Extractor rewrite

crates/pile-value/src/extract/item/exif.rs

@@ -0,0 +1,96 @@
+use pile_config::Label;
+use std::{
+	collections::HashMap,
+	io::BufReader,
+	sync::{Arc, OnceLock},
+};
+use tracing::trace;
+
+use crate::{
+	extract::traits::ObjectExtractor,
+	value::{Item, PileValue, SyncReadBridge},
+};
+
+pub struct ExifExtractor {
+	item: Item,
+	output: OnceLock<HashMap<Label, PileValue>>,
+}
+
+impl ExifExtractor {
+	pub fn new(item: &Item) -> Self {
+		Self {
+			item: item.clone(),
+			output: OnceLock::new(),
+		}
+	}
+
+	async fn get_inner(&self) -> Result<&HashMap<Label, PileValue>, std::io::Error> {
+		if let Some(x) = self.output.get() {
+			return Ok(x);
+		}
+
+		let reader = SyncReadBridge::new_current(self.item.read().await?);
+		let raw_fields = tokio::task::spawn_blocking(move || {
+			let mut br = BufReader::new(reader);
+			let exif = exif::Reader::new()
+				.read_from_container(&mut br)
+				.map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidData, e.to_string()))?;
+
+			let fields: Vec<(String, String)> = exif
+				.fields()
+				.map(|f| {
+					(
+						f.tag.to_string(),
+						f.display_value().with_unit(&exif).to_string(),
+					)
+				})
+				.collect();
+
+			Ok::<_, std::io::Error>(fields)
+		})
+		.await
+		.map_err(std::io::Error::other)?;
+
+		let raw_fields = match raw_fields {
+			Ok(x) => x,
+			Err(error) => {
+				trace!(message = "Could not process exif", ?error, key = ?self.item.key());
+				return Ok(self.output.get_or_init(HashMap::new));
+			}
+		};
+
+		let mut output: HashMap<Label, PileValue> = HashMap::new();
+
+		for (tag_name, value) in raw_fields {
+			let Some(label) = tag_to_label(&tag_name) else {
+				continue;
+			};
+			// First occurrence wins (PRIMARY IFD comes before THUMBNAIL)
+			output
+				.entry(label)
+				.or_insert_with(|| PileValue::String(Arc::new(value.into())));
+		}
+
+		return Ok(self.output.get_or_init(|| output));
+	}
+}
+
+fn tag_to_label(tag: &str) -> Option<Label> {
+	let sanitized: String = tag
+		.chars()
+		.map(|c| if c == ' ' { '_' } else { c })
+		.filter(|c| Label::VALID_CHARS.contains(*c))
+		.collect();
+	Label::new(sanitized)
+}
+
+#[async_trait::async_trait]
+impl ObjectExtractor for ExifExtractor {
+	async fn field(&self, name: &Label) -> Result<Option<PileValue>, std::io::Error> {
+		Ok(self.get_inner().await?.get(name).cloned())
+	}
+
+	async fn fields(&self) -> Result<Vec<Label>, std::io::Error> {
+		Ok(self.get_inner().await?.keys().cloned().collect())
+	}
+}