Struct Engine 

pub struct Engine {
    pub db: PgPool,
    pub search_index: Arc<RwLock<SearchIndex>>,
    pub parser: Arc<ParserRegistry>,
    pub storage_path: PathBuf,
    /* private fields */
}

The central orchestration layer that ties together Git storage, language parsing, the semantic graph stores, and full-text search.

Internally concurrent: all methods take &self. The SearchIndex is wrapped in an RwLock (write for mutations, read for queries), and per-repo Git operations are serialised via repo_locks.

Fields

db: PgPool

search_index: Arc<RwLock<SearchIndex>>

parser: Arc<ParserRegistry>

storage_path: PathBuf

Implementations

impl Engine

pub fn new(storage_path: PathBuf, db: PgPool) -> Result<Self>

Create a new Engine instance.

Initialises all graph stores from the provided PgPool, creates the ParserRegistry with Rust/TypeScript/Python parsers, and opens (or creates) a Tantivy SearchIndex at storage_path/search_index.

pub fn symbol_store(&self) -> &SymbolStore

Returns a reference to the symbol store for direct DB queries.

pub fn changeset_store(&self) -> &ChangesetStore

Returns a reference to the changeset store.

pub fn pipeline_store(&self) -> &PipelineStore

Returns a reference to the pipeline store.

pub fn workspace_manager(&self) -> &WorkspaceManager

Returns a reference to the workspace manager.

pub fn call_graph_store(&self) -> &CallGraphStore

Returns a reference to the call graph store for direct DB queries.

pub fn dep_store(&self) -> &DependencyStore

Returns a reference to the dependency store for direct DB queries.

pub fn parser(&self) -> &ParserRegistry

Returns a reference to the parser registry.

pub fn repo_lock(&self, repo_id: RepoId) -> Arc<RwLock<()>>

Returns a per-repo lock for serialising Git operations.

Creates a new lock on first access for a given repo_id.

pub fn remove_repo_lock(&self, repo_id: RepoId)

Remove the repo lock entry for a deleted repo.

pub async fn create_repo(&self, name: &str) -> Result<RepoId>

Create a new repository.

Generates a UUID, initialises a Git repository at storage_path/repos/<uuid>, inserts a row into the repositories table, and returns the new RepoId.

pub async fn get_repo(&self, name: &str) -> Result<(RepoId, GitRepository)>

Look up a repository by name.

Returns the RepoId and an opened GitRepository handle.

pub async fn get_repo_by_db_id( &self, repo_id: RepoId, ) -> Result<(RepoId, GitRepository)>

Look up a repository by its UUID.

Returns the RepoId and an opened GitRepository handle.

pub async fn index_repo( &self, repo_id: RepoId, git_repo: &GitRepository, ) -> Result<()>

Perform a full index of a repository.

Walks the working directory (skipping .git), parses every file with a supported extension, and populates the symbol table, type info store, call graph, and full-text search index.

pub async fn update_files( &self, repo_id: RepoId, git_repo: &GitRepository, changed_files: &[PathBuf], ) -> Result<()>

Incrementally re-index a set of changed files.

For each path: deletes old symbols and call edges, re-parses, and upserts the new data.

pub async fn update_files_by_root( &self, repo_id: RepoId, root: &Path, changed_files: &[PathBuf], ) -> Result<()>

Incrementally re-index a set of changed files, given the repository root path directly.

This variant avoids holding a GitRepository reference (which is !Sync) across .await points, making the resulting future Send.

pub async fn query_symbols( &self, repo_id: RepoId, query: &str, max_results: usize, ) -> Result<Vec<Symbol>>

Search for symbols matching a free-text query.

Uses Tantivy full-text search to find candidate SymbolIds, then fetches the full Symbol objects from the database.

pub async fn get_call_graph( &self, _repo_id: RepoId, symbol_id: SymbolId, ) -> Result<(Vec<Symbol>, Vec<Symbol>)>

Retrieve the call graph neighbourhood of a symbol.

Returns (callers, callees) — the full Symbol objects for every direct caller and every direct callee.

pub async fn codebase_summary(&self, repo_id: RepoId) -> Result<CodebaseSummary>

Produce a high-level summary of the indexed codebase.

Queries the symbols table for distinct file extensions (→ languages), distinct file paths (→ total_files), and total row count (→ total_symbols).

impl Engine

pub async fn tool_connect( &self, repo_name: &str, intent: &str, agent_id: &str, session_id: Uuid, changeset_id: Uuid, ) -> Result<ToolConnectResult>

CONNECT — establish an isolated session workspace.

pub async fn tool_context( &self, session_id: Uuid, query: &str, depth: Option<&str>, _include_tests: Option<bool>, _max_tokens: Option<u32>, ) -> Result<ToolContextResult>

CONTEXT — semantic code search through the session workspace.

pub async fn tool_read_file( &self, session_id: Uuid, path: &str, ) -> Result<ToolFileReadResult>

FILE_READ — read a file through the session workspace overlay.

pub async fn tool_write_file( &self, session_id: Uuid, changeset_id: Uuid, path: &str, content: &str, ) -> Result<ToolFileWriteResult>

FILE_WRITE — write a file to the session workspace overlay.

pub async fn tool_submit( &self, _session_id: Uuid, changeset_id: Uuid, _intent: &str, ) -> Result<ToolSubmitResult>

SUBMIT — submit the session’s workspace changes as a changeset.

pub async fn tool_session_status( &self, session_id: Uuid, ) -> Result<ToolStatusResult>

SESSION_STATUS — get the current workspace state.

pub async fn tool_list_files( &self, session_id: Uuid, prefix: Option<&str>, ) -> Result<ToolFileListResult>

LIST_FILES — list files visible in the session workspace.

pub async fn tool_verify_prepare( &self, session_id: Uuid, ) -> Result<(Uuid, String)>

VERIFY — prepare a session’s changeset for verification.

Returns (changeset_id, repo_name) after validating the session, checking the changeset, and updating its status to “verifying”. The actual runner invocation must be done by the caller (since dk-runner depends on dk-engine, not the other way around).

pub async fn tool_verify_finalize( &self, changeset_id: Uuid, passed: bool, ) -> Result<()>

VERIFY — finalize after the runner has completed.

Updates the changeset status to “approved” or “rejected” based on whether all steps passed.

pub async fn tool_merge( &self, session_id: Uuid, message: Option<&str>, ) -> Result<ToolMergeResult>

MERGE — merge the verified changeset into a Git commit.