recover from panics such as out-of-bounds array access & nil pointer access, print a stack trace and return 5xx error instead of the service crashing and relying on Execution framework to handle crashes
276 lines
5.9 KiB
Go
276 lines
5.9 KiB
Go
package middleware
|
|
|
|
import (
|
|
"fmt"
|
|
"html/template"
|
|
"net/http"
|
|
"net/url"
|
|
"os"
|
|
"path"
|
|
"path/filepath"
|
|
"strings"
|
|
|
|
"github.com/labstack/echo/v4"
|
|
"github.com/labstack/gommon/bytes"
|
|
)
|
|
|
|
type (
|
|
// StaticConfig defines the config for Static middleware.
|
|
StaticConfig struct {
|
|
// Skipper defines a function to skip middleware.
|
|
Skipper Skipper
|
|
|
|
// Root directory from where the static content is served.
|
|
// Required.
|
|
Root string `yaml:"root"`
|
|
|
|
// Index file for serving a directory.
|
|
// Optional. Default value "index.html".
|
|
Index string `yaml:"index"`
|
|
|
|
// Enable HTML5 mode by forwarding all not-found requests to root so that
|
|
// SPA (single-page application) can handle the routing.
|
|
// Optional. Default value false.
|
|
HTML5 bool `yaml:"html5"`
|
|
|
|
// Enable directory browsing.
|
|
// Optional. Default value false.
|
|
Browse bool `yaml:"browse"`
|
|
|
|
// Enable ignoring of the base of the URL path.
|
|
// Example: when assigning a static middleware to a non root path group,
|
|
// the filesystem path is not doubled
|
|
// Optional. Default value false.
|
|
IgnoreBase bool `yaml:"ignoreBase"`
|
|
|
|
// Filesystem provides access to the static content.
|
|
// Optional. Defaults to http.Dir(config.Root)
|
|
Filesystem http.FileSystem `yaml:"-"`
|
|
}
|
|
)
|
|
|
|
const html = `
|
|
<!DOCTYPE html>
|
|
<html lang="en">
|
|
<head>
|
|
<meta charset="UTF-8">
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|
<meta http-equiv="X-UA-Compatible" content="ie=edge">
|
|
<title>{{ .Name }}</title>
|
|
<style>
|
|
body {
|
|
font-family: Menlo, Consolas, monospace;
|
|
padding: 48px;
|
|
}
|
|
header {
|
|
padding: 4px 16px;
|
|
font-size: 24px;
|
|
}
|
|
ul {
|
|
list-style-type: none;
|
|
margin: 0;
|
|
padding: 20px 0 0 0;
|
|
display: flex;
|
|
flex-wrap: wrap;
|
|
}
|
|
li {
|
|
width: 300px;
|
|
padding: 16px;
|
|
}
|
|
li a {
|
|
display: block;
|
|
overflow: hidden;
|
|
white-space: nowrap;
|
|
text-overflow: ellipsis;
|
|
text-decoration: none;
|
|
transition: opacity 0.25s;
|
|
}
|
|
li span {
|
|
color: #707070;
|
|
font-size: 12px;
|
|
}
|
|
li a:hover {
|
|
opacity: 0.50;
|
|
}
|
|
.dir {
|
|
color: #E91E63;
|
|
}
|
|
.file {
|
|
color: #673AB7;
|
|
}
|
|
</style>
|
|
</head>
|
|
<body>
|
|
<header>
|
|
{{ .Name }}
|
|
</header>
|
|
<ul>
|
|
{{ range .Files }}
|
|
<li>
|
|
{{ if .Dir }}
|
|
{{ $name := print .Name "/" }}
|
|
<a class="dir" href="{{ $name }}">{{ $name }}</a>
|
|
{{ else }}
|
|
<a class="file" href="{{ .Name }}">{{ .Name }}</a>
|
|
<span>{{ .Size }}</span>
|
|
{{ end }}
|
|
</li>
|
|
{{ end }}
|
|
</ul>
|
|
</body>
|
|
</html>
|
|
`
|
|
|
|
var (
|
|
// DefaultStaticConfig is the default Static middleware config.
|
|
DefaultStaticConfig = StaticConfig{
|
|
Skipper: DefaultSkipper,
|
|
Index: "index.html",
|
|
}
|
|
)
|
|
|
|
// Static returns a Static middleware to serves static content from the provided
|
|
// root directory.
|
|
func Static(root string) echo.MiddlewareFunc {
|
|
c := DefaultStaticConfig
|
|
c.Root = root
|
|
return StaticWithConfig(c)
|
|
}
|
|
|
|
// StaticWithConfig returns a Static middleware with config.
|
|
// See `Static()`.
|
|
func StaticWithConfig(config StaticConfig) echo.MiddlewareFunc {
|
|
// Defaults
|
|
if config.Root == "" {
|
|
config.Root = "." // For security we want to restrict to CWD.
|
|
}
|
|
if config.Skipper == nil {
|
|
config.Skipper = DefaultStaticConfig.Skipper
|
|
}
|
|
if config.Index == "" {
|
|
config.Index = DefaultStaticConfig.Index
|
|
}
|
|
if config.Filesystem == nil {
|
|
config.Filesystem = http.Dir(config.Root)
|
|
config.Root = "."
|
|
}
|
|
|
|
// Index template
|
|
t, err := template.New("index").Parse(html)
|
|
if err != nil {
|
|
panic(fmt.Sprintf("echo: %v", err))
|
|
}
|
|
|
|
return func(next echo.HandlerFunc) echo.HandlerFunc {
|
|
return func(c echo.Context) (err error) {
|
|
if config.Skipper(c) {
|
|
return next(c)
|
|
}
|
|
|
|
p := c.Request().URL.Path
|
|
if strings.HasSuffix(c.Path(), "*") { // When serving from a group, e.g. `/static*`.
|
|
p = c.Param("*")
|
|
}
|
|
p, err = url.PathUnescape(p)
|
|
if err != nil {
|
|
return
|
|
}
|
|
name := filepath.Join(config.Root, filepath.Clean("/"+p)) // "/"+ for security
|
|
|
|
if config.IgnoreBase {
|
|
routePath := path.Base(strings.TrimRight(c.Path(), "/*"))
|
|
baseURLPath := path.Base(p)
|
|
if baseURLPath == routePath {
|
|
i := strings.LastIndex(name, routePath)
|
|
name = name[:i] + strings.Replace(name[i:], routePath, "", 1)
|
|
}
|
|
}
|
|
|
|
file, err := openFile(config.Filesystem, name)
|
|
if err != nil {
|
|
if !os.IsNotExist(err) {
|
|
return err
|
|
}
|
|
|
|
if err = next(c); err == nil {
|
|
return err
|
|
}
|
|
|
|
he, ok := err.(*echo.HTTPError)
|
|
if !(ok && config.HTML5 && he.Code == http.StatusNotFound) {
|
|
return err
|
|
}
|
|
|
|
file, err = openFile(config.Filesystem, filepath.Join(config.Root, config.Index))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
defer file.Close()
|
|
|
|
info, err := file.Stat()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if info.IsDir() {
|
|
index, err := openFile(config.Filesystem, filepath.Join(name, config.Index))
|
|
if err != nil {
|
|
if config.Browse {
|
|
return listDir(t, name, file, c.Response())
|
|
}
|
|
|
|
if os.IsNotExist(err) {
|
|
return next(c)
|
|
}
|
|
}
|
|
|
|
defer index.Close()
|
|
|
|
info, err = index.Stat()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return serveFile(c, index, info)
|
|
}
|
|
|
|
return serveFile(c, file, info)
|
|
}
|
|
}
|
|
}
|
|
|
|
func openFile(fs http.FileSystem, name string) (http.File, error) {
|
|
pathWithSlashes := filepath.ToSlash(name)
|
|
return fs.Open(pathWithSlashes)
|
|
}
|
|
|
|
func serveFile(c echo.Context, file http.File, info os.FileInfo) error {
|
|
http.ServeContent(c.Response(), c.Request(), info.Name(), info.ModTime(), file)
|
|
return nil
|
|
}
|
|
|
|
func listDir(t *template.Template, name string, dir http.File, res *echo.Response) (err error) {
|
|
files, err := dir.Readdir(-1)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
// Create directory index
|
|
res.Header().Set(echo.HeaderContentType, echo.MIMETextHTMLCharsetUTF8)
|
|
data := struct {
|
|
Name string
|
|
Files []interface{}
|
|
}{
|
|
Name: name,
|
|
}
|
|
for _, f := range files {
|
|
data.Files = append(data.Files, struct {
|
|
Name string
|
|
Dir bool
|
|
Size string
|
|
}{f.Name(), f.IsDir(), bytes.Format(f.Size())})
|
|
}
|
|
return t.Execute(res, data)
|
|
}
|