Implement List Groups (#133)

* Implement List Groups

* Updating ListGroup's comments and tweaking variable name.

internal/servers/controller/handlers/groups/group_service.go

@@ -43,9 +43,16 @@ func NewService(repo func() (*iam.Repository, error)) (Service, error) {
 
 var _ pbs.GroupServiceServer = Service{}
 
-// CreateGroup is not yet implemented but will implement the interface pbs.GroupServiceServer.
-func (s Service) ListGroups(context.Context, *pbs.ListGroupsRequest) (*pbs.ListGroupsResponse, error) {
-	return nil, status.Error(codes.Unimplemented, "List not enabled for this resource.")
+// ListGroups implements the interface pbs.GroupServiceServer.
+func (s Service) ListGroups(ctx context.Context, req *pbs.ListGroupsRequest) (*pbs.ListGroupsResponse, error) {
+	if err := validateListRequest(req); err != nil {
+		return nil, err
+	}
+	gl, err := s.listFromRepo(ctx, req.GetOrgId())
+	if err != nil {
+		return nil, err
+	}
+	return &pbs.ListGroupsResponse{Items: gl}, nil
 }
 
 // GetGroups implements the interface pbs.GroupServiceServer.
@@ -189,6 +196,22 @@ func (s Service) deleteFromRepo(ctx context.Context, id string) (bool, error) {
 	return rows > 0, nil
 }
 
+func (s Service) listFromRepo(ctx context.Context, orgId string) ([]*pb.Group, error) {
+	repo, err := s.repoFn()
+	if err != nil {
+		return nil, err
+	}
+	gl, err := repo.ListGroups(ctx, orgId)
+	if err != nil {
+		return nil, err
+	}
+	var outGl []*pb.Group
+	for _, g := range gl {
+		outGl = append(outGl, toProto(g))
+	}
+	return outGl, nil
+}
+
 // toDbUpdateMask converts the wire format's FieldMask into a list of strings containing FieldMask paths used
 func toDbUpdateMask(paths []string) ([]string, error) {
 	var dbPaths []string
@@ -299,6 +322,14 @@ func validateDeleteRequest(req *pbs.DeleteGroupRequest) error {
 	return nil
 }
 
+func validateListRequest(req *pbs.ListGroupsRequest) error {
+	badFields := validateAncestors(req)
+	if len(badFields) > 0 {
+		return handlers.InvalidArgumentErrorf("Improperly formatted identifier.", badFields)
+	}
+	return nil
+}
+
 func validId(id, prefix string) bool {
 	if !strings.HasPrefix(id, prefix) {
 		return false

internal/servers/controller/handlers/groups/group_service_test.go

@@ -107,6 +107,78 @@ func TestGet(t *testing.T) {
 	}
 }
 
+func TestList(t *testing.T) {
+	assert, require := assert.New(t), require.New(t)
+	cleanup, conn, _ := db.TestSetup(t, "postgres")
+	t.Cleanup(func() {
+		if err := conn.Close(); err != nil {
+			t.Errorf("Error when closing gorm DB: %v", err)
+		}
+		if err := cleanup(); err != nil {
+			t.Errorf("Error when cleaning up TestSetup: %v", err)
+		}
+	})
+	rw := db.New(conn)
+	wrap := db.TestWrapper(t)
+	repoFn := func() (*iam.Repository, error) {
+		return iam.NewRepository(rw, rw, wrap)
+	}
+	oNoGroups, _ := iam.TestScopes(t, conn)
+	oWithGroups, _ := iam.TestScopes(t, conn)
+	var wantGroups []*pb.Group
+	for i := 0; i < 10; i++ {
+		g := iam.TestGroup(t, conn, oWithGroups.GetPublicId())
+		wantGroups = append(wantGroups, &pb.Group{
+			Id:          g.GetPublicId(),
+			CreatedTime: g.GetCreateTime().GetTimestamp(),
+			UpdatedTime: g.GetUpdateTime().GetTimestamp(),
+		})
+	}
+
+	cases := []struct {
+		name    string
+		req     *pbs.ListGroupsRequest
+		res     *pbs.ListGroupsResponse
+		errCode codes.Code
+	}{
+		{
+			name:    "List Many Group",
+			req:     &pbs.ListGroupsRequest{OrgId: oWithGroups.GetPublicId()},
+			res:     &pbs.ListGroupsResponse{Items: wantGroups},
+			errCode: codes.OK,
+		},
+		{
+			name:    "List No Groups",
+			req:     &pbs.ListGroupsRequest{OrgId: oNoGroups.GetPublicId()},
+			res:     &pbs.ListGroupsResponse{},
+			errCode: codes.OK,
+		},
+		{
+			name:    "Invalid Org Id",
+			req:     &pbs.ListGroupsRequest{OrgId: iam.OrganizationScope.Prefix() + "_this is invalid"},
+			res:     nil,
+			errCode: codes.InvalidArgument,
+		},
+		// TODO: When an org doesn't exist, we should return a 404 instead of an empty list.
+		{
+			name:    "Unfound Org",
+			req:     &pbs.ListGroupsRequest{OrgId: iam.OrganizationScope.Prefix() + "_DoesntExis"},
+			res:     &pbs.ListGroupsResponse{},
+			errCode: codes.OK,
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			s, err := groups.NewService(repoFn)
+			require.NoError(err, "Couldn't create new group service.")
+
+			got, gErr := s.ListGroups(context.Background(), tc.req)
+			assert.Equal(tc.errCode, status.Code(gErr), "ListGroups(%+v) got error %v, wanted %v", tc.req, gErr, tc.errCode)
+			assert.True(proto.Equal(got, tc.res), "ListGroups(%q) got response %q, wanted %q", tc.req, got, tc.res)
+		})
+	}
+}
+
 func TestDelete(t *testing.T) {
 	require := require.New(t)
 	g, repo := createDefaultGroupAndRepo(t)