Move router to pile-dataset

crates/pile-dataset/src/serve/field.rs

@@ -0,0 +1,90 @@
+use axum::{
+	Json,
+	extract::{Query, State},
+	http::{StatusCode, header},
+	response::{IntoResponse, Response},
+};
+use pile_config::{Label, objectpath::ObjectPath};
+use serde::Deserialize;
+use std::sync::Arc;
+use tracing::debug;
+use utoipa::ToSchema;
+
+use crate::{Datasets, PileValue, extract::MetaExtractor};
+
+#[derive(Deserialize, ToSchema)]
+pub struct FieldQuery {
+	source: String,
+	key: String,
+	path: String,
+}
+
+/// Extract a specific field from an item's metadata
+#[utoipa::path(
+	get,
+	path = "/field",
+	params(
+		("source" = String, Query, description = "Source label"),
+		("key" = String, Query, description = "Item key"),
+		("path" = String, Query, description = "Object path (e.g. $.flac.title)"),
+	),
+	responses(
+		(status = 200, description = "Field value as JSON"),
+		(status = 400, description = "Invalid source label or path"),
+		(status = 404, description = "Item or field not found"),
+		(status = 500, description = "Internal server error"),
+	)
+)]
+pub async fn get_field(
+	State(state): State<Arc<Datasets>>,
+	Query(params): Query<FieldQuery>,
+) -> Response {
+	debug!(
+		message = "Serving /field",
+		source = params.source,
+		key = params.key,
+		path = params.path,
+	);
+
+	let label = match Label::try_from(params.source) {
+		Ok(l) => l,
+		Err(e) => return (StatusCode::BAD_REQUEST, format!("{e:?}")).into_response(),
+	};
+
+	let path: ObjectPath = match params.path.parse() {
+		Ok(p) => p,
+		Err(e) => return (StatusCode::BAD_REQUEST, format!("{e:?}")).into_response(),
+	};
+
+	let Some(item) = state.get(&label, &params.key).await else {
+		return StatusCode::NOT_FOUND.into_response();
+	};
+
+	let extractor = MetaExtractor::new(&item);
+	let root: PileValue<'_> = PileValue::Extractor(Arc::new(extractor));
+
+	let value = match root.query(&path).await {
+		Ok(Some(v)) => v,
+		Ok(None) => return StatusCode::NOT_FOUND.into_response(),
+		Err(e) => return (StatusCode::INTERNAL_SERVER_ERROR, format!("{e:?}")).into_response(),
+	};
+
+	match value {
+		PileValue::String(s) => (
+			StatusCode::OK,
+			[(header::CONTENT_TYPE, "text/plain")],
+			s.to_string(),
+		)
+			.into_response(),
+		PileValue::Blob { mime, bytes } => (
+			StatusCode::OK,
+			[(header::CONTENT_TYPE, mime.to_string())],
+			bytes.as_ref().clone(),
+		)
+			.into_response(),
+		_ => match value.to_json().await {
+			Ok(json) => (StatusCode::OK, Json(json)).into_response(),
+			Err(e) => (StatusCode::INTERNAL_SERVER_ERROR, format!("{e:?}")).into_response(),
+		},
+	}
+}