Centralize effective config loading and path resolution

internal/cli/run.go

@@ -375,30 +375,28 @@ func runProcess(args []string, stdout, stderr io.Writer) int {
 		fmt.Fprintf(stderr, "audita process: invalid CLI configuration: %v\n", err)
 		return 2
 	}
-	configPath, configSource, err := resolveConfigPath(configPathOverride, configPathOverrideSet, os.LookupEnv)
+	effectiveConfig, err := config.LoadEffectiveConfig(configPathOverride, configPathOverrideSet)
 	if err != nil {
-		fmt.Fprintf(stderr, "audita process: %v\n", err)
+		var effectiveConfigErr *config.EffectiveConfigError
+		if errors.As(err, &effectiveConfigErr) {
+			switch effectiveConfigErr.Kind {
+			case config.EffectiveConfigErrorLoadFile, config.EffectiveConfigErrorApplyFile:
+				fmt.Fprintf(stderr, "audita process: invalid config file: %v\n", effectiveConfigErr)
+			case config.EffectiveConfigErrorApplyEnv:
+				fmt.Fprintf(stderr, "audita process: invalid environment configuration: %v\n", effectiveConfigErr)
+			default:
+				fmt.Fprintf(stderr, "audita process: %v\n", effectiveConfigErr)
+			}
+		} else {
+			fmt.Fprintf(stderr, "audita process: %v\n", err)
+		}
 		return 2
 	}
 
-	cfg := config.Default()
-	var configVersion *int
-	if configPath != "" {
-		fileCfg, fileErr := config.LoadFileConfig(configPath)
-		if fileErr != nil {
-			fmt.Fprintf(stderr, "audita process: invalid config file: %v\n", fileErr)
-			return 2
-		}
-		if applyErr := cfg.ApplyFileConfig(fileCfg); applyErr != nil {
-			fmt.Fprintf(stderr, "audita process: invalid config file: %v\n", applyErr)
-			return 2
-		}
-		configVersion = &fileCfg.Version
-	}
-	if err := cfg.ApplyEnvOverrides(); err != nil {
-		fmt.Fprintf(stderr, "audita process: invalid environment configuration: %v\n", err)
-		return 2
-	}
+	cfg := effectiveConfig.Config
+	configPath := effectiveConfig.ConfigPath
+	configSource := effectiveConfig.ConfigSource
+	configVersion := effectiveConfig.ConfigVersion
 
 	fs, pFlags := newProcessFlagSet(cfg, stderr)
 
@@ -679,28 +677,13 @@ func runConfigPrintEffective(args []string, stdout, stderr io.Writer) int {
 
 	configPathValue := strings.TrimSpace(*configPath)
 	configPathSet := configPathValue != ""
-	path, _, err := resolveConfigPath(configPathValue, configPathSet, os.LookupEnv)
+	effectiveConfig, err := config.LoadEffectiveConfig(configPathValue, configPathSet)
 	if err != nil {
 		fmt.Fprintf(stderr, "audita config print-effective: %v\n", err)
 		return 2
 	}
 
-	cfg := config.Default()
-	if path != "" {
-		fileCfg, fileErr := config.LoadFileConfig(path)
-		if fileErr != nil {
-			fmt.Fprintf(stderr, "audita config print-effective: %v\n", fileErr)
-			return 2
-		}
-		if applyErr := cfg.ApplyFileConfig(fileCfg); applyErr != nil {
-			fmt.Fprintf(stderr, "audita config print-effective: %v\n", applyErr)
-			return 2
-		}
-	}
-	if err := cfg.ApplyEnvOverrides(); err != nil {
-		fmt.Fprintf(stderr, "audita config print-effective: %v\n", err)
-		return 2
-	}
+	cfg := effectiveConfig.Config
 
 	redacted := cfg.Redacted()
 	out, err := json.MarshalIndent(redacted, "", "  ")
@@ -975,47 +958,6 @@ func findConfigPathOverride(args []string) (path string, set bool, err error) {
 	return "", false, nil
 }
 
-var statConfigPath = os.Stat
-
-func resolveConfigPath(cliConfigPath string, cliConfigPathSet bool, lookup func(string) (string, bool)) (path string, source string, err error) {
-	if cliConfigPathSet {
-		path = strings.TrimSpace(cliConfigPath)
-		if path == "" {
-			return "", "", fmt.Errorf("--config requires a non-empty path")
-		}
-		if _, statErr := statConfigPath(path); statErr != nil {
-			if os.IsNotExist(statErr) {
-				return "", "", fmt.Errorf("config file not found: %s", path)
-			}
-			return "", "", fmt.Errorf("cannot access config file %s: %w", path, statErr)
-		}
-		return path, "flag", nil
-	}
-
-	if raw, ok := lookup("AUDITA_CONFIG"); ok {
-		path = strings.TrimSpace(raw)
-		if path == "" {
-			return "", "", fmt.Errorf("AUDITA_CONFIG must not be empty")
-		}
-		if _, statErr := statConfigPath(path); statErr != nil {
-			if os.IsNotExist(statErr) {
-				return "", "", fmt.Errorf("config file not found: %s", path)
-			}
-			return "", "", fmt.Errorf("cannot access config file %s: %w", path, statErr)
-		}
-		return path, "env", nil
-	}
-
-	for _, defaultPath := range config.DefaultConfigSearchPaths {
-		if _, statErr := statConfigPath(defaultPath); statErr == nil {
-			return defaultPath, "default", nil
-		} else if !os.IsNotExist(statErr) {
-			return "", "", fmt.Errorf("cannot access config file %s: %w", defaultPath, statErr)
-		}
-	}
-	return "", "", nil
-}
-
 func isHelpCommand(args []string) bool {
 	if len(args) == 0 {
 		return false

internal/cli/run_test.go

@@ -98,66 +98,6 @@ func TestRunProcessHelpListsExpectedFlags(t *testing.T) {
 	}
 }
 
-func TestResolveConfigPathDefaultIgnoredWhenMissing(t *testing.T) {
-	lookup := func(string) (string, bool) { return "", false }
-	path, source, err := resolveConfigPath("", false, lookup)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if path != "" || source != "" {
-		t.Fatalf("expected no config path/source, got path=%q source=%q", path, source)
-	}
-}
-
-func TestResolveConfigPathDefaultPrefersUsrLocalOverEtc(t *testing.T) {
-	oldStat := statConfigPath
-	statConfigPath = func(path string) (os.FileInfo, error) {
-		if path == config.DefaultConfigPathUsrLocal || path == config.DefaultConfigPath {
-			return nil, nil
-		}
-		return nil, os.ErrNotExist
-	}
-	t.Cleanup(func() { statConfigPath = oldStat })
-
-	lookup := func(string) (string, bool) { return "", false }
-	path, source, err := resolveConfigPath("", false, lookup)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if source != "default" {
-		t.Fatalf("expected default source, got %q", source)
-	}
-	if path != config.DefaultConfigPathUsrLocal {
-		t.Fatalf("expected %q, got %q", config.DefaultConfigPathUsrLocal, path)
-	}
-}
-
-func TestResolveConfigPathDefaultFallsBackToEtc(t *testing.T) {
-	oldStat := statConfigPath
-	statConfigPath = func(path string) (os.FileInfo, error) {
-		if path == config.DefaultConfigPathUsrLocal {
-			return nil, os.ErrNotExist
-		}
-		if path == config.DefaultConfigPath {
-			return nil, nil
-		}
-		return nil, os.ErrNotExist
-	}
-	t.Cleanup(func() { statConfigPath = oldStat })
-
-	lookup := func(string) (string, bool) { return "", false }
-	path, source, err := resolveConfigPath("", false, lookup)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if source != "default" {
-		t.Fatalf("expected default source, got %q", source)
-	}
-	if path != config.DefaultConfigPath {
-		t.Fatalf("expected %q, got %q", config.DefaultConfigPath, path)
-	}
-}
-
 func TestRunConfigValidateSuccess(t *testing.T) {
 	var stdout bytes.Buffer
 	var stderr bytes.Buffer
@@ -258,6 +198,45 @@ func TestRunConfigPrintEffectiveOutputsRedactedJSON(t *testing.T) {
 	}
 }
 
+func TestRunConfigPrintEffectiveAppliesFileThenEnvironment(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	cfgPath := writeFile(t, "config.yml", "version: 1\nllm:\n  proposal:\n    model: file-model\n")
+	t.Setenv("AUDITA_MODEL", "env-model")
+
+	exitCode := Run([]string{"config", "print-effective", "--config", cfgPath}, &stdout, &stderr)
+	if exitCode != 0 {
+		t.Fatalf("expected success, got %d stderr=%q", exitCode, stderr.String())
+	}
+
+	var out struct {
+		PrimaryLLM struct {
+			Model string `json:"Model"`
+		} `json:"PrimaryLLM"`
+	}
+	if err := json.Unmarshal(stdout.Bytes(), &out); err != nil {
+		t.Fatalf("expected valid JSON output, got error: %v output=%q", err, stdout.String())
+	}
+	if out.PrimaryLLM.Model != "env-model" {
+		t.Fatalf("expected env model override in print-effective output, got %q", out.PrimaryLLM.Model)
+	}
+}
+
+func TestRunConfigValidateIgnoresEnvironmentOverrides(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	cfgPath := writeFile(t, "config.yml", "version: 1\n")
+	t.Setenv("AUDITA_MODULES", "made_up")
+
+	exitCode := Run([]string{"config", "validate", "--config", cfgPath}, &stdout, &stderr)
+	if exitCode != 0 {
+		t.Fatalf("expected success because config validate is file-only, got %d stderr=%q", exitCode, stderr.String())
+	}
+	if !strings.Contains(stdout.String(), "config is valid") {
+		t.Fatalf("expected success message, got %q", stdout.String())
+	}
+}
+
 func TestRunConfigCommandDoesNotRequireTranscriptOrGlossary(t *testing.T) {
 	var stdout bytes.Buffer
 	var stderr bytes.Buffer

internal/core/config/effective_config.go

@@ -0,0 +1,119 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+type EffectiveConfigErrorKind string
+
+const (
+	EffectiveConfigErrorResolvePath EffectiveConfigErrorKind = "resolve_path"
+	EffectiveConfigErrorLoadFile    EffectiveConfigErrorKind = "load_file"
+	EffectiveConfigErrorApplyFile   EffectiveConfigErrorKind = "apply_file"
+	EffectiveConfigErrorApplyEnv    EffectiveConfigErrorKind = "apply_env"
+)
+
+type EffectiveConfigError struct {
+	Kind EffectiveConfigErrorKind
+	Err  error
+}
+
+func (e *EffectiveConfigError) Error() string {
+	if e == nil || e.Err == nil {
+		return ""
+	}
+	return e.Err.Error()
+}
+
+func (e *EffectiveConfigError) Unwrap() error {
+	if e == nil {
+		return nil
+	}
+	return e.Err
+}
+
+type EffectiveConfig struct {
+	Config        Config
+	ConfigPath    string
+	ConfigSource  string
+	ConfigVersion *int
+}
+
+func ResolveConfigPath(cliConfigPath string, cliConfigPathSet bool) (path string, source string, err error) {
+	return resolveConfigPathWithLookup(cliConfigPath, cliConfigPathSet, os.LookupEnv, os.Stat, DefaultConfigSearchPaths)
+}
+
+func LoadEffectiveConfig(cliConfigPath string, cliConfigPathSet bool) (EffectiveConfig, error) {
+	return loadEffectiveConfigWithLookup(cliConfigPath, cliConfigPathSet, os.LookupEnv, os.Stat, DefaultConfigSearchPaths)
+}
+
+func loadEffectiveConfigWithLookup(cliConfigPath string, cliConfigPathSet bool, lookup func(string) (string, bool), statPath func(string) (os.FileInfo, error), defaultSearchPaths []string) (EffectiveConfig, error) {
+	configPath, configSource, err := resolveConfigPathWithLookup(cliConfigPath, cliConfigPathSet, lookup, statPath, defaultSearchPaths)
+	if err != nil {
+		return EffectiveConfig{}, &EffectiveConfigError{Kind: EffectiveConfigErrorResolvePath, Err: err}
+	}
+
+	cfg := Default()
+	var configVersion *int
+	if configPath != "" {
+		fileCfg, fileErr := LoadFileConfig(configPath)
+		if fileErr != nil {
+			return EffectiveConfig{}, &EffectiveConfigError{Kind: EffectiveConfigErrorLoadFile, Err: fileErr}
+		}
+		if applyErr := cfg.ApplyFileConfig(fileCfg); applyErr != nil {
+			return EffectiveConfig{}, &EffectiveConfigError{Kind: EffectiveConfigErrorApplyFile, Err: applyErr}
+		}
+		configVersion = &fileCfg.Version
+	}
+	if applyEnvErr := cfg.applyEnvOverrides(lookup); applyEnvErr != nil {
+		return EffectiveConfig{}, &EffectiveConfigError{Kind: EffectiveConfigErrorApplyEnv, Err: applyEnvErr}
+	}
+
+	return EffectiveConfig{
+		Config:        cfg,
+		ConfigPath:    configPath,
+		ConfigSource:  configSource,
+		ConfigVersion: configVersion,
+	}, nil
+}
+
+func resolveConfigPathWithLookup(cliConfigPath string, cliConfigPathSet bool, lookup func(string) (string, bool), statPath func(string) (os.FileInfo, error), defaultSearchPaths []string) (path string, source string, err error) {
+	if cliConfigPathSet {
+		path = strings.TrimSpace(cliConfigPath)
+		if path == "" {
+			return "", "", fmt.Errorf("--config requires a non-empty path")
+		}
+		if _, statErr := statPath(path); statErr != nil {
+			if os.IsNotExist(statErr) {
+				return "", "", fmt.Errorf("config file not found: %s", path)
+			}
+			return "", "", fmt.Errorf("cannot access config file %s: %w", path, statErr)
+		}
+		return path, "flag", nil
+	}
+
+	if raw, ok := lookup("AUDITA_CONFIG"); ok {
+		path = strings.TrimSpace(raw)
+		if path == "" {
+			return "", "", fmt.Errorf("AUDITA_CONFIG must not be empty")
+		}
+		if _, statErr := statPath(path); statErr != nil {
+			if os.IsNotExist(statErr) {
+				return "", "", fmt.Errorf("config file not found: %s", path)
+			}
+			return "", "", fmt.Errorf("cannot access config file %s: %w", path, statErr)
+		}
+		return path, "env", nil
+	}
+
+	for _, defaultPath := range defaultSearchPaths {
+		if _, statErr := statPath(defaultPath); statErr == nil {
+			return defaultPath, "default", nil
+		} else if !os.IsNotExist(statErr) {
+			return "", "", fmt.Errorf("cannot access config file %s: %w", defaultPath, statErr)
+		}
+	}
+	return "", "", nil
+}

internal/core/config/effective_config_test.go

@@ -0,0 +1,163 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestResolveConfigPathWithLookupMatrix(t *testing.T) {
+	statFor := func(existing map[string]bool) func(string) (os.FileInfo, error) {
+		return func(path string) (os.FileInfo, error) {
+			if existing[path] {
+				return nil, nil
+			}
+			return nil, os.ErrNotExist
+		}
+	}
+
+	tests := []struct {
+		name               string
+		cliPath            string
+		cliPathSet         bool
+		lookup             func(string) (string, bool)
+		stat               func(string) (os.FileInfo, error)
+		defaultSearchPaths []string
+		wantPath           string
+		wantSource         string
+		wantErrContains    string
+	}{
+		{
+			name:       "explicit config path",
+			cliPath:    "/tmp/explicit.yml",
+			cliPathSet: true,
+			lookup:     func(string) (string, bool) { return "", false },
+			stat:       statFor(map[string]bool{"/tmp/explicit.yml": true}),
+			defaultSearchPaths: []string{
+				"/usr/local/etc/audita/config.yml",
+				"/etc/audita/config.yml",
+			},
+			wantPath:   "/tmp/explicit.yml",
+			wantSource: "flag",
+		},
+		{
+			name:       "env config path",
+			cliPathSet: false,
+			lookup: func(key string) (string, bool) {
+				if key == "AUDITA_CONFIG" {
+					return "/tmp/from-env.yml", true
+				}
+				return "", false
+			},
+			stat:               statFor(map[string]bool{"/tmp/from-env.yml": true}),
+			defaultSearchPaths: []string{"/usr/local/etc/audita/config.yml", "/etc/audita/config.yml"},
+			wantPath:           "/tmp/from-env.yml",
+			wantSource:         "env",
+		},
+		{
+			name:       "default search path",
+			cliPathSet: false,
+			lookup:     func(string) (string, bool) { return "", false },
+			stat: statFor(map[string]bool{
+				"/usr/local/etc/audita/config.yml": true,
+				"/etc/audita/config.yml":           true,
+			}),
+			defaultSearchPaths: []string{"/usr/local/etc/audita/config.yml", "/etc/audita/config.yml"},
+			wantPath:           "/usr/local/etc/audita/config.yml",
+			wantSource:         "default",
+		},
+		{
+			name:       "explicit missing path",
+			cliPath:    "/tmp/missing.yml",
+			cliPathSet: true,
+			lookup:     func(string) (string, bool) { return "", false },
+			stat:       statFor(map[string]bool{}),
+			defaultSearchPaths: []string{
+				"/usr/local/etc/audita/config.yml",
+				"/etc/audita/config.yml",
+			},
+			wantErrContains: "config file not found",
+		},
+		{
+			name:       "missing env path",
+			cliPathSet: false,
+			lookup: func(key string) (string, bool) {
+				if key == "AUDITA_CONFIG" {
+					return "/tmp/missing-from-env.yml", true
+				}
+				return "", false
+			},
+			stat:               statFor(map[string]bool{}),
+			defaultSearchPaths: []string{"/usr/local/etc/audita/config.yml", "/etc/audita/config.yml"},
+			wantErrContains:    "config file not found",
+		},
+		{
+			name:       "missing default paths",
+			cliPathSet: false,
+			lookup:     func(string) (string, bool) { return "", false },
+			stat:       statFor(map[string]bool{}),
+			defaultSearchPaths: []string{
+				"/usr/local/etc/audita/config.yml",
+				"/etc/audita/config.yml",
+			},
+			wantPath:   "",
+			wantSource: "",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			gotPath, gotSource, err := resolveConfigPathWithLookup(tc.cliPath, tc.cliPathSet, tc.lookup, tc.stat, tc.defaultSearchPaths)
+			if tc.wantErrContains != "" {
+				if err == nil || !strings.Contains(err.Error(), tc.wantErrContains) {
+					t.Fatalf("expected error containing %q, got %v", tc.wantErrContains, err)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if gotPath != tc.wantPath || gotSource != tc.wantSource {
+				t.Fatalf("unexpected result: got path=%q source=%q, want path=%q source=%q", gotPath, gotSource, tc.wantPath, tc.wantSource)
+			}
+		})
+	}
+}
+
+func TestLoadEffectiveConfigWithLookupAppliesDefaultsFileThenEnv(t *testing.T) {
+	tempDir := t.TempDir()
+	configPath := filepath.Join(tempDir, "config.yml")
+	configYAML := "version: 1\nllm:\n  proposal:\n    model: file-model\n"
+	if err := os.WriteFile(configPath, []byte(configYAML), 0o644); err != nil {
+		t.Fatalf("write config file: %v", err)
+	}
+
+	lookup := func(key string) (string, bool) {
+		switch key {
+		case "AUDITA_CONFIG":
+			return configPath, true
+		case "AUDITA_MODEL":
+			return "env-model", true
+		default:
+			return "", false
+		}
+	}
+
+	result, err := loadEffectiveConfigWithLookup("", false, lookup, os.Stat, DefaultConfigSearchPaths)
+	if err != nil {
+		t.Fatalf("loadEffectiveConfigWithLookup error: %v", err)
+	}
+	if result.ConfigPath != configPath {
+		t.Fatalf("unexpected config path: %q", result.ConfigPath)
+	}
+	if result.ConfigSource != "env" {
+		t.Fatalf("unexpected config source: %q", result.ConfigSource)
+	}
+	if result.ConfigVersion == nil || *result.ConfigVersion != SupportedFileConfigVersion {
+		t.Fatalf("unexpected config version: %#v", result.ConfigVersion)
+	}
+	if result.Config.PrimaryLLM.Model != "env-model" {
+		t.Fatalf("expected env override to win over file value, got %q", result.Config.PrimaryLLM.Model)
+	}
+}