Add a method that decodes path parameters (#4126)

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
 
 - New `GET /node/network/removable_nodes` and `DELETE /node/network/nodes/{node_id}` exposed to allow operator to decide which nodes can be safely shut down after retirement, and clear their state from the Key-Value Store.
+- Added a new method `get_decoded_request_path_params` that returns a map of decoded path parameters (#4126)
 
 ### Fixed
 

include/ccf/rpc_context.h

@@ -72,6 +72,12 @@ namespace ccf
     /// {"name": "bob", "age": "42"}
     virtual const PathParams& get_request_path_params() = 0;
 
+    /// Decodes the path before returning a map of all PathParams.
+    /// For example, if the endpoint was installed at `/foo/{name}/{age}`, and
+    /// for the request path `/foo/bob%3A/42`, this would return the map:
+    /// {"name": "bob:", "age": "42"}
+    virtual const PathParams& get_decoded_request_path_params() = 0;
+
     /// Returns map of all headers found in the request.
     virtual const http::HeaderMap& get_request_headers() const = 0;
 

src/endpoints/endpoint_registry.cpp

@@ -4,6 +4,7 @@
 #include "ccf/endpoint_registry.h"
 
 #include "ccf/common_auth_policies.h"
+#include "http/http_parser.h"
 #include "node/rpc/rpc_context_impl.h"
 
 namespace ccf::endpoints
@@ -279,7 +280,6 @@ namespace ccf::endpoints
     kv::Tx&, ccf::RpcContext& rpc_ctx)
   {
     auto method = rpc_ctx.get_method();
-
     auto endpoints_for_exact_method = fully_qualified_endpoints.find(method);
     if (endpoints_for_exact_method != fully_qualified_endpoints.end())
     {
@@ -318,6 +318,7 @@ namespace ccf::endpoints
                 throw std::logic_error("Unexpected type of RpcContext");
               }
               auto& path_params = ctx_impl->path_params;
+              auto& decoded_path_params = ctx_impl->decoded_path_params;
               for (size_t i = 0;
                    i < endpoint->spec.template_component_names.size();
                    ++i)
@@ -325,7 +326,9 @@ namespace ccf::endpoints
                 const auto& template_name =
                   endpoint->spec.template_component_names[i];
                 const auto& template_value = match[i + 1].str();
+                auto decoded_value = http::url_decode(template_value);
                 path_params[template_name] = template_value;
+                decoded_path_params[template_name] = decoded_value;
               }
             }
 

src/node/rpc/rpc_context_impl.h

@@ -36,6 +36,12 @@ namespace ccf
       return path_params;
     }
 
+    ccf::PathParams decoded_path_params = {};
+    virtual const ccf::PathParams& get_decoded_request_path_params() override
+    {
+      return decoded_path_params;
+    }
+
     bool is_create_request = false;
     bool execute_on_node = false;
 

src/node/rpc/test/frontend_test.cpp

@@ -255,6 +255,23 @@ public:
   }
 };
 
+class TestDecodedTemplatedPaths : public BaseTestFrontend
+{
+public:
+  TestDecodedTemplatedPaths(kv::Store& tables) : BaseTestFrontend(tables)
+  {
+    open();
+
+    auto endpoint = [this](auto& ctx) {
+      nlohmann::json response_body =
+        ctx.rpc_ctx->get_decoded_request_path_params();
+      ctx.rpc_ctx->set_response_body(response_body.dump(2));
+      ctx.rpc_ctx->set_response_status(HTTP_STATUS_OK);
+    };
+    make_endpoint("/{foo}/{bar}/{baz}", HTTP_POST, endpoint).install();
+  }
+};
+
 class TestMemberFrontend : public MemberRpcFrontend
 {
 public:
@@ -1060,7 +1077,7 @@ TEST_CASE("Templated paths")
   TestTemplatedPaths frontend(*network.tables);
 
   {
-    auto request = create_simple_request("/fin/fang/foom");
+    auto request = create_simple_request("/fin%3A/fang/foom");
     const auto serialized_request = request.build_request();
 
     auto rpc_ctx = ccf::make_rpc_context(user_session, serialized_request);
@@ -1068,7 +1085,7 @@ TEST_CASE("Templated paths")
     CHECK(response.status == HTTP_STATUS_OK);
 
     std::map<std::string, std::string> expected_mapping;
-    expected_mapping["foo"] = "fin";
+    expected_mapping["foo"] = "fin%3A";
     expected_mapping["bar"] = "fang";
     expected_mapping["baz"] = "foom";
 
@@ -1098,6 +1115,32 @@ TEST_CASE("Templated paths")
   }
 }
 
+TEST_CASE("Decoded Templated paths")
+{
+  NetworkState network;
+  prepare_callers(network);
+  TestDecodedTemplatedPaths frontend(*network.tables);
+
+  {
+    auto request = create_simple_request("/fin%3A/fang%2F/foom");
+    const auto serialized_request = request.build_request();
+
+    auto rpc_ctx = ccf::make_rpc_context(user_session, serialized_request);
+    auto response = parse_response(frontend.process(rpc_ctx).value());
+    CHECK(response.status == HTTP_STATUS_OK);
+
+    std::map<std::string, std::string> expected_mapping;
+    expected_mapping["foo"] = "fin:";
+    expected_mapping["bar"] = "fang/";
+    expected_mapping["baz"] = "foom";
+
+    const auto response_json = nlohmann::json::parse(response.body);
+    const auto actual_mapping = response_json.get<decltype(expected_mapping)>();
+
+    CHECK(expected_mapping == actual_mapping);
+  }
+}
+
 TEST_CASE("Signed read requests can be executed on backup")
 {
   NetworkState network;