Editing GIS data on the web: When do you need server-side code

Most GIS professional’s initial foray into web-mapping involves building a client side application using a JavaScript API such as Leaflet, OpenLayers, or Google Maps. They learn to set the initial location and scale, place a point or two on the maps, and maybe even load their own GIS data from a GeoJSON file.

This is exciting. A whole new world is opening up. They are now web mappers and it was EASY! And it usually takes only a few more minutes for them to ask How can I edit this data?”. That is the point when their instructor launches into a long string of techno-babble involving client-server architecture, SQL, spatial databases, and server-side coding. And our hypothetical GIS professional’s mood begins to sink. Its not that easy after all. Surely there is a Leaflet plug-in that they can just load in that works like magic?

Unfortunately, there is no plug and play solution unless you are willing and able to pay large amounts of money for commercial hosting. The good news is that if you are willing to put in a little bit of effort to learn the basics of server-side programming with PHP and SQL you can set up a secure web GIS application that allows editing using open source software that does not require any licenses, subscriptions, or per-user fees.  The first step is understanding whether or not you need to have server-side code at all or if you can meet your needs with a client-side only application.

This video is my attempt to help you answer that question. It is the second lecture in a course on server-side web GIS programming with Leaflet and PostGIS. This course will have more than 70 lectures and will be available on Udemy by the end of June 2018. It will explain how to create web GIS applications that access data stored in a PostGIS database and how to allow editing and creation of data in those applications.

This course does have two prerequisites. Display and Analyze GIS data on the web with Leaflet and PHP registration, login, and content management system. Both of these prerequisites are available now for $20($15 until the end of July with the coupon code JULYSALE), so if you decide that you will need a server-side web GIS application, you can get started with the prerequisites now.

One thing I do not mention in the video but will add before the course is released is that data stored in a PostGIS database is inherently more secure than data stored in a GeoJSON file on the server, so that is another reason you might want to use server-side code in your web GIS application.