Adding upstream version 2.52.6.

Signed-off-by: Daniel Baumann <daniel@debian.org>

middleware/envvar/envvar.go

@@ -0,0 +1,68 @@
+package envvar
+
+import (
+	"os"
+	"strings"
+
+	"github.com/gofiber/fiber/v2"
+)
+
+// Config defines the config for middleware.
+type Config struct {
+	// ExportVars specifies the environment variables that should export
+	ExportVars map[string]string
+	// ExcludeVars specifies the environment variables that should not export
+	ExcludeVars map[string]string
+}
+
+type EnvVar struct {
+	Vars map[string]string `json:"vars"`
+}
+
+func (envVar *EnvVar) set(key, val string) {
+	envVar.Vars[key] = val
+}
+
+func New(config ...Config) fiber.Handler {
+	var cfg Config
+	if len(config) > 0 {
+		cfg = config[0]
+	}
+
+	return func(c *fiber.Ctx) error {
+		if c.Method() != fiber.MethodGet {
+			return fiber.ErrMethodNotAllowed
+		}
+
+		envVar := newEnvVar(cfg)
+		varsByte, err := c.App().Config().JSONEncoder(envVar)
+		if err != nil {
+			return c.Status(fiber.StatusInternalServerError).SendString(err.Error())
+		}
+		c.Set(fiber.HeaderContentType, fiber.MIMEApplicationJSONCharsetUTF8)
+		return c.Send(varsByte)
+	}
+}
+
+func newEnvVar(cfg Config) *EnvVar {
+	vars := &EnvVar{Vars: make(map[string]string)}
+
+	if len(cfg.ExportVars) > 0 {
+		for key, defaultVal := range cfg.ExportVars {
+			vars.set(key, defaultVal)
+			if envVal, exists := os.LookupEnv(key); exists {
+				vars.set(key, envVal)
+			}
+		}
+	} else {
+		const numElems = 2
+		for _, envVal := range os.Environ() {
+			keyVal := strings.SplitN(envVal, "=", numElems)
+			if _, exists := cfg.ExcludeVars[keyVal[0]]; !exists {
+				vars.set(keyVal[0], keyVal[1])
+			}
+		}
+	}
+
+	return vars
+}