无法在tomcat8 dockerfile上添加server.xml。 xml中的错误

Question

Ok I´m quite lost over here and tried many things unable to solve problem. this is the situation. I´m building a tomcat 8 official image with a dockerfile. the thing is under this image te server.xml file points to port 8080 and I would like to point to port 443. So I enter the container. cat the /conf/server.xml file, copy the content to a local editor (sublime, notepad ++ or visual studio code) change the part 8080 by 443 and also added certificates like this. the rest of the xml files remains the same

<Connector port="443" protocol="HTTP/1.1"
        maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
           clientAuth="false"
           SSLCertificateFile="conf/star.grey.com.crt"
           SSLCertificateKeyFile="conf/server.key"
           SSLVerifyClient="optional"
           SSLProtocol="TLSv1.2"/>

Then I saved the file localy on my editor as server.xml and add this file on same destination of dockerfile in which I add the line: ADD server.xml /conf/server.xml (which overwrites the existing one)

So I have 2 new images alpine:tomcat8 and alpine:tomcat8-with-new-serverxml

I if run a container with the oficial image without any modification, it runs successfully. If i Run a container with the modified image i get now:

-Aug-2018 14:28:56.303 SEVERE [main] org.apache.tomcat.util.digester.Digester.fatalError Parse Fatal Error at line 1 column 1: Content is not allowed in prolog.


org.xml.sax.SAXParseException; systemId: file:/usr/local/tomcat/conf/server.xml; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.
    at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203)

Is the same exact xml that I copied from container from /conf/server.xml. I just modified 443 port and added the certificates.

how come same file now is unrecognized? I tried:

copyng the container content of server.xml in a new file locally, modified the 443 part. save as server.xml with utf-8 ANSI, utf-8 or NO BOM in notepadd ++ , sublime or visual stuio code. And every time I upload the file to the image and container starts I get same issue. How can I solve this? it´s driving me crazy.

I tried the option of entering the container modifying the file and commitin change to new image and this works, but this doesn´t help, since this image is build during a pipeline with jenkins, i can´t login in container during the jenkins pipeline.

PLEASE HELP

thank you

this is what is original on server.xml

 <Connector port="8080" protocol="HTTP/1.1"
           connectionTimeout="20000"
           redirectPort="8443" />

this is what I would like to chang it for:

<Connector port="443" protocol="HTTP/1.1"
           maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
           clientAuth="false"
           SSLCertificateFile="conf/star.grey.com.crt"
           SSLCertificateKeyFile="conf/server.key"
           SSLVerifyClient="optional"
           SSLProtocol="TLSv1.2" />

Also I use the cat -A in server.xml on docker container that is working ok and file saw some "$" characters in some parts. Should I remove them manually? However why If copied from original and they already have those "$" when I edit that file and add it again it give the error that I´m getting? quite conffuging . check image of some part of the original web.xml in container that is running.

Answer 1

Can you open a shell in your new created container and try to cat the server.xml file? Use cat -A to show all the hidden characters.

That error is caused probably by a non-existent file or a character before the beginning of the xml content.

Also, if the only thing you're doing is changing the tomcat's port you have other solutions:

• Expose the port you want when you run the container: -p 443:8080
• Mount the server.xml with your configuration when running the container as a volume -v ./server.xml:/conf/server.xml
• Or if you want to really build your image and change just the port you can do RUN value= cat conf/server.xml && echo "${value//8080/443}" >| conf/server.xml && echo "${value//8080/443}" >| conf/server.xml