Return JSON-formatted errors

Author: rjgraffham

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "ereadifier"
-version = "0.3.3"
+version = "0.3.4"
 edition = "2024"
 
 [lints.clippy]
@@ -12,6 +12,7 @@ chrono = "0.4"
 futures-util = "0.3"
 image = { version = "0.25", default-features = false, features = ["default-formats"] }
 regex = "1.12"
+serde = { version = "1.0", features = ["derive"] }
 tokio = { version = "1", features = ["full"] }
 warp = { version = "0.4", features = ["multipart", "server"] }
 webp = "0.3"

Cargo.toml

@@ -3,7 +3,6 @@
 Improvements I want to make, in no particular order:
 
 * Add a health check endpoint (and move conversion to an explicit /convert endpoint)
-* Return structured JSON errors
 * Make presets data-driven to ease expanding the list later:
     - TOML file which defines the dimensions and a list of devices for each named preset
     - Server loads TOML file when parsing dimensions

ROADMAP.md

@@ -1,5 +1,6 @@
 use bytes::BufMut;
 use futures_util::StreamExt;
+use serde::Serialize;
 use warp::Filter;
 
 #[derive(Debug)]
@@ -15,6 +16,12 @@ impl warp::reject::Reject for EncodeError {}
 impl warp::reject::Reject for DecodeError {}
 impl warp::reject::Reject for NoInput {}
 
+#[derive(Serialize)]
+struct ErrorDetails {
+    code: u16,
+    message: String,
+}
+
 struct Config {
     dimensions: Option<(u32, u32)>,
     lossy_quality: f32,
@@ -325,7 +332,12 @@ async fn handle_errors(err: warp::Rejection) -> Result<impl warp::Reply, std::co
         message
     );
 
-    Ok::<warp::reply::WithStatus<&str>, _>(warp::reply::with_status(message, code))
+    let json = warp::reply::json(&ErrorDetails {
+        code: code.as_u16(),
+        message: message.into(),
+    });
+
+    Ok(warp::reply::with_status(json, code))
 }
 
 #[tokio::main]