Add support for build environment variables (digitalocean#1209)

internal/apps/builder/builder.go

@@ -10,6 +10,8 @@ import (
 	"os"
 	"time"
 
+	"github.com/MakeNowJust/heredoc"
+	"github.com/digitalocean/doctl/commands/charm"
 	"github.com/digitalocean/godo"
 )
 
@@ -51,6 +53,56 @@ func (b baseComponentBuilder) getLogWriter() io.Writer {
 	return b.logWriter
 }
 
+func (b baseComponentBuilder) getEnvMap() map[string]string {
+	envs := map[string]string{}
+
+	charm.TemplatePrint(heredoc.Doc(`
+		{{success checkmark}} configuring build environment variables... {{nl}}{{nl}}`,
+	), nil)
+
+	if b.spec != nil {
+		for _, e := range b.spec.Envs {
+			if e.Type == godo.AppVariableType_Secret {
+				charm.TemplatePrint(heredoc.Doc(`
+					=> Ignoring SECRET variable {{highlight .GetKey}}{{nl}}`,
+				), e)
+				continue
+			}
+			if e.Scope != godo.AppVariableScope_RunTime {
+				val := e.Value
+				envs[e.Key] = val
+			}
+		}
+	}
+
+	for _, e := range b.component.GetEnvs() {
+		if e.Type == godo.AppVariableType_Secret {
+			charm.TemplatePrint(heredoc.Doc(`
+					=> Ignoring SECRET variable {{highlight .GetKey}}{{nl}}`,
+			), e)
+			continue
+		}
+		if e.Scope != godo.AppVariableScope_RunTime {
+			val := e.Value
+			envs[e.Key] = val
+		}
+	}
+
+	for k, v := range b.envOverrides {
+		v := v
+		if _, ok := envs[k]; ok {
+			charm.TemplatePrint(heredoc.Doc(`
+					=> Overwriting {{highlight .}} with provided env value{{nl}}`,
+			), k)
+		}
+		envs[k] = v
+	}
+
+	charm.TemplatePrint(heredoc.Doc(`{{nl}}`), nil)
+
+	return envs
+}
+
 // NewBuilderOpts ...
 type NewBuilderOpts struct {
 	Component string

internal/apps/builder/cnb.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"os"
 	"sort"
+	"strings"
 	"time"
 
 	"github.com/docker/docker/api/types"
@@ -16,6 +17,9 @@ import (
 const (
 	// CNBBuilderImage represents the local cnb builder.
 	CNBBuilderImage = "digitaloceanapps/cnb-local-builder:dev"
+
+	appVarAllowListKey = "APP_VARS"
+	appVarPrefix       = "APP_VAR_"
 )
 
 // CNBComponentBuilder represents a CNB builder
@@ -117,13 +121,29 @@ func (b *CNBComponentBuilder) Build(ctx context.Context) (res ComponentBuilderRe
 }
 
 func (b *CNBComponentBuilder) cnbEnv() []string {
-	args := getBuildArgs(b.spec, b.component, b.envOverrides)
+	envMap := b.getEnvMap()
 	envs := []string{}
-	for k, v := range args {
-		// NOTE(ntate) getBuildArgs already preprends _APP
-		envs = append(envs, k+"="+*v)
+
+	appVars := []string{}
+	for k, v := range envMap {
+		envs = append(envs, appVarPrefix+k+"="+v)
+		appVars = append(appVars, k)
 	}
+	if len(appVars) > 0 {
+		sort.Strings(appVars)
+		envs = append(envs, appVarAllowListKey+"="+strings.Join(appVars, ","))
+	}
+
 	envs = append(envs, "APP_IMAGE_URL="+b.ImageOutputName())
+	envs = append(envs, "APP_PLATFORM_COMPONENT_TYPE="+string(b.component.GetType()))
+	if b.component.GetSourceDir() != "" {
+		envs = append(envs, "SOURCE_DIR="+b.component.GetSourceDir())
+	}
+	if b.component.GetBuildCommand() != "" {
+		envs = append(envs, "BUILD_COMMAND="+b.component.GetBuildCommand())
+	}
+
 	sort.Strings(envs)
+
 	return envs
 }

internal/apps/builder/cnb_test.go

@@ -94,10 +94,11 @@ func TestCNBComponentBuild(t *testing.T) {
 			Env: []string{
 				"APP_IMAGE_URL=" + builder.ImageOutputName(),
 				"APP_PLATFORM_COMPONENT_TYPE=" + string(service.GetType()),
+				appVarAllowListKey + "=build-arg-1,override-1,run-build-arg-1",
+				appVarPrefix + "build-arg-1=build-val-1",
+				appVarPrefix + "override-1=newval",
+				appVarPrefix + "run-build-arg-1=run-build-val-1",
 				"SOURCE_DIR=" + service.GetSourceDir(),
-				"build-arg-1=build-val-1",
-				"override-1=newval",
-				"run-build-arg-1=run-build-val-1",
 			},
 			Cmd: []string{"sh", "-c", "/.app_platform/build.sh"},
 		}).Return(types.IDResponse{

internal/apps/builder/docker.go

@@ -10,8 +10,6 @@ import (
 	"path/filepath"
 	"time"
 
-	"github.com/digitalocean/godo"
-
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/pkg/archive"
 )
@@ -58,7 +56,7 @@ func (b *DockerComponentBuilder) Build(ctx context.Context) (ComponentBuilderRes
 		Tags: []string{
 			b.ImageOutputName(),
 		},
-		BuildArgs: getBuildArgs(b.spec, b.component, b.envOverrides),
+		BuildArgs: b.getBuildArgs(),
 	}
 	dockerRes, err := b.cli.ImageBuild(ctx, tar, opts)
 	if err != nil {
@@ -73,49 +71,15 @@ func (b *DockerComponentBuilder) Build(ctx context.Context) (ComponentBuilderRes
 	return res, nil
 }
 
-// TODO(ntate) doesn't handle encrypted secrets
-func getBuildArgs(spec *godo.AppSpec, component godo.AppBuildableComponentSpec, userEnv map[string]string) map[string]*string {
+func (b *DockerComponentBuilder) getBuildArgs() map[string]*string {
+	envMap := b.getEnvMap()
 	args := map[string]*string{}
 
-	if spec != nil {
-		for _, e := range spec.Envs {
-			if e.Type == godo.AppVariableType_Secret {
-				fmt.Printf("--> Ignoring SECRET variable %s\n", e.Key)
-				continue
-			}
-			if e.Scope != godo.AppVariableScope_RunTime {
-				val := e.Value
-				args[e.Key] = &val
-			}
-		}
-	}
-
-	for _, e := range component.GetEnvs() {
-		if e.Type == godo.AppVariableType_Secret {
-			fmt.Printf("--> Ignoring SECRET variable %s\n", e.Key)
-			continue
-		}
-		if e.Scope != godo.AppVariableScope_RunTime {
-			val := e.Value
-			args[e.Key] = &val
-		}
-	}
-
-	for k, v := range userEnv {
+	for k, v := range envMap {
 		v := v
-		if _, ok := args[k]; ok {
-			fmt.Printf("--> Overwriting %s with provided env value...\n", k)
-		}
 		args[k] = &v
 	}
 
-	cType := string(component.GetType())
-	args["APP_PLATFORM_COMPONENT_TYPE"] = &cType
-	if component.GetSourceDir() != "" {
-		dir := component.GetSourceDir()
-		args["SOURCE_DIR"] = &dir
-	}
-
 	return args
 }
 

internal/apps/builder/docker_test.go

@@ -86,11 +86,9 @@ func TestDockerComponentBuild(t *testing.T) {
 				builder.ImageOutputName(),
 			},
 			BuildArgs: map[string]*string{
-				"APP_PLATFORM_COMPONENT_TYPE": strPtr(string(service.GetType())),
-				"SOURCE_DIR":                  strPtr(service.GetSourceDir()),
-				"build-arg-1":                 strPtr("build-val-1"),
-				"override-1":                  strPtr("newval"),
-				"run-build-arg-1":             strPtr("run-build-val-1"),
+				"build-arg-1":     strPtr("build-val-1"),
+				"override-1":      strPtr("newval"),
+				"run-build-arg-1": strPtr("run-build-val-1"),
 			},
 		}).Return(types.ImageBuildResponse{
 			Body: ioutil.NopCloser(strings.NewReader("")),