expose args and exit_code in API

tools/server/README.md

@@ -1455,19 +1455,23 @@ The `status` object can be:
 
 ```json
 "status": {
-  "value": "loading"
+  "value": "loading",
+  "args": ["llama-server", "-ctx", "4096"]
 }
 ```
 
 ```json
 "status": {
-  "value": "failed"
+  "value": "failed",
+  "args": ["llama-server", "-ctx", "4096"],
+  "exit_code": 1
 }
 ```
 
 ```json
 "status": {
-  "value": "loaded"
+  "value": "loaded",
+  "args": ["llama-server", "-ctx", "4096"]
 }
 ```
 

tools/server/server-models.cpp

@@ -368,11 +368,11 @@ void server_models::load(const std::string & name) {
         std::vector<std::string> child_env = base_env; // copy
         child_env.push_back("LLAMA_SERVER_ROUTER_PORT=" + std::to_string(base_params.port));
 
-        // TODO: add logging
         SRV_INF("%s", "spawning server instance with args:\n");
         for (const auto & arg : child_args) {
             SRV_INF("  %s\n", arg.c_str());
         }
+        inst.meta.args = child_args; // save for debugging
 
         std::vector<char *> argv = to_char_ptr_array(child_args);
         std::vector<char *> envp = to_char_ptr_array(child_env);
@@ -405,7 +405,9 @@ void server_models::load(const std::string & name) {
             std::lock_guard<std::mutex> lk(mutex);
             auto it = mapping.find(name);
             if (it != mapping.end()) {
-                it->second.meta.status = exit_code == 0
+                auto & meta = it->second.meta;
+                meta.exit_code = exit_code;
+                meta.status    = exit_code == 0
                                     ? SERVER_MODEL_STATUS_UNLOADED
                                     : SERVER_MODEL_STATUS_FAILED;
             }

tools/server/server-models.h

@@ -58,7 +58,9 @@ struct server_model_meta {
     bool in_cache = false; // if true, use -hf; use -m otherwise
     int port = 0;
     server_model_status status = SERVER_MODEL_STATUS_UNLOADED;
-    int64_t last_used = 0;
+    int64_t last_used = 0; // for LRU unloading
+    std::vector<std::string> args; // additional args passed to the model instance (used for debugging)
+    int exit_code = 0; // exit code of the model instance process (only valid if status == FAILED)
 
     bool is_active() const {
         return status == SERVER_MODEL_STATUS_LOADED || status == SERVER_MODEL_STATUS_LOADING;

tools/server/server.cpp

@@ -5160,7 +5160,7 @@ public:
         std::string name = json_value(body, "model", std::string());
         auto model = models->get_meta(name);
         if (!model.has_value()) {
-            res->error(format_error_response("model is not found", ERROR_TYPE_INVALID_REQUEST));
+            res->error(format_error_response("model is not found", ERROR_TYPE_NOT_FOUND));
             return res;
         }
         if (model->status == SERVER_MODEL_STATUS_LOADED) {
@@ -5188,15 +5188,20 @@ public:
         json models_json = json::array();
         auto all_models = models->get_all_meta();
         for (const auto & model : all_models) {
+            json status {
+                {"value", server_model_status_to_string(model.status)},
+                {"args",  model.args},
+            };
+            if (model.status == SERVER_MODEL_STATUS_FAILED) {
+                status["exit_code"] = model.exit_code;
+            }
             models_json.push_back(json {
                 {"name",     model.name},
                 {"id",       model.name},
                 {"in_cache", model.in_cache},
                 {"path",     model.path},
+                {"status",   status},
                 // TODO: other fields...
-                {"status", {
-                    {"value", server_model_status_to_string(model.status)}
-                }},
             });
         }
         res->ok({{"data", models_json}});