snapshot of https://github.com/cortezaproject/corteza.git (2024.9.x, 2026-09-18; blobs > 131072B omitted)

server/pkg/sass/processor.go

@@ -0,0 +1,259 @@
+package sass
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"io"
+	"path"
+	"regexp"
+	"strings"
+
+	"github.com/bep/godartsass/v2"
+	"github.com/cortezaproject/corteza/server/assets"
+	"github.com/cortezaproject/corteza/server/pkg/logger"
+	"go.uber.org/zap"
+)
+
+const (
+	GeneralTheme = "general"
+	LightTheme   = "light"
+	DarkTheme    = "dark"
+	SectionRoot  = "root"
+	SectionMain  = "main"
+	SectionTheme = "theme"
+)
+
+var (
+	StylesheetCache      = newStylesheetCache()
+	sassVariablesPattern = regexp.MustCompile(`(\$[a-zA-Z_-]+):\s*([^;]+);`)
+)
+
+// DefaultCSS contains css contents from minified-custom.css and custom-css editor content
+func DefaultCSS(log *zap.Logger, customCSS string) string {
+	var strBuilder strings.Builder
+
+	//read css contents from minified-custom.css
+	minifiedCSSFile, err := assets.Files(logger.Default(), "").Open(path.Join("css", "minified-custom.css"))
+	if err != nil {
+		log.Error("failed to open minified-custom.css file", zap.Error(err))
+	}
+
+	reader := bufio.NewReader(minifiedCSSFile)
+	_, err = io.Copy(&strBuilder, reader)
+	if err != nil {
+		log.Error("failed to read css content from minified-custom.css", zap.Error(err))
+	}
+
+	if customCSS != "" {
+		strBuilder.WriteString(customCSS)
+	}
+
+	processedCSS := strBuilder.String()
+
+	StylesheetCache.Set("default-theme", processedCSS)
+
+	return processedCSS
+}
+
+func Transpile(transpiler *godartsass.Transpiler, log *zap.Logger, themeID, themeSASS, customCSS, sassDirPath string) (err error) {
+	// process root section
+	err = processSass(transpiler, log, SectionRoot, themeID, themeSASS, "", sassDirPath)
+	if err != nil {
+		return err
+	}
+
+	// process main section
+	if themeID == LightTheme {
+		err = processSass(transpiler, log, SectionMain, themeID, themeSASS, customCSS, sassDirPath)
+		if err != nil {
+			return err
+		}
+	}
+
+	//process theme section
+	err = processSass(transpiler, log, SectionTheme, themeID, themeSASS, customCSS, sassDirPath)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func processSass(transpiler *godartsass.Transpiler, log *zap.Logger, section, themeID, themeSASS, customCSS, sassDirPath string) (err error) {
+	var (
+		stringsBuilder         strings.Builder
+		isCustomCssSyntaxValid bool
+	)
+
+	// add theme-mode variable to the top of the section
+	stringsBuilder.WriteString(fmt.Sprintf("$theme-mode: %s;\n", themeID))
+
+	if themeSASS != "" {
+		err = jsonToSass(themeSASS, &stringsBuilder)
+		if err != nil {
+			log.Error("failed to unmarshal branding sass variables", zap.Error(err))
+			return err
+		}
+	}
+
+	if customCSS != "" {
+		_, err = transpileSass(transpiler, customCSS)
+		if err != nil {
+			log.Error("sass compilation for custom css failed", zap.Error(err))
+		} else {
+			isCustomCssSyntaxValid = true
+			// Get SASS variables from the custom CSS editor and give them precedence over branding variables
+			customVariables := sassVariablesPattern.FindAllString(customCSS, -1)
+			for _, customVariable := range customVariables {
+				stringsBuilder.WriteString(fmt.Sprintf("%s \n", customVariable))
+			}
+		}
+	}
+
+	//Save branding sass variables to cache
+	sassVariables, err := readSassFiles(log, "scss/variables")
+	if err != nil {
+		return err
+	}
+	stringsBuilder.WriteString(sassVariables)
+	StylesheetCache.Set("sass", stringsBuilder.String())
+
+	// start processing a section
+	sassSection, err := readSassFiles(log, path.Join("scss", section))
+	if err != nil {
+		return err
+	}
+	stringsBuilder.WriteString(StylesheetCache.Get("sass"))
+	stringsBuilder.WriteString(sassSection)
+
+	// when a user provides sets WEBAPP_SCSS_DIR_PATH environment variable
+	if sassDirPath != "" {
+		customSass, err := readSassFiles(log, sassDirPath)
+		if err != nil {
+			return err
+		}
+		stringsBuilder.WriteString(customSass)
+	}
+
+	if customCSS != "" && isCustomCssSyntaxValid {
+		//Custom CSS editor selector block
+		selectorBlock := sassVariablesPattern.ReplaceAllString(customCSS, "")
+		stringsBuilder.WriteString(selectorBlock)
+	}
+
+	transpiledCss, err := transpileSass(transpiler, stringsBuilder.String())
+	if err != nil {
+		log.Error("sass compilation failure", zap.Error(err))
+	}
+
+	// in case of sass error in custom css sass compilation,
+	// use compiled css from branding sass and append custom css value to it
+	if !isCustomCssSyntaxValid {
+		stringsBuilder.Reset()
+		stringsBuilder.WriteString(transpiledCss)
+		stringsBuilder.WriteString(customCSS)
+
+		// append un-compiled custom css content to transpiled css
+		transpiledCss = stringsBuilder.String()
+	}
+
+	//save the transpiled css to stylesheet cache
+	sectionKey := fmt.Sprintf("%s-%s", section, themeID)
+	StylesheetCache.Set(sectionKey, transpiledCss)
+
+	return nil
+}
+
+// transpileSass computes sass to css by the transpiler
+func transpileSass(transpiler *godartsass.Transpiler, sass string) (string, error) {
+	args := godartsass.Args{
+		Source: sass,
+	}
+	execute, err := transpiler.Execute(args)
+	if err != nil {
+		return "", err
+	}
+
+	return execute.CSS, nil
+}
+
+func DartSassTranspiler(log *zap.Logger) *godartsass.Transpiler {
+	transpiler, err := godartsass.Start(godartsass.Options{
+		DartSassEmbeddedFilename: "sass",
+	})
+
+	if err != nil {
+		log.Warn("dart sass is not installed in your system", zap.Error(err))
+		return nil
+	}
+
+	return transpiler
+}
+
+// readSassFiles reads SASS contents from provided embedded directory and subdirectories then converts them to a string
+func readSassFiles(log *zap.Logger, dirPath string) (string, error) {
+	var stringsBuilder strings.Builder
+
+	filenames, subDirs, err := assets.DirEntries(dirPath)
+	if err != nil {
+		log.Error(fmt.Sprintf("failed to read assets/src/%s entries", dirPath), zap.Error(err))
+		return "", err
+	}
+
+	if len(filenames) > 0 {
+		err := readSassContents(log, dirPath, filenames, &stringsBuilder)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	if len(subDirs) > 0 {
+		for _, subDir := range subDirs {
+			sassContents, err := readSassFiles(log, path.Join(dirPath, subDir))
+			if err != nil {
+				return "", err
+			}
+			stringsBuilder.WriteString(sassContents)
+		}
+	}
+
+	return stringsBuilder.String(), nil
+}
+
+func readSassContents(log *zap.Logger, dirPath string, filenames []string, stringsBuilder *strings.Builder) error {
+	assetFiles := assets.Files(logger.Default(), "")
+
+	for _, fileName := range filenames {
+		open, err := assetFiles.Open(path.Join(dirPath, fileName))
+		if err != nil {
+			log.Error(fmt.Sprintf("failed to open asset %s file", fileName), zap.Error(err))
+			return err
+		}
+
+		reader := bufio.NewReader(open)
+		_, err = io.Copy(stringsBuilder, reader)
+		if err != nil {
+			log.Error(fmt.Sprintf("failed to copy sass content from %s", fileName), zap.Error(err))
+			return err
+		}
+	}
+
+	return nil
+}
+
+// jsonToSass converts JSON string to SASS variable assignment string
+func jsonToSass(jsonStr string, strBuilder *strings.Builder) error {
+	var colorMap map[string]string
+
+	err := json.Unmarshal([]byte(jsonStr), &colorMap)
+	if err != nil {
+		return err
+	}
+
+	for key, value := range colorMap {
+		strBuilder.WriteString(fmt.Sprintf("$%s: %s;\n", key, value))
+	}
+
+	return nil
+}