Unable to Print Jasper Report in Docker Container with Alpine-based OpenJDK Image
I am encountering an issue while attempting to print a Jasper report within a Docker container using an Alpine-based OpenJDK image. The application runs smoothly when using a non-Alpine base image, but encounters problems when using Alpine-based images.
I am using JasperFillManager.fillReport(String sourceFileName, Map<String, Object> params, Connection connection) method for report printing in java.
Here's my Dockerfile that works fine with a non-Alpine base image:
FROM openjdk:17-jdk-slim
MAINTAINER my-company.com
RUN apt-get update && apt-get install fontconfig libfreetype6 -y && apt-get update
COPY target/classes/static/fonts/*.ttf /usr/local/share/fonts/
RUN fc-cache -fv
COPY target/my-java-app-?.?*.jar .
ENTRYPOINT ["java", "-jar", "/my-java-app-2.0.0.jar"]
EXPOSE 8040
However, when I switch to an Alpine-based OpenJDK image with the following Dockerfile, the reports are not printed and no exceptions are thrown:
FROM bellsoft/liberica-openjdk-alpine:17
MAINTAINER my-company.com
RUN apk update && apk add fontconfig freetype
COPY target/classes/static/fonts/*.ttf /usr/local/share/fonts/
RUN fc-cache -fv
COPY target/my-java-app-?.?*.jar .
ENTRYPOINT ["java", "-jar", "/my-java-app-2.0.0.jar"]
EXPOSE 8040
The application is responsible for printing Jasper reports, and it works fine with a non-Alpine base image. However, when using the Alpine-based OpenJDK image, the reports are not printed, and no exceptions are thrown.
I think the issue is with freetype library which is not allowing me to print the report.
I've ensured that the necessary fonts are copied and cached properly. Is there anything specific I need to configure or install in the Alpine-based image to enable Jasper report printing? Are there any known compatibility issues or additional dependencies required for Jasper printing within Alpine-based images?
Any insights or suggestions would be greatly appreciated. Thank you!
Answers It seems that you have installed the necessary font-related dependencies in your Alpine-based image, similar to what you did in the non-Alpine base image. However, there might be some differences in how font handling is done in Alpine compared to other Linux distributions.
One thing you can try is to ensure that your font files are accessible and properly registered within the Alpine environment. Here are a few steps you can take to troubleshoot the issue:
- Check if the font files are copied to the correct directory in the Alpine image.
- Verify that the font cache is properly generated using
fc-cache -fv. - Ensure that the font configuration is correct in the Alpine environment.
If the above steps don't resolve the issue, there might be some differences in how font handling is done in Alpine compared to other distributions. You can try installing additional font-related packages or libraries that might be required by JasperReports or font rendering in Alpine.
Additionally, you can try enabling debugging or verbose logging in your Java application to see if there are any specific errors or warnings related to font handling during the report generation process.
If you continue to encounter issues, you may also consider reaching out to the Alpine Linux community or the maintainers of the OpenJDK Alpine image for further assistance and guidance on font handling and compatibility issues in Alpine-based environments.
