mapcache

000-default.conf

LoadModule mapcache_module   /usr/lib/apache2/modules/mod_mapcache.so
<VirtualHost *:80>
        # The ServerName directive sets the request scheme, hostname and port that
        # the server uses to identify itself. This is used when creating
        # redirection URLs. In the context of virtual hosts, the ServerName
        # specifies what hostname must appear in the request's Host: header to
        # match this virtual host. For the default virtual host (this file) this
        # value is not decisive as it is used as a last resort host regardless.
        # However, you must set it for any further virtual host explicitly.
        #ServerName www.example.com

        ServerAdmin webmaster@localhost
        DocumentRoot /var/www/html

        # Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
        # error, crit, alert, emerg.
        # It is also possible to configure the loglevel for particular
        # modules, e.g.
        #LogLevel info ssl:warn

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined
        LogLevel trace8
        # For most configuration files from conf-available/, which are
        # enabled or disabled at a global level, it is possible to
        # include a line for only one particular virtual host. For example the
        # following line enables the CGI configuration for this host only
                # after it has been globally disabled with "a2disconf".
        #Include conf-available/serve-cgi-bin.conf

<IfModule mapcache_module>
   <Directory /data/>
      Require all granted
   </Directory>
   MapCacheAlias /mapcache "/data/mapcache.xml"
</IfModule>
</VirtualHost>

readme.md

####Build

docker build -t mapcache-memcached .

####Run

Run memcached container (not required to reproduce error)

docker run -it -d --name mymemcached  memcached

Run Mapcache linked to Memcached

docker run -it -d -p 8181:80 --link mymemcached:mymemcached --name mapcache-failing  mapcache-memcached

####Enter container and start Apache2 service

docker exec -it mapcache-failing /bin/bash

Inside container do:

service apache2 start

Tail Apache error log and segmentation fault:

tail -f /var/log/apache2/error.log

Go to your browser and test:

http://:8181/mapcache/demo/wms

Dockerfile

# MapCache  container with Memcached support
#This setup reproduces segmentation fault when using memcached in Mapcache as cache backend

FROM ubuntu:14.04
MAINTAINER Martin Bjærge Jensen, martin@septima.dk

# Set correct environment variables.
ENV HOME /root

ENV TERM=xterm
ENV DEBIAN_FRONTEND noninteractive

RUN apt-get update 

# Install MapCache
RUN apt-get install -y \
	apache2 \
    wget \
    nano \
    cmake \
    build-essential

RUN apt-get install -y \
    libpng12-dev \
    libjpeg62-dev \
    libcurl4-gnutls-dev \
    apache2-dev \
    libpixman-1-dev \
    libpcre3-dev

RUN apt-get install -y \
#  libgdal-dev \
#    libgdal1-dev \
#    libgeos-dev \
#    libapr1-dev \
#    libaprutil1-dev \
    libapr-memcache-dev \
    apache2-prefork-dev 


#release 1.4.0 causes segmentation fault
RUN wget https://github.com/mapserver/mapcache/archive/1.4.0.tar.gz -O mapcache-1.4.0.tar.gz


RUN tar xf mapcache-1.4.0.tar.gz
RUN cd mapcache-1.4.0 && \
    mkdir build &&\
    cd build && \
    cmake .. -DWITH_FCGI=0 -DWITH_SQLITE=0 -DWITH_MEMCACHE=1 -DWITH_OGR=0 -DWITH_GEOS=0 -DWITH_RIAK=0 -DWITH_PCRE=0 && \
    make && \
    make install

RUN ldconfig


# Enable site
ADD 000-default.conf /etc/apache2/sites-available/000-default.conf
RUN a2ensite 000-default.conf 


EXPOSE 80
ADD start.sh /start.sh
RUN chmod 0755 /start.sh

# Add VOLUMEs to allow backup of config, logs and databases
VOLUME  ["/data"]

ADD mapcache-default.xml /data/mapcache.xml


USER root
RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*


CMD ["bash", "start.sh"]

# OR :
# service apache2 start

mapcache-default.xml

<mapcache>
   <cache name="disk" type="disk">
      <base>/tmp</base>
      <symlink_blank/>
   </cache>
   <cache name="memcache" type="memcache">
     <server>
            <host>mymemcached</host>
            <port>11211</port>
      </server>
    </cache>

   <source name="vmap0" type="wms">
      <getmap>
         <params>
            <FORMAT>image/png</FORMAT>
            <LAYERS>basic</LAYERS>
         </params>
      </getmap>

      <http>
         <url>http://vmap0.tiles.osgeo.org/wms/vmap0</url>
      </http>
   </source>

   <tileset name="test">
      <source>vmap0</source>
      <cache>memcache</cache>
      <grid>WGS84</grid>
      <grid>GoogleMapsCompatible</grid>
      <format>PNG</format>
      <metatile>5 5</metatile>
      <metabuffer>10</metabuffer>
      <expires>3600</expires>
   </tileset>

   <default_format>JPEG</default_format>

   <service type="wms" enabled="true">
      <full_wms>assemble</full_wms>
      <resample_mode>bilinear</resample_mode>
      <format>JPEG</format>
      <maxsize>4096</maxsize>
   </service>
   <service type="wmts" enabled="true"/>
   <service type="tms" enabled="true"/>
   <service type="kml" enabled="true"/>
   <service type="gmaps" enabled="true"/>
   <service type="ve" enabled="true"/>
   <service type="mapguide" enabled="true"/>
   <service type="demo" enabled="true"/>

   <errors>report</errors>
   <locker type="disk">
     <directory>/tmp</directory>
     <timeout>300</timeout>
    </locker>

</mapcache>

start.sh

#!/bin/bash

# Start apache
#/usr/sbin/apache2 -D FOREGROUND
tail -f /var/log/apache2/error.log