api/v2: add read-only tailnet settings endpoint

Report the settings the k8s operator reads, computed from config; writes return 501.
2026-07-08 00:50:20 +09:00 · 2026-06-20 20:16:51 +00:00
parent 3cddc07026
commit e2e9fe3081
1 changed files with 99 additions and 0 deletions
@@ -0,0 +1,99 @@
+package apiv2
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"github.com/danielgtaylor/huma/v2"
+	"github.com/juanfont/headscale/hscontrol/types"
+)
+
+func init() {
+	registrations = append(registrations, registerSettings)
+}
+
+// TailnetSettings is the Tailscale tailnet-settings response. Headscale's config
+// is file-based and mostly not runtime-mutable, so only a few fields carry a
+// real value; the rest report the honest "off"/default.
+type TailnetSettings struct {
+	ACLsExternallyManagedOn bool   `json:"aclsExternallyManagedOn"`
+	ACLsExternalLink        string `json:"aclsExternalLink"`
+
+	DevicesApprovalOn      bool `json:"devicesApprovalOn"`
+	DevicesAutoUpdatesOn   bool `json:"devicesAutoUpdatesOn"`
+	DevicesKeyDurationDays int  `json:"devicesKeyDurationDays"`
+
+	UsersApprovalOn                        bool   `json:"usersApprovalOn"`
+	UsersRoleAllowedToJoinExternalTailnets string `json:"usersRoleAllowedToJoinExternalTailnets"`
+
+	NetworkFlowLoggingOn        bool `json:"networkFlowLoggingOn"`
+	RegionalRoutingOn           bool `json:"regionalRoutingOn"`
+	PostureIdentityCollectionOn bool `json:"postureIdentityCollectionOn"`
+	HTTPSEnabled                bool `json:"httpsEnabled"`
+}
+
+type (
+	getSettingsInput struct {
+		Tailnet string `path:"tailnet"`
+	}
+	settingsOutput struct {
+		Body TailnetSettings
+	}
+	patchSettingsInput struct {
+		Tailnet string `path:"tailnet"`
+		// Accepted and ignored; updating settings is not supported.
+		Body json.RawMessage
+	}
+)
+
+func registerSettings(api huma.API, b Backend) {
+	settingsTags := []string{"TailnetSettings", "Tailscale compat"}
+
+	huma.Register(api, requireScope(huma.Operation{
+		OperationID: "getTailnetSettings",
+		Method:      http.MethodGet,
+		Path:        "/api/v2/tailnet/{tailnet}/settings",
+		Summary:     "Get tailnet settings",
+		Tags:        settingsTags,
+		Security:    security,
+		Errors:      []int{http.StatusUnauthorized, http.StatusForbidden, http.StatusNotFound},
+	}, ScopeFeatureSettingsRead), func(ctx context.Context, in *getSettingsInput) (*settingsOutput, error) {
+		err := requireDefaultTailnet(in.Tailnet)
+		if err != nil {
+			return nil, err
+		}
+
+		cfg := b.Cfg
+
+		return &settingsOutput{Body: TailnetSettings{
+			// File-mode policy is genuinely externally managed (read-only via API).
+			ACLsExternallyManagedOn:                cfg.Policy.Mode == types.PolicyModeFile,
+			DevicesKeyDurationDays:                 int(cfg.Node.Expiry / (24 * time.Hour)),
+			HTTPSEnabled:                           cfg.TLS.CertPath != "" || cfg.TLS.LetsEncrypt.Hostname != "",
+			UsersRoleAllowedToJoinExternalTailnets: "none",
+		}}, nil
+	})
+
+	huma.Register(api, requireScope(huma.Operation{
+		OperationID: "updateTailnetSettings",
+		Method:      http.MethodPatch,
+		Path:        "/api/v2/tailnet/{tailnet}/settings",
+		Summary:     "Update tailnet settings",
+		Tags:        settingsTags,
+		Security:    security,
+		// The body is accepted but ignored; skip validation.
+		SkipValidateBody: true,
+		Errors:           []int{http.StatusUnauthorized, http.StatusForbidden, http.StatusNotFound, http.StatusNotImplemented},
+	}, ScopeFeatureSettings), func(ctx context.Context, in *patchSettingsInput) (*settingsOutput, error) {
+		err := requireDefaultTailnet(in.Tailnet)
+		if err != nil {
+			return nil, err
+		}
+
+		return nil, huma.Error501NotImplemented(
+			"updating tailnet settings is not supported by Headscale",
+		)
+	})
+}