Add Helm Chart registry (#19406)

modules/packages/helm/metadata.go

@@ -0,0 +1,131 @@
+// 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 helm
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"errors"
+	"io"
+	"strings"
+
+	"code.gitea.io/gitea/modules/validation"
+
+	"github.com/hashicorp/go-version"
+	"gopkg.in/yaml.v2"
+)
+
+var (
+	// ErrMissingChartFile indicates a missing Chart.yaml file
+	ErrMissingChartFile = errors.New("Chart.yaml file is missing")
+	// ErrInvalidName indicates an invalid package name
+	ErrInvalidName = errors.New("package name is invalid")
+	// ErrInvalidVersion indicates an invalid package version
+	ErrInvalidVersion = errors.New("package version is invalid")
+	// ErrInvalidChart indicates an invalid chart
+	ErrInvalidChart = errors.New("chart is invalid")
+)
+
+// Metadata for a Chart file. This models the structure of a Chart.yaml file.
+type Metadata struct {
+	APIVersion   string            `json:"api_version" yaml:"apiVersion"`
+	Type         string            `json:"type,omitempty" yaml:"type,omitempty"`
+	Name         string            `json:"name" yaml:"name"`
+	Version      string            `json:"version" yaml:"version"`
+	AppVersion   string            `json:"app_version,omitempty" yaml:"appVersion,omitempty"`
+	Home         string            `json:"home,omitempty" yaml:"home,omitempty"`
+	Sources      []string          `json:"sources,omitempty" yaml:"sources,omitempty"`
+	Description  string            `json:"description,omitempty" yaml:"description,omitempty"`
+	Keywords     []string          `json:"keywords,omitempty" yaml:"keywords,omitempty"`
+	Maintainers  []*Maintainer     `json:"maintainers,omitempty" yaml:"maintainers,omitempty"`
+	Icon         string            `json:"icon,omitempty" yaml:"icon,omitempty"`
+	Condition    string            `json:"condition,omitempty" yaml:"condition,omitempty"`
+	Tags         string            `json:"tags,omitempty" yaml:"tags,omitempty"`
+	Deprecated   bool              `json:"deprecated,omitempty" yaml:"deprecated,omitempty"`
+	Annotations  map[string]string `json:"annotations,omitempty" yaml:"annotations,omitempty"`
+	KubeVersion  string            `json:"kube_version,omitempty" yaml:"kubeVersion,omitempty"`
+	Dependencies []*Dependency     `json:"dependencies,omitempty" yaml:"dependencies,omitempty"`
+}
+
+type Maintainer struct {
+	Name  string `json:"name,omitempty" yaml:"name,omitempty"`
+	Email string `json:"email,omitempty" yaml:"email,omitempty"`
+	URL   string `json:"url,omitempty" yaml:"url,omitempty"`
+}
+
+type Dependency struct {
+	Name         string        `json:"name" yaml:"name"`
+	Version      string        `json:"version,omitempty" yaml:"version,omitempty"`
+	Repository   string        `json:"repository" yaml:"repository"`
+	Condition    string        `json:"condition,omitempty" yaml:"condition,omitempty"`
+	Tags         []string      `json:"tags,omitempty" yaml:"tags,omitempty"`
+	Enabled      bool          `json:"enabled,omitempty" yaml:"enabled,omitempty"`
+	ImportValues []interface{} `json:"import_values,omitempty" yaml:"import-values,omitempty"`
+	Alias        string        `json:"alias,omitempty" yaml:"alias,omitempty"`
+}
+
+// ParseChartArchive parses the metadata of a Helm archive
+func ParseChartArchive(r io.Reader) (*Metadata, error) {
+	gzr, err := gzip.NewReader(r)
+	if err != nil {
+		return nil, err
+	}
+	defer gzr.Close()
+
+	tr := tar.NewReader(gzr)
+	for {
+		hd, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		if hd.Typeflag != tar.TypeReg {
+			continue
+		}
+
+		if hd.FileInfo().Name() == "Chart.yaml" {
+			if strings.Count(hd.Name, "/") != 1 {
+				continue
+			}
+
+			return ParseChartFile(tr)
+		}
+	}
+
+	return nil, ErrMissingChartFile
+}
+
+// ParseChartFile parses a Chart.yaml file to retrieve the metadata of a Helm chart
+func ParseChartFile(r io.Reader) (*Metadata, error) {
+	var metadata *Metadata
+	if err := yaml.NewDecoder(r).Decode(&metadata); err != nil {
+		return nil, err
+	}
+
+	if metadata.APIVersion == "" {
+		return nil, ErrInvalidChart
+	}
+
+	if metadata.Type != "" && metadata.Type != "application" && metadata.Type != "library" {
+		return nil, ErrInvalidChart
+	}
+
+	if metadata.Name == "" {
+		return nil, ErrInvalidName
+	}
+
+	if _, err := version.NewSemver(metadata.Version); err != nil {
+		return nil, ErrInvalidVersion
+	}
+
+	if !validation.IsValidURL(metadata.Home) {
+		metadata.Home = ""
+	}
+
+	return metadata, nil
+}