TextToPdfContentTransformer ignores PAGE_LIMIT

[Fikili]

Fix: Expose Configurable Page Limit for XML to PDF Transformations

Summary

There is a problem with transforming and rendering large XML files (mimetype: text/xml) exceeding 100 MB.
When such files are viewed in Alfresco Share, the generated PDF rendition causes performance issues:

• In Chrome, the browser tab crashes.
• In Firefox, the browser and sometimes the entire system become unresponsive.

The Share UI uses PDF.js to display renditions, which struggles with extremely large PDFs generated from large XML sources.

---

Used Transformers

By default, the Misc T-Engine handles the transformation from text/xml → application/pdf:

🔗 misc_engine_config.json#L67-L76

There is also a LibreOffice transformer capable of performing this transformation, but it has priority 110 and is therefore skipped:

🔗 libreoffice_engine_config.json#L226

---

Implementation Details

The transformation logic is implemented in: TextToPdfContentTransformer.java

This class supports a pageLimit option defined in textToPdfOptions.
However, the pageLimit cannot currently be configured via YAML or environment variables because no configuration mapping exists.

There is a configuration example for other PDF-related options such as:

@Value("${transform.core.misc.pdfBox.defaultFont:NotoSans-Regular}")
private String pdfBoxDefaultFont;

Solution

The issue was resolved by exposing the pageLimit property as a configurable option in the TextToPdfContentTransformer class.

A simplified example of the fix:

@Value("${transform.core.misc.textToPdfOptions.pageLimit:1000}")
private int configuredDefaultPageLimit;
...
int pageLimit = configuredDefaultPageLimit;

Then two YAML configuration files were updated to include the new property:

• engines/misc/src/main/resources/application-default.yaml
• engines/aio/src/main/resources/application-default.yaml

Added configuration block:

textToPdfOptions:
  pageLimit: ${MISC_PAGE_LIMIT:1000}

Pull Request

I am currently unable to build the project fully due to missing LibreOffice libraries. Once the build issues are resolved, I can create a Pull Request with the fix.

[Fikili]

Tested on alfresco-transform-core-aio-5.2.1.jar but the latest version doesn't have this option either: https://github.com/Alfresco/alfresco-transform-core/blob/master/engines/misc/src/main/java/org/alfresco/transform/misc/transformers/TextToPdfContentTransformer.java