observertesthelper: move docker into separate package

A subsequent commit in this series needs to user observertesthelper's docker-related
helpers in a test, but that creates an import cycle. Resolve the import cycle by moving
docker-related helpers into a separate package and maintain backward compatibility by
introducing deprecated stubs in observertesthelper that call into that new package.

Signed-off-by: William Findlay <william.findlay@isovalent.com>

pkg/observer/observertesthelper/docker/docker.go

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Tetragon
+
+package docker
+
+import (
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+// DockerCreate creates a new docker container in the background. The container will
+// be killed and removed on test cleanup.
+// It returns the containerId on success, or an error if spawning the container failed.
+func DockerCreate(tb testing.TB, args ...string) (containerId string) {
+	// note: we are not using `--rm` so we can choose to wait on the container
+	// with `docker wait`. We remove it manually below in t.Cleanup instead
+	args = append([]string{"create"}, args...)
+	id, err := exec.Command("docker", args...).Output()
+	if err != nil {
+		tb.Fatalf("failed to spawn docker container %v: %s", args, err)
+	}
+
+	containerId = strings.TrimSpace(string(id))
+	tb.Cleanup(func() {
+		err := exec.Command("docker", "rm", "--force", containerId).Run()
+		if err != nil {
+			tb.Logf("failed to remove container %s: %s", containerId, err)
+		}
+	})
+
+	return containerId
+}
+
+// DockerStart starts a new docker container with a given ID.
+func DockerStart(tb testing.TB, id string) {
+	err := exec.Command("docker", "start", id).Run()
+	if err != nil {
+		tb.Fatalf("failed to start docker container %s: %s", id, err)
+	}
+}
+
+// dockerRun starts a new docker container in the background. The container will
+// be killed and removed on test cleanup.
+// It returns the containerId on success, or an error if spawning the container failed.
+func DockerRun(tb testing.TB, args ...string) (containerId string) {
+	// note: we are not using `--rm` so we can choose to wait on the container
+	// with `docker wait`. We remove it manually below in t.Cleanup instead
+	args = append([]string{"run", "--detach"}, args...)
+	id, err := exec.Command("docker", args...).Output()
+	if err != nil {
+		tb.Fatalf("failed to spawn docker container %v: %s", args, err)
+	}
+
+	containerId = strings.TrimSpace(string(id))
+	tb.Cleanup(func() {
+		err := exec.Command("docker", "rm", "--force", containerId).Run()
+		if err != nil {
+			tb.Logf("failed to remove container %s: %s", containerId, err)
+		}
+	})
+
+	return containerId
+}
+
+// dockerExec executes a command in a container.
+func DockerExec(tb testing.TB, id string, args ...string) {
+	args = append([]string{"exec", id}, args...)
+	err := exec.Command("docker", args...).Run()
+	if err != nil {
+		tb.Fatalf("failed to exec in docker container %v: %s", args, err)
+	}
+}

pkg/observer/observertesthelper/observer_test_helper.go

@@ -24,6 +24,7 @@ import (
 	"github.com/cilium/tetragon/pkg/encoder"
 	"github.com/cilium/tetragon/pkg/metricsconfig"
 	"github.com/cilium/tetragon/pkg/observer"
+	"github.com/cilium/tetragon/pkg/observer/observertesthelper/docker"
 	"github.com/cilium/tetragon/pkg/policyfilter"
 	"github.com/cilium/tetragon/pkg/tracingpolicy"
 	"github.com/sirupsen/logrus"
@@ -524,64 +525,29 @@ func ExecWGCurl(readyWG *sync.WaitGroup, retries uint, args ...string) error {
 // DockerCreate creates a new docker container in the background. The container will
 // be killed and removed on test cleanup.
 // It returns the containerId on success, or an error if spawning the container failed.
+// DEPRECATED: use docker.DockerCreate instead.
 func DockerCreate(tb testing.TB, args ...string) (containerId string) {
-	// note: we are not using `--rm` so we can choose to wait on the container
-	// with `docker wait`. We remove it manually below in t.Cleanup instead
-	args = append([]string{"create"}, args...)
-	id, err := exec.Command("docker", args...).Output()
-	if err != nil {
-		tb.Fatalf("failed to spawn docker container %v: %s", args, err)
-	}
-
-	containerId = strings.TrimSpace(string(id))
-	tb.Cleanup(func() {
-		err := exec.Command("docker", "rm", "--force", containerId).Run()
-		if err != nil {
-			tb.Logf("failed to remove container %s: %s", containerId, err)
-		}
-	})
-
-	return containerId
+	return docker.DockerCreate(tb, args...)
 }
 
 // DockerStart starts a new docker container with a given ID.
+// DEPRECATED: use docker.DockerStart instead.
 func DockerStart(tb testing.TB, id string) {
-	err := exec.Command("docker", "start", id).Run()
-	if err != nil {
-		tb.Fatalf("failed to start docker container %s: %s", id, err)
-	}
+	docker.DockerStart(tb, id)
 }
 
 // dockerRun starts a new docker container in the background. The container will
 // be killed and removed on test cleanup.
 // It returns the containerId on success, or an error if spawning the container failed.
+// DEPRECATED: use docker.DockerRun instead.
 func DockerRun(tb testing.TB, args ...string) (containerId string) {
-	// note: we are not using `--rm` so we can choose to wait on the container
-	// with `docker wait`. We remove it manually below in t.Cleanup instead
-	args = append([]string{"run", "--detach"}, args...)
-	id, err := exec.Command("docker", args...).Output()
-	if err != nil {
-		tb.Fatalf("failed to spawn docker container %v: %s", args, err)
-	}
-
-	containerId = strings.TrimSpace(string(id))
-	tb.Cleanup(func() {
-		err := exec.Command("docker", "rm", "--force", containerId).Run()
-		if err != nil {
-			tb.Logf("failed to remove container %s: %s", containerId, err)
-		}
-	})
-
-	return containerId
+	return docker.DockerRun(tb, args...)
 }
 
 // dockerExec executes a command in a container.
+// DEPRECATED: use docker.DockerExec instead.
 func DockerExec(tb testing.TB, id string, args ...string) {
-	args = append([]string{"exec", id}, args...)
-	err := exec.Command("docker", args...).Run()
-	if err != nil {
-		tb.Fatalf("failed to exec in docker container %v: %s", args, err)
-	}
+	docker.DockerExec(tb, id, args...)
 }
 
 type fakeK8sWatcher struct {