Mapfile + OpenLayers: accessing the database by column names (hover, onclick functionality) without using MapServer templates?

Question

What I'm trying to accomplish: take the functionality below (see picture) and do the same without using a MapServer template (if this is even possible).

I currently have a mapfile, and an openlayers file. All the data is being displayed correctly.

In my mapfile, I reference a database. I call out that database by a column name so what is what's used for the label on the map. Quite simple.

Now, the thing here is that I'm accessing just a standard php/html file. Not a mapserver template, like:

http://192.168.2.164/cgi-bin/mapserv.exemap=%2Ftmp%2Fnavhome%2Fnavcore%2Ftemplates3%2FAllAirports.map&mode=nquery&imgext=-180.000000+-107.943706+180.000000+107.943706&imgxy=640+384&zoom=0&qlayer=Cities&layers=world&searchmap=true&img.x=705&img.y=347

Example: 123.456.7.890/mymap.php in the browser is what I want. Not the above.

Now if I wanted to accomplish this using a MapServer template (correct me if I'm wrong on my terminology), this has proven to be quite easy, because you can reference

map_body.html
map_header.html
map_footer.html

in your Mapfile. In those files you can do some javascript and whatnot, reference the columns in the DB and it works. See below for an example of this (top left is the onClick functionality when you click on a point on the map, where the mouse is is just the mouseover).

See below: this is what I want to do without the cumbersome MapServer functionality, ie sluggish navigation buttons

So what I'm trying to wrap my head around is: how do you set up the database references in your .html/php file? Or, how do you reference the templates (map_body.html, map_header.html, map_footer.html) from your MapFile in your OpenLayers file?

Answer 1

I am not sure what you are trying to achieve here (the image is not extra clear), but for whatever you are trying to do, you can certainly achieve it without using MapServer template.

If the issue is about clicking on an OpenLayers map and have some information back from a database, there are many ways for achieving this. Few simple approaches can be:

1. Serve the data as a simple WMS layer and use a GetFeatureInfo request. For OpenLayers see docs and example. For mapserver see docs. Even better, have a look at what something like MapProxy can offer. With this solution you can completely bypass MapServer templates and php.

2. Serve the data as simple tile images. For OpenLayers have a look at XYZ and TMS layers, for example. And for generating the tiles, again, have a look into MapProxy. Once this is set-up, you can then fire a simple Ajax request to the server on a click event, passing the x-y coordinates. Have a look at this example for the click event. Whatever you do on the server for constructing your response is up to you.

3. Serve the data as a geoJSON and create a vector layer. See a vector example here. This is a completely different scenario, your data is now in the browser, what you do with it in JavaScript and with the OpenLayers API is up to you.

There are other solutions and this is just a very simple overview. Hope it gives you some input to start with though. :)