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Overcoming CORS while testing SPA locally

One of the common problems you common across while developing SPA or hybrid mobile apps locally is that when you make a cross domain API call, this is what you get in your console window


XMLHttpRequest cannot load http://jsonplaceholder.typicode.com/. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8100' is therefore not allowed access. 

The reason for this is the browser security is preventing cross domain Ajax call. You can read more about CORS here.

As a developer you don't want to worry about this and you just want to drink your coffee, write awesome code and test it your machine.

Cool! I do the same!

Here is a little secret. You can tell Chrome to ignore the security and allow cross domain request. To do this, create a new shortcut for Chrome and pass these parameters.
  --disable-web-security --user-Agent="Android" --user-data-dir="c:/temp-chrome-eng"

user-Agent is optional but other two are required to make it work. So your shortcut should look like this

"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --disable-web-security --user-Agent="Android" --user-data-dir="c:/temp-chrome-eng"

Name the short cut as Chrome-X-Domain to make it obvious that you are running under less security. Now click on the shortcut to start the browser. Chrome will warn you that you are using unsupported command line. You can ignore that. Now fire up your application and you can make cross domain api calls.

Please leave a comment or share this post if you found it useful and if it saved you hours scratching your head on how to test cross domain api calls.

Happy programming!


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