gopher support.

Some of the contrib packages were originally built gemini-specific and
had to be refactored into generic core functionality and thin
protocol-specific wrappers for each of gemini and gopher.

1 files changed, 55 insertions, 0 deletions

diff --git a/gopher/client.go b/gopher/client.go
new file mode 100644
index 0000000..8f5ca81
--- /dev/null
+++ b/gopher/client.go
@@ -0,0 +1,55 @@
+package gopher
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"net"
+
+	"tildegit.org/tjp/gus"
+)
+
+// Client is used for sending gopher requests and producing the responses.
+//
+// It carries no state and is reusable simultaneously by multiple goroutines.
+//
+// The zero value is immediately usable.
+type Client struct{}
+
+// RoundTrip sends a single gopher request and returns its response.
+func (c Client) RoundTrip(request *gus.Request) (*gus.Response, error) {
+	if request.Scheme != "gopher" && request.Scheme != "" {
+		return nil, errors.New("non-gopher protocols not supported")
+	}
+
+	host := request.Host
+	if _, port, _ := net.SplitHostPort(host); port == "" {
+		host = net.JoinHostPort(host, "70")
+	}
+
+	conn, err := net.Dial("tcp", host)
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+
+	request.RemoteAddr = conn.RemoteAddr()
+	request.TLSState = nil
+
+	requestBody := request.Path
+	if request.RawQuery != "" {
+		requestBody += "\t" + request.UnescapedQuery()
+	}
+	requestBody += "\r\n"
+
+	if _, err := conn.Write([]byte(requestBody)); err != nil {
+		return nil, err
+	}
+
+	response, err := io.ReadAll(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	return &gus.Response{Body: bytes.NewBuffer(response)}, nil
+}