从Python到Google Maps实现渐进式可视化？

Question

I'm mostly working on backend staff, except now in a project I need to use python to do computing and visualize the results on google maps. Think about it as, for example, compute the geographical clusters of people tweeting in new york city.

In the python program, it runs about 10 seconds, and then output one iteration of data, which is a json object for coordinates. I'm wondering how should I connect this data to google maps?

What I thought was let python write data into a file and JS would listen to that file every few milliseconds. However that sounds too hacky. Just wondering is there a better way to do it?

I'm really a newbie to js. please forgive my ignorance.

Thanks

Answer 1

The normal way a HTML page gets data from a backend service (like your coordinate generator every 10 seconds) is to poll a web service (usually, a JSON feed) for updates.

All of the dynamic Google Maps stuff happens within a browser, and that page polls a JSON endpoint, or uses something fancier like websockets to stream data into the browser window.

For the frontend, consider using jQuery , which makes polling JSON dead simple. Here's some examples.

Your "python program" should dump results into a simple database. While relational and traditional databases like MySQL or PostgreSQL should suffice, i'd encourage you to use a NoSQL database, which handles capped collections . This prevents you from having to clean old data out from a cron schedule. It additionally allows storing data in ranged buckets for some cool playback style histories.

You should then have a simple web server which can handle the JSON requests from the HTML frontend page, and simply pulls data from the MongoDB. This can be done quickly in any one of the python web frameworks like Flask , Bottle or Pyramid . You could also play with something a little sexier like node.js . The only requirement here is that a database driver exists for it.

Hope that gives a 10,000 foot view of what you need to do now.