make serializer header not depend on json.hpp (#562)

This fixes the previously broken compilation of ngraph-mxnet which directly utilized serializer.hpp

src/ngraph/serializer.cpp

@@ -75,6 +75,7 @@
 #include "ngraph/ops/tan.hpp"
 #include "ngraph/ops/tanh.hpp"
 #include "ngraph/util.hpp"
+#include "nlohmann/json.hpp"
 
 #ifdef NGRAPH_DISTRIBUTED
 #include "ngraph/ops/allreduce.hpp"
@@ -84,6 +85,21 @@ using namespace ngraph;
 using namespace std;
 using json = nlohmann::json;
 
+template <typename T>
+T get_or_default(nlohmann::json& j, const std::string& key, const T& default_value)
+{
+    T rc;
+    try
+    {
+        rc = j.at(key).get<T>();
+    }
+    catch (...)
+    {
+        rc = default_value;
+    }
+    return rc;
+}
+
 static std::shared_ptr<ngraph::Function>
     read_function(const json&, std::unordered_map<std::string, std::shared_ptr<Function>>&);
 

src/ngraph/serializer.hpp

@@ -21,26 +21,10 @@
 
 #include "ngraph/function.hpp"
 #include "ngraph/node.hpp"
-#include "nlohmann/json.hpp"
 
 namespace ngraph
 {
     std::string serialize(std::shared_ptr<ngraph::Function>, size_t indent = 0);
     std::shared_ptr<ngraph::Function> deserialize(std::istream&);
     std::shared_ptr<ngraph::Function> deserialize(const std::string&);
-
-    template <typename T>
-    T get_or_default(nlohmann::json& j, const std::string& key, const T& default_value)
-    {
-        T rc;
-        try
-        {
-            rc = j.at(key).get<T>();
-        }
-        catch (...)
-        {
-            rc = default_value;
-        }
-        return rc;
-    }
 }

test/serialize.cpp

@@ -30,6 +30,21 @@ using namespace std;
 using namespace ngraph;
 using json = nlohmann::json;
 
+template <typename T>
+T get_or_default(nlohmann::json& j, const std::string& key, const T& default_value)
+{
+    T rc;
+    try
+    {
+        rc = j.at(key).get<T>();
+    }
+    catch (...)
+    {
+        rc = default_value;
+    }
+    return rc;
+}
+
 TEST(serialize, main)
 {
     // First create "f(A,B,C) = (A+B)*C".

test/util/benchmark.cpp

@@ -13,6 +13,9 @@
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
+
+#include <iomanip>
+
 #include "benchmark.hpp"
 #include "ngraph/runtime/backend.hpp"
 #include "ngraph/runtime/call_frame.hpp"