[cmd/opampsupervisor] Validate that the HUP config reload cannot be used on Windows

.chloggen/supervisor-hup-test-windows.yaml

@@ -0,0 +1,30 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: cmd/opampsupervisor
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add a config validation to prevent usage of HUP config reload on Windows.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [41077]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: |
+  As SIGHUP is not supported on Windows, a new validation was added to ensure
+  that the Supervisor's cannot be configured to reload agent configuration using
+  it.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

cmd/opampsupervisor/supervisor/config/config.go

@@ -219,6 +219,10 @@ func (a Agent) Validate() error {
 		return errors.New("agent::config_apply_timeout must be valid duration")
 	}
 
+	if runtime.GOOS == "windows" && a.UseHUPConfigReload {
+		return errors.New("agent::use_hup_config_reload is not supported on Windows")
+	}
+
 	return nil
 }
 

cmd/opampsupervisor/supervisor/config/config_test.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 	"time"
 
@@ -26,6 +27,7 @@ func TestValidate(t *testing.T) {
 		name          string
 		config        Supervisor
 		expectedError string
+		skipFunc      func() (bool, string)
 	}{
 		{
 			name: "Valid filled out config",
@@ -373,6 +375,33 @@ func TestValidate(t *testing.T) {
 			},
 			expectedError: "agent::config_apply_timeout must be valid duration",
 		},
+		{
+			name: "HUP config reload not supported on Windows",
+			config: Supervisor{
+				Server: OpAMPServer{
+					Endpoint: "wss://localhost:9090/opamp",
+					Headers: http.Header{
+						"Header1": []string{"HeaderValue"},
+					},
+					TLS: tlsConfig,
+				},
+				Agent: Agent{
+					Executable:              "${file_path}",
+					OrphanDetectionInterval: 5 * time.Second,
+					ConfigApplyTimeout:      2 * time.Second,
+					BootstrapTimeout:        5 * time.Second,
+					UseHUPConfigReload:      true,
+				},
+				Capabilities: Capabilities{
+					AcceptsRemoteConfig: true,
+				},
+				Storage: Storage{
+					Directory: "/etc/opamp-supervisor/storage",
+				},
+			},
+			expectedError: "agent::use_hup_config_reload is not supported on Windows",
+			skipFunc:      func() (bool, string) { return runtime.GOOS != "windows", "HUP reload not supported on Windows" },
+		},
 	}
 
 	// create some fake files for validating agent config
@@ -383,6 +412,12 @@ func TestValidate(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
+			if tc.skipFunc != nil {
+				if skip, reason := tc.skipFunc(); skip {
+					t.Skip(reason)
+				}
+			}
+
 			// Fill in path to agent executable
 			tc.config.Agent.Executable = os.Expand(tc.config.Agent.Executable,
 				func(s string) string {