rename batch_handler to handler

meilisearch-lib/src/tasks/handlers/snapshot_handler.rs

@@ -0,0 +1,31 @@
+use crate::tasks::batch::{Batch, BatchContent};
+use crate::tasks::BatchHandler;
+
+pub struct SnapshotHandler;
+
+#[async_trait::async_trait]
+impl BatchHandler for SnapshotHandler {
+    fn accept(&self, batch: &Batch) -> bool {
+        match batch.content {
+            BatchContent::Snapshot(_) => true,
+            _ => false,
+        }
+    }
+
+    async fn process_batch(&self, batch: Batch) -> Batch {
+        match batch.content {
+            BatchContent::Snapshot(job) => {
+                if let Err(e) = job.run().await {
+                    log::error!("snapshot error: {e}");
+                }
+            }
+            _ => unreachable!(),
+        }
+
+        Batch::empty()
+    }
+
+    async fn finish(&self, _: &Batch) {
+        ()
+    }
+}