Initial commit.

2019-09-17 18:39:37 +05:00
commit 3476411569
11 changed files with 1401 additions and 0 deletions
--- a/compose_tree.go
+++ b/compose_tree.go
@@ -0,0 +1,91 @@
+package sec
+
+import (
+	// stdlib
+	"reflect"
+	"strings"
+)
+
+// Composes full tree for every structure member.
+func composeTree(value reflect.Value, prefix string) {
+	typeOf := value.Type()
+
+	// Compose prefix for everything below current field.
+	var curPrefix string
+	if prefix != "" {
+		curPrefix = prefix
+		if !strings.HasSuffix(curPrefix, "_") {
+			curPrefix += "_"
+		}
+	}
+
+	for i := 0; i < value.NumField(); i++ {
+		fieldToProcess := value.Field(i)
+		fieldToProcessType := typeOf.Field(i)
+
+		// If currently processed field - interface, then we should
+		// get underlying value.
+		//if fieldToProcess.Kind() == reflect.Interface {
+		//	fieldToProcess = fieldToProcess.Elem()
+		//}
+
+		// In 99% of cases we will get uninitialized things we should
+		// initialize.
+		switch fieldToProcess.Kind() {
+		case reflect.Ptr, reflect.Map, reflect.Slice, reflect.Chan:
+			if fieldToProcess.IsNil() {
+				printDebug("Field '%s' is nil, initializing new one", fieldToProcessType.Name)
+
+				// We should use only exported fields as unexported aren't
+				// settable using 'reflect' package. Can be possibly solved
+				// using unsafe pointers?
+				if fieldToProcess.CanSet() {
+					fieldToProcess.Set(reflect.New(fieldToProcess.Type().Elem()))
+				} else {
+					printDebug("Field '%s' is unexported and will be ignored", fieldToProcessType.Name)
+					continue
+				}
+				fieldToProcess = fieldToProcess.Elem()
+			}
+		}
+
+		printDebug("Field: '%s', type: %s, (anonymous or embedded: %t)", fieldToProcessType.Name, fieldToProcess.Type().Kind().String(), fieldToProcessType.Anonymous)
+
+		// Dealing with embedded things.
+		if fieldToProcessType.Anonymous {
+			// We should not allow anything other than struct.
+			if fieldToProcess.Kind() != reflect.Struct {
+				printDebug("Field is embedded, but not a struct (%s), which cannot be used", fieldToProcess.Kind().String())
+				continue
+			}
+		}
+
+		if fieldToProcess.Kind() != reflect.Struct && !fieldToProcess.CanSet() {
+			printDebug("Field '%s' can't be set, skipping", fieldToProcessType.Name)
+			continue
+		}
+
+		printDebug("All underlying elements will have prefix '%s'", curPrefix)
+
+		// Hello, I'm recursion and I'm here to make you happy.
+		// I'll be launched only for structures to get their fields.
+		if fieldToProcess.Kind() == reflect.Struct {
+			newElementPrefix := curPrefix
+			if !fieldToProcessType.Anonymous {
+				newElementPrefix = strings.ToUpper(newElementPrefix + typeOf.Field(i).Name)
+			}
+			composeTree(fieldToProcess, newElementPrefix)
+		} else {
+			f := &field{
+				Name:    typeOf.Field(i).Name,
+				EnvVar:  curPrefix + strings.ToUpper(typeOf.Field(i).Name),
+				Pointer: fieldToProcess,
+				Kind:    fieldToProcess.Kind(),
+			}
+
+			parsedTree = append(parsedTree, f)
+
+			printDebug("Field data constructed: %+v", f)
+		}
+	}
+}