Supporting proxied Docker APIs through DOCKER_HOST (#70)

.circleci/config.yml

@@ -3,7 +3,7 @@ version: 2.1
 jobs:
   canary:
     machine:
-      image: ubuntu-1604:202007-01
+      image: ubuntu-2004:202201-02
     working_directory: ~/docker-volume-backup
     steps:
       - checkout
@@ -19,6 +19,7 @@ jobs:
           name: Run tests
           working_directory: ~/docker-volume-backup/test
           command: |
+            export GPG_TTY=$(tty)
             ./test.sh canary
 
   build:

README.md

@@ -80,7 +80,8 @@ services:
       - data:/backup/my-app-backup:ro
       # Mounting the Docker socket allows the script to stop and restart
       # the container during backup. You can omit this if you don't want
-      # to stop the container
+      # to stop the container. In case you need to proxy the socket, you can
+      # also provide a location by setting `DOCKER_HOST` in the container
       - /var/run/docker.sock:/var/run/docker.sock:ro
       # If you mount a local directory or volume to `/archive` a local
       # copy of the backup will be stored there. You can override the

cmd/backup/script.go

@@ -73,7 +73,7 @@ func newScript() (*script, error) {
 
 	s.registerHook(hookLevelPlumbing, func(error) error {
 		s.stats.EndTime = time.Now()
-		s.stats.TookTime = s.stats.EndTime.Sub(s.stats.EndTime)
+		s.stats.TookTime = s.stats.EndTime.Sub(s.stats.StartTime)
 		return nil
 	})
 
@@ -90,7 +90,8 @@ func newScript() (*script, error) {
 	s.file = timeutil.Strftime(&s.stats.StartTime, s.file)
 
 	_, err := os.Stat("/var/run/docker.sock")
-	if !os.IsNotExist(err) {
+	_, dockerHostSet := os.LookupEnv("DOCKER_HOST")
+	if !os.IsNotExist(err) || dockerHostSet {
 		cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
 		if err != nil {
 			return nil, fmt.Errorf("newScript: failed to create docker client")

test/compose/run.sh

@@ -32,7 +32,7 @@ docker run --rm -it \
 
 echo "[TEST:PASS] Found relevant files in decrypted and untared remote backups."
 
-echo 1234secret | gpg -d --yes --passphrase-fd 0 ./local/test-hostnametoken.tar.gz.gpg > ./local/decrypted.tar.gz
+echo 1234secret | gpg -d --pinentry-mode loopback --yes --passphrase-fd 0 ./local/test-hostnametoken.tar.gz.gpg > ./local/decrypted.tar.gz
 tar -xf ./local/decrypted.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db
 rm ./local/decrypted.tar.gz
 test -L /tmp/backup/app_data/db.link