look for DBUS_SESSION_BUS_ADDRESS if not set
if DBUS_SESSION_BUS_ADDRESS is not set (like if running from crontab)
we end up with a fresh dbus session. This breaks things like access to
secret service (password manager).
If DBUS_SESSION_BUS_ADDRESS is empty, look in several locations inside
XDG_RUNTIME_DIR (/run/user/<uid>/) and if an existing dbus session bus
address is found, update DBUS_SESSION_BUS_ADDRESS with that and
continue.
diff --git a/conn.go b/conn.go
index 02471a5..b38920b 100644
--- a/conn.go
+++ b/conn.go
@@ -77,8 +77,11 @@
}
func getSessionBusAddress() (string, error) {
- address := os.Getenv("DBUS_SESSION_BUS_ADDRESS")
- if address != "" && address != "autolaunch:" {
+ if address := os.Getenv("DBUS_SESSION_BUS_ADDRESS"); address != "" && address != "autolaunch:" {
+ return address, nil
+
+ } else if address := tryDiscoverDbusSessionBusAddress(); address != "" {
+ os.Setenv("DBUS_SESSION_BUS_ADDRESS", address)
return address, nil
}
return getSessionBusPlatformAddress()
diff --git a/conn_other.go b/conn_other.go
index 0a73c50..289044a 100644
--- a/conn_other.go
+++ b/conn_other.go
@@ -5,8 +5,13 @@
import (
"bytes"
"errors"
+ "fmt"
+ "io/ioutil"
"os"
"os/exec"
+ "os/user"
+ "path"
+ "strings"
)
func getSessionBusPlatformAddress() (string, error) {
@@ -30,3 +35,57 @@
return addr, nil
}
+// tryDiscoverDbusSessionBusAddress tries to discover an existing dbus session
+// and return the value of its DBUS_SESSION_BUS_ADDRESS.
+// It tries different techniques employed by different operating systems,
+// returning the first valid address it finds, or an empty string.
+//
+// * /run/user/<uid>/bus if this exists, it *is* the bus socket. present on
+// Ubuntu 18.04
+// * /run/user/<uid>/dbus-session: if this exists, it can be parsed for the bus
+// address. present on Ubuntu 16.04
+//
+// See https://dbus.freedesktop.org/doc/dbus-launch.1.html
+func tryDiscoverDbusSessionBusAddress() string {
+ if runtimeDirectory, err := getRuntimeDirectory(); err == nil {
+
+ if runUserBusFile := path.Join(runtimeDirectory, "bus"); fileExists(runUserBusFile) {
+ // if /run/user/<uid>/bus exists, that file itself
+ // *is* the unix socket, so return its path
+ return fmt.Sprintf("unix:path=%s", runUserBusFile)
+ }
+ if runUserSessionDbusFile := path.Join(runtimeDirectory, "dbus-session"); fileExists(runUserSessionDbusFile) {
+ // if /run/user/<uid>/dbus-session exists, it's a
+ // text file // containing the address of the socket, e.g.:
+ // DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-E1c73yNqrG
+
+ if f, err := ioutil.ReadFile(runUserSessionDbusFile); err == nil {
+ fileContent := string(f)
+
+ prefix := "DBUS_SESSION_BUS_ADDRESS="
+
+ if strings.HasPrefix(fileContent, prefix) {
+ address := strings.TrimRight(strings.TrimPrefix(fileContent, prefix), "\n\r")
+ return address
+ }
+ }
+ }
+ }
+ return ""
+}
+
+func getRuntimeDirectory() (string, error) {
+ if currentUser, err := user.Current(); err != nil {
+ return "", err
+ } else {
+ return fmt.Sprintf("/run/user/%s", currentUser.Uid), nil
+ }
+}
+
+func fileExists(filename string) bool {
+ if _, err := os.Stat(filename); !os.IsNotExist(err) {
+ return true
+ } else {
+ return false
+ }
+}
