X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/e59b78c774872e33b9c69acc196989a0f565bdf4..bcad695db9a1c3aac5807faa153086e653107f51:/sdk/go/arvados/resource_list.go

diff --git a/sdk/go/arvados/resource_list.go b/sdk/go/arvados/resource_list.go
index 14ce098cfc..7f319b4121 100644
--- a/sdk/go/arvados/resource_list.go
+++ b/sdk/go/arvados/resource_list.go
@@ -4,7 +4,10 @@
 
 package arvados
 
-import "encoding/json"
+import (
+	"encoding/json"
+	"fmt"
+)
 
 // ResourceListParams expresses which results are requested in a
 // list/index API.
@@ -27,7 +30,44 @@ type Filter struct {
 	Operand  interface{}
 }
 
-// MarshalJSON encodes a Filter in the form expected by the API.
+// MarshalJSON encodes a Filter to a JSON array.
 func (f *Filter) MarshalJSON() ([]byte, error) {
 	return json.Marshal([]interface{}{f.Attr, f.Operator, f.Operand})
 }
+
+// UnmarshalJSON decodes a JSON array to a Filter.
+func (f *Filter) UnmarshalJSON(data []byte) error {
+	var decoded interface{}
+	err := json.Unmarshal(data, &decoded)
+	if err != nil {
+		return err
+	}
+	switch decoded := decoded.(type) {
+	case string:
+		// Accept "(foo < bar)" as a more obvious way to spell
+		// ["(foo < bar)","=",true]
+		*f = Filter{decoded, "=", true}
+	case []interface{}:
+		if len(decoded) != 3 {
+			return fmt.Errorf("invalid filter %q: must have 3 decoded", data)
+		}
+		attr, ok := decoded[0].(string)
+		if !ok {
+			return fmt.Errorf("invalid filter attr %q", decoded[0])
+		}
+		op, ok := decoded[1].(string)
+		if !ok {
+			return fmt.Errorf("invalid filter operator %q", decoded[1])
+		}
+		operand := decoded[2]
+		switch operand.(type) {
+		case string, float64, []interface{}, nil, bool:
+		default:
+			return fmt.Errorf("invalid filter operand %q", decoded[2])
+		}
+		*f = Filter{attr, op, operand}
+	default:
+		return fmt.Errorf("invalid filter: json decoded as %T instead of array or string", decoded)
+	}
+	return nil
+}