add support for local cnb caching (digitalocean#1216)

* add support for local cnb caching

* address pr feedback

args.go

@@ -66,6 +66,8 @@ const (
 	ArgClusterNodePool = "node-pool"
 	// ArgClusterUpdateKubeconfig updates the local kubeconfig.
 	ArgClusterUpdateKubeconfig = "update-kubeconfig"
+	// ArgNoCache represents whether or not to omit the cache on the next command.
+	ArgNoCache = "no-cache"
 	// ArgNodePoolName is a cluster's node pool name argument.
 	ArgNodePoolName = "name"
 	// ArgNodePoolCount is a cluster's node pool count argument.

commands/apps_dev.go

@@ -76,6 +76,12 @@ func AppsDev() *Command {
 		"Additional environment variables to inject into the build.",
 	)
 
+	AddBoolFlag(
+		build, doctl.ArgNoCache,
+		"", false,
+		"Whether or not to omit the cache for the build.",
+	)
+
 	AddStringFlag(
 		build, doctl.ArgAppDevBuildCommand,
 		"", "",
@@ -100,6 +106,10 @@ func AppsDev() *Command {
 // RunAppsDevBuild builds an app component locally.
 func RunAppsDevBuild(c *CmdConfig) error {
 	ctx := context.Background()
+	noCache, err := c.Doit.GetBool(c.NS, doctl.ArgNoCache)
+	if err != nil {
+		return err
+	}
 	timeout, err := c.Doit.GetDuration(c.NS, doctl.ArgTimeout)
 	if err != nil {
 		return err
@@ -253,6 +263,17 @@ func RunAppsDevBuild(c *CmdConfig) error {
 		return err
 	}
 
+	if noCache {
+		err = conf.ClearCacheDir(ctx, component)
+		if err != nil {
+			return err
+		}
+	}
+	err = conf.EnsureCacheDir(ctx, component)
+	if err != nil {
+		return err
+	}
+
 	if Interactive {
 		choice, err := confirm.New(
 			"start build?",
@@ -306,6 +327,8 @@ func RunAppsDevBuild(c *CmdConfig) error {
 
 		builder, err := c.componentBuilderFactory.NewComponentBuilder(cli, conf.contextDir, spec, builder.NewBuilderOpts{
 			Component:            component,
+			LocalCacheDir:        conf.CacheDir(component),
+			NoCache:              noCache,
 			Registry:             registryName,
 			EnvOverride:          envs,
 			BuildCommandOverride: buildOverrride,

commands/apps_dev_config.go

@@ -2,6 +2,7 @@ package commands
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -138,12 +139,6 @@ func RunAppsDevConfigUnset(c *CmdConfig) error {
 	return nil
 }
 
-type appDevConfig struct {
-	contextDir string
-	cmdConfig  *CmdConfig
-	viper      *viper.Viper
-}
-
 var validAppDevKeys = map[string]bool{
 	doctl.ArgApp:                true,
 	doctl.ArgAppSpec:            true,
@@ -161,6 +156,29 @@ func outputValidAppDevKeys() string {
 	return strings.Join(keys, ", ")
 }
 
+type appDevConfig struct {
+	contextDir string
+	cmdConfig  *CmdConfig
+	viper      *viper.Viper
+}
+
+func (c *appDevConfig) CacheDir(component string) string {
+	return filepath.Join(c.contextDir, ".do", "cache", component)
+}
+
+func (c *appDevConfig) EnsureCacheDir(ctx context.Context, component string) error {
+	err := os.MkdirAll(filepath.Join(c.contextDir, ".do", "cache", component), os.ModePerm)
+	if err != nil {
+		return err
+	}
+
+	return ensureStringInFile(filepath.Join(c.contextDir, ".do", ".gitignore"), "/cache")
+}
+
+func (c *appDevConfig) ClearCacheDir(ctx context.Context, component string) error {
+	return os.RemoveAll(filepath.Join(c.contextDir, ".do", "cache", component))
+}
+
 func (c *appDevConfig) WriteConfig() error {
 	return c.viper.WriteConfig()
 }

internal/apps/builder/builder.go

@@ -13,6 +13,8 @@ import (
 	"github.com/digitalocean/doctl/commands/charm"
 	"github.com/digitalocean/doctl/commands/charm/template"
 	"github.com/digitalocean/godo"
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
 )
 
 // ComponentBuilderFactory is the interface for creating a component builder.
@@ -41,6 +43,7 @@ type baseComponentBuilder struct {
 	envOverrides         map[string]string
 	buildCommandOverride string
 	copyOnWriteSemantics bool
+	noCache              bool
 
 	logWriter io.Writer
 }
@@ -99,6 +102,19 @@ func (b baseComponentBuilder) getEnvMap() (map[string]string, error) {
 	return envMap, nil
 }
 
+func (b *baseComponentBuilder) imageExists(ctx context.Context, ref string) (bool, error) {
+	images, err := b.cli.ImageList(ctx, types.ImageListOptions{
+		Filters: filters.NewArgs(filters.Arg("reference", ref)),
+	})
+	if err != nil {
+		return false, err
+	}
+	if len(images) < 1 {
+		return false, nil
+	}
+	return true, nil
+}
+
 // NewBuilderOpts ...
 type NewBuilderOpts struct {
 	Component            string
@@ -107,6 +123,8 @@ type NewBuilderOpts struct {
 	BuildCommandOverride string
 	LogWriter            io.Writer
 	Versioning           Versioning
+	LocalCacheDir        string
+	NoCache              bool
 }
 
 type Versioning struct {
@@ -156,9 +174,11 @@ func (f *DefaultComponentBuilderFactory) NewComponentBuilder(cli DockerEngineCli
 				opts.EnvOverride,
 				opts.BuildCommandOverride,
 				copyOnWriteSemantics,
+				opts.NoCache,
 				opts.LogWriter,
 			},
-			versioning: cnbVersioning,
+			versioning:    cnbVersioning,
+			localCacheDir: opts.LocalCacheDir,
 		}, nil
 	}
 
@@ -172,6 +192,7 @@ func (f *DefaultComponentBuilderFactory) NewComponentBuilder(cli DockerEngineCli
 			opts.EnvOverride,
 			opts.BuildCommandOverride,
 			copyOnWriteSemantics,
+			opts.NoCache,
 			opts.LogWriter,
 		},
 	}, nil

internal/apps/builder/cnb.go

@@ -22,16 +22,18 @@ import (
 
 const (
 	// CNBBuilderImage represents the local cnb builder.
-	CNBBuilderImage = "digitaloceanapps/cnb-local-builder:dev"
+	CNBBuilderImage = "digitaloceanapps/cnb-local-builder:v0.46.0"
 
 	appVarAllowListKey = "APP_VARS"
 	appVarPrefix       = "APP_VAR_"
+	cnbCacheDir        = "/cnb/cache"
 )
 
 // CNBComponentBuilder represents a CNB builder.
 type CNBComponentBuilder struct {
 	baseComponentBuilder
-	versioning CNBVersioning
+	versioning    CNBVersioning
+	localCacheDir string
 }
 
 // CNBVersioning contains CNB versioning config.
@@ -56,7 +58,7 @@ func (b *CNBComponentBuilder) Build(ctx context.Context) (res ComponentBuilderRe
 		return res, err
 	}
 
-	env, err := b.cnbEnv()
+	env, err := b.cnbEnv(ctx)
 	if err != nil {
 		return res, fmt.Errorf("configuring environment variables: %w", err)
 	}
@@ -74,6 +76,14 @@ func (b *CNBComponentBuilder) Build(ctx context.Context) (res ComponentBuilderRe
 		})
 	}
 
+	if b.localCacheDir != "" {
+		mounts = append(mounts, mount.Mount{
+			Type:   mount.TypeBind,
+			Source: b.localCacheDir,
+			Target: cnbCacheDir,
+		})
+	}
+
 	buildContainer, err := b.cli.ContainerCreate(ctx, &container.Config{
 		Image:        CNBBuilderImage,
 		Entrypoint:   []string{"sh", "-c", "sleep infinity"},
@@ -174,14 +184,14 @@ func (b *CNBComponentBuilder) Build(ctx context.Context) (res ComponentBuilderRe
 	return res, nil
 }
 
-func (b *CNBComponentBuilder) cnbEnv() ([]string, error) {
+func (b *CNBComponentBuilder) cnbEnv(ctx context.Context) ([]string, error) {
+	envs := []string{}
+	appVars := []string{}
+
 	envMap, err := b.getEnvMap()
 	if err != nil {
 		return nil, err
 	}
-	envs := []string{}
-
-	appVars := []string{}
 	for k, v := range envMap {
 		envs = append(envs, appVarPrefix+k+"="+v)
 		appVars = append(appVars, k)
@@ -217,6 +227,17 @@ func (b *CNBComponentBuilder) cnbEnv() ([]string, error) {
 		envs = append(envs, "VERSION_PINNING_LIST="+string(versioningJSON))
 	}
 
+	if exists, err := b.imageExists(ctx, b.ImageOutputName()); err != nil {
+		return nil, err
+	} else if exists {
+		envs = append(envs, "PREVIOUS_APP_IMAGE_URL="+b.ImageOutputName())
+	}
+
+	if b.localCacheDir != "" {
+		envs = append(envs, "APP_CACHE_DIR="+cnbCacheDir)
+	}
+
 	sort.Strings(envs)
+
 	return envs, nil
 }

internal/apps/builder/cnb_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/digitalocean/godo"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/require"
 )
@@ -86,6 +87,7 @@ func TestCNBComponentBuild(t *testing.T) {
 				},
 				buildCommandOverride: "custom build command",
 			},
+			localCacheDir: "/cache",
 		}
 
 		buildID := "build-id"
@@ -97,12 +99,16 @@ func TestCNBComponentBuild(t *testing.T) {
 			Force: true,
 		}).Return(nil)
 		mockClient.EXPECT().ContainerStart(ctx, buildID, types.ContainerStartOptions{}).Return(nil)
+		mockClient.EXPECT().ImageList(ctx, types.ImageListOptions{
+			Filters: filters.NewArgs(filters.Arg("reference", builder.ImageOutputName())),
+		}).Return([]types.ImageSummary{{ /*single entry*/ }}, nil)
 
 		execID := "exec-id"
 		mockClient.EXPECT().ContainerExecCreate(ctx, buildID, types.ExecConfig{
 			AttachStderr: true,
 			AttachStdout: true,
 			Env: []string{
+				"APP_CACHE_DIR=" + cnbCacheDir,
 				"APP_IMAGE_URL=" + builder.ImageOutputName(),
 				"APP_PLATFORM_COMPONENT_TYPE=" + string(service.GetType()),
 				appVarAllowListKey + "=build-arg-1,override-1,run-build-arg-1,useroverride-1",
@@ -112,6 +118,7 @@ func TestCNBComponentBuild(t *testing.T) {
 				appVarPrefix + "useroverride-1=newval",
 				"BUILD_COMMAND=" + builder.buildCommandOverride,
 				"CNB_UPLOAD_RETRY=1",
+				"PREVIOUS_APP_IMAGE_URL=" + builder.ImageOutputName(),
 				"SOURCE_DIR=" + service.GetSourceDir(),
 			},
 			Cmd: []string{"sh", "-c", "/.app_platform/build.sh"},
@@ -176,6 +183,10 @@ func TestCNBComponentBuild(t *testing.T) {
 
 		mockClient.EXPECT().CopyToContainer(ctx, buildID, filepath.Clean("/"), gomock.Any(), gomock.Any()).Return(nil)
 
+		mockClient.EXPECT().ImageList(ctx, types.ImageListOptions{
+			Filters: filters.NewArgs(filters.Arg("reference", builder.ImageOutputName())),
+		}).Return([]types.ImageSummary{ /*no entries*/ }, nil)
+
 		execID := "exec-id"
 		mockClient.EXPECT().ContainerExecCreate(ctx, buildID, types.ExecConfig{
 			AttachStderr: true,

internal/apps/builder/container.go

@@ -23,6 +23,7 @@ type DockerEngineClient interface {
 	ContainerExecCreate(ctx context.Context, container string, config types.ExecConfig) (types.IDResponse, error)
 	ContainerExecStart(ctx context.Context, execID string, config types.ExecStartCheck) error
 	ContainerExecInspect(ctx context.Context, execID string) (types.ContainerExecInspect, error)
-	ImageBuild(ctx context.Context, context io.Reader, options types.ImageBuildOptions) (types.ImageBuildResponse, error)
 	CopyToContainer(ctx context.Context, container, path string, content io.Reader, options types.CopyToContainerOptions) error
+	ImageBuild(ctx context.Context, context io.Reader, options types.ImageBuildOptions) (types.ImageBuildResponse, error)
+	ImageList(ctx context.Context, options types.ImageListOptions) ([]types.ImageSummary, error)
 }

internal/apps/builder/docker.go

@@ -71,6 +71,7 @@ func (b *DockerComponentBuilder) Build(ctx context.Context) (ComponentBuilderRes
 			b.ImageOutputName(),
 		},
 		BuildArgs: buildArgs,
+		NoCache:   b.noCache,
 	}
 	dockerRes, err := b.cli.ImageBuild(ctx, tar, opts)
 	if err != nil {

internal/apps/builder/docker_test.go

@@ -83,6 +83,7 @@ func TestDockerComponentBuild(t *testing.T) {
 				component:            service,
 				buildCommandOverride: "test",
 				logWriter:            &logBuf,
+				noCache:              true,
 			},
 		}
 
@@ -96,6 +97,7 @@ func TestDockerComponentBuild(t *testing.T) {
 				"override-1":      strPtr("newval"),
 				"run-build-arg-1": strPtr("run-build-val-1"),
 			},
+			NoCache: true,
 		}).Return(types.ImageBuildResponse{
 			Body: ioutil.NopCloser(strings.NewReader("")),
 		}, nil)