shaungrady/angular-http-etag

export default httpEtagInterceptorFactory

function httpEtagInterceptorFactory () {
  function responseInterceptor (response) {
    var itemCache = response.config.$$_itemCache

    if (itemCache) {
      var cacheInfo = itemCache.info()
      var cacheResponseData = cacheInfo.cacheResponseData
      var etag = response.headers().etag
      var cacheData = {}

      if (etag) {
        cacheData.etagHeader = etag
        if (cacheResponseData) cacheData.responseData = response.data
        itemCache.$set(cacheData)
      }

      delete response.config.$$_itemCache
    }

    return response
  }

  return {
    response: responseInterceptor
  }
}