1 files changed, 76 insertions, 4 deletions
diff --git a/pkg/server/env/env.go b/pkg/server/env/env.go
index 2c97669..7aa93d2 100644
--- a/pkg/server/env/env.go
+++ b/pkg/server/env/env.go
@@ -4,12 +4,23 @@ import (
 	"errors"
 	"regexp"
 	"sort"
+	"strings"
 	"sync"
 )
 
 type env struct {
+	// vars
 	m map[string]string
+
+	// forks
+	c map[string]*env
+
+	// key in parent env's map
+	k string
+
 	sync.Mutex
+
+	// parent env
 	p *env
 }
 
@@ -36,23 +47,84 @@ func (e Env) init() {
 	}
 }
 
-func (e Env) Fork() Env {
+func (e Env) Fork(path ...string) Env {
 	t := New()
 	t.p = e.env
+
+	if len(path) > 0 {
+		k := strings.Join(path, ".")
+
+		e.Lock()
+		if e.c == nil {
+			e.c = make(map[string]*env)
+		} else if _, ok := e.c[k]; ok {
+			panic("env fork already exists: " + k)
+		}
+		e.c[k] = t.env
+		e.Unlock()
+
+		t.k = k
+	}
+
 	return t
 }
 
-func (e *env) Find(key string) (string, bool) {
+func (e Env) Detach() {
+	if e.p != nil {
+		e.p.Lock()
+		delete(e.p.c, e.k)
+		e.p.Unlock()
+	}
+}
+
+func (e *env) find(key string) (string, bool, func() (string, bool)) {
 	e.Lock()
 	defer e.Unlock()
 
 	v, ok := e.m[key]
 	if ok {
-		return v, ok
+		return v, ok, nil
+	}
+
+	if e.c != nil {
+		s := strings.Split(key, ".")
+
+		for k := ""; len(s) > 1; s = s[1:] {
+			if k == "" {
+				k = s[0]
+			} else {
+				k += "." + s[0]
+			}
+
+			if c, ok := e.c[k]; ok {
+				return "", false, func() (string, bool) {
+					return c.Find(strings.Join(s[1:], "."))
+				}
+			}
+		}
 	}
 
 	if e.p != nil {
-		return e.p.Find(key)
+		return "", false, func() (string, bool) {
+			return e.p.Find(key)
+		}
+	}
+
+	return "", false, nil
+}
+
+func (e *env) Find(key string) (string, bool) {
+	if key == "" {
+		return "", false
+	}
+
+	v, ok, f := e.find(key)
+	if ok {
+		return v, ok
+	}
+
+	if f != nil {
+		return f()
 	}
 
 	return "", false