feat: new output.formats file configuration syntax (#4521)

.golangci.next.reference.yml

@@ -59,15 +59,25 @@ run:
 
 # output configuration options
 output:
-  # Format: colored-line-number|line-number|json|colored-tab|tab|checkstyle|code-climate|junit-xml|github-actions|teamcity
-  #
-  # Multiple can be specified by separating them by comma, output can be provided
-  # for each of them by separating format name and path by colon symbol.
+  # The formats used to render issues.
+  # Format: `colored-line-number`, `line-number`, `json`, `colored-tab`, `tab`, `checkstyle`, `code-climate`, `junit-xml`, `github-actions`, `teamcity`
   # Output path can be either `stdout`, `stderr` or path to the file to write to.
-  # Example: "checkstyle:report.xml,json:stdout,colored-line-number"
   #
-  # Default: colored-line-number
-  format: json
+  # For the CLI flag (`--out-format`), multiple formats can be specified by separating them by comma.
+  # The output can be specified for each of them by separating format name and path by colon symbol.
+  # Example: "--out-format=checkstyle:report.xml,json:stdout,colored-line-number"
+  # The CLI flag (`--out-format`) override the configuration file.
+  #
+  # Default:
+  #   formats:
+  #     - format: colored-line-number
+  #       path: stdout
+  formats:
+    - format: json
+      path: stderr
+    - format: checkstyle
+      path: report.xml
+    - format: colored-line-number
 
   # Print lines of code with issue.
   # Default: true

jsonschema/golangci.next.jsonschema.json

@@ -451,15 +451,42 @@
       "type": "object",
       "additionalProperties": false,
       "properties": {
-        "format": {
-          "description": "Output format to use.",
-          "pattern": "^(,?(colored-line-number|line-number|json|colored-tab|tab|checkstyle|code-climate|junit-xml|github-actions|teamcity)(:[^,]+)?)+$",
-          "default": "colored-line-number",
-          "examples": [
-            "colored-line-number",
-            "checkstyle:report.json,colored-line-number",
-            "line-number:golangci-lint.out,colored-line-number:stdout"
-          ]
+        "formats": {
+          "description": "Output formats to use.",
+          "type": "array",
+          "items": {
+            "type": "object",
+            "additionalProperties": false,
+            "properties": {
+              "path": {
+                "default": "stdout",
+                "anyOf": [
+                  {
+                    "enum": [ "stdout", "stderr" ]
+                  },
+                  {
+                    "type": "string"
+                  }
+                ]
+              },
+              "format": {
+                "default": "colored-line-number",
+                "enum": [
+                  "colored-line-number",
+                  "line-number",
+                  "json",
+                  "colored-tab",
+                  "tab",
+                  "checkstyle",
+                  "code-climate",
+                  "junit-xml",
+                  "github-actions",
+                  "teamcity"
+                ]
+              }
+            },
+            "required": ["format"]
+          }
         },
         "print-issued-lines": {
           "description": "Print lines of code with issue.",

pkg/commands/flagsets.go

@@ -63,8 +63,8 @@ func setupRunFlagSet(v *viper.Viper, fs *pflag.FlagSet) {
 }
 
 func setupOutputFlagSet(v *viper.Viper, fs *pflag.FlagSet) {
-	internal.AddFlagAndBind(v, fs, fs.String, "out-format", "output.format", config.OutFormatColoredLineNumber,
-		color.GreenString(fmt.Sprintf("Format of output: %s", strings.Join(config.OutFormats, "|"))))
+	internal.AddFlagAndBind(v, fs, fs.String, "out-format", "output.formats", config.OutFormatColoredLineNumber,
+		color.GreenString(fmt.Sprintf("Formats of output: %s", strings.Join(config.AllOutputFormats, "|"))))
 	internal.AddFlagAndBind(v, fs, fs.Bool, "print-issued-lines", "output.print-issued-lines", true,
 		color.GreenString("Print lines of code with issue"))
 	internal.AddFlagAndBind(v, fs, fs.Bool, "print-linter-name", "output.print-linter-name", true,

pkg/config/loader.go

@@ -61,7 +61,10 @@ func (l *Loader) Load() error {
 
 	l.handleGoVersion()
 
-	l.handleDeprecation()
+	err = l.handleDeprecation()
+	if err != nil {
+		return err
+	}
 
 	err = l.handleEnableOnlyOption()
 	if err != nil {
@@ -164,7 +167,7 @@ func (l *Loader) parseConfig() error {
 		var configFileNotFoundError viper.ConfigFileNotFoundError
 		if errors.As(err, &configFileNotFoundError) {
 			// Load configuration from flags only.
-			err = l.viper.Unmarshal(l.cfg)
+			err = l.viper.Unmarshal(l.cfg, customDecoderHook())
 			if err != nil {
 				return fmt.Errorf("can't unmarshal config by viper (flags): %w", err)
 			}
@@ -181,7 +184,7 @@ func (l *Loader) parseConfig() error {
 	}
 
 	// Load configuration from all sources (flags, file).
-	if err := l.viper.Unmarshal(l.cfg, fileDecoderHook()); err != nil {
+	if err := l.viper.Unmarshal(l.cfg, customDecoderHook()); err != nil {
 		return fmt.Errorf("can't unmarshal config by viper (flags, file): %w", err)
 	}
 
@@ -279,28 +282,47 @@ func (l *Loader) handleGoVersion() {
 	}
 }
 
-func (l *Loader) handleDeprecation() {
+func (l *Loader) handleDeprecation() error {
+	// Deprecated since v1.57.0
 	if len(l.cfg.Run.SkipFiles) > 0 {
 		l.warn("The configuration option `run.skip-files` is deprecated, please use `issues.exclude-files`.")
 		l.cfg.Issues.ExcludeFiles = l.cfg.Run.SkipFiles
 	}
 
+	// Deprecated since v1.57.0
 	if len(l.cfg.Run.SkipDirs) > 0 {
 		l.warn("The configuration option `run.skip-dirs` is deprecated, please use `issues.exclude-dirs`.")
 		l.cfg.Issues.ExcludeDirs = l.cfg.Run.SkipDirs
 	}
 
 	// The 2 options are true by default.
+	// Deprecated since v1.57.0
 	if !l.cfg.Run.UseDefaultSkipDirs {
 		l.warn("The configuration option `run.skip-dirs-use-default` is deprecated, please use `issues.exclude-dirs-use-default`.")
 	}
 	l.cfg.Issues.UseDefaultExcludeDirs = l.cfg.Run.UseDefaultSkipDirs && l.cfg.Issues.UseDefaultExcludeDirs
 
 	// The 2 options are false by default.
+	// Deprecated since v1.57.0
 	if l.cfg.Run.ShowStats {
 		l.warn("The configuration option `run.show-stats` is deprecated, please use `output.show-stats`")
 	}
 	l.cfg.Output.ShowStats = l.cfg.Run.ShowStats || l.cfg.Output.ShowStats
+
+	// Deprecated since v1.57.0
+	if l.cfg.Output.Format != "" {
+		l.warn("The configuration option `output.format` is deprecated, please use `output.formats`")
+
+		var f OutputFormats
+		err := f.UnmarshalText([]byte(l.cfg.Output.Format))
+		if err != nil {
+			return fmt.Errorf("unmarshal output format: %w", err)
+		}
+
+		l.cfg.Output.Formats = f
+	}
+
+	return nil
 }
 
 func (l *Loader) handleEnableOnlyOption() error {
@@ -332,13 +354,13 @@ func (l *Loader) warn(format string) {
 	l.log.Warnf(format)
 }
 
-func fileDecoderHook() viper.DecoderConfigOption {
+func customDecoderHook() viper.DecoderConfigOption {
 	return viper.DecodeHook(mapstructure.ComposeDecodeHookFunc(
 		// Default hooks (https://github.com/spf13/viper/blob/518241257478c557633ab36e474dfcaeb9a3c623/viper.go#L135-L138).
 		mapstructure.StringToTimeDurationHookFunc(),
 		mapstructure.StringToSliceHookFunc(","),
 
-		// Needed for forbidigo.
+		// Needed for forbidigo, and output.formats.
 		mapstructure.TextUnmarshallerHookFunc(),
 	))
 }

pkg/config/output.go

@@ -21,7 +21,7 @@ const (
 	OutFormatTeamCity          = "teamcity"
 )
 
-var OutFormats = []string{
+var AllOutputFormats = []string{
 	OutFormatColoredLineNumber,
 	OutFormatLineNumber,
 	OutFormatJSON,
@@ -35,14 +35,17 @@ var OutFormats = []string{
 }
 
 type Output struct {
-	Format          string   `mapstructure:"format"`
-	PrintIssuedLine bool     `mapstructure:"print-issued-lines"`
-	PrintLinterName bool     `mapstructure:"print-linter-name"`
-	UniqByLine      bool     `mapstructure:"uniq-by-line"`
-	SortResults     bool     `mapstructure:"sort-results"`
-	SortOrder       []string `mapstructure:"sort-order"`
-	PathPrefix      string   `mapstructure:"path-prefix"`
-	ShowStats       bool     `mapstructure:"show-stats"`
+	Formats         OutputFormats `mapstructure:"formats"`
+	PrintIssuedLine bool          `mapstructure:"print-issued-lines"`
+	PrintLinterName bool          `mapstructure:"print-linter-name"`
+	UniqByLine      bool          `mapstructure:"uniq-by-line"`
+	SortResults     bool          `mapstructure:"sort-results"`
+	SortOrder       []string      `mapstructure:"sort-order"`
+	PathPrefix      string        `mapstructure:"path-prefix"`
+	ShowStats       bool          `mapstructure:"show-stats"`
+
+	// Deprecated: use Formats instead.
+	Format string `mapstructure:"format"`
 }
 
 func (o *Output) Validate() error {
@@ -64,5 +67,46 @@ func (o *Output) Validate() error {
 		}
 	}
 
+	for _, format := range o.Formats {
+		err := format.Validate()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+type OutputFormat struct {
+	Format string `mapstructure:"format"`
+	Path   string `mapstructure:"path"`
+}
+
+func (o *OutputFormat) Validate() error {
+	if o.Format == "" {
+		return errors.New("the format is required")
+	}
+
+	if !slices.Contains(AllOutputFormats, o.Format) {
+		return fmt.Errorf("unsupported output format %q", o.Format)
+	}
+
+	return nil
+}
+
+type OutputFormats []OutputFormat
+
+func (p *OutputFormats) UnmarshalText(text []byte) error {
+	formats := strings.Split(string(text), ",")
+
+	for _, item := range formats {
+		format, path, _ := strings.Cut(item, ":")
+
+		*p = append(*p, OutputFormat{
+			Path:   path,
+			Format: format,
+		})
+	}
+
 	return nil
 }

pkg/config/output_test.go

@@ -81,6 +81,86 @@ func TestOutput_Validate_error(t *testing.T) {
 			},
 			expected: `the sort-order name "linter" is repeated several times`,
 		},
+		{
+			desc: "unsupported format",
+			settings: &Output{
+				Formats: []OutputFormat{
+					{
+						Format: "test",
+					},
+				},
+			},
+			expected: `unsupported output format "test"`,
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			err := test.settings.Validate()
+			require.EqualError(t, err, test.expected)
+		})
+	}
+}
+
+func TestOutputFormat_Validate(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		settings *OutputFormat
+	}{
+		{
+			desc: "only format",
+			settings: &OutputFormat{
+				Format: "json",
+			},
+		},
+		{
+			desc: "format and path (relative)",
+			settings: &OutputFormat{
+				Format: "json",
+				Path:   "./example.json",
+			},
+		},
+		{
+			desc: "format and path (absolute)",
+			settings: &OutputFormat{
+				Format: "json",
+				Path:   "/tmp/example.json",
+			},
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			err := test.settings.Validate()
+			require.NoError(t, err)
+		})
+	}
+}
+
+func TestOutputFormat_Validate_error(t *testing.T) {
+	testCases := []struct {
+		desc     string
+		settings *OutputFormat
+		expected string
+	}{
+		{
+			desc:     "empty",
+			settings: &OutputFormat{},
+			expected: "the format is required",
+		},
+		{
+			desc: "unsupported format",
+			settings: &OutputFormat{
+				Format: "test",
+			},
+			expected: `unsupported output format "test"`,
+		},
 	}
 
 	for _, test := range testCases {