Add `/gov/kv/endpoints` endpoint to access JS endpoint metadata (#5068)

doc/schemas/gov_openapi.json

@@ -76,6 +76,39 @@
         ],
         "type": "string"
       },
+      "EndpointKey": {
+        "properties": {
+          "uri_path": {
+            "$ref": "#/components/schemas/string"
+          },
+          "verb": {
+            "$ref": "#/components/schemas/HttpMethod"
+          }
+        },
+        "required": [
+          "uri_path",
+          "verb"
+        ],
+        "type": "object"
+      },
+      "EndpointKey_to_EndpointProperties": {
+        "items": {
+          "items": {
+            "oneOf": [
+              {
+                "$ref": "#/components/schemas/EndpointKey"
+              },
+              {
+                "$ref": "#/components/schemas/EndpointProperties"
+              }
+            ]
+          },
+          "maxItems": 2,
+          "minItems": 2,
+          "type": "array"
+        },
+        "type": "array"
+      },
       "EndpointMetrics": {
         "properties": {
           "metrics": {
@@ -124,6 +157,36 @@
         },
         "type": "array"
       },
+      "EndpointProperties": {
+        "properties": {
+          "authn_policies": {
+            "$ref": "#/components/schemas/string_array"
+          },
+          "forwarding_required": {
+            "$ref": "#/components/schemas/ForwardingRequired"
+          },
+          "js_function": {
+            "$ref": "#/components/schemas/string"
+          },
+          "js_module": {
+            "$ref": "#/components/schemas/string"
+          },
+          "mode": {
+            "$ref": "#/components/schemas/Mode"
+          },
+          "openapi": {
+            "$ref": "#/components/schemas/json"
+          },
+          "openapi_hidden": {
+            "$ref": "#/components/schemas/boolean"
+          }
+        },
+        "required": [
+          "forwarding_required",
+          "authn_policies"
+        ],
+        "type": "object"
+      },
       "Failure": {
         "properties": {
           "reason": {
@@ -138,6 +201,14 @@
         ],
         "type": "object"
       },
+      "ForwardingRequired": {
+        "enum": [
+          "sometimes",
+          "always",
+          "never"
+        ],
+        "type": "string"
+      },
       "FullMemberDetails": {
         "properties": {
           "cert": {
@@ -265,6 +336,9 @@
         ],
         "type": "object"
       },
+      "HttpMethod": {
+        "type": "string"
+      },
       "JSRuntimeOptions": {
         "properties": {
           "max_execution_time_ms": {
@@ -444,6 +518,14 @@
         ],
         "type": "string"
       },
+      "Mode": {
+        "enum": [
+          "readwrite",
+          "readonly",
+          "historical"
+        ],
+        "type": "string"
+      },
       "NodeId_to_NodeInfo": {
         "additionalProperties": {
           "$ref": "#/components/schemas/NodeInfo"
@@ -1131,6 +1213,12 @@
       "string": {
         "type": "string"
       },
+      "string_array": {
+        "items": {
+          "$ref": "#/components/schemas/string"
+        },
+        "type": "array"
+      },
       "string_to_JwtIssuerMetadata": {
         "additionalProperties": {
           "$ref": "#/components/schemas/JwtIssuerMetadata"
@@ -1487,6 +1575,28 @@
         }
       }
     },
+    "/gov/kv/endpoints": {
+      "get": {
+        "responses": {
+          "200": {
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/EndpointKey_to_EndpointProperties"
+                }
+              }
+            },
+            "description": "Default response description"
+          },
+          "default": {
+            "$ref": "#/components/responses/default"
+          }
+        },
+        "x-ccf-forwarding": {
+          "$ref": "#/components/x-ccf-forwarding/sometimes"
+        }
+      }
+    },
     "/gov/kv/history": {
       "get": {
         "responses": {

include/ccf/endpoint.h

@@ -22,6 +22,11 @@ namespace ccf::endpoints
     URI uri_path;
     /// HTTP Verb
     RESTVerb verb = HTTP_POST;
+
+    std::string to_str() const
+    {
+      return fmt::format("{} {}", verb.c_str(), uri_path);
+    }
   };
 
   DECLARE_JSON_TYPE(EndpointKey);

include/ccf/rest_verb.h

@@ -102,4 +102,14 @@ namespace ccf
 
     verb = RESTVerb(s.c_str());
   }
+
+  inline std::string schema_name(const RESTVerb*)
+  {
+    return "HttpMethod";
+  }
+
+  inline void fill_json_schema(nlohmann::json& schema, const RESTVerb*)
+  {
+    schema["type"] = "string";
+  }
 }

src/node/rpc/member_frontend.h

@@ -499,6 +499,12 @@ namespace ccf
               {
                 response_body[k.hex_str()] = v;
               }
+              else if constexpr (std::is_same_v<
+                                   typename T::Key,
+                                   ccf::endpoints::EndpointKey>)
+              {
+                response_body[k.to_str()] = v;
+              }
               else
               {
                 response_body[k] = v;

src/service/network_tables.h

@@ -2,6 +2,7 @@
 // Licensed under the Apache 2.0 License.
 #pragma once
 
+#include "ccf/endpoint.h"
 #include "ccf/service/signed_req.h"
 #include "ccf/service/tables/acme_certificates.h"
 #include "ccf/service/tables/cert_bundles.h"
@@ -143,11 +144,16 @@ namespace ccf
     const ModulesQuickJsVersion modules_quickjs_version = {
       Tables::MODULES_QUICKJS_VERSION};
     const JSEngine js_engine = {Tables::JSENGINE};
+    const endpoints::EndpointsMap js_endpoints = {endpoints::Tables::ENDPOINTS};
 
     inline auto get_all_js_generic_tables() const
     {
       return std::make_tuple(
-        modules, modules_quickjs_bytecode, modules_quickjs_version, js_engine);
+        modules,
+        modules_quickjs_bytecode,
+        modules_quickjs_version,
+        js_engine,
+        js_endpoints);
     }
 
     //