First version

1 files changed, 40 insertions, 0 deletions

diff --git a/envcfg.go b/envcfg.go
new file mode 100644
index 0000000..b91ea13
--- /dev/null
+++ b/envcfg.go
@@ -0,0 +1,40 @@
+// Package envcfg provides environment variable mapping to structs.
+//
+// Can be used to read configuration parameters from the environment.
+//
+// Fields for which environment variables can be found are overwritten, otherwise they are left to their previous
+// value.
+//
+// Can be used, for example, after gcfg to override settings provided in a configuration file.
+package envcfg
+
+import (
+        "errors"
+        "reflect"
+)
+
+const (
+        TAG     = "env"
+        ABS_TAG = "absenv"
+        SEP     = "_"
+)
+
+type node struct {
+        parent     *node
+        value      *reflect.Value
+        properties *reflect.StructField
+}
+
+var ErrInvalidConfigStruct = errors.New("invalid parameter: must map to a struct")
+
+func ReadInto(cfgStruct interface{}) (interface{}, []error) {
+        s := reflect.ValueOf(cfgStruct).Elem()
+
+        if s.Kind() != reflect.Struct {
+                return nil, []error{ErrInvalidConfigStruct}
+        }
+
+        _, errs := setStructFields(node{nil, &s, nil})
+
+        return cfgStruct, errs
+}