WIP: updated log level on some log entries and added environment variable expansion for command line and its arguments

task/env/env.go

@@ -0,0 +1,97 @@
+package env
+
+import (
+	"fmt"
+	"gitea.suyono.dev/suyono/wingmate"
+	"regexp"
+	"strings"
+)
+
+var (
+	envCapture     = regexp.MustCompile(`\$+[a-zA-Z_][a-zA-Z0-9_]*|\$+{[a-zA-Z_][a-zA-Z0-9_]*}`)
+	envEsc         = regexp.MustCompile(`^\$\$+[^$]+$`)  // escaped, starts with two or more $ character
+	envRef         = regexp.MustCompile(`^\$([^$]+)$`)   // capture the variable name
+	envRefExplicit = regexp.MustCompile(`^\${([^$]+)}$`) // capture the variable name - explicit
+)
+
+func expandEnv(envMap map[string]string, input string) string {
+	if envEsc.MatchString(input) {
+		return input
+	}
+
+	if envName := envRefExplicit.FindStringSubmatch(input); envName != nil && envName[1] != "" {
+		exVal, ok := envMap[envName[1]]
+		if !ok {
+			return ""
+		}
+		return exVal
+	}
+
+	if envName := envRef.FindStringSubmatch(input); envName != nil && envName[1] != "" {
+		exVal, ok := envMap[envName[1]]
+		if !ok {
+			return ""
+		}
+		return exVal
+	}
+	return input
+
+}
+
+func PatchEnv(existing, new []string) []string {
+	tMap := make(map[string]string)
+	for _, e := range existing {
+		key, value, ok := strings.Cut(e, "=")
+		if !ok {
+			wingmate.Log().Warn().Msgf("removing invalid environment:", e)
+			continue
+		}
+		tMap[key] = value
+	}
+
+	for _, e := range new {
+		key, value, ok := strings.Cut(e, "=")
+		if !ok {
+			wingmate.Log().Warn().Msgf("removing invalid environment:", e)
+			continue
+		}
+
+		if strings.ContainsAny(key, "$") {
+			wingmate.Log().Error().Err(fmt.Errorf("variable name contains $")).Msgf("removing invalid environment:", e)
+			continue
+		}
+
+		value = envCapture.ReplaceAllStringFunc(value, func(rep string) string {
+			return expandEnv(tMap, rep)
+		})
+
+		tMap[key] = value
+	}
+
+	outEnv := make([]string, 0, len(existing))
+	for key, val := range tMap {
+		outEnv = append(outEnv, fmt.Sprintf("%s=%s", key, val))
+	}
+
+	return outEnv
+}
+
+func ExpandEnv(env []string, input []string) []string {
+	envMap := make(map[string]string)
+	for _, e := range env {
+		key, value, ok := strings.Cut(e, "=")
+		if !ok {
+			wingmate.Log().Warn().Msgf("removing bad environment:", e)
+			continue
+		}
+		envMap[key] = value
+	}
+
+	for i, s := range input {
+		s = envCapture.ReplaceAllStringFunc(s, func(rep string) string {
+			return expandEnv(envMap, rep)
+		})
+		input[i] = s
+	}
+	return input
+}