Add support for multiple uids in uid_in function

gql/parser.go

@@ -1766,6 +1766,9 @@ L:
 				case IsInequalityFn(function.Name):
 					err = parseIneqArgs(it, function)
 
+				case function.Name == "uid_in":
+					err = parseIneqArgs(it, function)
+
 				default:
 					err = itemInFunc.Errorf("Unexpected character [ while parsing request.")
 				}

worker/task.go

@@ -701,6 +701,7 @@ func (qs *queryState) handleUidPostings(
 			}
 			var key []byte
 			switch srcFn.fnType {
+			//Check with pawan/ashish if this needs any changes
 			case notAFunction, compareScalarFn, hasFn, uidInFn:
 				if q.Reverse {
 					key = x.ReverseKey(q.Attr, q.UidList.Uids[i])
@@ -757,11 +758,12 @@ func (qs *queryState) handleUidPostings(
 					tlist := &pb.List{Uids: []uint64{q.UidList.Uids[i]}}
 					out.UidMatrix = append(out.UidMatrix, tlist)
 				}
+			//Check with Pawan/Ashish what this function do? I suppose itreturns the relevant posting/uid list to append to uid matrix
 			case srcFn.fnType == uidInFn:
 				if i == 0 {
-					span.Annotate(nil, "UidInFn")
+					span.Annotate(nil, "UidInFn") //Check with Pawan/Ashish what does this do?
 				}
-				reqList := &pb.List{Uids: []uint64{srcFn.uidPresent}}
+				reqList := &pb.List{Uids: srcFn.uidsPresent}
 				topts := posting.ListOptions{
 					ReadTs:    args.q.ReadTs,
 					AfterUid:  0,
@@ -1583,7 +1585,7 @@ type functionContext struct {
 	ineqValueToken string
 	n              int
 	threshold      int64
-	uidPresent     uint64
+	uidsPresent    []uint64
 	fname          string
 	fnType         FuncType
 	regex          *cregexp.Regexp
@@ -1816,16 +1818,17 @@ func parseSrcFn(ctx context.Context, q *pb.Query) (*functionContext, error) {
 		}
 		checkRoot(q, fc)
 	case uidInFn:
-		if err = ensureArgsCount(q.SrcFunc, 1); err != nil {
-			return nil, err
-		}
-		fc.uidPresent, err = strconv.ParseUint(q.SrcFunc.Args[0], 0, 64)
-		if err != nil {
-			if e, ok := err.(*strconv.NumError); ok && e.Err == strconv.ErrSyntax {
-				return nil, errors.Errorf("Value %q in %s is not a number",
-					q.SrcFunc.Args[0], q.SrcFunc.Name)
+		//TODO (Anurag) Implement an argsCount for min 1 argument
+		for _, arg := range q.SrcFunc.Args {
+			uidParsed, err := strconv.ParseUint(arg, 0, 64)
+			if err != nil {
+				if e, ok := err.(*strconv.NumError); ok && e.Err == strconv.ErrSyntax {
+					return nil, errors.Errorf("Value %q in %s is not a number",
+						arg, q.SrcFunc.Name)
+				}
+				return nil, err
 			}
-			return nil, err
+			fc.uidsPresent = append(fc.uidsPresent, uidParsed)
 		}
 		checkRoot(q, fc)
 		if fc.isFuncAtRoot {