geojson

Watching COVID-19 Data for Your County with PostgreSQL and Node

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I have addressed the topic of triggered notifications a couple of times on this blog previously. I’ve taken the opportunity to apply the technique to a current use case – the ability to get notifications whenever the confirmed count of COVID-19 cases changes in my county or surrounding ones.

I am basing this workflow on the Johns Hopkins University county-level data available as an ArcGIS feature service here: https://services1.arcgis.com/0MSEUqKaxRlEPj5g/arcgis/rest/services/ncov_cases_US/FeatureServer

Using the “f=geojson” parameter, it is possible to download the data in a format (GeoJSON) that is readily consumable by OGR. As a result, I was able to initiate a core workflow using the following steps.

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f=geojson, Part 2

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In which I say nice things about Esri. You have been warned…

A couple of weeks ago, I gave a talk at a local Esri GeoDev Meetup (which also served as a convenient way to tell a room full of developers that my company is hiring developers) on a GeoJSON server object extension for ArcGIS Server that I open-sourced some time ago. I started that effort a little while after giving another talk in which I called on Esri to start supporting GeoJSON. I’m not one to wait around so I built an approach myself.

At the most recent meetup, the Esri staff who were there updated the group on upcoming efforts with regard to GeoJSON. Honestly, I’ve known for some time that there are a lot of people inside Esri who “get it” and that various things have been percolating with regard to GeoJSON.

So I was happy to see the official announcement of support for GeoJSON in ArcGIS Online (AGOL) feature services. Included in the support is access through the REST API using an “f=geojson” parameter. This makes it much easier to consume AGOL services in the web client of your choice. (The announcement shows a Leaflet example.)

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Building a Simple Geodata Service With Node, PostGIS, and Amazon RDS

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tl;dr

This post describes the construction of a simple, lightweight geospatial data service using Node.JS, PostGIS and Amazon RDS. It is somewhat lengthy and includes a number of code snippets. The post is primarily targeted at users who may be interested in alternative strategies for publishing geospatial data but may not be familiar with the tools discussed here. This effort is ongoing and follow-up posts can be expected.

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GeoJSON on GitHub: Now What?

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So GitHub announced that you can now automatically view any GeoJSON files that may be in a repository inside an interactive map driven by MapBox technology. This simple enhancement to GitHub is probably one of the most significant developments in the geospatial industry in years. I’ll explain a little later in this post. It’s also important to view this new capability as a great, but limited, first step. I’ll discuss that a little later as well.

While it’s cool to click on a link and just see a map, it doesn’t take long to wonder about how you can use this capability beyond viewing data in GitHub. What follows are three ways to capitalize on GeoJSON in GitHub. Not all are directly related to the new mapping capability, and two have been possible for a long time. That said, the GitHub announcement may draw interest from users who have not previously considered either GitHub or GeoJSON, so I hope these approaches will be useful.

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GeoJSON From ArcGIS Server

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A while back, I posted about my desire to see GeoJSON supported as an output format from ArcGIS Server. I found myself needing that capability so I recently completed, and posted to GitHub, a first cut at a server object extension (SOE) for ArcGIS Server 10.1 that enables output of GeoJSON via an HTTP GET.

Using the SOE is fairly straightforward. If you download the code and build it (ensuring you have installed the ArcObjects SDK for .Net), you can simply move the project outputs to your target machine and use the ArcGIS Server manager to install the SOE. Once you log into the manager application, click “Site” at the top of the page and then “Extensions” on the left. Click “Add Extension” and browse to the .soe file. You should end up seeing something like this:

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OGC Abandons the Web

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Those are my words, not theirs.

It came to light today that OGC has decided to withdraw the GeoServices REST Specification, also known as the “ESRI REST API,” as a proposed standard. I will not take up the relative merits of the specification or the implications of OGC potentially adopting an industry-developed specification that has so much implied workflow embedded in it. With this decision, three facts remain unaltered:

  1. The ESRI REST API will continue forward as a widely-used de facto standard in the form of ArcGIS Server installs and other emulations, such as that in Arc2Earth.
  2. GeoJSON will continue forward as a widely-used de facto standard in the form of numerous open-source implementations.
  3. OGC still has no JSON syntax.

Yes, twelve years after the birth of JSON, five years after the release of the ESRI REST API and its embedded JSON syntax, and five years after the release of GeoJSON 1.0, OGC is still has no entry in the JSON space. Between Esri and GeoJSON, the utility of JSON in web mapping applications has been roundly proven. In the ESRI arena, find me anyone who willingly uses the SOAP API these days while the adoption of support for GeoJSON across the open-source GIS world speaks volumes. The industry has voted with its feet and its code as to what it prefers.

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Checking Out the GDAL/OGR Plugin for ArcGIS

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A while back, I blogged the availability of a GDAL/OGR plug-in for ArcGIS desktop by Ragi Burhum at AmigoCloud. At the time, I was hoping to dig into it fairly quickly but that didn’t happen and I’m finally getting to it. Anyone who has followed this blog for a while knows that I have had more than a passing interest in integrating new data sources with ArcGIS over the years. This comes from the fact that, as a technology geek, I am fascinated by all forms of technology and enjoy the process of integration and, as a consultant providing services to the Federal Government, most of my customers have standardized on Esri tools. Integrations such as GeoRSS, PostGIS, GeoCommons and GeoJSON have directly benefitted my customers for real-world applications so I continue look for ways to remove the barriers between them and the data they seek.

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Put Planet Geospatial to Work for You

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I’m happy to see that James has decided keep Planet Geospatial going. It’s been one of the more consistently valuable resources in the community since its inception and it’s good that it will continue.

While I’m looking forward to seeing how James evolves Planet Geospatial, there are ways to more efficiently extract value out of its current state right now. At its core, Planet Geospatial is an RSS feed. RSS can safely be called “venerable” nowadays, but it still does what it does very well.

Two of my favorite tools for culling down the firehose that is Planet Geospatial are IFTTT (the title of this post is a riff on the IFTTT motto) and Evernote. If you’re not familiar with IFTTT, you should be. It reminds me of a more-intuitive Yahoo Pipes and it allows you to mix channels, triggers, and actions to automate processes of your choosing. It’s become by preferred method of synchronizing my blog with social media and for filtering data sources. It also drives the Unofficial QGIS Info Twitter account.

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