Added first bit of Motoko example

motoko/query_stats/dfx.json

@@ -0,0 +1,16 @@
+{
+  "canisters": {
+    "query_stats": {
+      "main": "src/query_stats_backend/main.mo",
+      "type": "motoko"
+    }
+  },
+  "defaults": {
+    "build": {
+      "args": "",
+      "packtool": ""
+    }
+  },
+  "output_env_file": ".env",
+  "version": 1
+}

motoko/query_stats/src/query_stats_backend/main.mo

@@ -0,0 +1,28 @@
+import Nat "mo:base/Nat";
+import Time "mo:base/Time";
+import Principal "mo:base/Principal";
+
+actor QueryStats {
+
+  let IC = actor "aaaaa-aa" : actor {
+    canister_status : { canister_id : Principal } -> async {
+      query_stats : {
+        num_calls_total : Nat;
+        num_instructions_total : Nat;
+        request_payload_bytes_total : Nat;
+        response_payload_bytes_total : Nat;
+      };
+    };
+  };
+
+  public query func load() : async Int {
+    return Time.now();
+  };
+
+  public func get_current_query_stats_as_string() : async Text {
+    let stats = await IC.canister_status({
+      canister_id = Principal.fromActor(QueryStats);
+    });
+    return "Number of calls: " # Nat.toText(stats.query_stats.num_calls_total) # " - Number of instructions: " # Nat.toText(stats.query_stats.num_instructions_total) # " - Request payload bytes: " # Nat.toText(stats.query_stats.request_payload_bytes_total) # " - Response payload bytes: " # Nat.toText(stats.query_stats.response_payload_bytes_total);
+  };
+};

rust/query-stats/src/lib.rs

@@ -11,7 +11,6 @@ const TIMER_PERIOD_IN_SECS: u64 = 5;
 const QUERY_STATS_PURGE_AFTER_SECS: u64 = 60 * 60 * 24; // 24h, has to be much larger than query stats epoch
 const QUERY_STATS_RATE_FOR_LAST_SECS: u64 = 60 * 60; // 1h, has to be larger than query stats epoch
 
-// Unfortunately, we need to redefine this type, since the members are not public.
 #[derive(CandidType, Debug)]
 pub struct QueryStatRates {
     calls_rate: f32,