Add function to get docker resource by name (#172)

dockertest.go

@@ -329,6 +329,34 @@ func (d *Pool) Run(repository, tag string, env []string) (*Resource, error) {
 	return d.RunWithOptions(&RunOptions{Repository: repository, Tag: tag, Env: env})
 }
 
+// ContainerByName finds a container with the given name and returns it if present
+func (d *Pool) ContainerByName(containerName string) (*Resource, bool) {
+	containers, err := d.Client.ListContainers(dc.ListContainersOptions{
+		All: true,
+		Filters: map[string][]string{
+			"name": {containerName},
+		},
+	})
+
+	if err != nil {
+		return nil, false
+	}
+
+	if len(containers) == 0 {
+		return nil, false
+	}
+
+	c, err := d.Client.InspectContainer(containers[0].ID)
+	if err != nil {
+		return nil, false
+	}
+
+	return &Resource{
+		pool:      d,
+		Container: c,
+	}, true
+}
+
 // RemoveContainerByName find a container with the given name and removes it if present
 func (d *Pool) RemoveContainerByName(containerName string) error {
 	containers, err := d.Client.ListContainers(dc.ListContainersOptions{

dockertest_test.go

@@ -183,6 +183,23 @@ func TestContainerWithShMzSize(t *testing.T) {
 	require.Nil(t, pool.Purge(resource))
 }
 
+func TestContainerByName(t *testing.T) {
+	got, err := pool.RunWithOptions(
+		&RunOptions{
+			Name:       "db",
+			Repository: "postgres",
+			Tag:        "9.5",
+		})
+	require.Nil(t, err)
+
+	want, ok := pool.ContainerByName("db")
+	require.True(t, ok)
+
+	require.Equal(t, got, want)
+
+	require.Nil(t, pool.Purge(got))
+}
+
 func TestRemoveContainerByName(t *testing.T) {
 	_, err := pool.RunWithOptions(
 		&RunOptions{