VOM: Additions to allow uses to UT applications that use VOM

- find object by key
- compare objects

Change-Id: I36ec8612be9482bcef7ceced2a59f7403f77b3e8
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
diff --git a/src/vpp-api/vom/interface.hpp b/src/vpp-api/vom/interface.hpp
index 76ecf8a..8cba2fa 100644
--- a/src/vpp-api/vom/interface.hpp
+++ b/src/vpp-api/vom/interface.hpp
@@ -44,7 +44,7 @@
   /**
    * The key for interface's key
    */
-  typedef std::string key_type;
+  typedef std::string key_t;
 
   /**
    * The iterator type
@@ -207,7 +207,7 @@
   /**
    * Return the interface type
    */
-  const key_type& key() const;
+  const key_t& key() const;
 
   /**
    * Return the L2 Address
@@ -225,6 +225,11 @@
   void set(const oper_state_t& state);
 
   /**
+   * Comparison operator - only used for UT
+   */
+  virtual bool operator==(const interface& i) const;
+
+  /**
    * A base class for interface Create commands
    */
   template <typename MSG>
@@ -400,21 +405,14 @@
   };
 
   /**
-   * The the singular instance of the interface in the object_base-Model
-   */
-  static std::shared_ptr<interface> find(const interface& temp);
-
-  /**
-   * The the singular instance of the interface in the object_base-Model
-   * by handle
+   * The the singular instance of the interface in the DB by handle
    */
   static std::shared_ptr<interface> find(const handle_t& h);
 
   /**
-   * The the singular instance of the interface in the object_base-Model
-   * by name
+   * The the singular instance of the interface in the DB by key
    */
-  static std::shared_ptr<interface> find(const std::string& s);
+  static std::shared_ptr<interface> find(const key_t& k);
 
   /**
    * Dump all interfaces into the stream provided
@@ -472,12 +470,12 @@
   /**
    * A map of all interfaces key against the interface's name
    */
-  static singular_db<const std::string, interface> m_db;
+  static singular_db<key_t, interface> m_db;
 
   /**
    * Add an interface to the DB keyed on handle
    */
-  static void add(const std::string& name, const HW::item<handle_t>& item);
+  static void add(const key_t& name, const HW::item<handle_t>& item);
 
   /**
    * remove an interface from the DB keyed on handle
@@ -540,7 +538,7 @@
   /**
    * It's the singular_db class that calls replay()
    */
-  friend class singular_db<const std::string, interface>;
+  friend class singular_db<key_t, interface>;
 
   /**
    * The interfaces name