3 files changed, 109 insertions, 0 deletions
diff --git a/src/model/helper/bucket.rs b/src/model/helper/bucket.rs
new file mode 100644
index 00000000..e89a723d
--- /dev/null
+++ b/src/model/helper/bucket.rs
@@ -0,0 +1,56 @@
+use garage_table::util::EmptyKey;
+use garage_util::data::*;
+
+use crate::bucket_table::Bucket;
+use crate::garage::Garage;
+use crate::helper::error::*;
+
+pub struct BucketHelper<'a>(pub(crate) &'a Garage);
+
+impl<'a> BucketHelper<'a> {
+	#[allow(clippy::ptr_arg)]
+	pub async fn resolve_global_bucket_name(
+		&self,
+		bucket_name: &String,
+	) -> Result<Option<Uuid>, Error> {
+		// Bucket names in Garage are aliases, true bucket identifiers
+		// are 32-byte UUIDs. This function resolves bucket names into
+		// their full identifier by looking up in the bucket_alias_table.
+		// This function also allows buckets to be identified by their
+		// full UUID (hex-encoded). Here, if the name to be resolved is a
+		// hex string of the correct length, it is directly parsed as a bucket
+		// identifier which is returned. There is no risk of this conflicting
+		// with an actual bucket name: bucket names are max 63 chars long by
+		// the AWS spec, and hex-encoded UUIDs are 64 chars long.
+		let hexbucket = hex::decode(bucket_name.as_str())
+			.ok()
+			.map(|by| Uuid::try_from(&by))
+			.flatten();
+		if let Some(bucket_id) = hexbucket {
+			Ok(self
+				.0
+				.bucket_table
+				.get(&bucket_id, &EmptyKey)
+				.await?
+				.filter(|x| !x.state.is_deleted())
+				.map(|_| bucket_id))
+		} else {
+			Ok(self
+				.0
+				.bucket_alias_table
+				.get(&EmptyKey, bucket_name)
+				.await?
+				.map(|x| x.state.get().as_option().map(|x| x.bucket_id))
+				.flatten())
+		}
+	}
+
+	pub async fn get_existing_bucket(&self, bucket_id: Uuid) -> Result<Bucket, Error> {
+		self.0
+			.bucket_table
+			.get(&bucket_id, &EmptyKey)
+			.await?
+			.filter(|b| !b.is_deleted())
+			.ok_or_bad_request(format!("Bucket {:?} does not exist", bucket_id))
+	}
+}
diff --git a/src/model/helper/error.rs b/src/model/helper/error.rs
new file mode 100644
index 00000000..b9b515f3
--- /dev/null
+++ b/src/model/helper/error.rs
@@ -0,0 +1,51 @@
+use err_derive::Error;
+use serde::{Deserialize, Serialize};
+
+use garage_util::error::Error as GarageError;
+
+#[derive(Debug, Error, Serialize, Deserialize)]
+pub enum Error {
+	#[error(display = "Internal error: {}", _0)]
+	Internal(#[error(source)] GarageError),
+
+	#[error(display = "Bad request: {}", _0)]
+	BadRequest(String),
+}
+
+impl From<netapp::error::Error> for Error {
+	fn from(e: netapp::error::Error) -> Self {
+		Error::Internal(GarageError::Netapp(e))
+	}
+}
+
+pub trait OkOrBadRequest {
+	type S;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<Self::S, Error>;
+}
+
+impl<T, E> OkOrBadRequest for Result<T, E>
+where
+	E: std::fmt::Display,
+{
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, Error> {
+		match self {
+			Ok(x) => Ok(x),
+			Err(e) => Err(Error::BadRequest(format!(
+				"{}: {}",
+				reason.as_ref(),
+				e.to_string()
+			))),
+		}
+	}
+}
+
+impl<T> OkOrBadRequest for Option<T> {
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, Error> {
+		match self {
+			Some(x) => Ok(x),
+			None => Err(Error::BadRequest(reason.as_ref().to_string())),
+		}
+	}
+}
diff --git a/src/model/helper/mod.rs b/src/model/helper/mod.rs
new file mode 100644
index 00000000..2f4e8898
--- /dev/null
+++ b/src/model/helper/mod.rs
@@ -0,0 +1,2 @@
+pub mod bucket;
+pub mod error;