rendering multiline Javascript by using JSONP in rails

Question

Hello,

In a controller I try to render a javascript google ad to print it into some HTML using JSONP, like this

<script type="text/javascript"><!--
google_ad_client = "pub-23222424";
google_alternate_color = "FFFFFF";
google_ad_width = 468;
google_ad_height = 60;
//--></script>
<script type="text/javascript"
  src="http://pagead2.google.com/pgad/show_ads.js"&gt;
</script>

So I do:

render :text "var s_response = { content: '<script type=\"text/javascript\"><!--\\ngoogle_ad_client = \"pub-23222424\";\\ngoogle_alternate_color = \"FFFFFF\";\\ngoogle_ad_width = 468;\\ngoogle_ad_height = 60;\\n//--><\\/script>\\n<script type=\"text/javascript\"\\n  src=\"http://pagead2.google.com/pgad/show_ads.js\"&gt;\\n&lt;\\/script&gt;', id: '2'};">

But i get this error:

unterminated string literal

[Break on this error] var response = { content: '<script type="text/javascript"><!-- 

=> That seems like it is a multilines problem right ? But I don't know how to resolve it.

Thanks,

Lucas

Answer 1

In JavaScript, you cannot spread a string over multiple lines.

In this case, you can leave out those comments so you can put everything in a single line and get rid of the newline characters (\n).

BTW, a valid JSON response would surround every string, whether it represents a key or a value, with double quotes. Also see JSONLint's FAQ:

Proper format for a collection is: { "key": "value" }

In the end, you get:

render :text "var s_response = { \"content\": \"<script type='text/javascript'>google_ad_client = 'pub-23222424';google_alternate_color = 'FFFFFF';google_ad_width = 468;google_ad_height = 60;<\\/script><script type='text/javascript' src='http://pagead2.google.com/pgad/show_ads.js'&gt;&lt;\\/script&gt;\", \"id\": \"2\"};">

Answer 2

Write huge strings like in my example below and stop escaping them:

render :text => %{ 
    <script type="text/javascript">
    //<!--
    google_ad_client = "pub-23222424";
    google_alternate_color = "FFFFFF";
    google_ad_width = 468;
    google_ad_height = 60;
    //-->
    </script>
    <script type="text/javascript" 
            src="http://pagead2.google.com/pgad/show_ads.js"&gt;
    </script> }

Answer 3

Thanks for your responses !

Marcel > The problem is that if I get rid of the newline characters my ad can't display anymore, I tried it "manually". So I may need to replace the "/n" characters before to send the response by something like a unique string and to replace them again after the response is received by the server ?

floatless > Initially I did not escaped my response and it did not work. So I do not think it will change anything, but thanks anyway.