feat: switch currently viewed cluster

src/pkg/api/docs/docs.go

@@ -28,6 +28,52 @@ const docTemplate = `{
                 }
             }
         },
+        "/api/v1/cluster": {
+            "post": {
+                "description": "Swith the currently viewed cluster",
+                "consumes": [
+                    "application/json"
+                ],
+                "tags": [
+                    "cluster"
+                ],
+                "parameters": [
+                    {
+                        "description": "example body: {",
+                        "name": "request",
+                        "in": "body",
+                        "required": true,
+                        "schema": {
+                            "type": "object",
+                            "additionalProperties": {
+                                "$ref": "#/definitions/client.ClusterInfo"
+                            }
+                        }
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK"
+                    }
+                }
+            }
+        },
+        "/api/v1/clusters": {
+            "get": {
+                "description": "get list of clusters with context names from local kubeconfig",
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "clusters"
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK"
+                    }
+                }
+            }
+        },
         "/api/v1/resources/cluster-ops/hpas": {
             "get": {
                 "description": "Get HPAs",
@@ -3109,6 +3155,22 @@ const docTemplate = `{
                 }
             }
         }
+    },
+    "definitions": {
+        "client.ClusterInfo": {
+            "type": "object",
+            "properties": {
+                "context": {
+                    "type": "string"
+                },
+                "name": {
+                    "type": "string"
+                },
+                "selected": {
+                    "type": "boolean"
+                }
+            }
+        }
     }
 }`
 

src/pkg/api/docs/swagger.json

@@ -17,6 +17,52 @@
                 }
             }
         },
+        "/api/v1/cluster": {
+            "post": {
+                "description": "Swith the currently viewed cluster",
+                "consumes": [
+                    "application/json"
+                ],
+                "tags": [
+                    "cluster"
+                ],
+                "parameters": [
+                    {
+                        "description": "example body: {",
+                        "name": "request",
+                        "in": "body",
+                        "required": true,
+                        "schema": {
+                            "type": "object",
+                            "additionalProperties": {
+                                "$ref": "#/definitions/client.ClusterInfo"
+                            }
+                        }
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK"
+                    }
+                }
+            }
+        },
+        "/api/v1/clusters": {
+            "get": {
+                "description": "get list of clusters with context names from local kubeconfig",
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "clusters"
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK"
+                    }
+                }
+            }
+        },
         "/api/v1/resources/cluster-ops/hpas": {
             "get": {
                 "description": "Get HPAs",
@@ -3098,5 +3144,21 @@
                 }
             }
         }
+    },
+    "definitions": {
+        "client.ClusterInfo": {
+            "type": "object",
+            "properties": {
+                "context": {
+                    "type": "string"
+                },
+                "name": {
+                    "type": "string"
+                },
+                "selected": {
+                    "type": "boolean"
+                }
+            }
+        }
     }
 }

src/pkg/api/docs/swagger.yaml

@@ -1,3 +1,13 @@
+definitions:
+  client.ClusterInfo:
+    properties:
+      context:
+        type: string
+      name:
+        type: string
+      selected:
+        type: boolean
+    type: object
 info:
   contact: {}
 paths:
@@ -10,6 +20,35 @@ paths:
           description: OK
       tags:
       - auth
+  /api/v1/cluster:
+    post:
+      consumes:
+      - application/json
+      description: Swith the currently viewed cluster
+      parameters:
+      - description: 'example body: {'
+        in: body
+        name: request
+        required: true
+        schema:
+          additionalProperties:
+            $ref: '#/definitions/client.ClusterInfo'
+          type: object
+      responses:
+        "200":
+          description: OK
+      tags:
+      - cluster
+  /api/v1/clusters:
+    get:
+      description: get list of clusters with context names from local kubeconfig
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: OK
+      tags:
+      - clusters
   /api/v1/resources/cluster-ops/hpas:
     get:
       consumes:

src/pkg/api/handlers.go

@@ -13,6 +13,7 @@ import (
 	_ "github.com/defenseunicorns/uds-runtime/src/pkg/api/docs" //nolint:staticcheck
 	"github.com/defenseunicorns/uds-runtime/src/pkg/api/resources"
 	"github.com/defenseunicorns/uds-runtime/src/pkg/api/rest"
+	"github.com/defenseunicorns/uds-runtime/src/pkg/k8s/client"
 	"github.com/defenseunicorns/uds-runtime/src/pkg/k8s/session"
 )
 
@@ -935,3 +936,22 @@ func healthz(w http.ResponseWriter, _ *http.Request) {
 		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
 	}
 }
+
+// @Description get list of clusters with context names from local kubeconfig
+// @Tags clusters
+// @Produce json
+// @Success 200
+// @Router /api/v1/clusters [get]
+func getClusters(ks *session.K8sSession) func(w http.ResponseWriter, r *http.Request) {
+	return client.ServeClusters(ks.InCluster, ks.CurrentCtx)
+}
+
+// @Description Switch the currently viewed cluster
+// @Tags cluster
+// @Param request body map[string]client.ClusterInfo true "example body: {"cluster": {"name": string, "context": string, "selected": bool}}"
+// @Accept json
+// @Success 200
+// @Router /api/v1/cluster [post]
+func switchCluster(ks *session.K8sSession) func(w http.ResponseWriter, r *http.Request) {
+	return ks.Switch()
+}

src/pkg/api/start.go

@@ -66,6 +66,8 @@ func Setup(assets *embed.FS) (*chi.Mux, bool, error) {
 	r.Get("/cluster-check", checkClusterConnection(k8sSession))
 	r.Route("/api/v1", func(r chi.Router) {
 		r.Get("/auth", authHandler)
+		r.Get("/clusters", withLatestSession(k8sSession, getClusters))
+		r.Post("/cluster", switchCluster(k8sSession))
 		r.Route("/monitor", func(r chi.Router) {
 			r.Get("/pepr/", monitor.Pepr)
 			r.Get("/pepr/{stream}", monitor.Pepr)
@@ -304,3 +306,9 @@ func withLatestCache(k8sSession *session.K8sSession, handler func(cache *resourc
 		handler(k8sSession.Cache)(w, r)
 	}
 }
+
+func withLatestSession(k8sSession *session.K8sSession, handler func(k8sSession *session.K8sSession) func(w http.ResponseWriter, r *http.Request)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		handler(k8sSession)(w, r)
+	}
+}

src/pkg/k8s/client/client.go

@@ -4,11 +4,15 @@
 package client
 
 import (
+	"encoding/json"
 	"fmt"
+	"log/slog"
+	"net/http"
 
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
+	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 	metricsv "k8s.io/metrics/pkg/client/clientset/versioned"
 )
 
@@ -19,11 +23,17 @@ type Clients struct {
 	Config        *rest.Config
 }
 
-// NewClient creates new Kubernetes cluster clients
-func NewClient() (*Clients, error) {
+type ClusterInfo struct {
+	Name     string `json:"name"`
+	Context  string `json:"context"`
+	Selected bool   `json:"selected"`
+}
+
+// New creates new Kubernetes cluster clients with the option of overriding the default config
+func New(overrides *clientcmd.ConfigOverrides) (*Clients, error) {
 	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
 		clientcmd.NewDefaultClientConfigLoadingRules(),
-		&clientcmd.ConfigOverrides{}).ClientConfig()
+		overrides).ClientConfig()
 
 	if err != nil {
 		return nil, err
@@ -46,24 +56,22 @@ func NewClient() (*Clients, error) {
 	}, nil
 }
 
-// IsRunningInCluster checks if the application is running in cluster
-func IsRunningInCluster() (bool, error) {
-	_, err := rest.InClusterConfig()
+func rawConfig() (clientcmdapi.Config, error) {
+	rules := clientcmd.NewDefaultClientConfigLoadingRules()
+	return clientcmd.NewNonInteractiveDeferredLoadingClientConfig(rules, &clientcmd.ConfigOverrides{}).RawConfig()
+}
 
-	if err == rest.ErrNotInCluster {
-		return false, nil
-	} else if err != nil {
-		return true, err
+func Contexts() (map[string]*clientcmdapi.Context, error) {
+	config, err := rawConfig()
+	if err != nil {
+		return nil, err
 	}
-
-	return true, nil
+	return config.Contexts, nil
 }
 
-// Declare GetCurrentContext as a variable so it can be mocked
-var GetCurrentContext = func() (string, string, error) {
-	// Actual implementation of GetCurrentContext
-	rules := clientcmd.NewDefaultClientConfigLoadingRules()
-	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(rules, &clientcmd.ConfigOverrides{}).RawConfig()
+// Declare CurrentContext as a variable so it can be mocked
+var CurrentContext = func() (string, string, error) {
+	config, err := rawConfig()
 	if err != nil {
 		return "", "", err
 	}
@@ -74,3 +82,65 @@ var GetCurrentContext = func() (string, string, error) {
 	}
 	return contextName, context.Cluster, nil
 }
+
+func ServeClusters(inCluster bool, currentContext string) http.HandlerFunc {
+	return func(w http.ResponseWriter, _ *http.Request) {
+		w.Header().Set("Content-Type", "text/json; charset=utf-8")
+		w.Header().Set("Cache-Control", "no-cache")
+
+		// running in cluster return []
+		if inCluster {
+			data, err := json.Marshal([]interface{}{})
+			if err != nil {
+				slog.Error("Failed to marshal empty data", "error", err)
+				http.Error(w, "JSON marshalling error", http.StatusInternalServerError)
+			}
+
+			// Write the data to the response
+			if _, err := w.Write(data); err != nil {
+				http.Error(w, "Failed to write data", http.StatusInternalServerError)
+				return
+			}
+		}
+
+		contexts, err := Contexts()
+		if err != nil {
+			slog.Error("Failed to get contexts", "error", err)
+			http.Error(w, "Failed to get contexts", http.StatusInternalServerError)
+			return
+		}
+
+		slog.Debug("ServeClusters called", "inCluster", inCluster, "currentContext", currentContext)
+
+		var clusters []ClusterInfo
+		for ctxName, context := range contexts {
+			clusters = append(clusters, ClusterInfo{Name: context.Cluster, Context: ctxName, Selected: currentContext == ctxName})
+		}
+
+		data, err := json.Marshal(clusters)
+		if err != nil {
+			slog.Error("Failed to marshal contexts", "error", err)
+			http.Error(w, "JSON marshalling error", http.StatusInternalServerError)
+			return
+		}
+
+		// Write the data to the response
+		if _, err := w.Write(data); err != nil {
+			http.Error(w, "Failed to write data", http.StatusInternalServerError)
+			return
+		}
+	}
+}
+
+// IsRunningInCluster checks if the application is running in cluster
+func IsRunningInCluster() (bool, error) {
+	_, err := rest.InClusterConfig()
+
+	if err == rest.ErrNotInCluster {
+		return false, nil
+	} else if err != nil {
+		return true, err
+	}
+
+	return true, nil
+}