Conversation
Before: get_custom_template put each customize_template value into the template text with a plain gsub. A value can be expanded from a tag or a record field, so a `"` in it closed the JSON string it sat in and the rest was read as more template keys. A log sender could add index_patterns, order and aliases and have fluentd PUT that index template with its own credentials. gsub also read backslash sequences such as \0 in the replacement. After: the value is escaped as JSON string content before it is substituted, and the block form of gsub keeps the replacement literal. A value can only become one string in the template. Co-Authored-By: Claude <noreply@anthropic.com> Signed-off-by: Kentaro Hayashi <hayashi@clear-code.com>
kenhys
marked this pull request as ready for review
September 17, 2026 03:24
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
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Before: get_custom_template put each customize_template value into the template text with a plain gsub. A value can be expanded from a tag or a record field, so a
"in it closed the JSON string it sat in and the rest was read as more template keys. A log sender could add index_patterns, order and aliases and have fluentd PUT that index template with its own credentials. gsub also read backslash sequences such as \0 in the replacement.After: the value is escaped as JSON string content before it is substituted, and the block form of gsub keeps the replacement literal. A value can only become one string in the template.