From 7dacc3086296089ce2cd57281f23e49c1e393406 Mon Sep 17 00:00:00 2001
From: Stephen Shelton <steve@brewcraft.org>
Date: Tue, 17 Mar 2020 14:21:38 -0600
Subject: [PATCH] Conveience and clarity around config definiton maps

---
 llarp/config/definition.cpp | 33 +++++++++++++++++++++++----------
 llarp/config/definition.hpp |  9 +++++++--
 2 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/llarp/config/definition.cpp b/llarp/config/definition.cpp
index 5e45dee6c..d1b8eb59a 100644
--- a/llarp/config/definition.cpp
+++ b/llarp/config/definition.cpp
@@ -5,6 +5,25 @@
 namespace llarp
 {
 
+/// utility functions for visiting each section/definition
+///
+using SectionVisitor = std::function<void(const std::string&, const DefinitionMap&)>;
+void visitSections(const SectionMap& sections, SectionVisitor visitor)
+{
+  for (const auto& pair : sections)
+  {
+    visitor(pair.first, pair.second);
+  }
+};
+using DefVisitor = std::function<void(const std::string&, const ConfigDefinition_ptr&)>;
+void visitDefinitions(const DefinitionMap& defs, DefVisitor visitor)
+{
+  for (const auto& pair : defs)
+  {
+    visitor(pair.first, pair.second);
+  }
+};
+
 ConfigDefinitionBase::ConfigDefinitionBase(std::string section_,
                                            std::string name_,
                                            bool required_,
@@ -63,14 +82,8 @@ Configuration::lookupDefinitionOrThrow(string_view section, string_view name)
 void
 Configuration::validate()
 {
-  for (const auto& pair : m_definitions)
-  {
-    const std::string& section = pair.first;
-
-    const auto& sectionDefinitions = pair.second;
-    for (const auto& defPair : sectionDefinitions)
-    {
-      const auto& def = defPair.second;
+  visitSections(m_definitions, [&](const std::string& section, const DefinitionMap& defs) {
+    visitDefinitions(defs, [&](const std::string&, const ConfigDefinition_ptr& def) {
       if (def->required and def->numFound < 1)
       {
         throw std::invalid_argument(stringify(
@@ -79,8 +92,8 @@ Configuration::validate()
 
       // should be handled earlier in ConfigDefinition::parseValue()
       assert(def->numFound == 1 or def->multiValued);
-    }
-  }
+    });
+  });
 }
 
 std::string
diff --git a/llarp/config/definition.hpp b/llarp/config/definition.hpp
index 4d6351159..d765a16c3 100644
--- a/llarp/config/definition.hpp
+++ b/llarp/config/definition.hpp
@@ -119,12 +119,17 @@ namespace llarp
 
   using ConfigDefinition_ptr = std::unique_ptr<ConfigDefinitionBase>;
 
+  // map of k:v pairs
+  using DefinitionMap = std::unordered_map<std::string, ConfigDefinition_ptr>;
+
+  // map of section-name to map-of-definitions
+  using SectionMap = std::unordered_map<std::string, DefinitionMap>;
+
   /// A configuration holds an ordered set of ConfigDefinitions defining the allowable values and
   /// their constraints and an optional set defining overrides of those values (e.g. the results
   /// of a parsed config file).
   struct Configuration {
-    // the first std::string template parameter is the section
-    std::unordered_map<std::string, std::unordered_map<std::string, ConfigDefinition_ptr>> m_definitions;
+    SectionMap m_definitions;
 
     Configuration&
     addDefinition(ConfigDefinition_ptr def);