1
0
mirror of https://github.com/distribution/distribution synced 2024-12-25 15:05:51 +01:00

feat: implement 'rewrite' storage middleware

This allows to rewrite 'URLFor' of the storage driver to use a specific
host/trim the base path.

It is different from the 'redirect' middleware, as it still calls the
storage driver URLFor.

For example, with Azure storage provider, this allows to transform the
SAS Azure Blob Storage URL into the URL compatible with Azure Front
Door.

Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>
This commit is contained in:
Andrey Smirnov 2023-10-31 22:59:42 +04:00
parent 3a8499541a
commit 558ace1391
No known key found for this signature in database
GPG Key ID: FE042E3D4085A811
5 changed files with 209 additions and 0 deletions

@ -14,6 +14,7 @@ import (
_ "github.com/distribution/distribution/v3/registry/storage/driver/inmemory"
_ "github.com/distribution/distribution/v3/registry/storage/driver/middleware/cloudfront"
_ "github.com/distribution/distribution/v3/registry/storage/driver/middleware/redirect"
_ "github.com/distribution/distribution/v3/registry/storage/driver/middleware/rewrite"
_ "github.com/distribution/distribution/v3/registry/storage/driver/s3-aws"
)

@ -0,0 +1,15 @@
---
description: Explains how to use storage middleware
keywords: registry, on-prem, images, tags, repository, distribution, storage drivers, advanced
title: Storage middleware
---
This document describes the registry storage middleware.
## Provided middleware
This storage driver package comes bundled with several middleware options:
- cloudfront
- redirect
- [rewrite](rewrite): Partially rewrites the URL returned by the storage driver.

@ -0,0 +1,32 @@
---
description: Explains how to use the rewrite storage middleware
keywords: registry, service, driver, images, storage, middleware, rewrite
title: Rewrite middleware
---
A storage middleware which allows to rewrite the URL returned by the storage driver.
For example, it can be used to rewrite the Blob Storage URL returned by the Azure Blob Storage driver to use Azure CDN.
## Parameters
* `scheme`: (optional): Rewrite the returned URL scheme (if set).
* `host`: (optional): Rewrite the returned URL host (if set).
* `trimpathprefix` (optional): Trim the prefix from the returned URL path (if set).
## Example configuration
```yaml
storage:
azure:
accountname: "ACCOUNT_NAME"
accountkey: "******"
container: container-name
middleware:
storage:
- name: rewrite
options:
scheme: https
host: example-cdn-endpoint.azurefd.net
trimpathprefix: /container-name
```

@ -0,0 +1,86 @@
package middleware
import (
"context"
"fmt"
"net/http"
"net/url"
"strings"
storagedriver "github.com/distribution/distribution/v3/registry/storage/driver"
storagemiddleware "github.com/distribution/distribution/v3/registry/storage/driver/middleware"
"github.com/sirupsen/logrus"
)
func init() {
if err := storagemiddleware.Register("rewrite", newRewriteStorageMiddleware); err != nil {
logrus.Errorf("tailed to register redirect storage middleware: %v", err)
}
}
type rewriteStorageMiddleware struct {
storagedriver.StorageDriver
overrideScheme string
overrideHost string
trimPathPrefix string
}
var _ storagedriver.StorageDriver = &rewriteStorageMiddleware{}
func getStringOption(key string, options map[string]interface{}) (string, error) {
o, ok := options[key]
if !ok {
return "", nil
}
s, ok := o.(string)
if !ok {
return "", fmt.Errorf("%s must be a string", key)
}
return s, nil
}
func newRewriteStorageMiddleware(ctx context.Context, sd storagedriver.StorageDriver, options map[string]interface{}) (storagedriver.StorageDriver, error) {
var err error
r := &rewriteStorageMiddleware{StorageDriver: sd}
if r.overrideScheme, err = getStringOption("scheme", options); err != nil {
return nil, err
}
if r.overrideHost, err = getStringOption("host", options); err != nil {
return nil, err
}
if r.trimPathPrefix, err = getStringOption("trimpathprefix", options); err != nil {
return nil, err
}
return r, nil
}
func (r *rewriteStorageMiddleware) RedirectURL(req *http.Request, path string) (string, error) {
storagePath, err := r.StorageDriver.RedirectURL(req, path)
if err != nil {
return "", err
}
u, err := url.Parse(storagePath)
if err != nil {
return "", err
}
if r.overrideScheme != "" {
u.Scheme = r.overrideScheme
}
if r.overrideHost != "" {
u.Host = r.overrideHost
}
if r.trimPathPrefix != "" {
u.Path = strings.TrimPrefix(u.Path, r.trimPathPrefix)
}
return u.String(), nil
}

@ -0,0 +1,75 @@
package middleware
import (
"context"
"net/http"
"testing"
"github.com/distribution/distribution/v3/registry/storage/driver/base"
"github.com/stretchr/testify/require"
)
type mockSD struct {
base.Base
}
func (*mockSD) RedirectURL(_ *http.Request, urlPath string) (string, error) {
return "http://some.host/some/path/file", nil
}
func TestNoConfig(t *testing.T) {
options := make(map[string]interface{})
middleware, err := newRewriteStorageMiddleware(context.Background(), &mockSD{}, options)
require.NoError(t, err)
_, ok := middleware.(*rewriteStorageMiddleware)
require.True(t, ok)
url, err := middleware.RedirectURL(nil, "")
require.NoError(t, err)
require.Equal(t, "http://some.host/some/path/file", url)
}
func TestWrongType(t *testing.T) {
options := map[string]interface{}{
"scheme": 1,
}
_, err := newRewriteStorageMiddleware(context.TODO(), nil, options)
require.ErrorContains(t, err, "scheme must be a string")
}
func TestRewriteHostsScheme(t *testing.T) {
options := map[string]interface{}{
"scheme": "https",
"host": "example.com",
}
middleware, err := newRewriteStorageMiddleware(context.TODO(), &mockSD{}, options)
require.NoError(t, err)
m, ok := middleware.(*rewriteStorageMiddleware)
require.True(t, ok)
require.Equal(t, "https", m.overrideScheme)
require.Equal(t, "example.com", m.overrideHost)
url, err := middleware.RedirectURL(nil, "")
require.NoError(t, err)
require.Equal(t, "https://example.com/some/path/file", url)
}
func TestTrimPrefix(t *testing.T) {
options := map[string]interface{}{
"trimpathprefix": "/some/path",
}
middleware, err := newRewriteStorageMiddleware(context.TODO(), &mockSD{}, options)
require.NoError(t, err)
m, ok := middleware.(*rewriteStorageMiddleware)
require.True(t, ok)
require.Equal(t, "/some/path", m.trimPathPrefix)
url, err := middleware.RedirectURL(nil, "")
require.NoError(t, err)
require.Equal(t, "http://some.host/file", url)
}