Fix JWT authentication for SELECT queries on foreign tables#107
Merged
temuenz merged 2 commits intopg-fdw:masterfrom Jan 28, 2026
Merged
Conversation
The jwt_token was missing from serializePlanData() and deserializePlanData(), causing SELECT queries on foreign tables to fail with JWT authentication. IMPORT FOREIGN SCHEMA worked because it reads options directly, but SELECT uses the serialized plan data where jwt_token was not included. This fixes the "cannot authenticate" error (line 99) when using JWT auth for queries on foreign tables.
When JWT auth is used, user is NULL. But db2GetSession converts NULL to "". Meanwhile insertconnEntry stores "" as NULL. This caused findconnEntry to fail matching: - Stored: step->uid = NULL - Searching: user = "" - Old code: NULL == "" -> false (no match!) Now both NULL and "" are treated as "empty" and match each other.
Contributor
Author
|
@temuenz Hi Thomas, is it possible you have a look ? Thank you. |
Collaborator
|
I merged your code. Last time I ran the pipeline it all worked. |
temuenz
added a commit
that referenced
this pull request
Jan 28, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Fixes JWT authentication issues that caused SELECT queries on foreign tables to fail while IMPORT FOREIGN SCHEMA worked correctly.
Changes
Add jwt_token to plan serialization/deserialization (
db2PlanForeignModify.c,db2BeginForeignModify.c)jwt_tokenwas missing fromserializePlanData()anddeserializePlanData()Fix connection cache lookup (
db2AllocConnHdl.c)insertconnEntry()stores empty string as NULLdb2GetSession()converts NULL to empty stringfindconnEntry()now treats NULL and empty string as equivalentSymptoms fixed
cannot authenticateerror (line 99) when using JWT auth for SELECTdb2EndTransaction internal error: handle not found in cachePANIC: ERRORDATA_STACK_SIZE exceededTesting