Automatically find gpg-agent socket path

.travis.yml

@@ -1,3 +1,4 @@
+go_import_path: github.com/prep/gpg
 dist: xenial
 
 language: go
@@ -16,11 +17,7 @@ before_install:
   - sudo apt-get update
   - sudo apt-get install -y gpgv2
 
-# Start the gpg-agent in the background before running the test suite.
-before_script:
-  - gpg-agent --homedir testdata/gnupg --daemon
-
 script:
   - GO_FILES=$(find . -iname '*.go' -type f | grep -v /vendor/)
   - test -z $(gofmt -s -l $GO_FILES)
-  - go test -v -race ./...
+  - ./runtests.sh -v -race ./...

README.md

@@ -1,5 +1,5 @@
 gpg-agent
-[![TravisCI](https://travis-ci.org/prep/gpg.svg?branch=master)](https://travis-ci.org/prep/gpg.svg?branch=master)
+[![TravisCI](https://travis-ci.org/prep/gpg.svg?branch=master)](https://travis-ci.org/prep/gpg?branch=master)
 [![Go Report Card](https://goreportcard.com/badge/github.com/prep/gpg)](https://goreportcard.com/report/github.com/prep/gpg)
 [![GoDoc](https://godoc.org/github.com/prep/gpg/agent?status.svg)](https://godoc.org/github.com/prep/gpg/agent)
 =========
@@ -19,6 +19,12 @@ TODO
 ----
 * There are possibly some unnecessary type conversions happening because `bufio.ReadString()` is used as opposed to `bufio.ReadBytes()`.
 
+Running Tests
+-------------
+
+The tests need a running gpg-agent with the GNUPGHOME environment variable set to the testdata/gnupg directory. To simplify running tests,
+use the `runtests.sh` wrapper script which will set GNUPGHOME, start gpg-agent then run `go test` for you.
+
 License
 -------
 This software is distributed under the BSD-style license found in the LICENSE file.

agent/conn.go

@@ -3,9 +3,12 @@ package agent
 import (
 	"bufio"
 	"crypto"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"net"
+	"os/exec"
+	"regexp"
 
 	"strings"
 	"sync"
@@ -28,7 +31,17 @@ type Conn struct {
 
 // Dial connects to the specified unix domain socket and checks if there is a
 // live GPG agent on the other end.
+// If filename is "", try to find the path the socket automatically
+// by calling gpgconf --list-dirs (see findAgentSocket).
 func Dial(filename string, options []string) (*Conn, error) {
+	if filename == "" {
+		var err error
+		filename, err = findAgentSocket()
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	c, err := net.Dial("unix", filename)
 	if err != nil {
 		return nil, err
@@ -48,6 +61,24 @@ func Dial(filename string, options []string) (*Conn, error) {
 	return conn, nil
 }
 
+// Find the agent socket by calling the gpgconf program and parse its output
+func findAgentSocket() (string, error) {
+	re := regexp.MustCompile("agent-socket:(.*)\n")
+
+	out, err := exec.Command("gpgconf", "--list-dirs").Output()
+	if err != nil {
+		return "", err
+	}
+
+	filename := re.FindStringSubmatch(string(out))
+
+	if filename == nil {
+		return "", errors.New("agent-socket path not found in gpgconf output")
+	}
+
+	return filename[1], nil
+}
+
 // request sends a request to the pgp-agent and then returns its response.
 func (conn *Conn) request(format string, a ...interface{}) error {
 	req := fmt.Sprintf(format+"\n", a...)

agent/conn_test.go

@@ -15,7 +15,7 @@ func init() {
 	}
 
 	var err error
-	if conn, err = Dial("../testdata/gnupg/S.gpg-agent", options); err != nil {
+	if conn, err = Dial("", options); err != nil {
 		panic(err.Error())
 	}
 }

runtests.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+export GNUPGHOME=${DIR}/testdata/gnupg
+
+gpg-connect-agent reloadagent /bye
+
+go test $@