go-gemini/request.go
2021-02-08 12:32:49 -05:00

117 lines
2.7 KiB
Go

package gemini
import (
"bufio"
"context"
"crypto/tls"
"io"
"net"
"net/url"
)
// Request represents a Gemini request.
type Request struct {
// URL specifies the URL being requested.
URL *url.URL
// For client requests, Host specifies the host on which the URL is sought.
// Host must contain a port.
//
// This field is ignored by the server.
Host string
// Certificate specifies the TLS certificate to use for the request.
//
// On the server side, if the client provided a certificate then
// Certificate.Leaf is guaranteed to be non-nil.
Certificate *tls.Certificate
// RemoteAddr allows servers and other software to record the network
// address that sent the request.
//
// This field is ignored by the client.
RemoteAddr net.Addr
// TLS allows servers and other software to record information about the TLS
// connection on which the request was received.
//
// This field is ignored by the client.
TLS *tls.ConnectionState
// Context specifies the context to use for client requests.
// If Context is nil, the background context will be used.
Context context.Context
}
// NewRequest returns a new request. The host is inferred from the URL.
func NewRequest(rawurl string) (*Request, error) {
u, err := url.Parse(rawurl)
if err != nil {
return nil, err
}
return NewRequestFromURL(u), nil
}
// NewRequestFromURL returns a new request for the given URL.
// The host is inferred from the URL.
//
// Callers should be careful that the URL query is properly escaped.
// See the documentation for QueryEscape for more information.
func NewRequestFromURL(url *url.URL) *Request {
host := url.Host
if url.Port() == "" {
host += ":1965"
}
return &Request{
URL: url,
Host: host,
}
}
// ReadRequest reads a Gemini request from the provided io.Reader
func ReadRequest(r io.Reader) (*Request, error) {
// Read URL
br := bufio.NewReader(r)
rawurl, err := br.ReadString('\r')
if err != nil {
return nil, err
}
// Read terminating line feed
if b, err := br.ReadByte(); err != nil {
return nil, err
} else if b != '\n' {
return nil, ErrInvalidRequest
}
// Trim carriage return
rawurl = rawurl[:len(rawurl)-1]
// Validate URL
if len(rawurl) > 1024 {
return nil, ErrInvalidRequest
}
u, err := url.Parse(rawurl)
if err != nil {
return nil, err
}
if u.User != nil {
// User is not allowed
return nil, ErrInvalidURL
}
return &Request{URL: u}, nil
}
// Write writes the Gemini request to the provided buffered writer.
func (r *Request) Write(w *bufio.Writer) error {
url := r.URL.String()
// User is invalid
if r.URL.User != nil || len(url) > 1024 {
return ErrInvalidURL
}
if _, err := w.WriteString(url); err != nil {
return err
}
if _, err := w.Write(crlf); err != nil {
return err
}
return nil
}