added: go_template input for get resource tool

strowk · Jan 19, 2025 · 1670381 · 1670381
1 parent c0652ea
commit 1670381
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Showing 5 changed files with 136 additions and 12 deletions.
diff --git a/internal/content/json.go b/internal/content/json.go
@@ -6,7 +6,7 @@ import (
 	"github.com/strowk/foxy-contexts/pkg/mcp"
 )
 
-func NewJsonContent(v interface{}) (mcp.TextContent, error) {
+func NewJsonContent(v any) (mcp.TextContent, error) {
 	contents, err := json.Marshal(v)
 	if err != nil {
 		return mcp.TextContent{}, err

diff --git a/internal/k8s/apps/v1/deployment/get_deployment.go b/internal/k8s/apps/v1/deployment/get_deployment.go
@@ -2,6 +2,9 @@ package deployment
 
 import (
 	"context"
+	"encoding/json"
+	"html/template"
+	"strings"
 
 	"github.com/strowk/foxy-contexts/pkg/mcp"
 	"github.com/strowk/mcp-k8s-go/internal/content"
@@ -11,20 +14,59 @@ import (
 	"k8s.io/client-go/kubernetes"
 )
 
-func GetDeployment(clientset kubernetes.Interface, namespace string, name string) *mcp.CallToolResult {
+func GetDeployment(
+	clientset kubernetes.Interface,
+	namespace string,
+	name string,
+	templateStr string,
+) *mcp.CallToolResult {
 	deployment, err := clientset.AppsV1().Deployments(namespace).Get(context.Background(), name, metav1.GetOptions{})
 	if err != nil {
 		return utils.ErrResponse(err)
 	}
-	utils.SanitizeObjectMeta(&deployment.ObjectMeta)
 
-	c, err := content.NewJsonContent(deployment)
-	if err != nil {
-		return utils.ErrResponse(err)
+	var cnt interface{}
+	if templateStr != "" {
+		tmpl, err := template.New("template").Parse(templateStr)
+		if err != nil {
+			return utils.ErrResponse(err)
+		}
+
+		// transforming deployment to JSON and back so that it has clear structure
+		parsedDeployment, err := json.Marshal(deployment)
+		if err != nil {
+			return utils.ErrResponse(err)
+		}
+
+		var parsedDeploymentMap map[string]interface{}
+		err = json.Unmarshal(parsedDeployment, &parsedDeploymentMap)
+		if err != nil {
+			return utils.ErrResponse(err)
+		}
+
+		buf := new(strings.Builder)
+
+		err = tmpl.Execute(buf, parsedDeploymentMap)
+		if err != nil {
+			return utils.ErrResponse(err)
+		}
+
+		cnt = mcp.TextContent{
+			Type: "text",
+			Text: buf.String(),
+		}
+	} else {
+		utils.SanitizeObjectMeta(&deployment.ObjectMeta)
+		c, err := content.NewJsonContent(deployment)
+		if err != nil {
+			return utils.ErrResponse(err)
+		}
+		cnt = c
 	}
+
 	return &mcp.CallToolResult{
 		Meta:    map[string]interface{}{},
-		Content: []interface{}{c},
+		Content: []interface{}{cnt},
 		IsError: utils.Ptr(false),
 	}
 }
diff --git a/internal/k8s/apps/v1/deployment/get_deployment_test.yaml b/internal/k8s/apps/v1/deployment/get_deployment_test.yaml
@@ -38,3 +38,34 @@ out:
         "isError": false,
       },
   }
+
+---
+case: Get k8s deployment name
+in:
+  {
+    "jsonrpc": "2.0",
+    "method": "tools/call",
+    "id": 2,
+    "params":
+      {
+        "name": "get-k8s-resource",
+        "arguments":
+          {
+            "context": "k3d-mcp-k8s-integration-test",
+            "namespace": "test-deployment",
+            "kind": "deployment",
+            "name": "nginx-deployment",
+            "go_template": "{{ .metadata.name }}",
+          },
+      },
+  }
+out:
+  {
+    "jsonrpc": "2.0",
+    "id": 2,
+    "result":
+      {
+        "content": [{ "type": "text", "text": "nginx-deployment" }],
+        "isError": false,
+      },
+  }
diff --git a/internal/k8s/core/v1/pod/get_pod_test.yaml b/internal/k8s/core/v1/pod/get_pod_test.yaml
@@ -32,3 +32,31 @@ out:
         "isError": false,
       },
   }
+
+---
+case: Get k8s pod dnsPolicy
+in:
+  {
+    "jsonrpc": "2.0",
+    "method": "tools/call",
+    "id": 2,
+    "params":
+      {
+        "name": "get-k8s-resource",
+        "arguments":
+          {
+            "context": "k3d-mcp-k8s-integration-test",
+            "namespace": "test",
+            "kind": "pod",
+            "name": "nginx",
+            "go_template": "{{ .spec.dnsPolicy }}",
+          },
+      },
+  }
+out:
+  {
+    "jsonrpc": "2.0",
+    "id": 2,
+    "result":
+      { "content": [{ "type": "text", "text": "ClusterFirst" }], "isError": false },
+  }
diff --git a/internal/tools/get_resource_tool.go b/internal/tools/get_resource_tool.go
@@ -3,6 +3,7 @@ package tools
 import (
 	"context"
 	"fmt"
+	"html/template"
 	"strings"
 
 	"github.com/strowk/foxy-contexts/pkg/fxctx"
@@ -26,6 +27,7 @@ func NewGetResourceTool(pool k8s.ClientPool) fxctx.Tool {
 	groupProperty := "group"
 	versionProperty := "version"
 	nameProperty := "name"
+	templateProperty := "go_template"
 
 	inputSchema := toolinput.NewToolInputSchema(
 		toolinput.WithString(contextProperty, "Name of the Kubernetes context to use, defaults to current context"),
@@ -34,6 +36,7 @@ func NewGetResourceTool(pool k8s.ClientPool) fxctx.Tool {
 		toolinput.WithString(versionProperty, "API Version of the resource to get"),
 		toolinput.WithRequiredString(kindProperty, "Kind of resource to get"),
 		toolinput.WithRequiredString(nameProperty, "Name of the resource to get"),
+		toolinput.WithString(templateProperty, "Go template to render the output, if not specified, the complete JSON object will be returned"),
 	)
 
 	return fxctx.NewTool(
@@ -72,8 +75,10 @@ func NewGetResourceTool(pool k8s.ClientPool) fxctx.Tool {
 				return utils.ErrResponse(err)
 			}
 
+			templateStr := input.StringOr(templateProperty, "")
+
 			if strings.ToLower(kind) == "deployment" && (group == "apps" || group == "") && (version == "v1" || version == "") {
-				return deployment.GetDeployment(clientset, namespace, name)
+				return deployment.GetDeployment(clientset, namespace, name, templateStr)
 			}
 
 			res, err := clientset.Discovery().ServerPreferredResources()
@@ -120,11 +125,29 @@ func NewGetResourceTool(pool k8s.ClientPool) fxctx.Tool {
 							}
 						}
 
-						cnt, err := content.NewJsonContent(unstructured.Object)
-						if err != nil {
-							return utils.ErrResponse(err)
+						var cnt any
+						if templateStr != "" {
+							tmpl, err := template.New("template").Parse(templateStr)
+							if err != nil {
+								return utils.ErrResponse(err)
+							}
+							buf := new(strings.Builder)
+							err = tmpl.Execute(buf, object)
+							if err != nil {
+								return utils.ErrResponse(err)
+							}
+							cnt = mcp.TextContent{
+								Type: "text",
+								Text: buf.String(),
+							}
+						} else {
+							c, err := content.NewJsonContent(object)
+							if err != nil {
+								return utils.ErrResponse(err)
+							}
+							cnt = c
 						}
-						var contents = []interface{}{cnt}
+						var contents = []any{cnt}
 
 						return &mcp.CallToolResult{
 							Meta:    map[string]interface{}{},