Webviewer Server Docker on Heroku - Setting PORT at Runtime

Product: Webviewer Server

Product Version: pdftron/webviewer-server:1.5.8

Please give a brief summary of your issue:
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Heroku assigns ports dynamically at runtime. PDFTron webviewer server exposes a fixed port, 8090. Would appreciate any advice or suggestions on how to dynamically configure the webviewer server port.

Please describe your issue and provide steps to reproduce it:
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Heroku states:

When deploying a container app on Heroku, we require that Dockerfiles are configured to intake the randomly assigned port on a dyno - exposed as the $PORT environmental variable.

However Webviewer Server only exposes 8090:

We’re currently using socat to forward connections to port 8090 but would appreciate any suggestions on how to dynamically configure the port

Please provide a link to a minimal sample where the issue is reproducible:

1 Like

Hi Alex,

I spoke with our WVS developer unfortunately there is no way to dynamically configure the port at runtime.
The port can be configured in the following file within the docker container /usr/local/apache-tomcat/conf/server.xml.
If the port that will be set is available prior to starting the docker container, then you could create your own modified version of the docker container overwriting that file with a copy using the new port.


FROM pdftron/webviewer-server:1.5.8
COPY server.xml /usr/local/apache-tomcat/conf/server.xml

Please let me know if there are any issues.

Best Regards,
Ahmad Moaaz
Software Developer
PDFTron Systems, Inc.