fix: isolate tests from developer-local configuration files

agent/lifecycle/keymanagementagent/launcher/launcher_test.go

@@ -20,6 +20,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/eclipse-cfm/cfm/common/fixtures"
 	"github.com/eclipse-cfm/cfm/common/natsclient"
 	"github.com/eclipse-cfm/cfm/common/natsfixtures"
 	"github.com/nats-io/nats.go/jetstream"
@@ -43,6 +44,8 @@ func TestKeyManagementAgent_Integration(t *testing.T) {
 	require.NoError(t, err)
 	defer natsfixtures.TeardownNatsContainer(ctx, nt)
 
+	fixtures.IsolateConfig(t)
+
 	t.Setenv("KMAGENT_URI", nt.URI)
 	t.Setenv("KMAGENT_BUCKET", bucket)
 	t.Setenv("KMAGENT_STREAM", streamName)

common/fixtures/fixtures.go

@@ -15,8 +15,16 @@ package fixtures
 import (
 	"net"
 	"testing"
+
+	"github.com/eclipse-cfm/cfm/common/system"
 )
 
+// IsolateConfig points the configuration file search path at an empty temp directory so that configuration files on
+// the developer's machine (e.g. $HOME/.appname) cannot leak into the test. The override is undone when the test ends.
+func IsolateConfig(t *testing.T) {
+	t.Setenv(system.ConfigDirEnvVar, t.TempDir())
+}
+
 // GetRandomPort returns a random available port or fails the test
 func GetRandomPort(t *testing.T) int {
 	listener, err := net.Listen("tcp", ":0")

common/lifecycleagent/agent_test.go

@@ -20,6 +20,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/eclipse-cfm/cfm/common/fixtures"
 	"github.com/eclipse-cfm/cfm/common/lifecycleagent"
 	"github.com/eclipse-cfm/cfm/common/natsclient"
 	"github.com/eclipse-cfm/cfm/common/natsfixtures"
@@ -73,6 +74,8 @@ func provisionStream(t *testing.T, ctx context.Context, nt *natsfixtures.NatsTes
 }
 
 func setupAgentEnv(t *testing.T, prefix, uri string) {
+	fixtures.IsolateConfig(t)
+
 	// viper uppercases the env prefix and key, so the environment variables must be uppercase.
 	p := strings.ToUpper(prefix)
 	t.Setenv(p+"_URI", uri)

common/system/config.go

@@ -14,19 +14,29 @@ package system
 
 import (
 	"fmt"
+	"os"
 	"strings"
 
 	"github.com/spf13/viper"
 )
 
+// ConfigDirEnvVar overrides the configuration file search path. When set, only the given directory is searched for
+// configuration files, replacing the default locations entirely. This pins the config location in deployments and
+// isolates tests from configuration files on the developer's machine.
+const ConfigDirEnvVar = "CFM_CONFIG_DIR"
+
 // LoadConfigOrPanic initializes a Config instance with the specified configuration name.
 // Configuration will be read from a file (if it exists) and can be overridden using environment variables.
 func LoadConfigOrPanic(name string) *viper.Viper {
 	v := viper.New()
 	v.SetConfigName(name)
-	v.AddConfigPath("/etc/appname/")
-	v.AddConfigPath("$HOME/.appname")
-	v.AddConfigPath(".")
+	if dir := os.Getenv(ConfigDirEnvVar); dir != "" {
+		v.AddConfigPath(dir)
+	} else {
+		v.AddConfigPath("/etc/appname/")
+		v.AddConfigPath("$HOME/.appname")
+		v.AddConfigPath(".")
+	}
 	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 	v.AutomaticEnv()
 	v.SetEnvPrefix(name)

common/system/config_test.go

@@ -11,15 +11,10 @@ import (
 
 const appName = "testapp"
 
-//nolint:errcheck
 func TestLoadConfigFromEnvironment(t *testing.T) {
 	// setup
-	os.Setenv("TESTAPP_FOO", "foo_value")
-	os.Setenv("TESTAPP_BAR", "bar_value")
-	defer func() {
-		os.Unsetenv("FOO")
-		os.Unsetenv("BAR")
-	}()
+	t.Setenv("TESTAPP_FOO", "foo_value")
+	t.Setenv("TESTAPP_BAR", "bar_value")
 
 	v := LoadConfigOrPanic(appName)
 
@@ -50,6 +45,27 @@ bar: "bar_value"
 	assert.Equal(t, "bar_value", v.GetString("bar"))
 }
 
+func TestLoadConfigDirOverride(t *testing.T) {
+	// a config file in the current directory, which must be ignored when the override is set
+	cwdContent := []byte(`foo: "cwd_value"`)
+	require.NoError(t, os.WriteFile("./testapp.yaml", cwdContent, 0644))
+	defer func() { _ = os.Remove("./testapp.yaml") }()
+
+	// a config file in the override directory
+	overrideDir := t.TempDir()
+	overrideContent := []byte(`foo: "override_value"`)
+	require.NoError(t, os.WriteFile(filepath.Join(overrideDir, "testapp.yaml"), overrideContent, 0644))
+
+	t.Setenv(ConfigDirEnvVar, overrideDir)
+	v := LoadConfigOrPanic(appName)
+	assert.Equal(t, "override_value", v.GetString("foo"), "only the override directory must be searched")
+
+	// pointing the override at an empty directory must yield no file-based configuration at all
+	t.Setenv(ConfigDirEnvVar, t.TempDir())
+	v = LoadConfigOrPanic(appName)
+	assert.Empty(t, v.GetString("foo"), "config files outside the override directory must be ignored")
+}
+
 //nolint:errcheck
 func TestLoadConfigEnvPriorityOverFile(t *testing.T) {
 	// create the config file
@@ -68,12 +84,8 @@ bar: "bar_value_file"
 	defer os.Remove("./testapp.yaml")
 
 	// Set environment variables
-	os.Setenv("TESTAPP_FOO", "foo_value_file")
-	os.Setenv("TESTAPP_BAR", "bar_value_env")
-	defer func() {
-		os.Unsetenv("TESTAPP_FOO")
-		os.Unsetenv("TESTAPP_BAR")
-	}()
+	t.Setenv("TESTAPP_FOO", "foo_value_file")
+	t.Setenv("TESTAPP_BAR", "bar_value_env")
 
 	v := LoadConfigOrPanic(appName)
 

e2e/e2etests/fixtures.go

@@ -44,6 +44,8 @@ func launchPlatformWithAgent(t *testing.T, natsURI string, pgDsn string) *e2efix
 }
 
 func launchPlatform(t *testing.T, natsURI string, pgDsn string) (chan struct{}, *e2efixtures.ApiClient) {
+	fixtures.IsolateConfig(t)
+
 	_ = os.Setenv("TM_POSTGRES", "true")
 	_ = os.Setenv("TM_DSN", pgDsn)
 	_ = os.Setenv("TM_URI", natsURI)

e2e/e2etests/lifecycleagent_test.go

@@ -19,6 +19,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/eclipse-cfm/cfm/common/fixtures"
 	"github.com/eclipse-cfm/cfm/common/lifecycleagent"
 	"github.com/eclipse-cfm/cfm/common/natsclient"
 	"github.com/eclipse-cfm/cfm/common/natsfixtures"
@@ -74,6 +75,8 @@ func Test_VerifyLifecycleAgentDispatchesCloudEvent(t *testing.T) {
 	})
 	require.NoError(t, err)
 
+	fixtures.IsolateConfig(t)
+
 	// viper uppercases the env prefix and key, so the environment variables must be uppercase.
 	p := strings.ToUpper(agentName)
 	t.Setenv(p+"_URI", nt.URI)

e2e/testagent/launcher/launcher_test.go

@@ -14,10 +14,10 @@ package launcher
 
 import (
 	"context"
-	"os"
 	"testing"
 	"time"
 
+	"github.com/eclipse-cfm/cfm/common/fixtures"
 	"github.com/eclipse-cfm/cfm/common/natsclient"
 	"github.com/eclipse-cfm/cfm/common/natsfixtures"
 	"github.com/eclipse-cfm/cfm/common/runtime"
@@ -65,9 +65,10 @@ func TestTestAgent_Integration(t *testing.T) {
 	}
 
 	// Required agent config
-	_ = os.Setenv("TESTAGENT_URI", nt.URI)
-	_ = os.Setenv("TESTAGENT_BUCKET", "cfm-bucket")
-	_ = os.Setenv("TESTAGENT_STREAM", streamName)
+	fixtures.IsolateConfig(t)
+	t.Setenv("TESTAGENT_URI", nt.URI)
+	t.Setenv("TESTAGENT_BUCKET", "cfm-bucket")
+	t.Setenv("TESTAGENT_STREAM", streamName)
 
 	// Create and start the test agent
 	shutdownChannel := make(chan struct{})

pmanager/cmd/server/launcher/launcher_test.go

@@ -14,7 +14,6 @@ package launcher
 
 import (
 	"context"
-	"os"
 	"strconv"
 	"testing"
 	"time"
@@ -30,6 +29,8 @@ const (
 )
 
 func TestTestAgent_Integration(t *testing.T) {
+	fixtures.IsolateConfig(t)
+
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()
 
@@ -43,11 +44,11 @@ func TestTestAgent_Integration(t *testing.T) {
 	natsfixtures.SetupTestStream(t, ctx, nt.Client, streamName)
 
 	// Required agent config
-	_ = os.Setenv("PM_URI", nt.URI)
-	_ = os.Setenv("PM_BUCKET", "cfm-bucket")
-	_ = os.Setenv("PM_STREAM", streamName)
-	_ = os.Setenv("PM_HTTPPORT", strconv.Itoa(fixtures.GetRandomPort(t)))
-	_ = os.Setenv("PM_AUTH_ENABLED", "false")
+	t.Setenv("PM_URI", nt.URI)
+	t.Setenv("PM_BUCKET", "cfm-bucket")
+	t.Setenv("PM_STREAM", streamName)
+	t.Setenv("PM_HTTPPORT", strconv.Itoa(fixtures.GetRandomPort(t)))
+	t.Setenv("PM_AUTH_ENABLED", "false")
 
 	// Create and start the test agent
 	shutdownChannel := make(chan struct{})

pmanager/natsagent/launcher_test.go

@@ -13,25 +13,19 @@
 package natsagent
 
 import (
-	"os"
 	"testing"
 
+	"github.com/eclipse-cfm/cfm/common/fixtures"
 	"github.com/eclipse-cfm/cfm/common/system"
 	"github.com/eclipse-cfm/cfm/pmanager/api"
 	"github.com/stretchr/testify/require"
 )
 
 func Test_LaunchAgent_WithAssemblyProvider(t *testing.T) {
 	// Setup environment variables
-	_ = os.Setenv("TESTAGENT_URI", "nats://localhost:4222")
-	_ = os.Setenv("TESTAGENT_BUCKET", "test-bucket")
-	_ = os.Setenv("TESTAGENT_STREAM", "test-stream")
-
-	t.Cleanup(func() {
-		_ = os.Unsetenv("TESTAGENT_URI")
-		_ = os.Unsetenv("TESTAGENT_BUCKET")
-		_ = os.Unsetenv("TESTAGENT_STREAM")
-	})
+	t.Setenv("TESTAGENT_URI", "nats://localhost:4222")
+	t.Setenv("TESTAGENT_BUCKET", "test-bucket")
+	t.Setenv("TESTAGENT_STREAM", "test-stream")
 
 	// Create a flag to track if AssemblyProvider was called
 	var assemblyProviderCalled bool
@@ -90,16 +84,12 @@ func Test_LaunchAgent_WithAssemblyProvider(t *testing.T) {
 }
 
 func Test_LaunchAgent_WithoutAssemblyProvider(t *testing.T) {
-	// Setup environment variables
-	_ = os.Setenv("TESTAGENT_URI", "nats://localhost:4222")
-	_ = os.Setenv("TESTAGENT_BUCKET", "test-bucket")
-	_ = os.Setenv("TESTAGENT_STREAM", "test-stream")
+	fixtures.IsolateConfig(t)
 
-	t.Cleanup(func() {
-		_ = os.Unsetenv("TESTAGENT_URI")
-		_ = os.Unsetenv("TESTAGENT_BUCKET")
-		_ = os.Unsetenv("TESTAGENT_STREAM")
-	})
+	// Setup environment variables
+	t.Setenv("TESTAGENT_URI", "nats://localhost:4222")
+	t.Setenv("TESTAGENT_BUCKET", "test-bucket")
+	t.Setenv("TESTAGENT_STREAM", "test-stream")
 
 	// Create launcher config without AssemblyProvider
 	config := LauncherConfig{
@@ -125,15 +115,11 @@ func Test_LaunchAgent_WithoutAssemblyProvider(t *testing.T) {
 }
 
 func Test_loadAgentConfig_MissingRequiredParams(t *testing.T) {
+	fixtures.IsolateConfig(t)
+
 	// Test with missing URI
-	_ = os.Setenv("TESTAGENT_BUCKET", "test-bucket")
-	_ = os.Setenv("TESTAGENT_STREAM", "test-stream")
-
-	t.Cleanup(func() {
-		_ = os.Unsetenv("TESTAGENT_URI")
-		_ = os.Unsetenv("TESTAGENT_BUCKET")
-		_ = os.Unsetenv("TESTAGENT_STREAM")
-	})
+	t.Setenv("TESTAGENT_BUCKET", "test-bucket")
+	t.Setenv("TESTAGENT_STREAM", "test-stream")
 
 	// Verify that missing required params causes panic
 	require.Panics(t, func() {