integration-cli: don't build -test images if they already exist

There's no need to try to re-build the test images if they already
exist. This change makes basically no difference to the upstream
integration test-suite running, but for users who want to run the
integration-cli suite on a host machine (such as distributions doing
tests) this change allows images to be pre-loaded such that compilers
aren't needed on the test machine.

However, this does remove the accidental re-compilation of nnp-test, as
well as handling errors far more cleanly (previously if an error
occurred during a test build, further tests won't attempt to rebuild
it).

Signed-off-by: Aleksa Sarai <asarai@suse.de>

integration-cli/fixtures_linux_daemon_test.go

@@ -8,7 +8,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
-	"sync"
 
 	"github.com/docker/docker/integration-cli/checker"
 	"github.com/docker/docker/internal/test/fixtures/load"
@@ -24,17 +23,13 @@ type logT interface {
 	Logf(string, ...interface{})
 }
 
-var ensureSyscallTestOnce sync.Once
-
 func ensureSyscallTest(c *check.C) {
-	var doIt bool
-	ensureSyscallTestOnce.Do(func() {
-		doIt = true
-	})
-	if !doIt {
+	defer testEnv.ProtectImage(c, "syscall-test:latest")
+
+	// If the image already exists, there's nothing left to do.
+	if testEnv.HasExistingImage(c, "syscall-test:latest") {
 		return
 	}
-	defer testEnv.ProtectImage(c, "syscall-test:latest")
 
 	// if no match, must build in docker, which is significantly slower
 	// (slower mostly because of the vfs graphdriver)
@@ -93,6 +88,14 @@ func ensureSyscallTestBuild(c *check.C) {
 
 func ensureNNPTest(c *check.C) {
 	defer testEnv.ProtectImage(c, "nnp-test:latest")
+
+	// If the image already exists, there's nothing left to do.
+	if testEnv.HasExistingImage(c, "nnp-test:latest") {
+		return
+	}
+
+	// if no match, must build in docker, which is significantly slower
+	// (slower mostly because of the vfs graphdriver)
 	if testEnv.OSType != runtime.GOOS {
 		ensureNNPTestBuild(c)
 		return

internal/test/environment/environment.go

@@ -8,9 +8,12 @@ import (
 	"strings"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/client"
+	"github.com/docker/docker/internal/test"
 	"github.com/docker/docker/internal/test/fixtures/load"
 	"github.com/pkg/errors"
+	"gotest.tools/assert"
 )
 
 // Execution contains information about the current test execution and daemon
@@ -151,6 +154,26 @@ func (e *Execution) IsUserNamespace() bool {
 	return root != ""
 }
 
+// HasExistingImage checks whether there is an image with the given reference.
+// Note that this is done by filtering and then checking whether there were any
+// results -- so ambiguous references might result in false-positives.
+func (e *Execution) HasExistingImage(t testingT, reference string) bool {
+	if ht, ok := t.(test.HelperT); ok {
+		ht.Helper()
+	}
+	client := e.APIClient()
+	filter := filters.NewArgs()
+	filter.Add("dangling", "false")
+	filter.Add("reference", reference)
+	imageList, err := client.ImageList(context.Background(), types.ImageListOptions{
+		All:     true,
+		Filters: filter,
+	})
+	assert.NilError(t, err, "failed to list images")
+
+	return len(imageList) > 0
+}
+
 // EnsureFrozenImagesLinux loads frozen test images into the daemon
 // if they aren't already loaded
 func EnsureFrozenImagesLinux(testEnv *Execution) error {