Mapserver

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General MapServer notes

MapServer web site

MapServer is for building Web-based GIS applications.

What can I do with MapServer? It can act as a WMS. It can act as a WFS.

What is a WMS? An OGC-compliant "Web Map Server"

What is a WFS? An OGC-compliant "Web Feature Server" allows WFS clients to access feature sets from the WFS instead of entire maps.

You can combine it with other components to enhance its functionality.

Windows / Corvallis implementation

At Public Works, we live in a Windows world here, but why let that slow us down? We started off with ELLAmaps which is based on a MapServer 3. server. Now moving on to something better.

Server software

Options: precompiled binaries: MS4W, FWTools, HoBu

FWTools 0.9.9 - Frank Warmerdam's version built on Python. Testing this one now...
HoBu supports Python, PostGIS, ArcSDE, Oracle
MS4W includes Apache and PHP/MapScript

FWTools

Installation

Download the binary and execute it.

MrSID note Installing support for MrSID plugin requires a version of LizardTech SDK which is not currently available. Oh well.

Configuration

After it's installed you have to enable the CGI portion. I did this by creating a new "Virtual Directory" called fwms, so I can access the mapserv.exe with a URL like this: http://localhost/fwms/mapserv.exe

It gives me the old familiar "No query information to decode. QUERY_STRING not set." error so I know it's executable.

Testing

Now I need to root around and find a MAP file to test it. I built a hello world and a parks map and accompanying template files.

Then I need to build an appropriate URL to test it. How about http://localhost/locn/park.html

Python Mapscript

So how do I access fwtools' Python from mapserver?

Linux / CDS implementation

Installation

The INSTALL file has this text in it: "Visit http://mapserver.gis.umn.edu/ for full documentation and installation instructions." It took me a good 30 minutes to find any useful documentation at the UMN site!

Look in their MapServerWiki. Here is a doc on MapServerCompilation

Server

I built a special Web server to run MapServer for two reasons. First, I generally run MySQL not PostgreSQL due to the requirements of other packages that I use. I might think PostgreSQL is better than MySQL but the other packages don't support it.

Second, the current version of MapServer requires that PHP be run as a CGI instead of as a loadable Apache module. For MapServer this is not a big deal but again some of my other software packages won't work when used with the CGI version of PHP.

I use Trustix Secure Linux 2.1 on the map server. I find it to be easy to maintain and not bloated like recent versions of Redhat. The support from the Trustix team is excellent.

Relevant installed packages with TSL 2.1 include

Apache 2.0.51 -- installed from apache TSL package

PostgreSQL 7.4.5 -- installed from postgresql and postgresql-devel TSL packages

GD 2.0.27 Boutell's graphics library is not available through Trustix. The Redhat version is outdated too -- you need GD version 2. So I built it myself. I had to install the zlib-devel package to get it to compile on TSL.

PHP As mentioned above I have to build PHP 4.3.9 as a CGI -- the TSL version is a module. Building PHP required installing these TSL packages: flex,

The options I used for the PHP configure script are:

./configure \
        --with-pear \
        --with-regex=system \
        --with-zlib \
        --with-gettext \
        --with-xml \
        --with-pgsql

This is a bit minimal for me. Usually I build in a lot more features but then again, normally I load PHP as a SAPI module so it does not matter if it's a bit bulky. To run it as a CGI I want it to load as fast as possible so I leave nifty extra features like internal support for JPEG's and PNG's turned off. Maybe I should turn off XML support too...

Configuring Apache for CGI PHP

I could not find a good clear example of this -- apparently everyone uses SAPI PHP.

ADD APACHE MY CHANGES HERE!!! Projections - PROJ 4.4.8 installed from RPM for Redhat. Proj includes a library for performing respective forward and inverse transformation of cartographic data to or from cartesian data with a wide range of selectable projection functions.

Map file support -- Raster and Vector files

GDAL 1.2.3
GDAL is the "Geospatial Data Abstraction Library". GDAL is a translator library for raster geospatial data formats.

OGR The OGR library is a subcomponent of GDAL so you don't need to worry about it if you install GDAL. The OGR Simple Features Library allows MapServer users to display several types of vector data files in their native formats. For example, MapInfo Mid/Mif and TAB data do not need to be converted to ESRI shapefiles when using OGR support with MapServer.

I built the entire GDAL package with './configure; make; make install'

Building MapServer

MapServer wanted me to install Freetype but there is no TSL Freetype so I installed version 2.1.9 from source with the traditional './configure; make; make install',

The configuration I used for the actual MapServer build looks like this:

./configure \
  --prefix=/usr/local/mapserver \
  --with-httpd=/usr/sbin/httpd  \
  --with-gd=/usr/local  \
  --with-freetype       \
  --with-jpeg           \
  --with-proj           \
  --with-ogr=/usr/local/bin/gdal-config \
  --with-gdal=/usr/local/bin/gdal-config --with-wfs \
  --with-tiff \
  --with-php=../../Languages/php-4.3.9

I would like to add --with-postgis but I have not installed PostGIS yet.