GeoServer Blog
GeoServer Roadmap updated
So this may be about as close as I’m going to get to ‘Developers notes’ for awhile (though I may let myself work on some GeoJSON or GeoRSS output over the holidays), but wanted to let everyone know that I updated the GeoServer Roadmap in an attempt to capture the latest directions of the community. If I’ve missed anything please don’t hesitate to update it (all our docs are wikis). The roadmap had fallen out of date - the ‘short term’ projects were set to complete in september - so I’ll try to be more vigilant about updating it more regularly.
But I must say it was quite satisfying doing the update, as the GeoServer community had actually managed to hit most of the things we said we would. The demo site is up, GeoCollaborator stuff has moved from discussions to the beginning of an implementation. 1.4.0 is out, and the WCS branch not only got up a release, but is a part of the GeoServer main line as 1.5.0-beta1. We’ve also had some work on tiling/caching with a tutorial on running OSCache. The only thing we didn’t get to was an improved SLD editor, but I’m hoping we can do it after our web gui overhaul - which made it’s way up to ‘medium term’, as we’ve been feeling the pain too long. If people have suggestions of a good web framework let us know, the ones we’re likely going to look at are Wicket, WebWork2, and Google Web Toolkit.
Elsewhere on the horizon we’ve got WFS 1.1 (which includes GML 3.1.1 simple features) from OWS-4 coming home, and Justin’s made some nice improvements on that branch. And 3d and 4d support in WCS will be in the works as the 2D version works towards the stability of 1.5.0. Also Social Change Online and Axios are likely going to be doing some more work on bring the new Feature Model home, which should be a huge step forward. On the non-technical side of things we’re also going to be working on changing the license of the ‘core’ of GeoServer (configuration of data and access to GeoTools) to LGPL, which should enable others to build even more interesting services on top.
So stay tuned, there’s lots of fun coming from the edges to the mainstream of GeoServer, and there are some other fun things that may be in the works. It’s going to be an exciting year for sure.
Happy Holidays from all of us working on GeoServer!
GeoServer 1.4.0 has arrived!
It’s finally here! Version 1.4.0 is out the door and kicking. This is quite an exciting release for us because it is taking GeoServer in a new, more developer friendly, direction with the Spring framework it is built on. What we gain from this new framework is the ability to modularize GeoServer into separate components and allow for outside developers to create plug-ins easily. It used to be a lot more difficult to add extensions, comparatively to what we have now, and this means that we can look forward to new and interesting additions from the many users out there.
That said, I will point you at the documentation that describes just how to write your own plug-in: http://docs.codehaus.org/display/GEOSDOC/4+Programmers+Guide
Of course there are many bug fixes and improvements in this release. We have also worked on stability a fair amount and are currently testing version 1.4.0 on our demo server: Sigma . So if you have a WMS up and running, feel free to point it at our layers and use our data. The more we can hit the server the easier it will be to find problems.
Hot on the heels of this release is GeoServer 1.5 with Web Coverage Service support. We hope to see the first release candidate in January. So stay tuned!
You can grab the 1.4.0 release here.
Client applications
These are some of our favorite client applications. There are some others out there and you can refer to the GeoServer client page for more information.
MapBuilder A javascript client that supports OGC WMS and WFS requests, so you can view and edit spatial data through the web browser. GeoServer has MapBuilder built in as its map preview tool.
Open Layers OpenLayers is a javascript tiling web-based client just like Google maps. It supports OGC WMS requests.
MapBender Mapbender is the software and portal site for geodata management of OGC OWS architectures. The software provides web technology for managing spatial data services implemented in PHP, JavaScript and XML. It provides a data model and interfaces for displaying, navigating and querying OGC compliant map services. The Mapbender framework furthermore provides authentication and authorization services, OWS proxy functionality, management interfaces for user, group and service administration in WebGIS projects.
Udig Udig is a desktop client that supports OGC WMS and WFS requests. It is built off of the same library as GeoServer: GeoTools.
GVSig GVSig is a desktop client that supports OGC WMS and WFS requests, similar to Udig.
Google Earth GeoServer can serve up data as KML/KMZ that can then be loaded in Google Earth. There is a tutorial here that you can read to start viewing your in this client.
NASA World Wind World Wind supports WMS requests so you can serve up your data with GeoServer to it. Read this tutorial for how to do this.
The WFS and WMS Services
OGC Web Services for accessing Geographic Data
The Open Geospatial Consortium has defined several Open Web Services for accessing (usually geographic) data. There are two basic service sets - the Web Feature Services (WFS) and the Web Map Services (WMS). The WFS is concerned with direct access to your data - reading, writing, and updating your features. The WMS is concerned with transforming your data into a map (image).
![](http://udig.refractions.net/confluence/images/icons/emoticons/information.gif) | **What is a Feature?** A feature is an Object that is an abstraction of a real world phenomenon. This object has a set of properties associated with each having a name, a type, and a value. An example of a feature might be Road with a Name, Location (line geometry), Width, Speed Limit, and Jurisdiction. Typically these features are stored in a [spatial database](http://udig.refractions.net/confluence/pages/viewpage.action?pageId=5223), shapefile, or other format. |
![](http://udig.refractions.net/confluence/images/icons/emoticons/check.gif) | **OGC Open Web Services** The OGC Web Services provide access to the features - either directly or as images (maps) - in a standardized way independent of the company who created the server or the actual format the data is stored in. |
What to use a the WFS services for
A WFS allows uniform direct access to the features stored on a server. Use a WFS when they want to perform actions such as:
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query a dataset and retrieve the features
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find the feature definition (feature’s property names and types)
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add features to dataset
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delete feature from a dataset
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update feature in a dataset
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lock features to prevent modification
A WMS allows for uniform rendering access to features stored on a server. Use a WMS when you want to perform actions such as:
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Producing Maps
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Very simple Querying of data
Why use open standards?
Why use Open Services
GeoServer is strongly committed to open standards for its geospatial web services. Currently this is strongly centered around the Open Geospatial Consortium’s Open Web Services architecture, as they have the largest consensus among industry and government, and have some very high quality specifications. But GeoServer remains un-ideological about the particular standard, as long as it is fully open and widely supported.
This insistence on open standards is practical, if immense amounts of geospatial information are to be truly accessible it will only be possible through widely used open standards. The GIS industry has always had a myriad of formats, making the combination of data from different sources an exercise in frustration, spending massive amounts of time and money with data conversion, or simply scrapping the conversion and duplicating the work of gathering the data. The Internet and Web Services open up new possibilities for quickly obtaining geographic data, but unless open standards are utilized users will have to decide which geospatial web they want to access, obtaining the appropriate client software for each. Imagine if Netscape and Internet explorer had different Internets - if the browser wars had extended to servers, instead of having an open source standard with Apache - then users today would have to decide which Internet they wanted to get their information from, depending on which browser they were using.
Relying on a non-open standard for exchanging geographic information ensures that it can only be exchanged with others who have bought the same system. The cost to entry to that geospatial web is whatever the server vendor chooses to charge, and the only geographic information available will be by ones who could afford the cost, or who are in the good graces of the company providing the software. An open standard enables competition in an open marketplace for providing geospatial servers. There is no lock-in to the initial choice, as it is easy to switch one vendor’s implementation for another, or even to migrate to an open source solution (and back if the oss solution did not fully meet the needs). Without an open standard such migrations would involve a replacing the whole system, not just the component needing improvement.
Several mainstream technology corporations are jumping into the geospatial game, giving away access to their geographic information, allowing users to add additional information. But without open standards and a variety of implementations users will have to pick which proprietary geospatial web to join, instead of creating an open Geospatial Web where all information about a place is searchable and available.
It is getting easier and easier to roll a mapping application, directly connecting a PostGIS or MySQL database to a simple web mapping front end. Putting standards between the display of the map (WMS), getting the raw data (WFS) or the updating of information (WFS-T) can seem like an extra hassle for implementors. But doing so allows anyone to access the same information that is displayed, and overlay and combine it with other geographic information, providing more context and the potential of generating new information from analysis. With a self built system there is generally only one way to display the information, the one provided. If an open standard is used then it can be used in a desktop GIS, web applications, 3d viewers, or specially built geographic visualization.
(we should have a picture of a client here getting data from a bunch of different WMSes and even a WFS, as a concrete visualization of what is possible with standards - even a before/after picture, of just putting one’s data up on the web, and then one’s data overlaid on lots and lots of context from diverse sources)
Tutorials
- Using Binary Comparison Operators in GeoServer Filters
- Utilizing the Demo Section in Geoserver
- How to Implement Basic Security in Geoserver
- How to create Tile Layers with GeoServer
- How to style layers using GeoServer and QGIS
- How to Publish a GeoTIFF file in GeoServer
- A Comprehensive Guide to Publishing a Shapefile in GeoServer
- GeoServer About & Status - A Practical Guide
- GeoServer installation methods on Windows
- Introducing GeoSpatial Techno with a Video Tutorial