Add support for Pub packages (#20560)

* Added support for Pub packages.

* Update docs/content/doc/packages/overview.en-us.md

Co-authored-by: Gergely Nagy <algernon@users.noreply.github.com>

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Gergely Nagy <algernon@users.noreply.github.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

4 files changed, 292 insertions, 2 deletions

diff --git a/routers/api/packages/api.go b/routers/api/packages/api.go
index bb9a42e33d..4b274860dc 100644
--- a/routers/api/packages/api.go
+++ b/routers/api/packages/api.go
@@ -21,6 +21,7 @@ import (
 	"code.gitea.io/gitea/routers/api/packages/maven"
 	"code.gitea.io/gitea/routers/api/packages/npm"
 	"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/rubygems"
 	"code.gitea.io/gitea/services/auth"
@@ -216,6 +217,20 @@ func Routes() *web.Route {
 				}, reqPackageAccess(perm.AccessModeWrite))
 			})
 		})
+		r.Group("/pub", func() {
+			r.Group("/api/packages", func() {
+				r.Group("/versions/new", func() {
+					r.Get("", pub.RequestUpload)
+					r.Post("/upload", pub.UploadPackageFile)
+					r.Get("/finalize/{id}/{version}", pub.FinalizePackage)
+				}, reqPackageAccess(perm.AccessModeWrite))
+				r.Group("/{id}", func() {
+					r.Get("", pub.EnumeratePackageVersions)
+					r.Get("/files/{version}", pub.DownloadPackageFile)
+					r.Get("/{version}", pub.PackageVersionMetadata)
+				})
+			})
+		})
 		r.Group("/pypi", func() {
 			r.Post("/", reqPackageAccess(perm.AccessModeWrite), pypi.UploadPackageFile)
 			r.Get("/files/{id}/{version}/{filename}", pypi.DownloadPackageFile)
diff --git a/routers/api/packages/nuget/nuget.go b/routers/api/packages/nuget/nuget.go
index 4d630708b9..81ea28bcad 100644
--- a/routers/api/packages/nuget/nuget.go
+++ b/routers/api/packages/nuget/nuget.go
@@ -102,7 +102,7 @@ func RegistrationLeaf(ctx *context.Context) {
 	packageName := ctx.Params("id")
 	packageVersion := strings.TrimSuffix(ctx.Params("version"), ".json")
 
-	pv, err := packages_model.GetVersionByNameAndVersion(db.DefaultContext, ctx.Package.Owner.ID, packages_model.TypeNuGet, packageName, packageVersion)
+	pv, err := packages_model.GetVersionByNameAndVersion(ctx, ctx.Package.Owner.ID, packages_model.TypeNuGet, packageName, packageVersion)
 	if err != nil {
 		if err == packages_model.ErrPackageNotExist {
 			apiError(ctx, http.StatusNotFound, err)
diff --git a/routers/api/packages/pub/pub.go b/routers/api/packages/pub/pub.go
new file mode 100644
index 0000000000..470f446238
--- /dev/null
+++ b/routers/api/packages/pub/pub.go
@@ -0,0 +1,275 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package pub
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"sort"
+	"strings"
+	"time"
+
+	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/log"
+	packages_module "code.gitea.io/gitea/modules/packages"
+	pub_module "code.gitea.io/gitea/modules/packages/pub"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/routers/api/packages/helper"
+	packages_service "code.gitea.io/gitea/services/packages"
+)
+
+func jsonResponse(ctx *context.Context, status int, obj interface{}) {
+	resp := ctx.Resp
+	resp.Header().Set("Content-Type", "application/vnd.pub.v2+json")
+	resp.WriteHeader(status)
+	if err := json.NewEncoder(resp).Encode(obj); err != nil {
+		log.Error("JSON encode: %v", err)
+	}
+}
+
+func apiError(ctx *context.Context, status int, obj interface{}) {
+	type Error struct {
+		Code    string `json:"code"`
+		Message string `json:"message"`
+	}
+	type ErrorWrapper struct {
+		Error Error `json:"error"`
+	}
+
+	helper.LogAndProcessError(ctx, status, obj, func(message string) {
+		jsonResponse(ctx, status, ErrorWrapper{
+			Error: Error{
+				Code:    http.StatusText(status),
+				Message: message,
+			},
+		})
+	})
+}
+
+type packageVersions struct {
+	Name     string             `json:"name"`
+	Latest   *versionMetadata   `json:"latest"`
+	Versions []*versionMetadata `json:"versions"`
+}
+
+type versionMetadata struct {
+	Version    string      `json:"version"`
+	ArchiveURL string      `json:"archive_url"`
+	Published  time.Time   `json:"published"`
+	Pubspec    interface{} `json:"pubspec,omitempty"`
+}
+
+func packageDescriptorToMetadata(baseURL string, pd *packages_model.PackageDescriptor) *versionMetadata {
+	return &versionMetadata{
+		Version:    pd.Version.Version,
+		ArchiveURL: fmt.Sprintf("%s/files/%s.tar.gz", baseURL, url.PathEscape(pd.Version.Version)),
+		Published:  time.Unix(int64(pd.Version.CreatedUnix), 0),
+		Pubspec:    pd.Metadata.(*pub_module.Metadata).Pubspec,
+	}
+}
+
+func baseURL(ctx *context.Context) string {
+	return setting.AppURL + "api/packages/" + ctx.Package.Owner.Name + "/pub/api/packages"
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#list-all-versions-of-a-package
+func EnumeratePackageVersions(ctx *context.Context) {
+	packageName := ctx.Params("id")
+
+	pvs, err := packages_model.GetVersionsByPackageName(ctx, ctx.Package.Owner.ID, packages_model.TypePub, packageName)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+	if len(pvs) == 0 {
+		apiError(ctx, http.StatusNotFound, err)
+		return
+	}
+
+	pds, err := packages_model.GetPackageDescriptors(ctx, pvs)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	sort.Slice(pds, func(i, j int) bool {
+		return pds[i].SemVer.LessThan(pds[j].SemVer)
+	})
+
+	baseURL := fmt.Sprintf("%s/%s", baseURL(ctx), url.PathEscape(pds[0].Package.Name))
+
+	versions := make([]*versionMetadata, 0, len(pds))
+	for _, pd := range pds {
+		versions = append(versions, packageDescriptorToMetadata(baseURL, pd))
+	}
+
+	jsonResponse(ctx, http.StatusOK, &packageVersions{
+		Name:     pds[0].Package.Name,
+		Latest:   packageDescriptorToMetadata(baseURL, pds[0]),
+		Versions: versions,
+	})
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#deprecated-inspect-a-specific-version-of-a-package
+func PackageVersionMetadata(ctx *context.Context) {
+	packageName := ctx.Params("id")
+	packageVersion := ctx.Params("version")
+
+	pv, err := packages_model.GetVersionByNameAndVersion(ctx, ctx.Package.Owner.ID, packages_model.TypePub, packageName, packageVersion)
+	if err != nil {
+		if err == packages_model.ErrPackageNotExist {
+			apiError(ctx, http.StatusNotFound, err)
+			return
+		}
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	pd, err := packages_model.GetPackageDescriptor(ctx, pv)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	jsonResponse(ctx, http.StatusOK, packageDescriptorToMetadata(
+		fmt.Sprintf("%s/%s", baseURL(ctx), url.PathEscape(pd.Package.Name)),
+		pd,
+	))
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#publishing-packages
+func RequestUpload(ctx *context.Context) {
+	type UploadRequest struct {
+		URL    string            `json:"url"`
+		Fields map[string]string `json:"fields"`
+	}
+
+	jsonResponse(ctx, http.StatusOK, UploadRequest{
+		URL:    baseURL(ctx) + "/versions/new/upload",
+		Fields: make(map[string]string),
+	})
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#publishing-packages
+func UploadPackageFile(ctx *context.Context) {
+	file, _, err := ctx.Req.FormFile("file")
+	if err != nil {
+		apiError(ctx, http.StatusBadRequest, err)
+		return
+	}
+	defer file.Close()
+
+	buf, err := packages_module.CreateHashedBufferFromReader(file, 32*1024*1024)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+	defer buf.Close()
+
+	pck, err := pub_module.ParsePackage(buf)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	if _, err := buf.Seek(0, io.SeekStart); err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	_, _, err = packages_service.CreatePackageAndAddFile(
+		&packages_service.PackageCreationInfo{
+			PackageInfo: packages_service.PackageInfo{
+				Owner:       ctx.Package.Owner,
+				PackageType: packages_model.TypePub,
+				Name:        pck.Name,
+				Version:     pck.Version,
+			},
+			SemverCompatible: true,
+			Creator:          ctx.Doer,
+			Metadata:         pck.Metadata,
+		},
+		&packages_service.PackageFileCreationInfo{
+			PackageFileInfo: packages_service.PackageFileInfo{
+				Filename: strings.ToLower(pck.Version + ".tar.gz"),
+			},
+			Data:   buf,
+			IsLead: true,
+		},
+	)
+	if err != nil {
+		if err == packages_model.ErrDuplicatePackageVersion {
+			apiError(ctx, http.StatusBadRequest, err)
+			return
+		}
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	ctx.Resp.Header().Set("Location", fmt.Sprintf("%s/versions/new/finalize/%s/%s", baseURL(ctx), url.PathEscape(pck.Name), url.PathEscape(pck.Version)))
+	ctx.Status(http.StatusNoContent)
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#publishing-packages
+func FinalizePackage(ctx *context.Context) {
+	packageName := ctx.Params("id")
+	packageVersion := ctx.Params("version")
+
+	_, err := packages_model.GetVersionByNameAndVersion(ctx, ctx.Package.Owner.ID, packages_model.TypePub, packageName, packageVersion)
+	if err != nil {
+		if err == packages_model.ErrPackageNotExist {
+			apiError(ctx, http.StatusNotFound, err)
+			return
+		}
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	type Success struct {
+		Message string `json:"message"`
+	}
+	type SuccessWrapper struct {
+		Success Success `json:"success"`
+	}
+
+	jsonResponse(ctx, http.StatusOK, SuccessWrapper{Success{}})
+}
+
+// https://github.com/dart-lang/pub/blob/master/doc/repository-spec-v2.md#deprecated-download-a-specific-version-of-a-package
+func DownloadPackageFile(ctx *context.Context) {
+	packageName := ctx.Params("id")
+	packageVersion := strings.TrimSuffix(ctx.Params("version"), ".tar.gz")
+
+	pv, err := packages_model.GetVersionByNameAndVersion(ctx, ctx.Package.Owner.ID, packages_model.TypePub, packageName, packageVersion)
+	if err != nil {
+		if err == packages_model.ErrPackageNotExist {
+			apiError(ctx, http.StatusNotFound, err)
+			return
+		}
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	pd, err := packages_model.GetPackageDescriptor(ctx, pv)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+
+	pf := pd.Files[0].File
+
+	s, _, err := packages_service.GetPackageFileStream(ctx, pf)
+	if err != nil {
+		apiError(ctx, http.StatusInternalServerError, err)
+		return
+	}
+	defer s.Close()
+
+	ctx.ServeStream(s, pf.Name)
+}
diff --git a/routers/api/v1/packages/package.go b/routers/api/v1/packages/package.go
index 5a9c93b3ca..2c02389102 100644
--- a/routers/api/v1/packages/package.go
+++ b/routers/api/v1/packages/package.go
@@ -41,7 +41,7 @@ func ListPackages(ctx *context.APIContext) {
 	//   in: query
 	//   description: package type filter
 	//   type: string
-	//   enum: [composer, conan, container, generic, helm, maven, npm, nuget, pypi, rubygems]
+	//   enum: [composer, conan, container, generic, helm, maven, npm, nuget, pub, pypi, rubygems]
 	// - name: q
 	//   in: query
 	//   description: name filter