Initial commit

caddy_anubis.go

@@ -0,0 +1,120 @@
+package caddyanubis
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+
+	"github.com/TecharoHQ/anubis"
+	libanubis "github.com/TecharoHQ/anubis/lib"
+	"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("anubis", parseCaddyfile)
+}
+
+// Middleware implements an HTTP handler that writes the
+// visitor's IP address to a file or stream.
+type Middleware struct {
+	// The file or stream to write to. Can be "stdout"
+	// or "stderr".
+	Output string `json:"output,omitempty"`
+
+	w io.Writer
+}
+
+// CaddyModule returns the Caddy module information.
+func (Middleware) CaddyModule() caddy.ModuleInfo {
+	return caddy.ModuleInfo{
+		ID:  "http.handlers.anubis",
+		New: func() caddy.Module { return new(Middleware) },
+	}
+}
+
+// Provision implements caddy.Provisioner.
+func (m *Middleware) Provision(ctx caddy.Context) error {
+	switch m.Output {
+	case "stdout":
+		m.w = os.Stdout
+	case "stderr":
+		m.w = os.Stderr
+	default:
+		return fmt.Errorf("an output stream is required")
+	}
+	return nil
+}
+
+// Validate implements caddy.Validator.
+func (m *Middleware) Validate() error {
+	if m.w == nil {
+		return fmt.Errorf("no writer")
+	}
+	return nil
+}
+
+// ServeHTTP implements caddyhttp.MiddlewareHandler.
+func (m Middleware) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
+	m.w.Write([]byte(r.RemoteAddr))
+
+	policy, err := libanubis.LoadPoliciesOrDefault("", anubis.DefaultDifficulty)
+	if err != nil {
+		return err
+	}
+
+	errChan := make(chan error)
+	anubisServer, err := libanubis.New(libanubis.Options{
+		Next: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			errChan <- next.ServeHTTP(w, r)
+		}),
+		Policy:         policy,
+		ServeRobotsTXT: true,
+	})
+
+	if err != nil {
+		return err
+	}
+
+	anubisServer.ServeHTTP(w, r)
+
+	for err := range errChan {
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// UnmarshalCaddyfile implements caddyfile.Unmarshaler.
+func (m *Middleware) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
+	d.Next() // consume directive name
+
+	// require an argument
+	if !d.NextArg() {
+		return d.ArgErr()
+	}
+
+	// store the argument
+	m.Output = d.Val()
+	return nil
+}
+
+// parseCaddyfile unmarshals tokens from h into a new Middleware.
+func parseCaddyfile(h httpcaddyfile.Helper) (caddyhttp.MiddlewareHandler, error) {
+	var m Middleware
+	err := m.UnmarshalCaddyfile(h.Dispenser)
+	return m, err
+}
+
+// Interface guards
+var (
+	_ caddy.Provisioner           = (*Middleware)(nil)
+	_ caddy.Validator             = (*Middleware)(nil)
+	_ caddyhttp.MiddlewareHandler = (*Middleware)(nil)
+	_ caddyfile.Unmarshaler       = (*Middleware)(nil)
+)