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, 4 insertions, 3 deletions

diff --git a/src/api/signature/mod.rs b/src/api/signature/mod.rs
index 5646f4fa..dd5b590c 100644
--- a/src/api/signature/mod.rs
+++ b/src/api/signature/mod.rs
@@ -4,11 +4,12 @@ use sha2::Sha256;
 
 use garage_util::data::{sha256sum, Hash};
 
-use crate::error::*;
-
+pub mod error;
 pub mod payload;
 pub mod streaming;
 
+use error::*;
+
 pub const SHORT_DATE: &str = "%Y%m%d";
 pub const LONG_DATETIME: &str = "%Y%m%dT%H%M%SZ";
 
@@ -16,7 +17,7 @@ type HmacSha256 = Hmac<Sha256>;
 
 pub fn verify_signed_content(expected_sha256: Hash, body: &[u8]) -> Result<(), Error> {
 	if expected_sha256 != sha256sum(body) {
-		return Err(Error::BadRequest(
+		return Err(Error::bad_request(
 			"Request content hash does not match signed hash".to_string(),
 		));
 	}