> > > From: bratliff > > > > > > Eliminating the use of proxies with a JSON interface > > > might appeal to some developers.
> > From: William > > > > Could you explain what you mean by "proxy" server in this > > context? That's like another server standing between the > > client browser and the server responsible for making a > > Google Map Layer? > From: bratliff > > Yes. > > If I host an application on my server, it cannot send > XMLHttpRequests to your server because of cross domain > security. It has to send XMLHttpRequests to my own server > which are repackaged & forwarded to your server. Every round > trip involves four hops. Using JSON, my application hosted > on my server can communicate directly with your server. > Every round trip involves two hops. Also, JSON is fairly > compact compared to XML. > > Some developers have neither the skills nor the privileges to > set up a proxy on their web host provider's server. To be specific, what's required for this isn't plain JSON, but JSONP, which is a JSON object wrapped inside a callback function so it is actually executable JavaScript code. The name of the callback function is specified in the URL for the data request, typically with a "callback=" parameter. For example: http://example.com/getjson?foo=bar&format=json Could return standard JSON: { "test": "howdy" } Adding a callback parameter: http://example.com/getjson?foo=bar&format=json&callback=mike Would return JSONP instead: mike({ "test": "howdy" }) That is a JavaScript function call which is directly executable, unlike the standard JSON which is not. Making it an executable function call is what allows it to work cross-domain (since browsers allow scripts to be loaded from any domain). -Mike --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Maps API" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/Google-Maps-API?hl=en -~----------~----~----~----~------~----~------~--~---
