Changed decode function signature

include/jwt/detail/meta.hpp

@@ -27,6 +27,11 @@ using void_t = typename make_void<T...>::type;
  */
 struct empty_type {};
 
+/**
+ * A type list.
+ */
+template <typename... T> struct list{};
+
 
 /**
  */
@@ -118,6 +123,43 @@ struct is_parameter_concept<T,
 
 /**
  */
+/*
+template <typename T, typename=void>
+struct is_sequence_concept: std::false_type
+{
+};
+
+template <typename T>
+struct is_sequence_concept<>: std::true_type
+{
+};
+*/
+
+/**
+ * Find if a type is present in the typelist.
+ * Eg: has_type<int, list<int, char, float>>{} == true
+ *     has_type<long, list<int, char, float>>{} == false
+ */
+template <typename F, typename T> struct has_type;
+
+template <typename F>
+struct has_type<F, list<>>: std::false_type
+{
+};
+
+template <typename F, typename... T>
+struct has_type<F, list<F, T...>>: std::true_type
+{
+};
+
+template <typename F, typename H, typename... T>
+struct has_type<F, list<H,T...>>: has_type<F, list<T...>>
+{
+};
+
+/**
+ * A pack of bools for the bool trick.
+ */
 template <bool... V>
 struct bool_pack {};
 

include/jwt/impl/jwt.ipp

@@ -351,26 +351,69 @@ jwt_object::three_parts(const string_view enc_str)
 
 //====================================================================
 
-jwt_object jwt_decode(const string_view encoded_str, const string_view key, bool validate)
+namespace { // Anonymous namespace
+
+template <typename DecodeParams, typename... Rest>
+void set_decode_params(DecodeParams& dparams, params::detail::leeway_param l, Rest&&... args)
 {
-  //TODO: implement error_code
-  jwt_object jobj;
+  dparams.leeway = l.get();
+  set_decode_params(dparams, std::forward<Rest>(args)...);
+  return;
+}
 
-  auto parts = jwt_object::three_parts(encoded_str);
+template <typename DecodeParams, typename... Rest>
+void set_decode_params(DecodeParams& dparams, params::detail::verify_param v, Rest&&... args)
+{
+  dparams.verify = v.get();
+  set_decode_params(dparams, std::forward<Rest>(args)...);
+  return;
+}
 
+template <typename DecodeParams>
+void set_decode_params(DecodeParams& dparams)
+{
+  return;
+}
+
+} // END anonymous namespace
+
+template <typename SequenceT, typename... Args>
+jwt_object decode(const string_view enc_str,
+                  const string_view key,
+                  const params::detail::algorithms_param<SequenceT>& algos,
+                  Args&&... args)
+{
+  if (algos.get().size() == 0) {
+    throw DecodeError("Algorithms list cannot be empty");
+  }
+
+  struct decode_params
+  {
+    /// Verify parameter. Defaulted to true.
+    bool verify = true;
+    /// Leeway parameter. Defaulted to zero seconds.
+    uint32_t leeway = 0;
+  };
+
+  decode_params dparams{};
+  set_decode_params(dparams, std::forward<Args>(args)...);
+
+  jwt_object obj;
+
+  auto parts = jwt_object::three_parts(enc_str);
   //throws decode error
-  jobj.header(jwt_header{parts[0]});
+  obj.header(jwt_header{parts[0]});
   //throws decode error
-  jobj.payload(jwt_payload{parts[1]});
+  obj.payload(jwt_payload{parts[1]});
 
   jwt_signature jsign{key};
  
-  //length of the encoded header and payload only.
-  //Addition of '1' to account for the '.' character.
+  // Length of the encoded header and payload only.
+  // Addition of '1' to account for the '.' character.
   auto l = parts[0].length() + 1 + parts[1].length();
-  auto res = jsign.verify(jobj.header(), encoded_str.substr(0, l), parts[2]);
+  auto res = jsign.verify(obj.header(), enc_str.substr(0, l), parts[2]);
 
-  return jobj;
+  return obj; 
 }
 
 } // END namespace jwt

include/jwt/jwt.hpp

@@ -629,8 +629,11 @@ jwt_object jwt_decode(const string_view encoded_str, const string_view key, bool
 
 /**
  */
-template <typename... Args>
-jwt_object decode(const string_view enc_str, const string_view key, Args&&... args);
+template <typename SequenceT, typename... Args>
+jwt_object decode(const string_view enc_str, 
+                  const string_view key, 
+                  const params::detail::algorithms_param<SequenceT>& algos, 
+                  Args&&... args);
 
 
 } // END namespace jwt

include/jwt/parameters.hpp

@@ -2,6 +2,7 @@
 #define CPP_JWT_PARAMETERS_HPP
 
 #include <map>
+#include <vector>
 #include <utility>
 #include <unordered_map>
 
@@ -146,6 +147,7 @@ struct leeway_param
 
 // Useful typedef
 using param_init_list_t = std::initializer_list<std::pair<jwt::string_view, jwt::string_view>>;
+using param_seq_list_t  = std::initializer_list<jwt::string_view>;
 
 
 /**
@@ -238,6 +240,26 @@ leeway(uint32_t l)
   return { l };
 }
 
+/**
+ */
+detail::algorithms_param<std::vector<std::string>>
+algorithms(const param_seq_list_t& seq)
+{
+  std::vector<std::string> vec;
+  vec.reserve(seq.size());
+
+  for (const auto& e: seq) { vec.emplace_back(e.data(), e.length()); }
+
+  return { std::move(vec) };
+}
+
+template <typename SequenceConcept>
+detail::algorithms_param<SequenceConcept>
+algorithms(SequenceConcept&& sc)
+{
+  return { std::forward<SequenceConcept>(sc) };
+}
+
 } // END namespace params
 } // END namespace jwt
 

include/jwt/test/test_jwt_object.cc

@@ -44,7 +44,7 @@ void basic_jwt_object_test()
   obj3.secret("secret");
   obj3.header().algo("hs256");
 
-  auto dec_obj = jwt::jwt_decode(obj3.signature(), "secret");
+  auto dec_obj = jwt::decode(obj3.signature(), "secret", algorithms({"hs256"}));
 }
 
 void jwt_object_pem_test()