Add MCP servers support on /mcp/ endpoint (#41)

* The plugin now can act as an MCP proxy for multiple MCP servers.
* The behavior is the same as for the rest of the plugin, except that the endpoint to use is /mcp.

---------

Signed-off-by: Julien Barbot <jubarbot@cisco.com>
Co-authored-by: ataldir <ataldir@cisco.com>

Author: jubarbot-cisco

configs/mcp.oas.json

@@ -0,0 +1,109 @@
+{
+  "x-tyk-api-gateway": {
+    "info": {
+      "id": "tyk-mcp-id",
+      "name": "MCP services",
+      "state": {
+        "active": true
+      }
+    },
+    "upstream": {
+      "url": "http://"
+    },
+    "server": {
+      "listenPath": {
+        "value": "/mcp/",
+        "strip": true
+      }
+    },
+    "middleware": {
+      "global": {
+        "pluginConfig": {
+          "data": {
+            "enabled": true,
+            "value": {
+              "mcpServers": {
+                "github": {
+                  "command": "docker",
+                  "args": [
+                    "run",
+                    "-i",
+                    "--rm",
+                    "-e",
+                    "GITHUB_PERSONAL_ACCESS_TOKEN",
+                    "ghcr.io/github/github-mcp-server"
+                  ],
+                  "env": ["GITHUB_PERSONAL_ACCESS_TOKEN=${GITHUB_PERSONAL_ACCESS_TOKEN}"]
+                }
+              }
+            }
+          },
+          "driver": "goplugin"
+        },
+        "postPlugins": [
+          {
+            "enabled": true,
+            "functionName": "ProcessMCPQuery",
+            "path": "middleware/agent-bridge-plugin.so"
+          }
+        ]
+      }
+    }
+  },
+  "openapi": "3.0.1",
+  "info": {
+    "title": "MCP",
+    "description": "Call configured MCP server tools",
+    "version": "0.0.1"
+  },
+  "servers": [
+    {
+      "url": "/"
+    }
+  ],
+  "paths": {
+    "/init": {
+      "post": {
+        "summary": "Initialize MCP servers",
+        "requestBody": {
+          "content": {
+            "text/plain": {
+              "schema": {
+                "type": "string"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "MCP initialization state.",
+            "content": {}
+          }
+        }
+      }
+    },
+    "/": {
+      "post": {
+        "summary": "Call an MCP server from a natural language query",
+        "requestBody": {
+          "content": {
+            "text/plain": {
+              "schema": {
+                "type": "string"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "NLQ Response.",
+            "content": {}
+          }
+        }
+      }
+    }
+  },
+  "components": {}
+}

go.work.sum

@@ -253,6 +253,8 @@ github.com/json-iterator/go v1.1.11/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
 github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51/go.mod h1:CzGEWj7cYgsdH8dAjBGEr58BoE7ScuLd+fwFZ44+/x8=
+github.com/kelindar/search v0.4.0 h1:mj3U26qB6BQJr9/6Q1vHS/I40CQ6Mhb5iJfmfI2e/mY=
+github.com/kelindar/search v0.4.0/go.mod h1:7goLXnzQ6b0vMJr9SKWmABblTrJgPG3rVwp3yz2Lo5Q=
 github.com/klauspost/compress v1.18.0/go.mod h1:2Pp+KzxcywXVXMr50+X0Q/Lsb43OQHYWRCY2AiWywWQ=
 github.com/klauspost/cpuid/v2 v2.2.8/go.mod h1:Lcz8mBdAVJIBVzewtcLocK12l3Y+JytZYpaMropDUws=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
@@ -386,7 +388,6 @@ github.com/snowflakedb/gosnowflake v1.7.2/go.mod h1:03tW856vc3ceM4rJuj7KO4dzqN7q
 github.com/sourcegraph/conc v0.3.0/go.mod h1:Sdozi7LEKbFPqYX2/J+iBAM6HpqSLTASQIKqDmF7Mt0=
 github.com/spaolacci/murmur3 v1.1.0/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/spf13/afero v1.12.0/go.mod h1:ZTlWwG4/ahT8W7T0WQ5uYmjI9duaLQGy3Q2OAl4sk/4=
-github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
 github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
@@ -401,7 +402,6 @@ github.com/tchap/go-patricia/v2 v2.3.1/go.mod h1:VZRHKAb53DLaG+nA9EaYYiaEx6YztwD
 github.com/tetratelabs/wazero v1.6.0/go.mod h1:0U0G41+ochRKoPKCJlh0jMg1CHkyfK8kDqiirMmKY8A=
 github.com/tidwall/btree v1.7.0/go.mod h1:twD9XRA5jj9VUQGELzDO4HPQTNJsoWWfYEL+EUQ2cKY=
 github.com/tidwall/gjson v1.14.2/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
-github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
 github.com/tidwall/pretty v1.2.1/go.mod h1:ITEVvHYasfjBbM0u2Pg8T2nJnzm8xPwvNhhsoaGGjNU=
 github.com/tidwall/sjson v1.2.5/go.mod h1:Fvgq9kS/6ociJEDnK0Fk1cpYF4FIW6ZF7LAe+6jwd28=
 github.com/trinodb/trino-go-client v0.313.0/go.mod h1:YpZf2WAClFhU+n0ZhdkmMbugYaMRM/mjywiQru0wpeQ=
@@ -475,6 +475,7 @@ golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.2.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sync v0.9.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.10.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sync v0.11.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20200106162015-b016eb3dc98e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200615200032-f1bc736245b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -490,6 +491,7 @@ golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.26.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.27.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/telemetry v0.0.0-20240521205824-bda55230c457/go.mod h1:pRgIJT+bRLFKnoM1ldnzKoxTIn14Yxz928LQRYYgIN0=
 golang.org/x/term v0.1.0/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=

plugins/agent_bridge_acp.go

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright (c) 2025 Cisco and/or its affiliates.
+// Copyright AGNTCY Contributors (https://github.com/agntcy)
 // SPDX-License-Identifier: Apache-2.0
 
 package main

plugins/agent_bridge_config.go

@@ -92,6 +92,16 @@ func getConfigValue(defaultValue string, configData map[string]any, configMapKey
 	return ret
 }
 
+func getEnvOrDefault(value string, envKey string, defaultValue string) string {
+	if value == "" {
+		value = os.Getenv(envKey)
+		if value == "" {
+			value = defaultValue
+		}
+	}
+	return value
+}
+
 func parseConfigData(apiId string, configData map[string]any) (*PluginDataConfig, error) {
 	logger.Debugf("[+] Parsing config for api id: %s", apiId)