It’s been 3 weeks since I set up my little GeoServer experiment and started populating it with various datasets. I thought I’d outline the things I’ve been working on, and what I plan on looking at next. I couldn’t have come as far as I have without the generous help of some of my Twitter friends. I’ve noted below each section those who’ve helped me out. I apologize if I’ve overlooked anyone.
Workspace > Store > Layer
My initial step in getting a useful map up and running was to load some vector data. The first thing I’m sure every GeoServer noob learns is, importing data into GeoServer is a three-step process. The first thing I did was set up a Workspace, which is essentially a folder in my “C:Users<username>.opengeodata_dirdata<foldername>” directory. Then I told GeoServer where to look for this folder. Second step was to set up a Store. A Store can hold a single layer, or multiple layers depending on how you import the data. Why a Workspace AND a Store? I have no idea, but that’s what you have to do, so that’s what I did. Third step was to add a layer or layers to the Store. After that, you can add those layers to a GeoExplorer map, and publish it or embed it in a webpage.
EPSG
Somewhere along the way, GeoServer will ask for a spatial reference system (SRS) for the data you’re adding in the form “EPSG:XXXX”. I figured out very quickly that looking up the EPSG for a shapefile using the built-in GeoServer tool is a PITA. A couple of tools were pointed out to me:
Prj2EPSG (http”//prj2epsg.org/search) and Spatial Reference (http://spatialreference.org)
Although the data I use comes to me in many different projections, I use a limited number of spatial references in my output. I now keep a Post-It note on my desk with the 5 EPSG codes I use most often.
(Thank you @mcbride_bryan, @spara)
Styling
Symbolizing vector layers in GeoServer is a little cumbersome, but I was able to figure it out. and it’s not too much of a chore for simple layers. Options are limited, and I’ve been pointed to a few other tools when it comes to styling layers. uDig, Atlas Styler, and Arc2Earth all look promising and I’ll be checking them out in the near future.
(Thank you @mcbride_bryan, @spara)
Rasters
One of my more frustrating episodes was an attempt to get raster data to display in my GeoExplorer map. The GeoServer GUI and documentation led me to believe I could just load an ArcGrid (binary) dataset into GeoServer. I wasn’t able to get that to work, and have been told by some that it’s not supported. Next, I tried a jpeg. I assumed by including a world file (jgw) everything would be hunky-dory. I assumed wrong. It was pointed out to me that a projection file (prj) needs to be included, too. That got the raster to display, but brought my poor little server to its knees. Finally, I settled on a GeoTiff. By using jpeg compression within the GeoTiff, I was able to keep the file size reasonable, and GeoServer handled it just fine.
(Thank you @geowolf, @storm72)
Zoom Levels
For the life of me I could not figure out how to zoom in close enough to make my newly loaded raster data useful. I know I had seen many GeoServer/GeoExplorer maps able the zoom in nice and close, but it just wasn’t happening for me. Finally, it was pointed out that changing the default base layer to something other than Google Terrain fixes that problem. Worked like a charm. Why would the Google Terrain base map limit zooming in close? I have no idea. Just one of those things.
(Thank you @manicmapper)
HTML and CSS
After getting these things working, I decided to dress up the web page that holds my GeoExplorer map a little bit. I have Dreamweaver CS4, and I use that to manage a couple of websites, but it’s really much more than I need, especially for a little single page website. I looked around and found Aptana Studio. After using it for an hour or so, I’ve come to really like it. It color codes and formats the HTML and CSS so it’s readable, and I think the preview feature works better than what Dreamweaver has. I might also give Komodo Edit a try, and see how that compares.
(Thank you @mcbride_bryan)
What’s Next?
Probably some more experimenting with the various SLD editors, brushing up on my HTML and CSS skills, and diving into JavaScript, which I’m embarrassed to say, I haven’t really looked at in over 5 years.
What’s it look like?
Here it is as of January 31, 2011:
And a link to the site so you can see it now:
Don’s GeoSandbox
Thanks for the shout-out Don. I’m glad the tip on the zoom levels helped you.
Like you, I was unsure about the role of workspaces vs stores. What we’ve found useful is to use the workspaces to group together data from a particular source. And then the store is a specific dataset from that source.
For example, a major data supplier for our municipal clients is the Victorian Department of Sustainability and Environment. So each municipality’s GeoServer has a workspace called DSE. Then for each of the Vicmap datasets that DSE supply, we allocate a store – one for Vicmap Transport, one for Vicmap Property, etc. And then within each of the stores are the individual layers.
So far, this is proving to be an effective way to organise the data.
All the best with your continuing experimentation.