Last week in Santa Barbara, during the ESIP Federation summer meeting, the NASA SPG hosted a Web Services technical session. I somehow got the job of lining up speakers and moderating the session, always a bit of a nail-biter. The session went well and we had some great speakers.

The presentations can be found on the SPG web site.

First up, I tried to set the stage a little bit, based on where I thought the audience was in terms of knowing about web services and REST. My biases probably showed through, but I really do think that anyone building web services that are meant to be generally accessible should not be using straight “SOA” (i.e. SOAP, WS-*, etc.) with no regard to REST. Furthermore, I think that REST wrappers around RPC-style interfaces is stopping short of where things could be.

Next, Josh Lieberman gave a presentation about OGC’s current mindset vis a vis REST. It looks to me like there is some critical thinking going on inside OGC on this topic. It remains to be seen whether there is also going to be any real motion towards specs that use REST the way it could be used. Look at some of Sean Gillies postings about APP for how OGC could benefit from REST. (Sean was, unfortunately just arriving in France and unavailable to come to UCSB).

Michael Burnett talked about ECHO. ECHO is a full-bore SOA implementation of a metadata clearinghouse for granule level NASA data. ECHO is actually testing out the REST waters a bit with some early experiments. Given when ECHO was initially designed, and the need to continue long-term, stable operation, I don’t think I can fault them for where they are today. There’s a lot to be said for keeping a stable API that can itself be wrapped in newer skins.

Switching gears a little, Jason Symonds from NOAA showed us how he’s been building a drought portal. His portal acts as a web services client to pull information from many other web sites into a single set of web pages. Along the way he’s had to develop a few web services of his own which he’s also making available via the portal.

Tyler Stevens demoed a new service offered by GCMD (his presentation is here, the portal itself is here), namely a web services discovery portal. GCMD has been a mainstay for dataset discovery for a number of years. More recently, they have been accepting submissions of web service descriptions that now can be found in the portal. What I really liked here is the way the services themselves can provide information about how to use them. For instance if you click on the WMS service link for this DataFed service entry, it brings you to a forms builder that helps you build WMS URLs.

Karl Benedict’s talk about the New Mexico Geographic Information System showed how they are developing a RESTful set of services to allow data upload and subsequent automatic generation of WxS services on that data. As the system has become easier to use, the amount of data being made available has been increasing by leaps and bounds.

The last talk came from the astronomy community, who seem to be a bit out in front of the earth observation community when it comes to a concerted effort to move to REST principles. Matthew Graham gave a great overview of what is going on in Virtual Observatories. I’m always a little surprised when I see how other communities really are not all that different from the ones I’ve been working in for years. When you get right down to it, I guess everyone has data ingestion, integration, storage, and service delivery problems, so I should not be surprised. The VO community seems to be tackling the problem with gusto and has been making good progress, from the look of it.

At the end, we had a discussion about the questions raised in the initial session description and also touched briefly on how NASA could work to maximize its benefit from being an OGC member (broadly speaking, not restricted to web services). Two whiteboard pictures (one, two) emerged, and there will be summary information posted soon, I think.

[Update: Summary meeting notes were just posted on the site. -- July 16]

Has anyone ever run a service discovery and orchestration scenario like the one on page 7 of this document in any setting other than a demo? How far away from being able to do this in “real life” are we?

Today I found myself sitting in a classroom discussion when the need arose to figure out how far each of 344 survey respondents had come to the place where the survey was being conducted. The survey included the home zip code of the subjects, and we knew, of course, the zip code of the survey location.

While I was Googling for how to best geocode the zip codes, I happened to also ask in the #geo irc channel (on oftc.net) whether there were any free distance calculation web services. Rich Gibson, who constructed geocoder.us piped up and said he was adding to the API for its web services and did people have any requests. What luck! I asked for something that given two zip codes would return a distance.

Not long thereafter, here’s what he came up with:

  http://geocoder.us/service/distance?zip1=41080&zip2=02139

which would return the distance between Petersburg, KY and Cambridge, MA.

So I was off to the races! I copied the list of zip codes from the Excel spreadsheet and pasted them into an Emacs buffer, then saved them as ‘zips’. Then in the shell (I use tcsh…):

First to get rid of duplicates:

% sort zips | uniq > zips2

Then, loop through them. I put line breaks with continuation characters into the geocoder line to fit inside this blog post.

% foreach zip ( `cat zips2` )
foreach? echo ${zip} `curl \
"http://geocoder.us/service/distance?zip1=41080&zip2=${zip}" \
 | sed -e 's/.*=//' | sed -e 's/ miles$//'` >> distances
foreach? end

And that’s it! I pasted the results back into the spreadsheet, got rid of the three bogus zipcodes in the data that resulted in errors from geocoder.us, used VLOOKUP to pull out the distances and I was done.

The service returned errors three times. I used the USPO zip code reverse lookup to verify that the codes were indeed bogus.

That’s my kind of web service. No WSDL, WADL, or WS-anything.

(Yes, I could have used Perl, Python, Ruby, etc. but I learned shell commands in 1981 before we had all that fancy stuff and it’s the first thing I try.)

One thing I didn’t buy yesterday was a MacBook Air. I went to the Chestnut Hill Mall Apple store to see what it looked like but they didn’t have any to show. The store won’t have any to look at for two more weeks.

Instead I ordered a MacBook from the Apple Education for MIT site (they are about $100 less there, and there’s a savings on AppleCare). When it gets here in a few days, I’ll clone my MacBook Pro’s hard drive to the MacBook and send the MBP to my son. They only thing I’ll miss, I suspect is the lighted keyboard, something I’ve come to like a lot. I ordered the 250GB drive and I’ll shop around for a RAM upgrade.

Then, with the savings, I’m thinking pretty seriously about an iPhone, something that would be fun to play with for the Museum Without Walls.

The iPhones I looked at at the Apple store had the new location detection firmware. The store is here but the phone indicated it was a good 1000′ southeast of the store, south of what’s labeled Holyhood Cemetery. That’s not exactly pinpoint accuracy. But the Skyhook wifi database may not have included the mall, and thus the iPhone was probably using the Google cell-tower locations to find itself. Skyhook claims 10-20m accuracy in urban areas. That sounds pretty reasonable to me.

So I’m going to blame my recent lack of postings on my blog to the fact that, like Hobu, I was finding that a Plone-based blog was not so easy to deal with. I decided to jump into the blogging mainstream with WordPress, so here we go.

Along with the switch to WordPress, I’m going to expand from mostly geo-related topics to things I’m dealing with at MIT as well. So for those of you who want exclusively geo-news, link to the geo category and the geo feed in Atom, RSS, or RSS2.

I still have to switch over the Feedburner feeds and tweak a few more bits and pieces, but overall the new version is ready to go.

As I mention in the About page, I’ve kept the old blog intact so that all the permalinks still work.