fix(graphql): skip issues that Linear reports as not found

backend/helpers/pluginhelper/api/graphql_collector.go

@@ -348,8 +348,16 @@ func (collector *GraphqlCollector) HasError() bool {
 	return len(collector.workerErrors) > 0
 }
 
+// isIgnorableGraphqlQueryError reports whether err means the queried issue no
+// longer exists upstream, so its children can be skipped. GitHub and Linear
+// word this differently.
 func isIgnorableGraphqlQueryError(err error) bool {
-	return err != nil && strings.Contains(err.Error(), "Could not resolve to an Issue")
+	if err == nil {
+		return false
+	}
+	msg := err.Error()
+	return strings.Contains(msg, "Could not resolve to an Issue") ||
+		strings.Contains(msg, "Entity not found: Issue")
 }
 
 var _ plugin.SubTask = (*GraphqlCollector)(nil)

backend/helpers/pluginhelper/api/graphql_collector_test.go

@@ -26,6 +26,8 @@ import (
 
 func TestIsIgnorableGraphqlQueryError(t *testing.T) {
 	assert.True(t, isIgnorableGraphqlQueryError(errors.New("Could not resolve to an Issue with the number of 17.")))
+	assert.True(t, isIgnorableGraphqlQueryError(errors.New("Entity not found: Issue")))
+	assert.False(t, isIgnorableGraphqlQueryError(errors.New("Entity not found: Team")))
 	assert.False(t, isIgnorableGraphqlQueryError(errors.New("some other graphql error")))
 	assert.False(t, isIgnorableGraphqlQueryError(nil))
 }

backend/plugins/linear/tasks/comment_collector.go

@@ -130,8 +130,7 @@ func CollectComments(taskCtx plugin.SubTaskContext) errors.Error {
 			return query, variables, nil
 		},
 		GetPageInfo: func(iQuery interface{}, args *helper.GraphqlCollectorArgs) (*helper.GraphqlQueryPageInfo, error) {
-			query := iQuery.(*GraphqlQueryCommentWrapper)
-			return query.Issue.Comments.PageInfo, nil
+			return commentsPageInfo(iQuery.(*GraphqlQueryCommentWrapper)), nil
 		},
 		ResponseParser: func(queryWrapper interface{}) (messages []json.RawMessage, err errors.Error) {
 			query := queryWrapper.(*GraphqlQueryCommentWrapper)

backend/plugins/linear/tasks/issue_history_collector.go

@@ -115,8 +115,7 @@ func CollectIssueHistory(taskCtx plugin.SubTaskContext) errors.Error {
 			return query, variables, nil
 		},
 		GetPageInfo: func(iQuery interface{}, args *helper.GraphqlCollectorArgs) (*helper.GraphqlQueryPageInfo, error) {
-			query := iQuery.(*GraphqlQueryHistoryWrapper)
-			return query.Issue.History.PageInfo, nil
+			return historyPageInfo(iQuery.(*GraphqlQueryHistoryWrapper)), nil
 		},
 		ResponseParser: func(queryWrapper interface{}) (messages []json.RawMessage, err errors.Error) {
 			query := queryWrapper.(*GraphqlQueryHistoryWrapper)

backend/plugins/linear/tasks/page_info_test.go

@@ -0,0 +1,48 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements.  See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to You under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package tasks
+
+import (
+	"testing"
+
+	helper "github.com/apache/devlake/helpers/pluginhelper/api"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// A deleted issue comes back as an empty `issue` object: the collector
+// skips its "Entity not found: Issue" error, but must not then fail on the
+// missing page info.
+func TestPageInfo_DeletedIssueEndsPagination(t *testing.T) {
+	comments := commentsPageInfo(&GraphqlQueryCommentWrapper{})
+	require.NotNil(t, comments)
+	assert.False(t, comments.HasNextPage)
+
+	history := historyPageInfo(&GraphqlQueryHistoryWrapper{})
+	require.NotNil(t, history)
+	assert.False(t, history.HasNextPage)
+}
+
+func TestPageInfo_KeepsLinearPagination(t *testing.T) {
+	query := &GraphqlQueryCommentWrapper{}
+	query.Issue.Comments.PageInfo = &helper.GraphqlQueryPageInfo{EndCursor: "c1", HasNextPage: true}
+
+	pageInfo := commentsPageInfo(query)
+	assert.True(t, pageInfo.HasNextPage)
+	assert.Equal(t, "c1", pageInfo.EndCursor)
+}

backend/plugins/linear/tasks/shared.go

@@ -22,9 +22,28 @@ import (
 
 	"github.com/apache/devlake/core/dal"
 	"github.com/apache/devlake/core/models/domainlayer/ticket"
+	helper "github.com/apache/devlake/helpers/pluginhelper/api"
 	"github.com/apache/devlake/plugins/linear/models"
 )
 
+// An issue deleted in Linear returns an empty `issue` object with no page
+// info. The collector skips that error, so treat the issue as its own last
+// page instead of failing on the missing page info.
+func pageInfoOrLast(pageInfo *helper.GraphqlQueryPageInfo) *helper.GraphqlQueryPageInfo {
+	if pageInfo == nil {
+		return &helper.GraphqlQueryPageInfo{HasNextPage: false}
+	}
+	return pageInfo
+}
+
+func commentsPageInfo(query *GraphqlQueryCommentWrapper) *helper.GraphqlQueryPageInfo {
+	return pageInfoOrLast(query.Issue.Comments.PageInfo)
+}
+
+func historyPageInfo(query *GraphqlQueryHistoryWrapper) *helper.GraphqlQueryPageInfo {
+	return pageInfoOrLast(query.Issue.History.PageInfo)
+}
+
 // issuesToCollectChildrenClauses builds the cursor clauses that drive per-issue
 // child collection (comments, history). When `since` is non-nil (an incremental
 // run), it restricts the sweep to issues updated since the last successful