feat(rag): add claw-rag-service

Adds claw-rag-service for repository indexing and semantic search.

rust/crates/claw-rag-service/src/lib.rs

@@ -0,0 +1,111 @@
+//! Workspace RAG: ingest files → `SQLite` + embeddings, query via cosine similarity (linear scan MVP).
+#![forbid(unsafe_code)]
+
+mod chunk;
+mod db;
+mod embed;
+mod ingest;
+#[cfg(feature = "qdrant-index")]
+mod qdrant_index;
+mod search;
+
+pub use db::{chunk_count, open_db};
+pub use embed::EmbedConfig;
+pub use ingest::{run_ingest, IngestStats};
+pub use search::query_index;
+
+use serde::{Deserialize, Serialize};
+
+/// One retrieved chunk for the model or UI.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RagHit {
+    pub path: String,
+    pub snippet: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub score: Option<f32>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct QueryRequest {
+    pub query: String,
+    #[serde(default = "default_top_k")]
+    pub top_k: u32,
+}
+
+fn default_top_k() -> u32 {
+    8
+}
+
+#[derive(Debug, Clone, Serialize)]
+pub struct QueryResponse {
+    pub hits: Vec<RagHit>,
+    /// `0-stub` (legacy), `1-sqlite`, `1-sqlite-empty`, `1-sqlite-no-db`
+    pub phase: &'static str,
+}
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use reqwest::Client;
+    use tempfile::tempdir;
+
+    use super::*;
+
+    #[tokio::test]
+    async fn query_missing_db_reports_phase() {
+        let client = Client::new();
+        let cfg = EmbedConfig {
+            api_key: "x".into(),
+            base_url: "mock://".into(),
+            model: "m".into(),
+        };
+        let r = query_index(
+            Path::new("/no/such/claw_rag.sqlite"),
+            &client,
+            &cfg,
+            &QueryRequest {
+                query: "hello".into(),
+                top_k: 3,
+            },
+        )
+        .await
+        .unwrap();
+        assert_eq!(r.phase, "1-sqlite-no-db");
+    }
+
+    #[tokio::test]
+    async fn ingest_and_query_roundtrip_mock() {
+        std::env::set_var("CLAW_RAG_MOCK_PROVIDERS", "1");
+        let dir = tempdir().unwrap();
+        let ws1 = dir.path().join("ws1");
+        let ws2 = dir.path().join("ws2");
+        std::fs::create_dir_all(&ws1).unwrap();
+        std::fs::create_dir_all(&ws2).unwrap();
+        std::fs::write(ws1.join("note.md"), "hello RAG service test content").unwrap();
+        std::fs::write(ws2.join("docs.md"), "secondary repo doc about embeddings").unwrap();
+        let db = dir.path().join("idx.sqlite");
+        let client = Client::new();
+        let cfg = EmbedConfig::mock_from_env().expect("mock");
+        let st = run_ingest(&[ws1.clone(), ws2.clone()], &db, &cfg, &client)
+            .await
+            .unwrap();
+        assert!(st.embeddings_written >= 1);
+
+        let r = query_index(
+            &db,
+            &client,
+            &cfg,
+            &QueryRequest {
+                query: "RAG service".into(),
+                top_k: 4,
+            },
+        )
+        .await
+        .unwrap();
+        assert_eq!(r.phase, "1-sqlite");
+        assert!(!r.hits.is_empty());
+        assert!(r.hits.iter().all(|h| h.path.contains(':')));
+        std::env::remove_var("CLAW_RAG_MOCK_PROVIDERS");
+    }
+}