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)

4 files changed, 281 insertions, 2 deletions

diff --git a/routers/api/packages/api.go b/routers/api/packages/api.go
index ee1feb1414..9b24918f51 100644
--- a/routers/api/packages/api.go
+++ b/routers/api/packages/api.go
@@ -29,6 +29,7 @@ import (
 	"code.gitea.io/gitea/routers/api/packages/nuget"
 	"code.gitea.io/gitea/routers/api/packages/pub"
 	"code.gitea.io/gitea/routers/api/packages/pypi"
+	"code.gitea.io/gitea/routers/api/packages/rpm"
 	"code.gitea.io/gitea/routers/api/packages/rubygems"
 	"code.gitea.io/gitea/routers/api/packages/swift"
 	"code.gitea.io/gitea/routers/api/packages/vagrant"
@@ -420,6 +421,16 @@ func CommonRoutes(ctx gocontext.Context) *web.Route {
 			r.Get("/files/{id}/{version}/{filename}", pypi.DownloadPackageFile)
 			r.Get("/simple/{id}", pypi.PackageMetadata)
 		}, reqPackageAccess(perm.AccessModeRead))
+		r.Group("/rpm", func() {
+			r.Get(".repo", rpm.GetRepositoryConfig)
+			r.Get("/repository.key", rpm.GetRepositoryKey)
+			r.Put("/upload", reqPackageAccess(perm.AccessModeWrite), rpm.UploadPackageFile)
+			r.Group("/package/{name}/{version}/{architecture}", func() {
+				r.Get("", rpm.DownloadPackageFile)
+				r.Delete("", reqPackageAccess(perm.AccessModeWrite), rpm.DeletePackageFile)
+			})
+			r.Get("/repodata/{filename}", rpm.GetRepositoryFile)
+		}, reqPackageAccess(perm.AccessModeRead))
 		r.Group("/rubygems", func() {
 			r.Get("/specs.4.8.gz", rubygems.EnumeratePackages)
 			r.Get("/latest_specs.4.8.gz", rubygems.EnumeratePackagesLatest)
diff --git a/routers/api/packages/nuget/nuget.go b/routers/api/packages/nuget/nuget.go
index f6143ce291..716d8a969d 100644
--- a/routers/api/packages/nuget/nuget.go
+++ b/routers/api/packages/nuget/nuget.go
@@ -585,7 +585,7 @@ func DownloadSymbolFile(ctx *context.Context) {
 
 	pfs, _, err := packages_model.SearchFiles(ctx, &packages_model.PackageFileSearchOptions{
 		OwnerID:     ctx.Package.Owner.ID,
-		PackageType: string(packages_model.TypeNuGet),
+		PackageType: packages_model.TypeNuGet,
 		Query:       filename,
 		Properties: map[string]string{
 			nuget_module.PropertySymbolID: strings.ToLower(guid),
diff --git a/routers/api/packages/rpm/rpm.go b/routers/api/packages/rpm/rpm.go
new file mode 100644
index 0000000000..73e457237a
--- /dev/null
+++ b/routers/api/packages/rpm/rpm.go
@@ -0,0 +1,268 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package rpm
+
+import (
+	stdctx "context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+
+	"code.gitea.io/gitea/models/db"
+	packages_model "code.gitea.io/gitea/models/packages"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/json"
+	"code.gitea.io/gitea/modules/notification"
+	packages_module "code.gitea.io/gitea/modules/packages"
+	rpm_module "code.gitea.io/gitea/modules/packages/rpm"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
+	"code.gitea.io/gitea/routers/api/packages/helper"
+	packages_service "code.gitea.io/gitea/services/packages"
+	rpm_service "code.gitea.io/gitea/services/packages/rpm"
+)
+
+func apiError(ctx *context.Context, status int, obj interface{}) {
+	helper.LogAndProcessError(ctx, status, obj, func(message string) {
+		ctx.PlainText(status, message)
+	})
+}
+
+// https://dnf.readthedocs.io/en/latest/conf_ref.html
+func GetRepositoryConfig(ctx *context.Context) {
+	url := fmt.Sprintf("%sapi/packages/%s/rpm", setting.AppURL, ctx.Package.Owner.Name)
+
+	ctx.PlainText(http.StatusOK, `[gitea-`+ctx.Package.Owner.LowerName+`]
+name=`+ctx.Package.Owner.Name+` - `+setting.AppName+`
+baseurl=`+url+`
+enabled=1
+gpgcheck=1
+gpgkey=`+url+`/repository.key`)
+}
+
+// Gets or creates the PGP public key used to sign repository metadata files
+func GetRepositoryKey(ctx *context.Context) {
+	_, pub, err := rpm_service.GetOrCreateKeyPair(ctx.Package.Owner.ID)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	ctx.ServeContent(strings.NewReader(pub), &context.ServeHeaderOptions{
+		ContentType: "application/pgp-keys",
+		Filename:    "repository.key",
+	})
+}
+
+// Gets a pre-generated repository metadata file
+func GetRepositoryFile(ctx *context.Context) {
+	pv, err := rpm_service.GetOrCreateRepositoryVersion(ctx.Package.Owner.ID)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	s, pf, err := packages_service.GetFileStreamByPackageVersion(
+		ctx,
+		pv,
+		&packages_service.PackageFileInfo{
+			Filename: ctx.Params("filename"),
+		},
+	)
+	if err != nil {
+		if errors.Is(err, util.ErrNotExist) {
+			apiError(ctx, http.StatusNotFound, err)
+		} else {
+			apiError(ctx, http.StatusInternalServerError, err)
+		}
+		return
+	}
+	defer s.Close()
+
+	ctx.ServeContent(s, &context.ServeHeaderOptions{
+		Filename:     pf.Name,
+		LastModified: pf.CreatedUnix.AsLocalTime(),
+	})
+}
+
+func UploadPackageFile(ctx *context.Context) {
+	upload, close, err := ctx.UploadStream()
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+	if close {
+		defer upload.Close()
+	}
+
+	buf, err := packages_module.CreateHashedBufferFromReader(upload)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+	defer buf.Close()
+
+	pck, err := rpm_module.ParsePackage(buf)
+	if err != nil {
+		if errors.Is(err, util.ErrInvalidArgument) {
+			apiError(ctx, http.StatusBadRequest, err)
+		} else {
+			apiError(ctx, http.StatusInternalServerError, err)
+		}
+		return
+	}
+
+	if _, err := buf.Seek(0, io.SeekStart); err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	fileMetadataRaw, err := json.Marshal(pck.FileMetadata)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	_, _, err = packages_service.CreatePackageOrAddFileToExisting(
+		&packages_service.PackageCreationInfo{
+			PackageInfo: packages_service.PackageInfo{
+				Owner:       ctx.Package.Owner,
+				PackageType: packages_model.TypeRpm,
+				Name:        pck.Name,
+				Version:     pck.Version,
+			},
+			Creator:  ctx.Doer,
+			Metadata: pck.VersionMetadata,
+		},
+		&packages_service.PackageFileCreationInfo{
+			PackageFileInfo: packages_service.PackageFileInfo{
+				Filename: fmt.Sprintf("%s-%s.%s.rpm", pck.Name, pck.Version, pck.FileMetadata.Architecture),
+			},
+			Creator: ctx.Doer,
+			Data:    buf,
+			IsLead:  true,
+			Properties: map[string]string{
+				rpm_module.PropertyMetadata: string(fileMetadataRaw),
+			},
+		},
+	)
+	if err != nil {
+		switch err {
+		case packages_model.ErrDuplicatePackageVersion, packages_model.ErrDuplicatePackageFile:
+			apiError(ctx, http.StatusConflict, err)
+		case packages_service.ErrQuotaTotalCount, packages_service.ErrQuotaTypeSize, packages_service.ErrQuotaTotalSize:
+			apiError(ctx, http.StatusForbidden, err)
+		default:
+			apiError(ctx, http.StatusInternalServerError, err)
+		}
+		return
+	}
+
+	if err := rpm_service.BuildRepositoryFiles(ctx, ctx.Package.Owner.ID); err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	ctx.Status(http.StatusCreated)
+}
+
+func DownloadPackageFile(ctx *context.Context) {
+	name := ctx.Params("name")
+	version := ctx.Params("version")
+
+	s, pf, err := packages_service.GetFileStreamByPackageNameAndVersion(
+		ctx,
+		&packages_service.PackageInfo{
+			Owner:       ctx.Package.Owner,
+			PackageType: packages_model.TypeRpm,
+			Name:        name,
+			Version:     version,
+		},
+		&packages_service.PackageFileInfo{
+			Filename: fmt.Sprintf("%s-%s.%s.rpm", name, version, ctx.Params("architecture")),
+		},
+	)
+	if err != nil {
+		if errors.Is(err, util.ErrNotExist) {
+			apiError(ctx, http.StatusNotFound, err)
+		} else {
+			apiError(ctx, http.StatusInternalServerError, err)
+		}
+		return
+	}
+	defer s.Close()
+
+	ctx.ServeContent(s, &context.ServeHeaderOptions{
+		ContentType:  "application/x-rpm",
+		Filename:     pf.Name,
+		LastModified: pf.CreatedUnix.AsLocalTime(),
+	})
+}
+
+func DeletePackageFile(webctx *context.Context) {
+	name := webctx.Params("name")
+	version := webctx.Params("version")
+	architecture := webctx.Params("architecture")
+
+	var pd *packages_model.PackageDescriptor
+
+	err := db.WithTx(webctx, func(ctx stdctx.Context) error {
+		pv, err := packages_model.GetVersionByNameAndVersion(ctx, webctx.Package.Owner.ID, packages_model.TypeRpm, name, version)
+		if err != nil {
+			return err
+		}
+
+		pf, err := packages_model.GetFileForVersionByName(
+			ctx,
+			pv.ID,
+			fmt.Sprintf("%s-%s.%s.rpm", name, version, architecture),
+			packages_model.EmptyFileKey,
+		)
+		if err != nil {
+			return err
+		}
+
+		if err := packages_service.DeletePackageFile(ctx, pf); err != nil {
+			return err
+		}
+
+		has, err := packages_model.HasVersionFileReferences(ctx, pv.ID)
+		if err != nil {
+			return err
+		}
+		if !has {
+			pd, err = packages_model.GetPackageDescriptor(ctx, pv)
+			if err != nil {
+				return err
+			}
+
+			if err := packages_service.DeletePackageVersionAndReferences(ctx, pv); err != nil {
+				return err
+			}
+		}
+
+		return nil
+	})
+	if err != nil {
+		if errors.Is(err, util.ErrNotExist) {
+			apiError(webctx, http.StatusNotFound, err)
+		} else {
+			apiError(webctx, http.StatusInternalServerError, err)
+		}
+		return
+	}
+
+	if pd != nil {
+		notification.NotifyPackageDelete(webctx, webctx.Doer, pd)
+	}
+
+	if err := rpm_service.BuildRepositoryFiles(webctx, webctx.Package.Owner.ID); err != nil {
+		apiError(webctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	webctx.Status(http.StatusNoContent)
+}
diff --git a/routers/api/v1/packages/package.go b/routers/api/v1/packages/package.go
index ac48eb8a53..e0811f8665 100644
--- a/routers/api/v1/packages/package.go
+++ b/routers/api/v1/packages/package.go
@@ -40,7 +40,7 @@ func ListPackages(ctx *context.APIContext) {
 	//   in: query
 	//   description: package type filter
 	//   type: string
-	//   enum: [cargo, chef, composer, conan, conda, container, debian, generic, helm, maven, npm, nuget, pub, pypi, rubygems, swift, vagrant]
+	//   enum: [cargo, chef, composer, conan, conda, container, debian, generic, helm, maven, npm, nuget, pub, pypi, rpm, rubygems, swift, vagrant]
 	// - name: q
 	//   in: query
 	//   description: name filter