First version of admin API (#298)

**Spec:**

- [x] Start writing
- [x] Specify all layout endpoints
- [x] Specify all endpoints for operations on keys
- [x] Specify all endpoints for operations on key/bucket permissions
- [x] Specify all endpoints for operations on buckets
- [x] Specify all endpoints for operations on bucket aliases

View rendered spec at <https://git.deuxfleurs.fr/Deuxfleurs/garage/src/branch/admin-api/doc/drafts/admin-api.md>

**Code:**

- [x] Refactor code for admin api to use common api code that was created for K2V

**General endpoints:**

- [x] Metrics
- [x] GetClusterStatus
- [x] ConnectClusterNodes
- [x] GetClusterLayout
- [x] UpdateClusterLayout
- [x] ApplyClusterLayout
- [x] RevertClusterLayout

**Key-related endpoints:**

- [x] ListKeys
- [x] CreateKey
- [x] ImportKey
- [x] GetKeyInfo
- [x] UpdateKey
- [x] DeleteKey

**Bucket-related endpoints:**

- [x] ListBuckets
- [x] CreateBucket
- [x] GetBucketInfo
- [x] DeleteBucket
- [x] PutBucketWebsite
- [x] DeleteBucketWebsite

**Operations on key/bucket permissions:**

- [x] BucketAllowKey
- [x] BucketDenyKey

**Operations on bucket aliases:**

- [x] GlobalAliasBucket
- [x] GlobalUnaliasBucket
- [x] LocalAliasBucket
- [x] LocalUnaliasBucket

**And also:**

- [x] Separate error type for the admin API (this PR includes a quite big refactoring of error handling)
- [x] Add management of website access
- [ ] Check that nothing is missing wrt what can be done using the CLI
- [ ] Improve formatting of the spec
- [x] Make sure everyone is cool with the API design

Fix #231
Fix #295

Co-authored-by: Alex Auvolat <alex@adnab.me>
Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/298
Co-authored-by: Alex <alex@adnab.me>
Co-committed-by: Alex <alex@adnab.me>

1 files changed, 36 insertions, 0 deletions

diff --git a/src/api/signature/error.rs b/src/api/signature/error.rs
new file mode 100644
index 00000000..f5a067bd
--- /dev/null
+++ b/src/api/signature/error.rs
@@ -0,0 +1,36 @@
+use err_derive::Error;
+
+use crate::common_error::CommonError;
+pub use crate::common_error::{CommonErrorDerivative, OkOrBadRequest, OkOrInternalError};
+
+/// Errors of this crate
+#[derive(Debug, Error)]
+pub enum Error {
+	#[error(display = "{}", _0)]
+	/// Error from common error
+	Common(CommonError),
+
+	/// Authorization Header Malformed
+	#[error(display = "Authorization header malformed, expected scope: {}", _0)]
+	AuthorizationHeaderMalformed(String),
+
+	// Category: bad request
+	/// The request contained an invalid UTF-8 sequence in its path or in other parameters
+	#[error(display = "Invalid UTF-8: {}", _0)]
+	InvalidUtf8Str(#[error(source)] std::str::Utf8Error),
+
+	/// The client sent a header with invalid value
+	#[error(display = "Invalid header value: {}", _0)]
+	InvalidHeader(#[error(source)] hyper::header::ToStrError),
+}
+
+impl<T> From<T> for Error
+where
+	CommonError: From<T>,
+{
+	fn from(err: T) -> Self {
+		Error::Common(CommonError::from(err))
+	}
+}
+
+impl CommonErrorDerivative for Error {}