Add RPM registry (#23380)

Fixes #20751

This PR adds a RPM package registry. You can follow [this
tutorial](https://opensource.com/article/18/9/how-build-rpm-packages) to
build a *.rpm package for testing.

This functionality is similar to the Debian registry (#22854) and
therefore shares some methods. I marked this PR as blocked because it
should be merged after #22854.


![grafik](https://user-images.githubusercontent.com/1666336/223806549-d8784fd9-9d79-46a2-9ae2-f038594f636a.png)

2 files changed, 119 insertions, 0 deletions

diff --git a/docs/content/doc/usage/packages/overview.en-us.md b/docs/content/doc/usage/packages/overview.en-us.md
index 8e4fd87e7b..8a70a352eb 100644
--- a/docs/content/doc/usage/packages/overview.en-us.md
+++ b/docs/content/doc/usage/packages/overview.en-us.md
@@ -41,6 +41,7 @@ The following package managers are currently supported:
 | [NuGet]({{< relref "doc/usage/packages/nuget.en-us.md" >}}) | .NET | `nuget` |
 | [Pub]({{< relref "doc/usage/packages/pub.en-us.md" >}}) | Dart | `dart`, `flutter` |
 | [PyPI]({{< relref "doc/usage/packages/pypi.en-us.md" >}}) | Python | `pip`, `twine` |
+| [RPM]({{< relref "doc/usage/packages/rpm.en-us.md" >}}) | - | `yum`, `dnf` |
 | [RubyGems]({{< relref "doc/usage/packages/rubygems.en-us.md" >}}) | Ruby | `gem`, `Bundler` |
 | [Swift]({{< relref "doc/usage/packages/rubygems.en-us.md" >}}) | Swift | `swift` |
 | [Vagrant]({{< relref "doc/usage/packages/vagrant.en-us.md" >}}) | - | `vagrant` |
diff --git a/docs/content/doc/usage/packages/rpm.en-us.md b/docs/content/doc/usage/packages/rpm.en-us.md
new file mode 100644
index 0000000000..c916014bdb
--- /dev/null
+++ b/docs/content/doc/usage/packages/rpm.en-us.md
@@ -0,0 +1,118 @@
+---
+date: "2023-03-08T00:00:00+00:00"
+title: "RPM Packages Repository"
+slug: "packages/rpm"
+draft: false
+toc: false
+menu:
+  sidebar:
+    parent: "packages"
+    name: "RPM"
+    weight: 105
+    identifier: "rpm"
+---
+
+# RPM Packages Repository
+
+Publish [RPM](https://rpm.org/) packages for your user or organization.
+
+**Table of Contents**
+
+{{< toc >}}
+
+## Requirements
+
+To work with the RPM registry, you need to use a package manager like `yum` or `dnf` to consume packages.
+
+The following examples use `dnf`.
+
+## Configuring the package registry
+
+To register the RPM registry add the url to the list of known apt sources:
+
+```shell
+dnf config-manager --add-repo https://gitea.example.com/api/packages/{owner}/rpm.repo
+```
+
+| Placeholder | Description |
+| ----------- | ----------- |
+| `owner`     | The owner of the package. |
+
+If the registry is private, provide credentials in the url. You can use a password or a [personal access token]({{< relref "doc/developers/api-usage.en-us.md#authentication" >}}):
+
+```shell
+dnf config-manager --add-repo https://{username}:{your_password_or_token}@gitea.example.com/api/packages/{owner}/rpm.repo
+```
+
+You have to add the credentials to the urls in the `rpm.repo` file in `/etc/yum.repos.d` too.
+
+## Publish a package
+
+To publish a RPM package (`*.rpm`), perform a HTTP PUT operation with the package content in the request body.
+
+```
+PUT https://gitea.example.com/api/packages/{owner}/rpm/upload
+```
+
+| Parameter | Description |
+| --------- | ----------- |
+| `owner`   | The owner of the package. |
+
+Example request using HTTP Basic authentication:
+
+```shell
+curl --user your_username:your_password_or_token \
+     --upload-file path/to/file.rpm \
+     https://gitea.example.com/api/packages/testuser/rpm/upload
+```
+
+If you are using 2FA or OAuth use a [personal access token]({{< relref "doc/developers/api-usage.en-us.md#authentication" >}}) instead of the password.
+You cannot publish a file with the same name twice to a package. You must delete the existing package version first.
+
+The server reponds with the following HTTP Status codes.
+
+| HTTP Status Code  | Meaning |
+| ----------------- | ------- |
+| `201 Created`     | The package has been published. |
+| `400 Bad Request` | The package is invalid. |
+| `409 Conflict`    | A package file with the same combination of parameters exist already in the package. |
+
+## Delete a package
+
+To delete a Debian package perform a HTTP DELETE operation. This will delete the package version too if there is no file left.
+
+```
+DELETE https://gitea.example.com/api/packages/{owner}/rpm/{package_name}/{package_version}/{architecture}
+```
+
+| Parameter         | Description |
+| ----------------- | ----------- |
+| `owner`           | The owner of the package. |
+| `package_name`    | The package name. |
+| `package_version` | The package version. |
+| `architecture`    | The package architecture. |
+
+Example request using HTTP Basic authentication:
+
+```shell
+curl --user your_username:your_token_or_password -X DELETE \
+     https://gitea.example.com/api/packages/testuser/rpm/test-package/1.0.0/x86_64
+```
+
+The server reponds with the following HTTP Status codes.
+
+| HTTP Status Code  | Meaning |
+| ----------------- | ------- |
+| `204 No Content`  | Success |
+| `404 Not Found`   | The package or file was not found. |
+
+## Install a package
+
+To install a package from the RPM registry, execute the following commands:
+
+```shell
+# use latest version
+dnf install {package_name}
+# use specific version
+dnf install {package_name}-{package_version}.{architecture}
+```