Initial commit

2022-10-30 22:46:54 +01:00 · 2022-10-30 22:46:54 +01:00 · 4511c4c017
commit 4511c4c017
parent e6e5634d44
6 changed files with 1739 additions and 0 deletions
--- a/gitea.go
+++ b/gitea.go
@ -0,0 +1,93 @@
+package gitea
+
+import (
+	"errors"
+	"io"
+	"io/fs"
+	"net/http"
+	"strings"
+
+	"github.com/42wim/caddy-gitea/pkg/gitea"
+	"github.com/caddyserver/caddy/v2"
+	"github.com/caddyserver/caddy/v2/caddyconfig/caddyfile"
+	"github.com/caddyserver/caddy/v2/caddyconfig/httpcaddyfile"
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
+)
+
+func init() {
+	caddy.RegisterModule(Middleware{})
+	httpcaddyfile.RegisterHandlerDirective("gitea", parseCaddyfile)
+}
+
+func parseCaddyfile(h httpcaddyfile.Helper) (caddyhttp.MiddlewareHandler, error) {
+	var m Middleware
+	err := m.UnmarshalCaddyfile(h.Dispenser)
+	return m, err
+}
+
+// Middleware implements gitea plugin.
+type Middleware struct {
+	Client *gitea.Client `json:"-"`
+	Server string        `json:"server,omitempty"`
+	Token  string        `json:"token,omitempty"`
+}
+
+// CaddyModule returns the Caddy module information.
+func (Middleware) CaddyModule() caddy.ModuleInfo {
+	return caddy.ModuleInfo{
+		ID:  "http.handlers.gitea",
+		New: func() caddy.Module { return new(Middleware) },
+	}
+}
+
+// Provision provisions gitea client.
+func (m *Middleware) Provision(ctx caddy.Context) error {
+	m.Client = gitea.NewClient(m.Server, m.Token)
+
+	return nil
+}
+
+// Validate implements caddy.Validator.
+func (m *Middleware) Validate() error {
+	return nil
+}
+
+// UnmarshalCaddyfile unmarshals a Caddyfile.
+func (m *Middleware) UnmarshalCaddyfile(d *caddyfile.Dispenser) (err error) {
+	for d.Next() {
+		for n := d.Nesting(); d.NextBlock(n); {
+			switch d.Val() {
+			case "server":
+				d.Args(&m.Server)
+			case "token":
+				d.Args(&m.Token)
+			}
+		}
+	}
+
+	return nil
+}
+
+// ServeHTTP performs gitea content fetcher.
+func (m Middleware) ServeHTTP(w http.ResponseWriter, r *http.Request, _ caddyhttp.Handler) error {
+	h := strings.Split(r.Host, ".")
+	fp := h[0] + r.URL.Path
+
+	f, err := m.Client.Open(fp, r.URL.Query().Get("ref"))
+	if err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			return caddyhttp.Error(http.StatusNotFound, err)
+		}
+	}
+
+	_, err = io.Copy(w, f)
+	return err
+}
+
+// Interface guards
+var (
+	_ caddy.Provisioner           = (*Middleware)(nil)
+	_ caddy.Validator             = (*Middleware)(nil)
+	_ caddyhttp.MiddlewareHandler = (*Middleware)(nil)
+	_ caddyfile.Unmarshaler       = (*Middleware)(nil)
+)
--- a/go.mod
+++ b/go.mod
@ -0,0 +1,130 @@
+module github.com/42wim/caddy-gitea
+
+go 1.19
+
+require (
+	github.com/BurntSushi/toml v1.2.1
+	github.com/alecthomas/chroma v0.10.0
+	github.com/caddyserver/caddy/v2 v2.6.2
+	github.com/spf13/viper v1.13.0
+	github.com/yuin/goldmark v1.5.2
+	github.com/yuin/goldmark-highlighting v0.0.0-20220208100518-594be1970594
+	gopkg.in/yaml.v3 v3.0.1
+)
+
+require (
+	filippo.io/edwards25519 v1.0.0 // indirect
+	github.com/AndreasBriese/bbloom v0.0.0-20190825152654-46b345b51c96 // indirect
+	github.com/Masterminds/goutils v1.1.1 // indirect
+	github.com/Masterminds/semver/v3 v3.1.1 // indirect
+	github.com/Masterminds/sprig/v3 v3.2.2 // indirect
+	github.com/antlr/antlr4/runtime/Go/antlr v1.4.10 // indirect
+	github.com/aryann/difflib v0.0.0-20210328193216-ff5ff6dc229b // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/caddyserver/certmagic v0.17.2 // indirect
+	github.com/cespare/xxhash v1.1.0 // indirect
+	github.com/cespare/xxhash/v2 v2.1.2 // indirect
+	github.com/chzyer/readline v1.5.1 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/dgraph-io/badger v1.6.2 // indirect
+	github.com/dgraph-io/badger/v2 v2.2007.4 // indirect
+	github.com/dgraph-io/ristretto v0.1.1 // indirect
+	github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13 // indirect
+	github.com/dlclark/regexp2 v1.7.0 // indirect
+	github.com/dustin/go-humanize v1.0.1-0.20200219035652-afde56e7acac // indirect
+	github.com/fsnotify/fsnotify v1.6.0 // indirect
+	github.com/go-kit/kit v0.12.0 // indirect
+	github.com/go-kit/log v0.2.1 // indirect
+	github.com/go-logfmt/logfmt v0.5.1 // indirect
+	github.com/go-sql-driver/mysql v1.6.0 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 // indirect
+	github.com/golang/glog v1.0.0 // indirect
+	github.com/golang/mock v1.6.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/snappy v0.0.4 // indirect
+	github.com/google/cel-go v0.12.5 // indirect
+	github.com/google/pprof v0.0.0-20221010195024-131d412537ea // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/huandu/xstrings v1.3.2 // indirect
+	github.com/imdario/mergo v0.3.13 // indirect
+	github.com/inconshreveable/mousetrap v1.0.1 // indirect
+	github.com/jackc/chunkreader/v2 v2.0.1 // indirect
+	github.com/jackc/pgconn v1.13.0 // indirect
+	github.com/jackc/pgio v1.0.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgproto3/v2 v2.3.1 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20200714003250-2b9c44734f2b // indirect
+	github.com/jackc/pgtype v1.12.0 // indirect
+	github.com/jackc/pgx/v4 v4.17.2 // indirect
+	github.com/klauspost/compress v1.15.12 // indirect
+	github.com/klauspost/cpuid/v2 v2.1.2 // indirect
+	github.com/libdns/libdns v0.2.1 // indirect
+	github.com/lucas-clemente/quic-go v0.30.0 // indirect
+	github.com/magiconair/properties v1.8.6 // indirect
+	github.com/manifoldco/promptui v0.9.0 // indirect
+	github.com/marten-seemann/qpack v0.3.0 // indirect
+	github.com/marten-seemann/qtls-go1-18 v0.1.3 // indirect
+	github.com/marten-seemann/qtls-go1-19 v0.1.1 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.16 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/mgutz/ansi v0.0.0-20200706080929-d51e80ef957d // indirect
+	github.com/mholt/acmez v1.0.4 // indirect
+	github.com/micromdm/scep/v2 v2.1.0 // indirect
+	github.com/miekg/dns v1.1.50 // indirect
+	github.com/mitchellh/copystructure v1.2.0 // indirect
+	github.com/mitchellh/go-ps v1.0.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/onsi/ginkgo/v2 v2.4.0 // indirect
+	github.com/pelletier/go-toml v1.9.5 // indirect
+	github.com/pelletier/go-toml/v2 v2.0.5 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/prometheus/client_golang v1.13.0 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.37.0 // indirect
+	github.com/prometheus/procfs v0.8.0 // indirect
+	github.com/rs/xid v1.4.0 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/shopspring/decimal v1.3.1 // indirect
+	github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
+	github.com/sirupsen/logrus v1.9.0 // indirect
+	github.com/slackhq/nebula v1.6.1 // indirect
+	github.com/smallstep/certificates v0.22.1 // indirect
+	github.com/smallstep/cli v0.22.0 // indirect
+	github.com/smallstep/nosql v0.5.0 // indirect
+	github.com/smallstep/truststore v0.12.0 // indirect
+	github.com/spf13/afero v1.9.2 // indirect
+	github.com/spf13/cast v1.5.0 // indirect
+	github.com/spf13/cobra v1.6.1 // indirect
+	github.com/spf13/jwalterweatherman v1.1.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/stoewer/go-strcase v1.2.0 // indirect
+	github.com/subosito/gotenv v1.4.1 // indirect
+	github.com/tailscale/tscert v0.0.0-20220316030059-54bbcb9f74e2 // indirect
+	github.com/urfave/cli v1.22.10 // indirect
+	go.etcd.io/bbolt v1.3.6 // indirect
+	go.mozilla.org/pkcs7 v0.0.0-20210826202110-33d05740a352 // indirect
+	go.step.sm/cli-utils v0.7.5 // indirect
+	go.step.sm/crypto v0.22.0 // indirect
+	go.step.sm/linkedca v0.18.0 // indirect
+	go.uber.org/atomic v1.10.0 // indirect
+	go.uber.org/multierr v1.8.0 // indirect
+	go.uber.org/zap v1.23.0 // indirect
+	golang.org/x/crypto v0.1.0 // indirect
+	golang.org/x/exp v0.0.0-20221028150844-83b7d23a625f // indirect
+	golang.org/x/mod v0.6.0 // indirect
+	golang.org/x/net v0.1.0 // indirect
+	golang.org/x/sys v0.1.0 // indirect
+	golang.org/x/term v0.1.0 // indirect
+	golang.org/x/text v0.4.0 // indirect
+	golang.org/x/tools v0.2.0 // indirect
+	google.golang.org/genproto v0.0.0-20221018160656-63c7b68cfc55 // indirect
+	google.golang.org/grpc v1.50.1 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+	gopkg.in/ini.v1 v1.67.0 // indirect
+	gopkg.in/square/go-jose.v2 v2.6.0 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	howett.net/plist v1.0.0 // indirect
+)
--- a/go.sum
+++ b/go.sum
--- a/pkg/gitea/frontmatter.go
+++ b/pkg/gitea/frontmatter.go
@ -0,0 +1,181 @@
+// Taken from caddy source code (https://github.com/mholt/caddy/)
+// Copyright 2015 Matthew Holt and The Caddy Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//nolint:all
+package gitea
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"unicode"
+
+	"github.com/BurntSushi/toml"
+	"github.com/alecthomas/chroma/formatters/html"
+	"github.com/yuin/goldmark"
+	highlighting "github.com/yuin/goldmark-highlighting"
+	"github.com/yuin/goldmark/extension"
+	"github.com/yuin/goldmark/parser"
+	gmhtml "github.com/yuin/goldmark/renderer/html"
+	"gopkg.in/yaml.v3"
+)
+
+func extractFrontMatter(input string) (map[string]any, string, error) {
+	// get the bounds of the first non-empty line
+	var firstLineStart, firstLineEnd int
+	lineEmpty := true
+	for i, b := range input {
+		if b == '\n' {
+			firstLineStart = firstLineEnd
+			if firstLineStart > 0 {
+				firstLineStart++ // skip newline character
+			}
+			firstLineEnd = i
+			if !lineEmpty {
+				break
+			}
+			continue
+		}
+		lineEmpty = lineEmpty && unicode.IsSpace(b)
+	}
+	firstLine := input[firstLineStart:firstLineEnd]
+
+	// ensure residue windows carriage return byte is removed
+	firstLine = strings.TrimSpace(firstLine)
+
+	// see what kind of front matter there is, if any
+	var closingFence []string
+	var fmParser func([]byte) (map[string]any, error)
+	for _, fmType := range supportedFrontMatterTypes {
+		if firstLine == fmType.FenceOpen {
+			closingFence = fmType.FenceClose
+			fmParser = fmType.ParseFunc
+		}
+	}
+
+	if fmParser == nil {
+		// no recognized front matter; whole document is body
+		return nil, input, nil
+	}
+
+	// find end of front matter
+	var fmEndFence string
+	fmEndFenceStart := -1
+	for _, fence := range closingFence {
+		index := strings.Index(input[firstLineEnd:], "\n"+fence)
+		if index >= 0 {
+			fmEndFenceStart = index
+			fmEndFence = fence
+			break
+		}
+	}
+	if fmEndFenceStart < 0 {
+		return nil, "", fmt.Errorf("unterminated front matter")
+	}
+	fmEndFenceStart += firstLineEnd + 1 // add 1 to account for newline
+
+	// extract and parse front matter
+	frontMatter := input[firstLineEnd:fmEndFenceStart]
+	fm, err := fmParser([]byte(frontMatter))
+	if err != nil {
+		return nil, "", err
+	}
+
+	// the rest is the body
+	body := input[fmEndFenceStart+len(fmEndFence):]
+
+	return fm, body, nil
+}
+
+func yamlFrontMatter(input []byte) (map[string]any, error) {
+	m := make(map[string]any)
+	err := yaml.Unmarshal(input, &m)
+	return m, err
+}
+
+func tomlFrontMatter(input []byte) (map[string]any, error) {
+	m := make(map[string]any)
+	err := toml.Unmarshal(input, &m)
+	return m, err
+}
+
+func jsonFrontMatter(input []byte) (map[string]any, error) {
+	input = append([]byte{'{'}, input...)
+	input = append(input, '}')
+	m := make(map[string]any)
+	err := json.Unmarshal(input, &m)
+	return m, err
+}
+
+type parsedMarkdownDoc struct {
+	Meta map[string]any `json:"meta,omitempty"`
+	Body string         `json:"body,omitempty"`
+}
+
+type frontMatterType struct {
+	FenceOpen  string
+	FenceClose []string
+	ParseFunc  func(input []byte) (map[string]any, error)
+}
+
+var supportedFrontMatterTypes = []frontMatterType{
+	{
+		FenceOpen:  "---",
+		FenceClose: []string{"---", "..."},
+		ParseFunc:  yamlFrontMatter,
+	},
+	{
+		FenceOpen:  "+++",
+		FenceClose: []string{"+++"},
+		ParseFunc:  tomlFrontMatter,
+	},
+	{
+		FenceOpen:  "{",
+		FenceClose: []string{"}"},
+		ParseFunc:  jsonFrontMatter,
+	},
+}
+
+func markdown(input []byte) ([]byte, error) {
+	md := goldmark.New(
+		goldmark.WithExtensions(
+			extension.GFM,
+			extension.Footnote,
+			highlighting.NewHighlighting(
+				highlighting.WithFormatOptions(
+					html.WithClasses(true),
+				),
+			),
+		),
+		goldmark.WithParserOptions(
+			parser.WithAutoHeadingID(),
+		),
+		goldmark.WithRendererOptions(
+			gmhtml.WithUnsafe(), // TODO: this is not awesome, maybe should be configurable?
+		),
+	)
+
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+
+	defer bufPool.Put(buf)
+
+	if err := md.Convert(input, buf); err != nil {
+		return input, err
+	}
+
+	return buf.Bytes(), nil
+}
--- a/pkg/gitea/fs.go
+++ b/pkg/gitea/fs.go
@ -0,0 +1,93 @@
+package gitea
+
+import (
+	"io"
+	"io/fs"
+	"time"
+)
+
+type fileInfo struct {
+	size  int64
+	isdir bool
+	name  string
+}
+
+type openFile struct {
+	content []byte
+	offset  int64
+	name    string
+	isdir   bool
+}
+
+func (g fileInfo) Name() string {
+	return g.name
+}
+
+func (g fileInfo) Size() int64 {
+	return g.size
+}
+
+func (g fileInfo) Mode() fs.FileMode {
+	return 0o444
+}
+
+func (g fileInfo) ModTime() time.Time {
+	return time.Time{}
+}
+
+func (g fileInfo) Sys() any {
+	return nil
+}
+
+func (g fileInfo) IsDir() bool {
+	return g.isdir
+}
+
+var _ io.Seeker = (*openFile)(nil)
+
+func (o *openFile) Close() error {
+	return nil
+}
+
+func (o *openFile) Stat() (fs.FileInfo, error) {
+	return fileInfo{
+		size:  int64(len(o.content)),
+		isdir: o.isdir,
+		name:  o.name,
+	}, nil
+}
+
+func (o *openFile) Read(b []byte) (int, error) {
+	if o.offset >= int64(len(o.content)) {
+		return 0, io.EOF
+	}
+
+	if o.offset < 0 {
+		return 0, &fs.PathError{Op: "read", Path: o.name, Err: fs.ErrInvalid}
+	}
+
+	n := copy(b, o.content[o.offset:])
+
+	o.offset += int64(n)
+
+	return n, nil
+}
+
+func (o *openFile) Seek(offset int64, whence int) (int64, error) {
+	switch whence {
+	case 0:
+		offset += 0
+	case 1:
+		offset += o.offset
+	case 2:
+		offset += int64(len(o.content))
+	}
+
+	if offset < 0 || offset > int64(len(o.content)) {
+		return 0, &fs.PathError{Op: "seek", Path: o.name, Err: fs.ErrInvalid}
+	}
+
+	o.offset = offset
+
+	return offset, nil
+}
--- a/pkg/gitea/gitea.go
+++ b/pkg/gitea/gitea.go
@ -0,0 +1,238 @@
+package gitea
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+
+	"github.com/spf13/viper"
+)
+
+type Client struct {
+	serverURL string
+	token     string
+}
+
+type pagesConfig struct {
+}
+
+type topicsResponse struct {
+	Topics []string `json:"topics"`
+}
+
+func NewClient(serverURL, token string) *Client {
+	return &Client{
+		serverURL: serverURL,
+		token:     token,
+	}
+}
+
+func (c *Client) Open(name, ref string) (fs.File, error) {
+	if ref == "" {
+		ref = "gitea-pages"
+	}
+
+	owner, repo, filepath, err := splitName(name)
+	if err != nil {
+		return nil, err
+	}
+
+	if !c.allowsPages(owner, repo) {
+		return nil, fs.ErrNotExist
+	}
+
+	if err := c.readConfig(owner, repo); err != nil {
+		return nil, err
+	}
+
+	if !validRefs(ref) {
+		return nil, fs.ErrNotExist
+	}
+
+	res, err := c.getRawFileOrLFS(owner, repo, filepath, ref)
+	if err != nil {
+		return nil, err
+	}
+
+	if strings.HasSuffix(filepath, ".md") {
+		res, err = handleMD(res)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &openFile{
+		content: res,
+		name:    filepath,
+	}, nil
+}
+
+func (c *Client) getRawFileOrLFS(owner, repo, filepath, ref string) ([]byte, error) {
+	var (
+		giteaURL string
+		err      error
+	)
+
+	giteaURL, err = url.JoinPath(c.serverURL+"/api/v1/repos/", owner, repo, "media", filepath)
+	if err != nil {
+		return nil, err
+	}
+
+	giteaURL += "?ref=" + url.QueryEscape(ref)
+
+	req, err := http.NewRequest(http.MethodGet, giteaURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Add("Authorization", "token "+c.token)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	switch resp.StatusCode {
+	case http.StatusNotFound:
+		return nil, fs.ErrNotExist
+	case http.StatusOK:
+	default:
+		return nil, fmt.Errorf("unexpected status code '%d'", resp.StatusCode)
+	}
+
+	res, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+
+	return res, nil
+
+}
+
+var bufPool = sync.Pool{
+	New: func() any {
+		return new(bytes.Buffer)
+	},
+}
+
+func handleMD(res []byte) ([]byte, error) {
+	meta, resbody, err := extractFrontMatter(string(res))
+	if err != nil {
+		return nil, err
+	}
+
+	resmd, err := markdown([]byte(resbody))
+	if err != nil {
+		return nil, err
+	}
+
+	res = append([]byte("<!DOCTYPE html>\n<html>\n<body>\n<h1>"), []byte(meta["title"].(string))...)
+	res = append(res, []byte("</h1>")...)
+	res = append(res, resmd...)
+	res = append(res, []byte("</body></html>")...)
+
+	return res, nil
+}
+
+func (c *Client) repoTopics(owner, repo string) ([]string, error) {
+	var (
+		giteaURL string
+		err      error
+	)
+
+	giteaURL, err = url.JoinPath(c.serverURL+"/api/v1/repos/", owner, repo, "topics")
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest(http.MethodGet, giteaURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Add("Authorization", "token "+c.token)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+
+	t := topicsResponse{}
+	json.Unmarshal(res, &t)
+
+	return t.Topics, nil
+}
+
+func (c *Client) allowsPages(owner, repo string) bool {
+	topics, err := c.repoTopics(owner, repo)
+	if err != nil {
+		return false
+	}
+
+	for _, topic := range topics {
+		if topic == "gitea-pages" {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (c *Client) readConfig(owner, repo string) error {
+	cfg, err := c.getRawFileOrLFS(owner, repo, "gitea-pages.toml", "gitea-pages")
+	if err != nil && !errors.Is(err, fs.ErrNotExist) {
+		return err
+	}
+
+	viper.SetConfigType("toml")
+	viper.ReadConfig(bytes.NewBuffer(cfg))
+
+	return nil
+}
+
+func splitName(name string) (string, string, string, error) {
+	parts := strings.Split(name, "/")
+
+	// parts contains: ["owner", "repo", "filepath"]
+	// return invalid path if not enough parts
+	if len(parts) < 3 {
+		return "", "", "", fs.ErrInvalid
+	}
+
+	owner := parts[0]
+	repo := parts[1]
+	filepath := strings.Join(parts[2:], "/")
+
+	return owner, repo, filepath, nil
+}
+
+func validRefs(ref string) bool {
+	validrefs := viper.GetStringSlice("allowedrefs")
+	for _, r := range validrefs {
+		if r == ref {
+			return true
+		}
+
+		if r == "*" {
+			return true
+		}
+	}
+
+	return false
+}