engram/src/server.el

@@ -112,13 +112,14 @@ fn route_scan_nodes(method: String, path: String, body: String) -> String {
 }
 
 // route_scan_edges — bulk export of all edges as a JSON array. Implemented
-// via engram_save → fs_read of the canonical on-disk snapshot, which the
-// runtime keeps in lockstep with the in-memory graph. Live against the
-// running graph, not a stale export.
+// via engram_save → fs_read of a SCRATCH export path. (2026-07-21 self-review:
+// previously this saved over the canonical snapshot.json on every GET — if the
+// process ever booted with a partial/empty store, the first read request
+// clobbered the good snapshot. Read routes must never write the canonical path.)
 fn route_scan_edges(method: String, path: String, body: String) -> String {
     let dir_raw: String = env("ENGRAM_DATA_DIR")
     let dir: String = if str_eq(dir_raw, "") { "/tmp/engram" } else { dir_raw }
-    let snap_path: String = dir + "/snapshot.json"
+    let snap_path: String = dir + "/.scan-export.json"
     engram_save(snap_path)
     let snap: String = fs_read(snap_path)
     if str_eq(snap, "") { return "[]" }
@@ -219,13 +220,33 @@ fn route_health(method: String, path: String, body: String) -> String {
 fn route_sync(method: String, path: String, body: String) -> String {
     let dir_raw: String = env("ENGRAM_DATA_DIR")
     let dir: String = if str_eq(dir_raw, "") { "/tmp/engram" } else { dir_raw }
-    let snap_path: String = dir + "/snapshot.json"
+    // 2026-07-21 self-review: export to a scratch path, never the canonical
+    // snapshot.json — read routes must not be able to clobber the good snapshot.
+    let snap_path: String = dir + "/.sync-export.json"
     engram_save(snap_path)
     let snap: String = fs_read(snap_path)
     if str_eq(snap, "") { return "{\"nodes\":[],\"edges\":[]}" }
     return snap
 }
 
+// route_load_merge — POST /api/load-merge {"path": "..."} — merge a snapshot
+// file into the live store WITHOUT resetting it (engram_load_merge skips nodes
+// already present by id). Added 2026-07-21 self-review to restore the 244 kn-
+// identity Knowledge nodes lost from the snapshot lineage between 05-13 and
+// 07-13. Requires an explicit path: refuses to run without one so it can never
+// be triggered accidentally against a default.
+fn route_load_merge(method: String, path: String, body: String) -> String {
+    let p: String = json_get_string(body, "path")
+    if str_eq(p, "") { return err_json("path is required") }
+    if str_eq(fs_read(p), "") { return err_json("file missing or empty") }
+    let before_n: Int = engram_node_count()
+    let before_e: Int = engram_edge_count()
+    engram_load_merge(p)
+    let added_n: Int = engram_node_count() - before_n
+    let added_e: Int = engram_edge_count() - before_e
+    "{\"ok\":true,\"nodes_added\":" + int_to_str(added_n) + ",\"edges_added\":" + int_to_str(added_e) + ",\"node_count\":" + int_to_str(engram_node_count()) + "}"
+}
+
 // route_emit_ise — write an InternalStateEvent node from the soul daemon.
 //
 // Endpoint: POST /api/neuron/state-events
@@ -422,6 +443,9 @@ fn handle_request(method: String, path: String, body: String) -> String {
     if str_eq(method, "POST") && (str_eq(clean, "/api/load") || str_eq(clean, "/load")) {
         return route_load(method, path, body)
     }
+    if str_eq(method, "POST") && (str_eq(clean, "/api/load-merge") || str_eq(clean, "/load-merge")) {
+        return route_load_merge(method, path, body)
+    }
 
     // Sync — soul daemon periodic pull of non-ISE knowledge into in-process graph
     if str_eq(method, "GET") && str_eq(clean, "/api/sync") {
@@ -443,6 +467,21 @@ let data_dir: String = if str_eq(data_dir_raw, "") { "/tmp/engram" } else { data
 let snapshot_path: String = data_dir + "/snapshot.json"
 engram_load(snapshot_path)
 
+// 2026-07-21 self-review boot guard: if the snapshot file has content but the
+// load produced 0 nodes, something is wrong (corrupt file / parse failure).
+// Preserve the evidence and warn loudly — and since read routes no longer write
+// the canonical path, a bad boot can no longer clobber the good snapshot.
+let boot_snap: String = fs_read(snapshot_path)
+if !str_eq(boot_snap, "") {
+    if engram_node_count() == 0 {
+        println("[engram] WARNING: snapshot.json is non-empty but load produced 0 nodes — preserving copy at snapshot.failed-load.json")
+        fs_write(data_dir + "/snapshot.failed-load.json", boot_snap)
+    } else {
+        // Good load: keep a boot-time backup of the snapshot as loaded.
+        fs_write(data_dir + "/snapshot.boot-backup.json", boot_snap)
+    }
+}
+
 println("[engram] runtime-native graph engine")
 println("[engram] data_dir=" + data_dir)
 println("[engram] node_count=" + int_to_str(engram_node_count()))