Ghostscript is not initialized correctly when enabling via portal properties

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.3.X, Master
• Fix Version/s: 7.0.X, 7.1.10 DXP FP26, 7.1.10.7 SP7, 7.1.X, 7.2.10 DXP FP15, 7.2.X, 7.3.10.3 DXP SP3, 7.3.X, 7.4.13 DXP GA1, Master
• Component/s: Documents & Media
• Labels:
  • ee-ts
  • liferay-dxp-71-sp7
  • liferay-dxp-73-sp3
  • liferay-fix-pack-dxp-3-7310
  • liferay-fixpack-dxp-15-7210
  • liferay-fixpack-dxp-26-7110
  • liferay-fixpack-dxp-3-7310
• Branch Version/s:
  7.3.x, 7.2.x, 7.1.x, 7.0.x
• Backported to Branch:
  Committed
• Story Points: 1
• Fix Priority: 3
• Sprint: LIMA | QA Sprint 13
• Git Pull Request: https://github.com/liferay-lima/liferay-portal/pull/2240
• QA Test Name:
  • manual

Steps to Reproduce:
1. Install Ghostscript and Imagemagick
2. Put the following in portal-ext.properties (updating the OS and paths as necessary):

imagemagick.enabled=true
imagemagick.global.search.path[unix]=/usr/local/bin:/usr/local/share/ghostscript/fonts:/usr/local/share/fonts/urw-fonts

3. Start the portal
4. Enable debug logging on the com.liferay.portal.image package
5. Go to Menu - Content & Data - Documents and Media
6. Upload a PDF
7. Check for preview

Expected result
Preview is created

Actual result
Exception is thrown:

INFO  [liferay/document_library_pdf_processor-2][GhostscriptImpl:72] Executing command 'null -dBATCH -dSAFER -dNOPAUSE -dNOPROMPT -sFONTPATH=null -sDEVICE=png16m -sOutputFile=/opt/liferay/tomcat/temp/liferay/document_preview/28000.1.0-%d.png -dPDFFitPage -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -r300 -dDEVICEWIDTH=1000 -dDEVICEHEIGHT=1294 /opt/liferay/tomcat/temp/20210825135415890THMMLYYD '
2021-08-25 13:54:16.039 WARN  [liferay/document_library_pdf_processor-2][BaseProcessorMessageListener:40] Unable to process file version 28001
2021-08-25 13:54:16.040 DEBUG [liferay/document_library_pdf_processor-2][BaseProcessorMessageListener:46] java.lang.NullPointerException
java.lang.NullPointerException
	at java.base/java.lang.ProcessBuilder.start(ProcessBuilder.java:1090)
	at java.base/java.lang.ProcessBuilder.start(ProcessBuilder.java:1071)
	at com.liferay.petra.process.ProcessUtil.execute(ProcessUtil.java:55)
	at com.liferay.portal.image.GhostscriptImpl.execute(GhostscriptImpl.java:75)
	at com.liferay.portal.kernel.image.GhostscriptUtil.execute(GhostscriptUtil.java:26)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl._generateImagesGS(PDFProcessorImpl.java:548)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl._generateImagesGS(PDFProcessorImpl.java:486)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl._generateImagesGS(PDFProcessorImpl.java:644)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl._generateImages(PDFProcessorImpl.java:471)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl._generateImages(PDFProcessorImpl.java:427)
	at com.liferay.portlet.documentlibrary.util.PDFProcessorImpl.generateImages(PDFProcessorImpl.java:112)
	at com.liferay.document.library.kernel.util.PDFProcessorUtil.generateImages(PDFProcessorUtil.java:34)
	at com.liferay.portlet.documentlibrary.messaging.PDFProcessorMessageListener.generate(PDFProcessorMessageListener.java:30)
	at com.liferay.portlet.documentlibrary.messaging.BaseProcessorMessageListener.doReceive(BaseProcessorMessageListener.java:36)
	at com.liferay.portal.kernel.messaging.BaseMessageListener.doReceive(BaseMessageListener.java:48)
	at com.liferay.portal.kernel.messaging.BaseMessageListener.receive(BaseMessageListener.java:34)
	at com.liferay.portal.kernel.messaging.InvokerMessageListener.receive(InvokerMessageListener.java:74)
	at com.liferay.portal.messaging.internal.SerialDestination$1.run(SerialDestination.java:59)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:829)