AWS API Gateway with Angular native $http service
<p>I have AWS API gateway that uses cognito temporary credentials. 
I want to setup angular native $http service to use api with required aws4 authentication headers. 
I tried to use <a href="https://github.com/mhart/aws4" rel="nofollow">https://github.com/mhart/aws4</a> but I'm getting <code>InvalidSignatureException</code></p>

<p>Is there any way to generate aws4 auth headers for front-end applications? Does anyone have experience setting app API Gateway without autogenerated SDK?</p>