style: Define error variants instead of using unwrap()

crates/bpf-common/src/containers/layers.rs

@@ -80,12 +80,27 @@ struct Rootfs {
 /// Returns a list of layer paths for the given Docker image ID.
 pub(crate) async fn docker_layers(image_id: &str) -> Result<Vec<PathBuf>, ContainerError> {
  let client = Client::unix();
- let url = HyperlocalUri::new(DOCKER_SOCKET, &format!("/images/{}/json", image_id));
-
- let response = client.get(url.into()).await.unwrap();
- let body_bytes = body::to_bytes(response).await.unwrap();
-
- let response: ImageInspect = serde_json::from_slice(&body_bytes).unwrap();
+ let uri = HyperlocalUri::new(DOCKER_SOCKET, &format!("/images/{}/json", image_id));
+ let uri: hyper::Uri = uri.into();
+
+ let response =
+ client
+ .get(uri.clone())
+ .await
+ .map_err(|source| ContainerError::HyperRequest {
+ source,
+ uri: uri.clone(),
+ })?;
+ let body_bytes =
+ body::to_bytes(response)
+ .await
+ .map_err(|source| ContainerError::HyperResponse {
+ source,
+ uri: uri.clone(),
+ })?;
+
+ let response: ImageInspect = serde_json::from_slice(&body_bytes)
+ .map_err(|source| ContainerError::ParseResponse { source, uri })?;
 
  match response.graph_driver.name {
  GraphDriverName::Btrfs => docker_btrfs_layers(image_id),
@@ -132,7 +147,10 @@ fn docker_btrfs_layers(image_id: &str) -> Result<Vec<PathBuf>, ContainerError> {
  .map_err(|source| ContainerError::ParseConfigFile { source, path })?;
 
  for layer_id in imagedb_entry.rootfs.diff_ids {
- let layer_id = layer_id.split(':').last().unwrap();
+ let layer_id = layer_id
+ .split(':')
+ .last()
+ .ok_or(ContainerError::InvalidLayerID(layer_id.clone()))?;
 
  let path = PathBuf::from(DOCKER_LAYERDB_PATH).join(&layer_id);
  if path.exists() {
@@ -156,6 +174,7 @@ fn docker_overlayfs_layers(
  if let Some(graph_driver_data) = graph_driver_data {
  if let Some(lower_dirs) = graph_driver_data.lower_dir {
  for lower_dir in lower_dirs.split(':') {
+ // `PathBuf::from_str` is infallible.
  layers.push(PathBuf::from_str(lower_dir).unwrap());
  }
  }

crates/bpf-common/src/containers/mod.rs

@@ -41,8 +41,26 @@ pub enum ContainerError {
  source: serde_json::error::Error,
  path: PathBuf,
  },
+ #[error("parsing response from `{uri:?}` failed")]
+ ParseResponse {
+ #[source]
+ source: serde_json::error::Error,
+ uri: hyper::Uri,
+ },
  #[error("path `{path}` is non-UTF-8")]
  PathNonUtf8 { path: PathBuf },
+ #[error("failed to make a request to the UNIX socket `{uri:?}`")]
+ HyperRequest {
+ #[source]
+ source: hyper::Error,
+ uri: hyper::Uri,
+ },
+ #[error("failed to parse a response from the UNIX socket `{uri:?}`")]
+ HyperResponse {
+ #[source]
+ source: hyper::Error,
+ uri: hyper::Uri,
+ },
  #[error("could not connect to the database `{path:?}`")]
  SqliteConnection {
  #[source]
@@ -79,6 +97,10 @@ pub enum ContainerError {
  BoltBucketNotFound(String),
  #[error("bolt key `{0}` not found")]
  BoltKeyNotFound(String),
+ #[error("Invalid layer ID: `{0}`")]
+ InvalidLayerID(String),
+ #[error("Invalid image digest: `{0}`")]
+ InvalidImageDigest(String),
 }
 
 /// A container ID.
@@ -204,7 +226,10 @@ impl ContainerInfo {
  // ```
  //
  // The unprefixed digest is used as an image ID.
- let image_id = image_digest.split(':').last().unwrap();
+ let image_id = image_digest
+ .split(':')
+ .last()
+ .ok_or(ContainerError::InvalidImageDigest(image_digest.clone()))?;
 
  let layers = layers::docker_layers(image_id).await?;
  log::debug!("found layer filesystems for container {id}: {layers:?}");