从Heroku上的Docker容器中访问X-Server
我正在移植一个旧的.NETWebAPI应用程序,以便在Docker容器中的Heroku上运行。我用的是单声道图像 这是我的Dockerfile:从Heroku上的Docker容器中访问X-Server,docker,heroku,mono,Docker,Heroku,Mono,我正在移植一个旧的.NETWebAPI应用程序,以便在Docker容器中的Heroku上运行。我用的是单声道图像 这是我的Dockerfile: FROM mono:latest EXPOSE 5000 ENV PORT 5000 ADD ./ /api WORKDIR /api RUN nuget restore -NonInteractive RUN msbuild webapi.sln /p:Configuration=Release CMD mono /api/MyProject/bin
FROM mono:latest
EXPOSE 5000
ENV PORT 5000
ADD ./ /api
WORKDIR /api
RUN nuget restore -NonInteractive
RUN msbuild webapi.sln /p:Configuration=Release
CMD mono /api/MyProject/bin/Release/MyProject.exe port:$PORT
非常简单,使用最新的Mono映像,复制源代码,恢复NuGet包,构建解决方案并运行它。$PORT环境变量由Heroku设置,对于我的本地开发环境,默认值为5000
除了一个生成PDF报告的特定API控制器外,所有这些都非常有效。该报告由PdfSharp生成,PdfSharp依赖于System.Drawing程序集进行必要的渲染。然而,这意味着对显示器具有依赖性
当我调用该控制器生成报告时,我得到以下错误
Could not open display (X-Server required. Check your DISPLAY environment variable).
我需要访问X服务器才能进行必要的渲染。我尝试了很多方法,但总是遇到这个错误。通过安装Xvfb(虚拟帧缓冲区),一个实现X11显示服务器协议的显示服务器,使其正常工作。您可以查看下面更新的Dockerfile 备注:除了显示服务器之外,让PDFSharp在Mono上运行还有更多问题。我还必须更新apt源代码并安装Microsoft Core字体,因为我生成的报告使用它们。 我还必须使用PDFSharp的修改版本,它知道如何定位字体。幸运的是,我已经做到了: 相关代码如下: 有点黑,你可能需要修改它,以适应你的设置,但它做的工作。只要创建一个MonoRelease构建并引用这个程序集,就可以了 Dockerfile
FROM mono:latest
# Update the sources.list for apt-get so it knows where to download the Microsoft Core fonts.
RUN echo "deb http://gce_debian_mirror.storage.googleapis.com wheezy contrib non-free" >> /etc/apt/sources.list \
&& echo "deb http://gce_debian_mirror.storage.googleapis.com wheezy-updates contrib non-free" >> /etc/apt/sources.list \
&& echo "deb http://security.debian.org/ wheezy/updates contrib non-free" >> /etc/apt/sources.list
# Install Xvfb and the Microsoft core fonts
RUN apt-get update
RUN apt-get install -y xvfb ttf-mscorefonts-installer
# Configure Xvfb as a daemon.
ADD xvfb.init /etc/init.d/xvfb
RUN chmod +x /etc/init.d/xvfb
RUN update-rc.d xvfb defaults
EXPOSE 5000
ENV PORT 5000
ADD ./ /api
WORKDIR /api
RUN nuget restore -NonInteractive
RUN msbuild webapi.sln /p:Configuration=Release
# Start Xvfb and the Web Api
CMD (service xvfb start; export DISPLAY=:10; mono /api/MyProject/bin/Release/MyProject.exe port:$PORT)
xvfb.init
#!/bin/bash
#
# /etc/rc.d/init.d/xvfbd
#
# chkconfig: 345 95 28
# description: Starts/Stops X Virtual Framebuffer server
# processname: Xvfb
#
[ "${NETWORKING}" = "no" ] && exit 0
PROG="/usr/bin/Xvfb"
PROG_OPTIONS=":10 -ac"
PROG_OUTPUT="/tmp/Xvfb.out"
case "$1" in
start)
echo -n "Starting : X Virtual Frame Buffer "
$PROG $PROG_OPTIONS>>$PROG_OUTPUT 2>&1 &
disown -ar
;;
stop)
echo -n "Shutting down : X Virtual Frame Buffer"
killproc $PROG
RETVAL=$?
[ $RETVAL -eq 0 ] && /bin/rm -f /var/lock/subsys/Xvfb/var/run/Xvfb.pid
echo
;;
restart|reload)
$0 stop
$0 start
RETVAL=$?
;;
status)
status Xvfb
RETVAL=$?
;;
*)
echo $"Usage: $0 (start|stop|restart|reload|status)"
exit 1
esac
exit $RETVAL
通过安装Xvfb(虚拟帧缓冲区)使其正常工作,Xvfb是一个实现X11显示服务器协议的显示服务器。您可以查看下面更新的Dockerfile 备注:除了显示服务器之外,让PDFSharp在Mono上运行还有更多问题。我还必须更新apt源代码并安装Microsoft Core字体,因为我生成的报告使用它们。 我还必须使用PDFSharp的修改版本,它知道如何定位字体。幸运的是,我已经做到了: 相关代码如下: 有点黑,你可能需要修改它,以适应你的设置,但它做的工作。只要创建一个MonoRelease构建并引用这个程序集,就可以了 Dockerfile
FROM mono:latest
# Update the sources.list for apt-get so it knows where to download the Microsoft Core fonts.
RUN echo "deb http://gce_debian_mirror.storage.googleapis.com wheezy contrib non-free" >> /etc/apt/sources.list \
&& echo "deb http://gce_debian_mirror.storage.googleapis.com wheezy-updates contrib non-free" >> /etc/apt/sources.list \
&& echo "deb http://security.debian.org/ wheezy/updates contrib non-free" >> /etc/apt/sources.list
# Install Xvfb and the Microsoft core fonts
RUN apt-get update
RUN apt-get install -y xvfb ttf-mscorefonts-installer
# Configure Xvfb as a daemon.
ADD xvfb.init /etc/init.d/xvfb
RUN chmod +x /etc/init.d/xvfb
RUN update-rc.d xvfb defaults
EXPOSE 5000
ENV PORT 5000
ADD ./ /api
WORKDIR /api
RUN nuget restore -NonInteractive
RUN msbuild webapi.sln /p:Configuration=Release
# Start Xvfb and the Web Api
CMD (service xvfb start; export DISPLAY=:10; mono /api/MyProject/bin/Release/MyProject.exe port:$PORT)
xvfb.init
#!/bin/bash
#
# /etc/rc.d/init.d/xvfbd
#
# chkconfig: 345 95 28
# description: Starts/Stops X Virtual Framebuffer server
# processname: Xvfb
#
[ "${NETWORKING}" = "no" ] && exit 0
PROG="/usr/bin/Xvfb"
PROG_OPTIONS=":10 -ac"
PROG_OUTPUT="/tmp/Xvfb.out"
case "$1" in
start)
echo -n "Starting : X Virtual Frame Buffer "
$PROG $PROG_OPTIONS>>$PROG_OUTPUT 2>&1 &
disown -ar
;;
stop)
echo -n "Shutting down : X Virtual Frame Buffer"
killproc $PROG
RETVAL=$?
[ $RETVAL -eq 0 ] && /bin/rm -f /var/lock/subsys/Xvfb/var/run/Xvfb.pid
echo
;;
restart|reload)
$0 stop
$0 start
RETVAL=$?
;;
status)
status Xvfb
RETVAL=$?
;;
*)
echo $"Usage: $0 (start|stop|restart|reload|status)"
exit 1
esac
exit $RETVAL