[trac736] refactor find_spec_part

src/lib/config/config_data.cc

@@ -21,6 +21,56 @@
 
 using namespace isc::data;
 
+namespace {
+
+// Returns the '_spec' part of a list or map specification
+//
+// \param spec_part the list or map specification (part)
+// \return the value of spec_part's "list_item_spec" or "map_item_spec",
+//         or the original spec_part, if it is not a MapElement or does
+//         not contain "list_item_spec" or "map_item_spec"
+ConstElementPtr findListOrMapSubSpec(ConstElementPtr spec_part) {
+    while (spec_part->getType() == Element::map && 
+           (spec_part->contains("list_item_spec") ||
+            spec_part->contains("map_item_spec"))) {
+        if (spec_part->contains("list_item_spec")) {
+            spec_part = spec_part->get("list_item_spec");
+        } else {
+            spec_part = spec_part->get("map_item_spec");
+        }
+    }
+    return spec_part;
+}
+
+// Returns a specific Element in a given specification ListElement
+//
+// \param spec_part ListElement to find the element in
+// \param id_part the name of the element to find (must match the value
+//                "item_name" in the list item
+// \param id_full the full identifier id_part is a part of, this is
+//                used to better report any errors
+ConstElementPtr findItemInSpecList(ConstElementPtr spec_part,
+                                   const std::string& id_part,
+                                   const std::string& id_full)
+{
+    bool found = false;
+    BOOST_FOREACH(ConstElementPtr list_el, spec_part->listValue()) {
+        if (list_el->getType() == Element::map &&
+            list_el->contains("item_name") &&
+            list_el->get("item_name")->stringValue() == id_part) {
+            spec_part = list_el;
+            found = true;
+        }
+    }
+    if (!found) {
+        isc_throw(isc::config::DataNotFoundError,
+                  id_part + " in " + id_full + " not found");
+    }
+    return (spec_part);
+}
+
+} // anonymous namespace
+
 namespace isc {
 namespace config {
 
@@ -39,7 +89,7 @@ find_spec_part(ConstElementPtr spec, const std::string& identifier) {
     if (!spec) {
         isc_throw(DataNotFoundError, "Empty specification");
     }
-    //std::cout << "in: " << std::endl << spec << std::endl;
+
     ConstElementPtr spec_part = spec;
     if (identifier == "") {
         isc_throw(DataNotFoundError, "Empty identifier");
@@ -52,63 +102,25 @@ find_spec_part(ConstElementPtr spec, const std::string& identifier) {
         // As long as we are not in the 'final' element as specified
         // by the identifier, we want to automatically traverse list
         // and map specifications
-        while (spec_part->getType() == Element::map && 
-               (spec_part->contains("list_item_spec") ||
-                spec_part->contains("map_item_spec"))) {
-            if (spec_part->contains("list_item_spec")) {
-                spec_part = spec_part->get("list_item_spec");
-            } else {
-                spec_part = spec_part->get("map_item_spec");
-            }
-        }
+        spec_part = findListOrMapSubSpec(spec_part);
+
         if (spec_part->getType() == Element::list) {
-            bool found = false;
-            BOOST_FOREACH(ConstElementPtr list_el, spec_part->listValue()) {
-                if (list_el->getType() == Element::map &&
-                    list_el->contains("item_name") &&
-                    list_el->get("item_name")->stringValue() == part) {
-                    spec_part = list_el;
-                    found = true;
-                }
-            }
-            if (!found) {
-                isc_throw(DataNotFoundError, part + " in " + identifier + " not found");
-            }
+            spec_part = findItemInSpecList(spec_part, part, identifier);
         } else {
-            isc_throw(DataNotFoundError, "NOT LIST OF SPEC ITEMS: " + spec_part->str());
+            isc_throw(DataNotFoundError,
+                      "Not a list of spec items: " + spec_part->str());
         }
         id = id.substr(sep + 1);
         sep = id.find("/");
     }
     if (id != "" && id != "/") {
         if (spec_part->getType() == Element::list) {
-            bool found = false;
-            BOOST_FOREACH(ConstElementPtr list_el, spec_part->listValue()) {
-                if (list_el->getType() == Element::map &&
-                    list_el->contains("item_name") &&
-                    list_el->get("item_name")->stringValue() == id) {
-                    spec_part = list_el;
-                    found = true;
-                }
-            }
-            if (!found) {
-                isc_throw(DataNotFoundError, id + " in " + identifier + " not found");
-            }
+            spec_part = findItemInSpecList(spec_part, id, identifier);
         } else if (spec_part->getType() == Element::map) {
             if (spec_part->contains("map_item_spec")) {
-                bool found = false;
-                BOOST_FOREACH(ConstElementPtr list_el,
-                              spec_part->get("map_item_spec")->listValue()) {
-                    if (list_el->getType() == Element::map &&
-                        list_el->contains("item_name") &&
-                        list_el->get("item_name")->stringValue() == id) {
-                        spec_part = list_el;
-                        found = true;
-                    }
-                }
-                if (!found) {
-                    isc_throw(DataNotFoundError, id + " in " + identifier + " not found");
-                }
+                spec_part = findItemInSpecList(
+                                spec_part->get("map_item_spec"),
+                                id, identifier);
             } else {
                 isc_throw(DataNotFoundError, "Element above " + id +
                                              " in " + identifier +