Docker: restore "from env" behavior, and perform API version negotiat…

…ion (golang-migrate#270)

* NewDockerContainer: restore "from env" behavior

commit c31948c replaced the deprecated
`dockerclient.NewEnvClient` with `dockerclient.NewClientWithOpts`, but
did not add the `FromEnv` option to keep  the old behavior.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

* NewDockerContainer: use API version negotiation

This helps in situations where the daemon is older than
the API client. API version negotiation checks the maximum
supported API version by the daemon, and downgrades to that
API version if needed.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/cznic/ql v1.2.0
 	github.com/denisenkom/go-mssqldb v0.0.0-20190515213511-eb9f6a1743f3
 	github.com/dhui/dktest v0.3.0
-	github.com/docker/docker v0.7.3-0.20190108045446-77df18c24acf
+	github.com/docker/docker v0.7.3-0.20190817195342-4760db040282
 	github.com/fsouza/fake-gcs-server v1.7.0
 	github.com/go-sql-driver/mysql v1.4.1
 	github.com/gocql/gocql v0.0.0-20190301043612-f6df8288f9b4

go.sum

@@ -58,6 +58,8 @@ github.com/docker/distribution v2.7.0+incompatible/go.mod h1:J2gT2udsDAN96Uj4Kfc
 github.com/docker/docker v0.7.3-0.20190103212154-2b7e084dc98b/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/docker v0.7.3-0.20190108045446-77df18c24acf h1:2v/98rHzs3v6X0AHtoCH9u+e56SdnpogB1Z2fFe1KqQ=
 github.com/docker/docker v0.7.3-0.20190108045446-77df18c24acf/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v0.7.3-0.20190817195342-4760db040282 h1:mzrx39dGtGq0VEnTHjnakmczd4uFbhx2cZU3BJDsLdc=
+github.com/docker/docker v0.7.3-0.20190817195342-4760db040282/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKohAFqRJQ=
 github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
 github.com/docker/go-units v0.3.3 h1:Xk8S3Xj5sLGlG5g67hJmYMmUgXv5N4PhkjJHHqrwnTk=

testing/docker.go

@@ -23,7 +23,10 @@ import (
 )
 
 func NewDockerContainer(t testing.TB, image string, env []string, cmd []string) (*DockerContainer, error) {
-	c, err := dockerclient.NewClientWithOpts()
+	c, err := dockerclient.NewClientWithOpts(
+		dockerclient.FromEnv,
+		dockerclient.WithAPIVersionNegotiation(),
+	)
 	if err != nil {
 		return nil, err
 	}