Method download_change_layers

atomic-remote/src/http/download.rs:109–153

Download a change with layer-selective filtering. Uses the `?layers=` query parameter to request only specific layers from the server. This enables: - **Thin pull** (`layers=graph,content`): Download only what's needed to apply the change, skipping the semantic layer (~40% smaller). - **Thin review** (`layers=semantic,content`): Download only what's needed for code review, skipping graph ops (~6

(
        &self,
        hash: &str,
        layers: &LayerSelection,
    )

    /// The raw change data (may be a subset of the full change if the
    /// server supports layer-selective responses).
    pub async fn download_change_layers(
        &self,
        hash: &str,
        layers: &LayerSelection,
    ) -> RemoteResult<Bytes> {
        let layers_param = layers.to_query_value();
        let url = format!("{}?change={}&layers={}", self.base_url, hash, layers_param);
        debug!("GET change (layers={}): {}", layers_param, url);

        let response = self
            .client
            .get(&url)
            .send()
            .await
            .map_err(|e| RemoteError::connection_failed(&url, e))?;

        crate::check_min_version_header(response.headers());
        let status = response.status();

        match status {
            StatusCode::OK => {
                let bytes = response
                    .bytes()
                    .await
                    .map_err(|e| RemoteError::connection_failed(&url, e))?;

                debug!(
                    "Downloaded change {} (layers={}): {} bytes",
                    hash,
                    layers_param,
                    bytes.len()
                );
                Ok(bytes)
            }
            StatusCode::NOT_FOUND => Err(RemoteError::change_not_found(hash)),
            StatusCode::UNAUTHORIZED | StatusCode::FORBIDDEN => {
                let msg = response.text().await.unwrap_or_default();
                Err(RemoteError::auth_failed(&url, msg))
            }
            _ => {
                let msg = response.text().await.unwrap_or_default();
                Err(RemoteError::http(status.as_u16(), msg))
            }
        }
    }

    /// Get the chunk manifest for a change.
    ///