async fn get_download_url_for_layer(
        &self,
        input: GetDownloadUrlForLayerRequest,
    ) -> Result<GetDownloadUrlForLayerResponse, RusotoError<GetDownloadUrlForLayerError>> {
        let mut request = self.new_signed_request("POST", "/");
        request.add_header(
            "x-amz-target",
            "AmazonEC2ContainerRegistry_V20150921.GetDownloadUrlForLayer",
        );
        let encoded = serde_json::to_string(&input).unwrap();
        request.set_payload(Some(encoded));

        let response = self
            .sign_and_dispatch(request, GetDownloadUrlForLayerError::from_response)
            .await?;
        let mut response = response;
        let response = response.buffer().await.map_err(RusotoError::HttpDispatch)?;
        proto::json::ResponsePayload::new(&response)
            .deserialize::<GetDownloadUrlForLayerResponse, _>()
    }
<p><p>Retrieves the pre-signed Amazon S3 download URL corresponding to an image layer. You can only get URLs for image layers that are referenced in an image.</p> <p>When an image is pulled, the GetDownloadUrlForLayer API is called once per image layer that is not already cached.</p> <note> <p>This operation is used by the Amazon ECR proxy and is not generally used by customers for pulling and pushing images. In most cases, you should use the <code>docker</code> CLI to pull, tag, and push images.</p> </note></p>
rusoto/services/ecr/src/generated.rs