Add Cargo package registry (#21888)

This PR implements a [Cargo registry](https://doc.rust-lang.org/cargo/)
to manage Rust packages. This package type was a little bit more
complicated because Cargo needs an additional Git repository to store
its package index.

Screenshots:

![grafik](https://user-images.githubusercontent.com/1666336/203102004-08d812ac-c066-4969-9bda-2fed818554eb.png)

![grafik](https://user-images.githubusercontent.com/1666336/203102141-d9970f14-dca6-4174-b17a-50ba1bd79087.png)

![grafik](https://user-images.githubusercontent.com/1666336/203102244-dc05743b-78b6-4d97-998e-ef76341a978f.png)

---------

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

4 files changed, 258 insertions, 0 deletions

diff --git a/modules/packages/cargo/parser.go b/modules/packages/cargo/parser.go
new file mode 100644
index 0000000000..36cd44df84
--- /dev/null
+++ b/modules/packages/cargo/parser.go
@@ -0,0 +1,169 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cargo
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+	"regexp"
+
+	"code.gitea.io/gitea/modules/json"
+	"code.gitea.io/gitea/modules/validation"
+
+	"github.com/hashicorp/go-version"
+)
+
+const PropertyYanked = "cargo.yanked"
+
+var (
+	ErrInvalidName    = errors.New("package name is invalid")
+	ErrInvalidVersion = errors.New("package version is invalid")
+)
+
+// Package represents a Cargo package
+type Package struct {
+	Name        string
+	Version     string
+	Metadata    *Metadata
+	Content     io.Reader
+	ContentSize int64
+}
+
+// Metadata represents the metadata of a Cargo package
+type Metadata struct {
+	Dependencies     []*Dependency       `json:"dependencies,omitempty"`
+	Features         map[string][]string `json:"features,omitempty"`
+	Authors          []string            `json:"authors,omitempty"`
+	Description      string              `json:"description,omitempty"`
+	DocumentationURL string              `json:"documentation_url,omitempty"`
+	ProjectURL       string              `json:"project_url,omitempty"`
+	Readme           string              `json:"readme,omitempty"`
+	Keywords         []string            `json:"keywords,omitempty"`
+	Categories       []string            `json:"categories,omitempty"`
+	License          string              `json:"license,omitempty"`
+	RepositoryURL    string              `json:"repository_url,omitempty"`
+	Links            string              `json:"links,omitempty"`
+}
+
+type Dependency struct {
+	Name            string   `json:"name"`
+	Req             string   `json:"req"`
+	Features        []string `json:"features"`
+	Optional        bool     `json:"optional"`
+	DefaultFeatures bool     `json:"default_features"`
+	Target          *string  `json:"target"`
+	Kind            string   `json:"kind"`
+	Registry        *string  `json:"registry"`
+	Package         *string  `json:"package"`
+}
+
+var nameMatch = regexp.MustCompile(`\A[a-zA-Z][a-zA-Z0-9-_]{0,63}\z`)
+
+// ParsePackage reads the metadata and content of a package
+func ParsePackage(r io.Reader) (*Package, error) {
+	var size uint32
+	if err := binary.Read(r, binary.LittleEndian, &size); err != nil {
+		return nil, err
+	}
+
+	p, err := parsePackage(io.LimitReader(r, int64(size)))
+	if err != nil {
+		return nil, err
+	}
+
+	if err := binary.Read(r, binary.LittleEndian, &size); err != nil {
+		return nil, err
+	}
+
+	p.Content = io.LimitReader(r, int64(size))
+	p.ContentSize = int64(size)
+
+	return p, nil
+}
+
+func parsePackage(r io.Reader) (*Package, error) {
+	var meta struct {
+		Name string `json:"name"`
+		Vers string `json:"vers"`
+		Deps []struct {
+			Name               string   `json:"name"`
+			VersionReq         string   `json:"version_req"`
+			Features           []string `json:"features"`
+			Optional           bool     `json:"optional"`
+			DefaultFeatures    bool     `json:"default_features"`
+			Target             *string  `json:"target"`
+			Kind               string   `json:"kind"`
+			Registry           *string  `json:"registry"`
+			ExplicitNameInToml string   `json:"explicit_name_in_toml"`
+		} `json:"deps"`
+		Features      map[string][]string `json:"features"`
+		Authors       []string            `json:"authors"`
+		Description   string              `json:"description"`
+		Documentation string              `json:"documentation"`
+		Homepage      string              `json:"homepage"`
+		Readme        string              `json:"readme"`
+		ReadmeFile    string              `json:"readme_file"`
+		Keywords      []string            `json:"keywords"`
+		Categories    []string            `json:"categories"`
+		License       string              `json:"license"`
+		LicenseFile   string              `json:"license_file"`
+		Repository    string              `json:"repository"`
+		Links         string              `json:"links"`
+	}
+	if err := json.NewDecoder(r).Decode(&meta); err != nil {
+		return nil, err
+	}
+
+	if !nameMatch.MatchString(meta.Name) {
+		return nil, ErrInvalidName
+	}
+
+	if _, err := version.NewSemver(meta.Vers); err != nil {
+		return nil, ErrInvalidVersion
+	}
+
+	if !validation.IsValidURL(meta.Homepage) {
+		meta.Homepage = ""
+	}
+	if !validation.IsValidURL(meta.Documentation) {
+		meta.Documentation = ""
+	}
+	if !validation.IsValidURL(meta.Repository) {
+		meta.Repository = ""
+	}
+
+	dependencies := make([]*Dependency, 0, len(meta.Deps))
+	for _, dep := range meta.Deps {
+		dependencies = append(dependencies, &Dependency{
+			Name:            dep.Name,
+			Req:             dep.VersionReq,
+			Features:        dep.Features,
+			Optional:        dep.Optional,
+			DefaultFeatures: dep.DefaultFeatures,
+			Target:          dep.Target,
+			Kind:            dep.Kind,
+			Registry:        dep.Registry,
+		})
+	}
+
+	return &Package{
+		Name:    meta.Name,
+		Version: meta.Vers,
+		Metadata: &Metadata{
+			Dependencies:     dependencies,
+			Features:         meta.Features,
+			Authors:          meta.Authors,
+			Description:      meta.Description,
+			DocumentationURL: meta.Documentation,
+			ProjectURL:       meta.Homepage,
+			Readme:           meta.Readme,
+			Keywords:         meta.Keywords,
+			Categories:       meta.Categories,
+			License:          meta.License,
+			RepositoryURL:    meta.Repository,
+			Links:            meta.Links,
+		},
+	}, nil
+}
diff --git a/modules/packages/cargo/parser_test.go b/modules/packages/cargo/parser_test.go
new file mode 100644
index 0000000000..2230a5b499
--- /dev/null
+++ b/modules/packages/cargo/parser_test.go
@@ -0,0 +1,86 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cargo
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	description = "Package Description"
+	author      = "KN4CK3R"
+	homepage    = "https://gitea.io/"
+	license     = "MIT"
+)
+
+func TestParsePackage(t *testing.T) {
+	createPackage := func(name, version string) io.Reader {
+		metadata := `{
+   "name":"` + name + `",
+   "vers":"` + version + `",
+   "description":"` + description + `",
+   "authors": ["` + author + `"],
+   "deps":[
+      {
+         "name":"dep",
+         "version_req":"1.0"
+      }
+   ],
+   "homepage":"` + homepage + `",
+   "license":"` + license + `"
+}`
+
+		var buf bytes.Buffer
+		binary.Write(&buf, binary.LittleEndian, uint32(len(metadata)))
+		buf.WriteString(metadata)
+		binary.Write(&buf, binary.LittleEndian, uint32(4))
+		buf.WriteString("test")
+		return &buf
+	}
+
+	t.Run("InvalidName", func(t *testing.T) {
+		for _, name := range []string{"", "0test", "-test", "_test", strings.Repeat("a", 65)} {
+			data := createPackage(name, "1.0.0")
+
+			cp, err := ParsePackage(data)
+			assert.Nil(t, cp)
+			assert.ErrorIs(t, err, ErrInvalidName)
+		}
+	})
+
+	t.Run("InvalidVersion", func(t *testing.T) {
+		for _, version := range []string{"", "1.", "-1.0", "1.0.0/1"} {
+			data := createPackage("test", version)
+
+			cp, err := ParsePackage(data)
+			assert.Nil(t, cp)
+			assert.ErrorIs(t, err, ErrInvalidVersion)
+		}
+	})
+
+	t.Run("Valid", func(t *testing.T) {
+		data := createPackage("test", "1.0.0")
+
+		cp, err := ParsePackage(data)
+		assert.NotNil(t, cp)
+		assert.NoError(t, err)
+
+		assert.Equal(t, "test", cp.Name)
+		assert.Equal(t, "1.0.0", cp.Version)
+		assert.Equal(t, description, cp.Metadata.Description)
+		assert.Equal(t, []string{author}, cp.Metadata.Authors)
+		assert.Len(t, cp.Metadata.Dependencies, 1)
+		assert.Equal(t, "dep", cp.Metadata.Dependencies[0].Name)
+		assert.Equal(t, homepage, cp.Metadata.ProjectURL)
+		assert.Equal(t, license, cp.Metadata.License)
+		content, _ := io.ReadAll(cp.Content)
+		assert.Equal(t, "test", string(content))
+	})
+}
diff --git a/modules/repository/create.go b/modules/repository/create.go
index 7bcda0fe45..b9a72ad573 100644
--- a/modules/repository/create.go
+++ b/modules/repository/create.go
@@ -211,6 +211,7 @@ func CreateRepository(doer, u *user_model.User, opts CreateRepoOptions) (*repo_m
 		IsEmpty:                         !opts.AutoInit,
 		TrustModel:                      opts.TrustModel,
 		IsMirror:                        opts.IsMirror,
+		DefaultBranch:                   opts.DefaultBranch,
 	}
 
 	var rollbackRepo *repo_model.Repository
diff --git a/modules/setting/packages.go b/modules/setting/packages.go
index d0cd80aa03..190c17dd8f 100644
--- a/modules/setting/packages.go
+++ b/modules/setting/packages.go
@@ -25,6 +25,7 @@ var (
 
 		LimitTotalOwnerCount int64
 		LimitTotalOwnerSize  int64
+		LimitSizeCargo       int64
 		LimitSizeComposer    int64
 		LimitSizeConan       int64
 		LimitSizeConda       int64
@@ -65,6 +66,7 @@ func newPackages() {
 	}
 
 	Packages.LimitTotalOwnerSize = mustBytes(sec, "LIMIT_TOTAL_OWNER_SIZE")
+	Packages.LimitSizeCargo = mustBytes(sec, "LIMIT_SIZE_CARGO")
 	Packages.LimitSizeComposer = mustBytes(sec, "LIMIT_SIZE_COMPOSER")
 	Packages.LimitSizeConan = mustBytes(sec, "LIMIT_SIZE_CONAN")
 	Packages.LimitSizeConda = mustBytes(sec, "LIMIT_SIZE_CONDA")