North River Geographic Systems Inc
Spatial Problem Solving
FOSS4G-NA popped up on my radar this week.
So from just the website and a few twitter noise makers it looks like It’s headed to Mission Beach California (San Diego) April 16-18 2019. I’ve made the last 3 – so It looks like I’m going to do my best to make this one. Road Trip? I encourage you to attend and support the FOSS4G North America Community.
I went through a year or so of not talking at conferences. For local ones I’d show up and do something. I taught a workshop at FOSS4GNA 2018. I did a workshop at FOSS4G 2017 in Boston (and it sorta sucked). I need to get out of that mode and talk more – but I’m happier being quiet these days and working with clients.
Anyway – at FOSS4GNA 2018 I discovered something – the OSGEO Suite had disappeared from Boundless’s Website and was replaced with a github repository. It wasn’t long after Don Meltz put up an excellent explanation of the OSGEO Suite. The OSGEO Suite being gone isn’t a problem. It does increase the amount of talking I have to do spend explaining it’s not a problem. I could even compile the suite – but my clients can’t. They are smart people – but the time to compile the boundless suite won’t be happening.
One of the things I keep running into is the idea of an Open Source Server. The OSGEO Suite was well known and I get people asking “Hey – can you set us up a geo server”. They mean the opengeo suite. I then launch into an explanation of what makes up a “geo server” and they go a bit blank and answer me “Yeah – one of those”.
So for the next bit I’m gonna be doing something like this:
I want to explain how this works to people. We’ve gotten a bit deaf by hearing “ArcServer” at every conference in TN as this one monolithic thing you have to install to make a web map…which really don’t need since AGOL appeared but…you want SDE and it’s not called that and you have two people editing but you need SQl Server but you don’t….
Anyway, QGIS/PostgreSQL/PostGIS I’ve installed multiple times and as of late I’m experimenting with geoserver and what it can/can’t do. I have no grand delusions of creating ‘Randy’s Open Geo Spatial Super Duper Server’. I want to get to the point where maybe mapserver is an option in this. So much to learn…so little time.
I suck at github – but I’ve been more active as I try to develop a skill set and get over the angst of pushing and pulling things. I’ve built a vagrant box to install PostGIS/PostgreSQL/Geoserver so I can have something to point at plus it gives me a starting point for an upcoming class I’m in the middle of building. The vagrant box isn’t pretty – I expect to change it over the next bit as it’s mostly pieced together from a lot of other people’s work (Coleman McCormick, Dave Smith, etc). It works though and I have everything but pgadmin 4 running in one spot. Which – I don’t think this is anywhere near “install this for a server” because this is mostly just for talking, training, and testing.
So why vagrant? Why not docker? I can gloss over vagrant faster at theses talks than I can docker. I have 16 minutes to draw diagrams and about 4 minutes to publish one piece of data: QGIS -> PostGIS -> Geoserver -> Leaflet.
Anyway – if you’re up for the possibility of a train wreck of a presentation come by the East Tennessee Meeting in Kingsport next week as I try to explain how this works and hopefully you get excited enough to install some or all of these components and do something cool with your data.
In between work I get a chance to play around with software. I’ve been digging around postgis more and more these days trying to get a better understanding of what it will do or won’t do. It’s a never ending learning experience for me. Sometimes it pays off – the never ending tutorial left me suggesting we dump a database to a geopackage.
I’m great at using geopackage in sentences like “USE GEOPACKAGE” and “Hey – what do you think about geopackage?”. Since I’m actually officially using it I decided to do some digging. It’s a SQLite container. Since it’s a SQLite container I should be able to do some things with it – like…..
I can use the spatialite gui and throw SQL against it and change the tables.
While talking to another person the question started with ‘Well – why can’t we just do the data collection in geopackage?’. Which we did some back and forth and in some cases this would be acceptable vs doing a full postgis install.
So my first question is: Can I make a trigger in a geopackage? The answer is yes. For those of you who don’t know what a trigger does – it responds to some action in a database. In postgresql, I put multiple triggers in a database for a client. Some triggers calculate lengths and some areas and some make a note of who edited a feature.
After some digging I found the syntax and wrote a trigger for SQLite/Geopackage in the form of:
CREATE TRIGGER update_esn AFTER INSERT
ON addresses
BEGIN
update addresspoints set “esn” = (select esn from polygon where st_within(new.geom, geom));
END;
I used the spatialte gui to add the trigger. So if I pass this off to a client they can edit an address and have it automatically pull in the emergency service number. Magic? Eh – close enough for me.
While it’s not going to work for a multi-user situation (or will it – I’ve not investigated) – it works. So now I’m adding widgets to QGIS to aid in data collection.
It’s on.
Website: https://wiki.osgeo.org/wiki/20180813-knoxville-foss4g
Date: August 13th 2018
Location:
Plant Biotech Building
UT Ag Campus
2505 EJ Chapman Dr
Knoxville, TN 37996
I guess it might be safe to call this the Second Annual FOSS4G meeting in TN. We’re headed back to Knoxville on August 13th 2018 for another day of Free and Open Source excitement for GIS. Last year we had about 50 people turn up to hear talks ranging from OSM to LIDAR to Image Classification.
We’re also looking for Sponsors. Right now we have 3 and some money has already been promised. Most likely this even will cost $10 this year to offload some of the headache I got to experience last year as “Money Juggler”. Depending on sponsors this $10 may drop. Registration will be open soon – that’s on my list for next week once I get a few more things settled.
Good people – if you are in the area turn up and come to this. It’s a good time. Good Discussion. Come see how you can benefit from FOSS4G in your world.
So I’ll talk about this finally. I usually don’t talk about “work” unless it’s in generalities about software and processes. I probably should talk about work more.
I’ve never been in a hurricane. I think so far I’ve been in about a handful of earthquakes, stood on one volcano, and I think I’ve seen one tornado. Not that I’m looking to be in a natural disaster – I just don’t have a frame of reference for what happens during a hurricane or a tornado.
If you flash back to early September 2017 the Caribbean was gearing up for a hurricane and. Turns out two hit close together. I had the chance to work in the US Virgin Islands on an addressing project with AppGeo and Spatial Focus several years ago. It’s been a “wait and see” type of deal. We did a little and watch as red tape and things slow it down. I called a few friends down there before the hurricanes hit and wished them well. Overall – there wasn’t a ton of fear but a lot of concern. I was concerned because the 911 system isn’t great as the addressing isn’t wonderful in the USVI.
My memory is getting fuzzy – but it seems like both hurricanes hit and it was a while before anyone could call/email me. Maybe it was late September or October before the phone rang. They needed help to figure out where the tarps needed to go. FEMA/USACE was headed down to bring tarps and supplies – maybe they were already there. A sneaker net of GIS data had cranked itself up on the island as thumb drives were passed around. I started trying to figure out “what made sense with the base data I had available”. I started digging into what USACE and What FEMA would do if your roof was damaged. More or less if you had 50% of the structure of the roof left they could put a tarp on it. I came up with a plan and contacted AppGeo and they tossed a person my way.
Structures were categorized:
NOAA flew imagery of the area. The imagery was a bit rough around the edges but it worked. Actually – let me back up – for what it was it was awesome. Granted it didn’t lend itself to any sort of automatic classification as there was a lot of building lean and some missing imagery. It worked though. That was a great free resource by NOAA.
Hey that’s a lot of points. Yes – 48380 points covering three islands. Granted I didn’t get every house as I had nothing much to start out with except OSM and some USDA NAIP imagery. I would guess I’m within 10% of an accurate building count. Some people have offices/live in shipping containers down there. WHICH – when I was there made me go “awesome” but when looking at the imagery at a shipping container blowing a half mile across a field – not so awesome.
It did give me flash backs to my old remote sensing days with the government. Although this was less refined – it was a game in the afternoons to see how many points I could collect in an hour. Some neighborhoods were easy. Some not so much as there wasn’t much left. The other nice thing that happened was sometime around December I switched over to QGIS 3.0 and started seeing what I could/couldn’t do with this almost released software. Several bug reports were filed so more good came out of this.
The data started making it’s way out to one agency after another. My big fear then was “what if someone uses this beyond ‘roofs'”. I wasn’t doing a full blow damage assessment because I was seeing some evidence that maybe the roof survived but the bottom floors didn’t. Plus I wasn’t on location.
It took me a bit longer to finish than I wanted – Volunteer projects tend to be the last thing I work on most days.
I did start pulling numbers out of some of the work – this is for St John Island:
| Count | Classification | Percent |
| 1487 | 1 – 25% Roof Damage | 41.42 |
| 326 | 26 to 50% Roof Damage | 9.08 |
| 131 | 51 to 75% Roof Damage | 3.65 |
| 126 | 76 to 100% Roof Damage | 3.51 |
| 1007 | No Damage | 28.05 |
| 17 | No Imagery | 0.47 |
| 496 | Structure Destroyed | 13.82 |
| 3590 | Total | 100 |
So 25% of the houses had no roof damage. 60% had something happen. More or less 15% were leveled. I’ve heard ancillary stories where almost all houses had water coming in them and in a warm tropical climate you get mold. Mold would make the house unusable for me.
Anyway – I worry about the 2018 Hurricane season that is upon us. Maybe it will be quiet – maybe it won’t be. AppGeo has Mapgeo for the islands. It worked out well. I’m going to try to “build” a database here so in case something happens and I’m not starting from scratch in case I get to help out again. I hope I don’t help as nothing happens.