HTTP POST call embedded in a static html page - html

Question

I want to embed an HTTP call which returns a png image into an html page.
I will run the page on github's gh-pages if that makes a difference.
The url is: http://public.opencpu.org/R/user/SChamberlain/ropensci_dash/apistatus10/png
Note that sometimes the url doesn't return the png as the service is sometimes down.
I want to call that url using POST method, and simply return the png into the page. Ideally the http call would be run on page recycle as well.
Do I use an iframe, form, javascript?
Thanks! Scott

Answer 1

[I might as well answer properly]
When a server is feeding you image data and you want to load it, you might as well treat it like an image and use an img tag. The problem with this approach in your particular case is that you said that the server can sometimes be down and this would mean that if you simply appended the image without checking for a broken link first you will get that ugly broken image space.
However, the simplicity of using an image is still feasible. By using a little javascript with a load event handler you can append the image if and only if it loads successfully. If you get any kind of error code from the request the load event will never fire and you won't append a broken image.
Here's the concept in vanilla-js:
img = document.createElement("img");
img.onload = function(e){document.getElementsByTagName("body")[0].appendChild(img);};
img.src = "http://public.opencpu.org/R/user/SChamberlain/ropensci_dash/apistatus10/png";
You can also see it in action here: http://jsfiddle.net/BwJeC/

Answer 2

You could use XHR to load the binary data from the external, dynamic page and set the content of the image.
This question, is very much similar
Or this

Answer 3

I really don't understand why you want to POST.
Anyway if you want to query a picture with a POST data you could, may have to do a Js XHR call and return the the image as base64 and then do something like:
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" />
The best would still be to to a simple get call:
<img src="/dynamicallyGeneratedPicture" />
with a route or script that return a document of type image.