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GeoServer Beginner’s Guide (not only for novice)

Let’w talk about a new book on Geoserver: a useful manual for everyone.Here’s my review:

“Who has had the idea of entitling this book “Beginner’s guide”? This manual is much much more! Actually, besides supplying beginners with the basics of GIS and Geoserver, it can well work as an operational manual at a more specialized level. Since several years I’ve been working with this software (Geoserver) for job, and therefore I have matured a certain experience; in the book I found some information on Geoserver that previously I could obtain only through several researches in websites and thematic forum. I’ve appreciated very much the “practical” sections and the multi-choices quiz that invite the reader to think again to what he has previously read and, possibly, to read it once more.

The section on GIS basics is very important because the given notions help in understanding and fully exploiting the potential of Geoserver; I’ve enjoyed very much to successfully execute on an ubuntu-like system the detailed and precise procedure for installing Geoserver and all necessary software. Chapters 3, 4 and 5 gradually introduce the reader into the secrets of the management interface and to the way of accessing and loading spatial data. Also in this case I’ve tried to execute the described procedures by following the tips of the authors: surprise! I’ve found myself perfectly comfortable both as an “absolute beginner” and as a GIS expert. The descriptions and the observations on the “WMS reflector” functionality are very useful, since this tool helps the user to publish spatial data according to his own needs.

Also in chapter 6 the approach is very “soft”, since it introduces the reader to the basics of the largely applied OGC standard; but then, gradually, the book checks the reader’s abilities with the practical section “time for action”, sums up the notions he has just learned with “What just happened?” and finally brings him to dare with the section “Have a go hero”.

In my opinion, from chapter 7 on, topics switch to an intermediate level: implementation of simple webgis applications, configuration of geowebcache software to enhance performances, description of REST interface to automatize tasks, up to the very important topic of security are treated. Nevertheless, the confidential tone, the numerous references to examples and practical procedures, together with the concepts learned in the previous chapters, allow even the less expert reader to try to implement and manage a simple spatial data infrastructure.

Chapters 11 e 12 are really appreciable: they list and describe the basics (and not only) for tuning Geoserver and enhancing its performances in enterprise environments, and how to manage “troubleshooting” also by means of several active “mailing lists”. I’ve been impressed by finding in about 30 well organized pages all the useful references, which makes this book resemble a real, easy-to-use and complete “practical handbook” To sum up, I think that this book is suitable and complete both for those who approach Geoserver for the first time and for those who work daily with this software.”

That’s all!  Good job!

You can find more informations and buy the book  here

The importance of being dynamic (for a WFS)

These are the results of a “personal” functionality comparison on some GIS desktop:

– web feature service:  Sardinia Region WFS (2000 objects limited)

– layer used: usoSuolo2008

Udig 1.2: AUTOMATIC load of the current map extent objects; AUTOMATIC new request during the navigation (zooming, pan, ecc.); preservation of the thematization; AUTOMATIC load of the web service intire list layer;

gvSIG 1.9: MANUAL load of the current map extent objects; MANUAL new request during the navigation (zooming, pan, ecc.);  NO preservation of the thematization; AUTOMATIC load of the web service intire list layer;

quantum GIS 1.3: NO load of current map extent objects; AUTOMATIC load of the web service intire list layer;

 

ESRI arcGIS 9.3.1: NO load of current map extent objects; NO loading intire list layer of the web service.

 

As you see with these requirements and these Web Feature Service charateristics the best GIS desktop that provide “dynamic WFS request funcionality” is Udig 1.2  followed by gvSIG 1.9, Qgis 1.3 and arcGIS 9.3.1.

Web Map Service

A Web Map Service (WMS) allows to show over the internet geographic contents stored in a spatial database or file system by using a HTTP protocol. Both a web-based application and a desktop GIS application can make a request (in the form of URL) to the map service which answers with georeferenced map images (usually PNG or JPEG). Some WMS manage the transparency and give detailed information of the showed geographic contents.

The prevalent specification for this standard is published by OGC (Open Geospatial Consortium) and referenced in INSPIRE Directive too. gvSIG and QGIS are excellent WMS client, while mapserver and geoserver are good OGC WMS server. The Sardinia Region exposes a WMS for raster images and one for vectors, with a good user guide (at the moment available in Italian only).