add query function

src/fd_sfc_cache.erl

@@ -7,6 +7,7 @@
 ]).
 
 -export([
+    query/2,
     new/0, new/1
 ]).
 
@@ -15,6 +16,20 @@
 -type cache() :: #{HttpPath :: binary() := Entry :: fd_sfc_entry:entry()}.
 
 
+-spec query(HttpPath, Cache) -> Result
+    when HttpPath :: binary(),
+         Cache    :: cache(),
+         Result   :: {found, Entry}
+                   | not_found,
+         Entry    :: fd_sfc_entry:entry().
+
+query(HttpPath, Cache) ->
+    case maps:find(HttpPath, Cache) of
+        {ok, Entry} -> {found, Entry};
+        error       -> not_found
+    end.
+
+
 -spec new() -> cache().
 new() -> #{}.