFilter};
-
-use usdpl_back::Instance;
-use usdpl_back::core::serdes::Primitive;
-
-const PORT: u16 = 54321; // TODO replace with something unique
-
-const PACKAGE_NAME: &'static str = env!("CARGO_PKG_NAME");
-const PACKAGE_VERSION: &'static str = env!("CARGO_PKG_VERSION");
-
-fn main() -> Result<(), ()> {
-    let log_filepath = format!("/tmp/{}.log", PACKAGE_NAME);
-    WriteLogger::init(
-        #[cfg(debug_assertions)]{LevelFilter::Debug},
-        #[cfg(not(debug_assertions))]{LevelFilter::Info},
-        Default::default(),
-        std::fs::File::create(&log_filepath).unwrap()
-    ).unwrap();
-
-    log::info!("Starting back-end ({} v{})", PACKAGE_NAME, PACKAGE_VERSION);
-    println!("Starting back-end ({} v{})", PACKAGE_NAME, PACKAGE_VERSION);
-    Instance::new(PORT)
-        .register("hello", |_: Vec<Primitive>| vec![format!("Hello {}", PACKAGE_NAME).into()])
-        .run_blocking()
-}
--- a/src/backend.ts
+++ b/src/backend.ts
@ -1,4 +1,4 @@
-import {init_usdpl, target, init_embedded, call_backend} from "usdpl-front";
+import {init_usdpl, target_usdpl, init_embedded, call_backend} from "usdpl-front";

 const USDPL_PORT: number = 25717;

@ -20,7 +20,7 @@ export async function initBackend() {
    // init usdpl
    await init_embedded();
    init_usdpl(USDPL_PORT);
-    console.log("USDPL started for framework: " + target());
+    console.log("USDPL started for framework: " + target_usdpl());
    //setReady(true);
 }

@ -29,7 +29,7 @@ export type CAbout = {
    version: string;
    description: string;
    url: string | null;
-    author: string | null;
+    authors: string[];
    license: string | null;
 }

@ -58,18 +58,24 @@ export type CReading = {
    period_ms: number;
 }

-export type CElement = CButton | CToggle | CSlider | CReading;
+export type CResultDisplay = {
+    element: string; // "result-display"
+    title: string;
+    result_of: number;
+}
+
+export type CElement = CButton | CToggle | CSlider | CReading | CResultDisplay;

 export async function getElements(): Promise<CElement[]> {
-    return await call_backend("get_items", []);
+    return (await call_backend("get_items", []))[0];
 }

 export async function onUpdate(index: number, value: any): Promise<any> {
    return (await call_backend("on_update", [index, value]))[0];
 }

-export async function getReading(index: number): Promise<string | null> {
-    return (await call_backend("get_reading", [index]))[0];
+export async function getDisplay(index: number): Promise<string | null> {
+    return (await call_backend("get_display", [index]))[0];
 }

 export async function getAbout(): Promise<CAbout> {
@ -77,5 +83,5 @@ export async function getAbout(): Promise<CAbout> {
 }

 export async function reload(): Promise<CElement[]> {
-    return await call_backend("reload", []);
+    return (await call_backend("reload", []))[0];
 }
--- a/src/index.tsx
+++ b/src/index.tsx
@ -1,7 +1,7 @@
 import {
  ButtonItem,
  definePlugin,
-  DialogButton,
+  //DialogButton,
  //Menu,
  //MenuItem,
  PanelSection,
@ -19,37 +19,54 @@ import {
 import { VFC, useState } from "react";
 import { GiWashingMachine } from "react-icons/gi";

-import { call_backend } from "usdpl-front";
+import { get_value, set_value } from "usdpl-front";
 import * as backend from "./backend";

-// interface AddMethodArgs {
-//   left: number;
-//   right: number;
-// }
-
 const FieldWithSeparator = joinClassNames(gamepadDialogClasses.Field, gamepadDialogClasses.WithBottomSeparatorStandard);

+const DISPLAY_KEY = "display";
+const VALUE_KEY = "value";
+
 let items: backend.CElement[] = [];
+let about: backend.CAbout | null = null;
+
+let update = () => {};
+
+function displayCallback(index: number) {
+  return (newVal: any) => {
+    set_value(DISPLAY_KEY + index.toString(), newVal);
+    backend.resolve(backend.getDisplay(index), displayCallback(index));
+    console.log("Got display for " + index.toString(), newVal);
+    update();
+  }
+}
+
+// init USDPL WASM frontend
+// this is required to interface with the backend
+(async () => {
+  await backend.initBackend();
+  let about_promise = backend.getAbout();
+  let elements_promise = backend.getElements();
+  about = await about_promise;
+  console.log("KAYLON: got about", about);
+  let result = await elements_promise;
+  console.log("KAYLON: got elements", result);
+  if (result != null) {
+    items = await backend.getElements();
+    for (let i = 0; i < items.length; i++) {
+      console.log("KAYLON: req display for item #" + i.toString());
+      backend.resolve(backend.getDisplay(i), displayCallback(i));
+    }
+  } else {
+    console.warn("KAYLON: backend connection failed");
+  }
+})();

 const Content: VFC<{ serverAPI: ServerAPI }> = ({}) => {
-  // const [result, setResult] = useState<number | undefined>();
-
-  // const onClick = async () => {
-  //   const result = await serverAPI.callPluginMethod<AddMethodArgs, number>(
-  //     "add",
-  //     {
-  //       left: 2,
-  //       right: 2,
-  //     }
-  //   );
-  //   if (result.success) {
-  //     setResult(result.result);
-  //   }
-  // };

  const [triggerInternal, updateInternal] = useState<boolean>(false);

-  function update() {
+  update = () => {
    updateInternal(!triggerInternal);
  }

@ -57,34 +74,38 @@ const Content: VFC<{ serverAPI: ServerAPI }> = ({}) => {
    update();
  }

-  // call hello callback on backend
-  (async () => {
-    let response = await call_backend("hello", []);
-    console.log("Backend says:", response);
-  })();
-
  return (
-    <PanelSection title="Panel Section">
+    <PanelSection>
      {items.map(
        (elem, i) => {
          return <PanelSectionRow>{buildHtmlElement(elem, i, updateIdc)}</PanelSectionRow>
        })
      }
+      { about != null && buildAbout() }
+      <PanelSectionRow>
+        <ButtonItem
+          layout="below"
+          onClick={(_: MouseEvent) => {
+            backend.resolve(backend.reload(),
+              (reload_items: backend.CElement[]) => {
+                items = reload_items;
+                console.log("KAYLON: got elements", reload_items);
+                update();
+              });
+            backend.resolve(backend.getAbout(),
+              (new_about: backend.CAbout) => {
+                about = new_about;
+                console.log("KAYLON: got about", about);
+                update();
+              });
+          }}>
+          Reload
+        </ButtonItem>
+      </PanelSectionRow>
    </PanelSection>
  );
 };

-const DeckyPluginRouterTest: VFC = () => {
-  return (
-    <div style={{ marginTop: "50px", color: "white" }}>
-      Hello World!
-      <DialogButton onClick={() => {}}>
-        Go to Store
-      </DialogButton>
-    </div>
-  );
-};
-
 function buildHtmlElement(element: backend.CElement, index: number, updateIdc: any) {
  switch (element.element) {
    case "button":
@ -95,8 +116,11 @@ function buildHtmlElement(element: backend.CElement, index: number, updateIdc: a
      return buildToggle(element as backend.CToggle, index, updateIdc);
    case "reading":
      return buildReading(element as backend.CReading, index, updateIdc);
+    case "result-display":
+      return buildResultDisplay(element as backend.CResultDisplay, index, updateIdc);
  }
-  return "Unsupported";
+  console.error("KAYLON: Unsupported element", element);
+  return <div>Unsupported</div>;
 }

 function buildButton(element: backend.CButton, index: number, updateIdc: any) {
@ -110,62 +134,175 @@ function buildButton(element: backend.CButton, index: number, updateIdc: any) {
 }

 function buildSlider(element: backend.CSlider, index: number, updateIdc: any) {
+  const KEY = VALUE_KEY + index.toString();
+  if (get_value(KEY) == null) {
+    set_value(KEY, element.min);
+  }
  return (
    <SliderField
      label={element.title}
-      value={element.min}
+      value={get_value(KEY)}
      max={element.max}
      min={element.min}
      showValue={true}
      onChange={(value: number) => {
-        backend.resolve(backend.onUpdate(index, value), updateIdc)
+        backend.resolve(backend.onUpdate(index, value), updateIdc);
+        set_value(KEY, value);
      }}
    />
  );
 }

 function buildToggle(element: backend.CToggle, index: number, updateIdc: any) {
+  const KEY = VALUE_KEY + index.toString();
+  if (get_value(KEY) == null) {
+    set_value(KEY, false);
+  }
  return (
    <ToggleField
-      checked={false}
+      checked={get_value(KEY)}
      label={element.title}
      description={element.description!}
      onChange={(value: boolean) => {
-        backend.resolve(backend.onUpdate(index, value), updateIdc)
+        backend.resolve(backend.onUpdate(index, value), updateIdc);
+        set_value(KEY, value);
      }}
    />
  );
 }

-function buildReading(element: backend.CReading, _index: number, _updateIdc: any) {
+function buildReading(element: backend.CReading, index: number, _updateIdc: any) {
  return (
    <div className={FieldWithSeparator}>
      <div className={gamepadDialogClasses.FieldLabelRow}>
        <div className={gamepadDialogClasses.FieldLabel}>{element.title}</div>
-        <div className={gamepadDialogClasses.FieldChildren}>{"idk"}</div>
+        <div className={gamepadDialogClasses.FieldChildren}>{get_value(DISPLAY_KEY + index.toString())}</div>
      </div>
    </div>
  );
 }

-export default definePlugin((serverApi: ServerAPI) => {
-  serverApi.routerHook.addRoute("/decky-plugin-test", DeckyPluginRouterTest, {
-    exact: true,
+function buildResultDisplay(element: backend.CResultDisplay, index: number, _updateIdc: any) {
+  return (
+    <div className={FieldWithSeparator}>
+      <div className={gamepadDialogClasses.FieldLabelRow}>
+        <div className={gamepadDialogClasses.FieldLabel}>{element.title}</div>
+        <div className={gamepadDialogClasses.FieldChildren}>{get_value(DISPLAY_KEY + index.toString())}</div>
+      </div>
+    </div>
+  );
+}
+
+function buildAbout() {
+  if (about == null) {
+    return [];
+  } else {
+    let elements = [
+      <div className={staticClasses.PanelSectionTitle}>
+        About
+      </div>,
+      <PanelSectionRow>
+        <div className={FieldWithSeparator}>
+          <div className={gamepadDialogClasses.FieldLabelRow}>
+            <div className={gamepadDialogClasses.FieldLabel}>Name</div>
+            <div className={gamepadDialogClasses.FieldChildren}>{about.name}</div>
+          </div>
+        </div>
+      </PanelSectionRow>,
+      <PanelSectionRow>
+        <div className={FieldWithSeparator}>
+          <div className={gamepadDialogClasses.FieldLabelRow}>
+            <div className={gamepadDialogClasses.FieldLabel}>Version</div>
+            <div className={gamepadDialogClasses.FieldChildren}>{about.version}</div>
+          </div>
+        </div>
+      </PanelSectionRow>,
+      <PanelSectionRow>
+        <div className={FieldWithSeparator}>
+          <div className={gamepadDialogClasses.FieldLabelRow}>
+            <div className={gamepadDialogClasses.FieldLabel}>Description</div>
+            <div className={gamepadDialogClasses.FieldDescription}>{about.description}</div>
+          </div>
+        </div>
+      </PanelSectionRow>
+    ];
+    if (about.url != null) {
+      elements.push(
+        <PanelSectionRow>
+          <div className={FieldWithSeparator}>
+            <div className={gamepadDialogClasses.FieldLabelRow}>
+              <div className={gamepadDialogClasses.FieldLabel}>URL</div>
+              <div className={gamepadDialogClasses.FieldDescription}>{about.url}</div>
+            </div>
+          </div>
+        </PanelSectionRow>
+      );
+    }
+    if (about.authors.length > 1) {
+      let authors = about.authors.map((elem, i) => {
+        if (i == about!.authors.length - 1) {
+          return <p>{elem}</p>;
+        } else {
+          return <span>{elem}</span>;
+        }
      });
+      elements.push(
+        <PanelSectionRow>
+          <div className={FieldWithSeparator}>
+            <div className={gamepadDialogClasses.FieldLabelRow}>
+              <div className={gamepadDialogClasses.FieldLabel}>Authors</div>
+              <div className={gamepadDialogClasses.FieldDescription}>{authors}</div>
+            </div>
+          </div>
+        </PanelSectionRow>
+      );
+    } else if (about.authors.length == 1) {
+      elements.push(
+        <PanelSectionRow>
+          <div className={FieldWithSeparator}>
+            <div className={gamepadDialogClasses.FieldLabelRow}>
+              <div className={gamepadDialogClasses.FieldLabel}>Author</div>
+              <div className={gamepadDialogClasses.FieldDescription}>{about.authors[0]}</div>
+            </div>
+          </div>
+        </PanelSectionRow>
+      );
+    } else {
+      elements.push(
+        <PanelSectionRow>
+          <div className={FieldWithSeparator}>
+            <div className={gamepadDialogClasses.FieldLabelRow}>
+              <div className={gamepadDialogClasses.FieldLabel}>Author</div>
+              <div className={gamepadDialogClasses.FieldDescription}>NGnius</div>
+            </div>
+          </div>
+        </PanelSectionRow>
+      );
+    }

-  // init USDPL WASM frontend
-  // this is required to interface with the backend
-  (async () => {
-    await backend.initBackend();
-    items = await backend.getElements();
-  })();
+    if (about.license != null) {
+      elements.push(
+        <PanelSectionRow>
+          <div className={FieldWithSeparator}>
+            <div className={gamepadDialogClasses.FieldLabelRow}>
+              <div className={gamepadDialogClasses.FieldLabel}>License</div>
+              <div className={gamepadDialogClasses.FieldChildren}>{about.license}</div>
+            </div>
+          </div>
+        </PanelSectionRow>
+      );
+    }
+    return elements;
+  }
+}

+export default definePlugin((serverApi: ServerAPI) => {
  return {
-    title: <div className={staticClasses.Title}>Example Plugin</div>,
+    title: <div className={staticClasses.Title}>{about == null? "Kaylon": about.name}</div>,
    content: <Content serverAPI={serverApi} />,
    icon: <GiWashingMachine />,
    onDismount() {
-      serverApi.routerHook.removeRoute("/decky-plugin-test");
+      //serverApi.routerHook.removeRoute("/decky-plugin-test");
    },
  };
 });
--- a/src/usdpl_front/README.md
+++ b/src/usdpl_front/README.md
@ -0,0 +1,9 @@
+[![Crates.io](https://img.shields.io/crates/v/usdpl-front?style=flat-square)](https://crates.io/crates/usdpl-front)
+
+# usdpl-front-front
+
+Front-end library to be called from Javascript.
+Targets WASM.
+
+In true Javascript tradition, this part of the library does not support error handling.
+
--- a/src/usdpl_front/package.json
+++ b/src/usdpl_front/package.json
@ -4,7 +4,7 @@
    "NGnius (Graham) <ngniusness@gmail.com>"
  ],
  "description": "Universal Steam Deck Plugin Library front-end designed for WASM",
-  "version": "0.6.0",
+  "version": "0.6.2",
  "license": "GPL-3.0-only",
  "repository": {
    "type": "git",
--- a/src/usdpl_front/usdpl_front.d.ts
+++ b/src/usdpl_front/usdpl_front.d.ts
@ -9,7 +9,25 @@ export function init_usdpl(port: number): void;
 * Get the targeted plugin framework, or "any" if unknown
 * @returns {string}
 */
-export function target(): string;
+export function target_usdpl(): string;
+/**
+* Get the UDSPL front-end version
+* @returns {string}
+*/
+export function version_usdpl(): string;
+/**
+* Get the targeted plugin framework, or "any" if unknown
+* @param {string} key
+* @param {any} value
+* @returns {any}
+*/
+export function set_value(key: string, value: any): any;
+/**
+* Get the targeted plugin framework, or "any" if unknown
+* @param {string} key
+* @returns {any}
+*/
+export function get_value(key: string): any;
 /**
 * Call a function on the back-end.
 * Returns null (None) if this fails for any reason.
@ -24,7 +42,10 @@ export type InitInput = RequestInfo | URL | Response | BufferSource | WebAssembl
 export interface InitOutput {
  readonly memory: WebAssembly.Memory;
  readonly init_usdpl: (a: number) => void;
-  readonly target: (a: number) => void;
+  readonly target_usdpl: (a: number) => void;
+  readonly version_usdpl: (a: number) => void;
+  readonly set_value: (a: number, b: number, c: number) => number;
+  readonly get_value: (a: number, b: number) => number;
  readonly call_backend: (a: number, b: number, c: number, d: number) => number;
  readonly __wbindgen_export_0: (a: number) => number;
  readonly __wbindgen_export_1: (a: number, b: number, c: number) => number;
--- a/src/usdpl_front/usdpl_front.js
+++ b/src/usdpl_front/usdpl_front.js
--- a/src/usdpl_front/usdpl_front_bg.wasm
+++ b/src/usdpl_front/usdpl_front_bg.wasm
--- a/src/usdpl_front/usdpl_front_bg.wasm.d.ts
+++ b/src/usdpl_front/usdpl_front_bg.wasm.d.ts
@ -2,7 +2,10 @@
 /* eslint-disable */
 export const memory: WebAssembly.Memory;
 export function init_usdpl(a: number): void;
-export function target(a: number): void;
+export function target_usdpl(a: number): void;
+export function version_usdpl(a: number): void;
+export function set_value(a: number, b: number, c: number): number;
+export function get_value(a: number, b: number): number;
 export function call_backend(a: number, b: number, c: number, d: number): number;
 export function __wbindgen_export_0(a: number): number;
 export function __wbindgen_export_1(a: number, b: number, c: number): number;