working set image api

src/api.rs

@@ -1,12 +1,17 @@
+use crate::imageproc::{DiffusionMatrix, Ditherer, EInkImage, ErrorDiffusionDither};
 use axum::extract::Multipart;
 use axum::http::StatusCode;
 use axum::response::IntoResponse;
 use axum::{extract::State, response::Response, routing::post, Router};
-use image::ImageReader;
+use image::{ImageReader, RgbImage};
 use std::io::Cursor;
+use std::time::Duration;
+use tracing::{error, info, debug, instrument};
 
 use crate::display::EInkPanel;
-use std::sync::{Arc, Mutex};
+use std::sync::Arc;
+use tokio::sync::mpsc::{self, Receiver, Sender};
+use tokio::task::JoinHandle;
 
 pub enum ImageFormFields {
     DitherType,
@@ -15,17 +20,42 @@ pub enum ImageFormFields {
 
 #[derive(Clone)]
 pub struct Context {
-    display: Arc<Mutex<Box<dyn EInkPanel + Send>>>,
+    display_channel: Sender<DisplaySetCommand>,
+    display_task: Arc<JoinHandle<()>>,
 }
+
 impl Context {
     #[must_use]
-    pub fn new(w: Box<dyn EInkPanel + Send>) -> Self {
+    pub fn new(disp: Box<dyn EInkPanel + Send>) -> Self {
+        let (tx, rx) = mpsc::channel(2);
+        let task = tokio::spawn(display_task(rx, disp));
         Self {
-            display: Arc::new(Mutex::new(w)),
+            display_channel: tx,
+            display_task: Arc::new(task),
         }
     }
 }
 
+
+#[derive(Debug)]
+pub struct DisplaySetCommand {
+    img: Box<EInkImage>,
+}
+#[instrument(skip_all)]
+pub async fn display_task(
+    mut rx: Receiver<DisplaySetCommand>,
+    mut display: Box<dyn EInkPanel + Send>,
+) {
+    while let Some(cmd) = rx.recv().await {
+        info!("Got a display set command");
+        let raw_buf = cmd.img.into_display_buffer();
+        if let Err(e) = display.display(&raw_buf) {
+            error!("Error displaying command {e}");
+        }
+        info!("Done setting display");
+    }
+}
+
 // Make our own error that wraps `anyhow::Error`.
 struct AppError(anyhow::Error);
 
@@ -58,6 +88,7 @@ pub fn router() -> Router<Context> {
     Router::new().route("/setimage", post(set_image))
 }
 
+#[instrument(skip(ctx))]
 async fn set_image(
     State(ctx): State<Context>,
     mut parts: Multipart,
@@ -65,13 +96,21 @@ async fn set_image(
     while let Some(field) = parts.next_field().await? {
         let name = field.name().expect("fields always have names").to_string();
         let data = field.bytes().await?;
-        println!("Length of `{}` is {} bytes", name, data.len());
+        debug!("Length of `{}` is {} bytes", name, data.len());
         if &name == "image" {
             let reader = ImageReader::new(Cursor::new(data))
                 .with_guessed_format()
                 .expect("Cursor io never fails");
-            println!("Guessed format: {:?}", reader.format());
-            let _image = reader.decode()?;
+            debug!("Guessed format: {:?}", reader.format());
+
+            let image = reader.decode()?;
+            let mut buf = EInkImage::new(800, 480);
+            let dither = ErrorDiffusionDither::new(DiffusionMatrix::Atkinson);
+            dither.dither(&image.into(), &mut buf);
+            let cmd = DisplaySetCommand {
+                img: Box::new(buf),
+            };
+            ctx.display_channel.send_timeout(cmd, Duration::from_secs(10)).await?;
         }
     }
     Ok(())

src/display.rs

@@ -2,8 +2,8 @@ use epd_waveshare::{epd7in3f::Epd7in3f, prelude::WaveshareDisplay};
 use linux_embedded_hal::spidev::SpiModeFlags;
 use linux_embedded_hal::spidev::SpidevOptions;
 use linux_embedded_hal::{CdevPin, Delay, SpidevDevice};
-use tracing::debug_span;
-use tracing::{info, instrument, error, warn, debug};
+use tracing::instrument;
+use tracing::{debug, debug_span, warn};
 
 use anyhow::Result;
 use linux_embedded_hal::gpio_cdev::{Chip, LineRequestFlags};
@@ -12,7 +12,6 @@ pub trait EInkPanel {
     fn display(&mut self, buf: &[u8]) -> Result<()>;
 }
 
-
 pub struct Wrapper {
     spi: SpidevDevice,
     gpiochip: Chip,
@@ -64,9 +63,8 @@ impl Wrapper {
 }
 
 impl EInkPanel for Wrapper {
+    #[instrument(skip_all)]
     fn display(&mut self, buf: &[u8]) -> Result<()> {
-        let span = debug_span!("display");
-        let _enter = span.enter();
         self.panel
             .update_and_display_frame(&mut self.spi, buf, &mut self.delay)?;
         debug!("Finished updating frame");
@@ -78,8 +76,9 @@ impl EInkPanel for Wrapper {
 
 pub struct FakeEInk();
 impl EInkPanel for FakeEInk {
-    fn display(&mut self, buf: &[u8]) -> Result<()> {
+    fn display(&mut self, _buf: &[u8]) -> Result<()> {
         // Do nothing.
+        warn!("Fake display was called");
         Ok(())
     }
 }

src/errors.rs

@@ -1 +1 @@
-use thiserror;
+

src/imageproc.rs

@@ -1,5 +1,5 @@
 use image::RgbImage;
-use tracing::{info, debug, instrument};
+use tracing::instrument;
 
 use image::Rgb as imgRgb;
 use palette::color_difference::Ciede2000;

src/main.rs

@@ -5,6 +5,7 @@ pub mod imageproc;
 
 use crate::display::{EInkPanel, FakeEInk, Wrapper};
 use crate::imageproc::{DiffusionMatrix, Ditherer, EInkImage, ErrorDiffusionDither};
+use tracing::info;
 use clap::{Parser, Subcommand};
 use image::RgbImage;
 
@@ -50,11 +51,13 @@ async fn main() -> anyhow::Result<()> {
     }
 
     if matches!(cli.command, Command::Serve) {
-        let display = FakeEInk {};
+        let display = Wrapper::new()?;
+
         let ctx = api::Context::new(Box::new(display));
 
         let app = api::router().with_state(ctx);
         let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await?;
+        info!("Listening on 0.0.0.0:3000");
         axum::serve(listener, app).await?;
     }
 

test.hurl

@@ -1,3 +1,3 @@
-POST http://localhost:3000/setimage
+POST http://192.168.0.185:3000/setimage
 [MultipartFormData]
 image: file,image.png;