restRequest.cmp

<aura:component controller="paura.RestRequestController">
    
    <aura:attribute name="path" type="String" required="true" />
    <aura:attribute name="method" type="String" default="GET"/>
    <aura:attribute name="responseFormat" type="String" default="application/json"/>
    <aura:attribute name="bodyContent" type="Object" />
    <aura:attribute name="bodyContentType" type="String" default="application/json"/>
    
    <aura:handler name="init" value="{!this}" action="{!c.makeRequest}"/>
    
    <aura:registerEvent name="restResponseEvent" type="paura:restResponseEvent"/>
    
</aura:component>

RestRequestController.cls

public class RestRequestController {

    @AuraEnabled
    public static Response service(String path, String method, String responseFormat, String bodyContent, String bodyContentType) {
        HttpRequest request = buildRequest(path, method, responseFormat, bodyContent, bodyContentType);
        HttpResponse httpRes = sendRequest(request);
        Response restRes = buildResponse(httpRes);
        
        return restRes;
    }
    
    private static HttpRequest buildRequest(String path, String method, String responseFormat, String bodyContent, String bodyContentType) {
        HttpRequest request = new HttpRequest();
        
        request.setEndpoint(URL.getSalesforceBaseUrl().toExternalForm() + path);
        request.setMethod(method);
        
        if (bodyContent != null) {
            request.setBody(bodyContent);
            request.setHeader('Content-Type', bodyContentType); 
        }
        
        request.setHeader('Authorization', 'Bearer ' + UserInfo.getSessionId());
        request.setHeader('ACCEPT', responseFormat);
        
        return request;
    }
      
    private static HttpResponse sendRequest(HttpRequest request) {    
        return new Http().send(request);
    }
    
    private static Response buildResponse(HttpResponse httpRes) {
        Response restRes = new Response();
        
        restRes.status = httpRes.getStatus();
        restRes.statusCode = httpRes.getStatusCode();
        restRes.body = httpRes.getBody();
        
        return restRes;
    }

    public class Response {

        @AuraEnabled
        public String status { get; set; }
        
        @AuraEnabled
        public Integer statusCode { get; set; }
        
        @AuraEnabled
        public String body { get; set; }
    }
}

restRequestController.js

({
	makeRequest : function(component, event, helper) {
        var action = component.get("c.service");
        
        action.setParams({
            path: component.get("v.path"),
            method: component.get("v.method"),
            responseFormat: component.get("v.responseFormat"),
            bodyContent: component.get("v.bodyContent"),
            bodyContentType: component.get("v.bodyContentType")
        });
        
        action.setCallback(this, function(a) {
        	component.getEvent("restResponseEvent").setParams({
            	response: a.getReturnValue()
        	}).fire(); 
        });
        
        $A.enqueueAction(action);
	}
})

restResponseEvent.evt

<aura:event type="COMPONENT" description="Event fired when a response from a restRequest is available">
    <aura:attribute name="response" type="Object" description="The response" />
</aura:event>

widgets.app

<aura:application>

<!-- DYNAMIC INVOCATION
    <select aura:id="reportId" onchange="{!c.setPath}">
    	<option value="00Oi0000006qd21">Owners</option>
        <option value="00Oi000007sq320">Web Leads per Day</option>
    </select>
-->
    <paura:restRequest aura:id="restCmp"
        path="/services/data/v32.0/analytics/reports/00Oi0000006qd21/describe"           
        restResponseEvent="{!c.handleResponse}"
    />  
    
<!-- INSERT
    <paura:restRequest
        path="/services/data/v32.0/sobjects/Account/" 
        method="POST"
        bodyContent="{ &quot;Name&quot; : &quot;A new Account&quot; }"
        restResponseEvent="{!c.handleResponse}"
    />
-->
    
<!-- DYNAMIC COMPONENT CREATION
    <ui:button label="Describe the report" press="{!c.describeTheReport}"/>
-->
    
</aura:application>

widgetsController.js

({
    handleResponse: function(component, event, helper) {
        var response = event.getParam("response");
        var status = response.status;
        var statusCode = response.statusCode;
        var body = response.body;
        // do something interesting...
        // 
        console.log(body);
    },
    
    setPath: function(component, event, helper) {
        var selectElem = component.find("reportId").getElement();
        var reptId = selectElem.options[selectElem.selectedIndex].value;
      
        var restCmp = component.find("restCmp");
        restCmp.set("v.path", "/services/data/v32.0/analytics/reports/" + reptId + "/describe");
        
        var a = restCmp.get("c.makeRequest");
        $A.enqueueAction(a);
    },
    
    describeTheReport: function(component, event, helper) {
        
        var componentConfig = {
            componentDef : "markup://paura:restRequest",
            attributes : {
                values : {
                    path : "/services/data/v32.0/analytics/reports/00Oi0000006qd21/describe",
                } 
            }
        };
        
        $A.componentService.newComponentAsync(
            this,
            function(newCmp) {
                newCmp.addHandler("restResponseEvent", component, "c.handleResponse");
                var a = newCmp.get("c.makeRequest");
                $A.enqueueAction(a);
            },
            componentConfig
        );
    }
})