add multiple template base path functionality

cmd/ack-generate/command/apis.go

@@ -85,7 +85,7 @@ func generateAPIs(cmd *cobra.Command, args []string) error {
 	if err != nil {
 		return err
 	}
-	ts, err := ackgenerate.APIs(g, optTemplatesDir)
+	ts, err := ackgenerate.APIs(g, optTemplateDirs)
 	if err != nil {
 		return err
 	}

cmd/ack-generate/command/controller.go

@@ -82,7 +82,7 @@ func generateController(cmd *cobra.Command, args []string) error {
 	if err != nil {
 		return err
 	}
-	ts, err := ackgenerate.Controller(g, optTemplatesDir)
+	ts, err := ackgenerate.Controller(g, optTemplateDirs)
 	if err != nil {
 		return err
 	}

cmd/ack-generate/command/crossplane.go

@@ -53,7 +53,6 @@ func generateCrossplane(_ *cobra.Command, args []string) error {
 	if err := ensureSDKRepo(optCacheDir); err != nil {
 		return err
 	}
-	optTemplatesDir = filepath.Join(optTemplatesDir, "crossplane")
 	svcAlias := strings.ToLower(args[0])
 	sdkHelper := model.NewSDKHelper(sdkDir)
 	sdkHelper.APIGroupSuffix = "aws.crossplane.io"
@@ -83,7 +82,7 @@ func generateCrossplane(_ *cobra.Command, args []string) error {
 		return err
 	}
 
-	ts, err := cpgenerate.Crossplane(g, optTemplatesDir)
+	ts, err := cpgenerate.Crossplane(g, optTemplateDirs)
 	if err != nil {
 		return err
 	}

cmd/ack-generate/command/olm.go

@@ -138,7 +138,7 @@ func generateOLMAssets(cmd *cobra.Command, args []string) error {
 	}
 
 	// generate templates
-	ts, err := olmgenerate.BundleAssets(g, commonMeta, svcConf, version, optTemplatesDir)
+	ts, err := olmgenerate.BundleAssets(g, commonMeta, svcConf, version, optTemplateDirs)
 	if err != nil {
 		return err
 	}

cmd/ack-generate/command/release.go

@@ -87,7 +87,7 @@ func generateRelease(cmd *cobra.Command, args []string) error {
 		return err
 	}
 	ts, err := ackgenerate.Release(
-		g, optTemplatesDir,
+		g, optTemplateDirs,
 		releaseVersion, optImageRepository, optServiceAccountName,
 	)
 	if err != nil {

cmd/ack-generate/command/root.go

@@ -38,8 +38,8 @@ var (
 	optCacheDir            string
 	optRefreshCache        bool
 	optAWSSDKGoVersion     string
-	defaultTemplatesDir    string
-	optTemplatesDir        string
+	defaultTemplateDirs    []string
+	optTemplateDirs        []string
 	defaultServicesDir     string
 	optServicesDir         string
 	optDryRun              bool
@@ -80,7 +80,7 @@ func init() {
 	for _, tryPath := range tryPaths {
 		if fi, err := os.Stat(tryPath); err == nil {
 			if fi.IsDir() {
-				defaultTemplatesDir = tryPath
+				defaultTemplateDirs = append(defaultTemplateDirs, tryPath)
 				break
 			}
 		}
@@ -100,8 +100,8 @@ func init() {
 	rootCmd.PersistentFlags().BoolVar(
 		&optDryRun, "dry-run", false, "If true, outputs all files to stdout",
 	)
-	rootCmd.PersistentFlags().StringVar(
-		&optTemplatesDir, "templates-dir", defaultTemplatesDir, "Path to directory with templates to use in code generation",
+	rootCmd.PersistentFlags().StringSliceVar(
+		&optTemplateDirs, "template-dirs", defaultTemplateDirs, "Paths to directories with templates to use in code generation. Note that the order in which directories is specified will be used to provide override functionality.",
 	)
 	rootCmd.PersistentFlags().StringVar(
 		&optServicesDir, "services-dir", defaultServicesDir, "Path to directory to output service-specific code",

pkg/generate/ack/apis.go

@@ -46,7 +46,7 @@ var (
 // generating ACK service controller's apis/ contents
 func APIs(
 	g *generate.Generator,
-	templateBasePath string,
+	templateBasePaths []string,
 ) (*templateset.TemplateSet, error) {
 	enumDefs, err := g.GetEnumDefs()
 	if err != nil {
@@ -62,7 +62,7 @@ func APIs(
 	}
 
 	ts := templateset.New(
-		templateBasePath,
+		templateBasePaths,
 		apisIncludePaths,
 		apisCopyPaths,
 		apisFuncMap,

pkg/generate/ack/controller.go

@@ -112,15 +112,15 @@ var (
 // for generating ACK service controller implementations
 func Controller(
 	g *generate.Generator,
-	templateBasePath string,
+	templateBasePaths []string,
 ) (*templateset.TemplateSet, error) {
 	crds, err := g.GetCRDs()
 	if err != nil {
 		return nil, err
 	}
 
 	ts := templateset.New(
-		templateBasePath,
+		templateBasePaths,
 		controllerIncludePaths,
 		controllerCopyPaths,
 		controllerFuncMap,

pkg/generate/ack/release.go

@@ -47,7 +47,7 @@ var (
 // generating an ACK service controller release (Helm artifacts, etc)
 func Release(
 	g *generate.Generator,
-	templateBasePath string,
+	templateBasePaths []string,
 	// releaseVersion is the SemVer string describing the release that the Helm
 	// chart will install
 	releaseVersion string,
@@ -59,7 +59,7 @@ func Release(
 	serviceAccountName string,
 ) (*templateset.TemplateSet, error) {
 	ts := templateset.New(
-		templateBasePath,
+		templateBasePaths,
 		releaseIncludePaths,
 		releaseCopyPaths,
 		releaseFuncMap,

pkg/generate/crossplane/crossplane.go

@@ -27,18 +27,18 @@ import (
 
 var (
 	apisTemplatePaths = []string{
-		"apis/doc.go.tpl",
-		"apis/enums.go.tpl",
-		"apis/groupversion_info.go.tpl",
-		"apis/types.go.tpl",
+		"crossplane/apis/doc.go.tpl",
+		"crossplane/apis/enums.go.tpl",
+		"crossplane/apis/groupversion_info.go.tpl",
+		"crossplane/apis/types.go.tpl",
 	}
 	includePaths = []string{
-		"boilerplate.go.tpl",
-		"apis/enum_def.go.tpl",
-		"apis/type_def.go.tpl",
-		"pkg/sdk_find_read_one.go.tpl",
-		"pkg/sdk_find_read_many.go.tpl",
-		"pkg/sdk_find_get_attributes.go.tpl",
+		"crossplane/boilerplate.go.tpl",
+		"crossplane/apis/enum_def.go.tpl",
+		"crossplane/apis/type_def.go.tpl",
+		"crossplane/pkg/sdk_find_read_one.go.tpl",
+		"crossplane/pkg/sdk_find_read_many.go.tpl",
+		"crossplane/pkg/sdk_find_get_attributes.go.tpl",
 	}
 	copyPaths = []string{}
 	funcMap   = ttpl.FuncMap{
@@ -111,7 +111,7 @@ type templateCRDVars struct {
 // generating Crossplane API types and controller code for an AWS service API
 func Crossplane(
 	g *generate.Generator,
-	templateBasePath string,
+	templateBasePaths []string,
 ) (*templateset.TemplateSet, error) {
 	enumDefs, err := g.GetEnumDefs()
 	if err != nil {
@@ -127,7 +127,7 @@ func Crossplane(
 	}
 
 	ts := templateset.New(
-		templateBasePath,
+		templateBasePaths,
 		includePaths,
 		copyPaths,
 		funcMap,

pkg/generate/olm/olm.go

@@ -43,11 +43,11 @@ func BundleAssets(
 	commonMeta CommonMetadata,
 	serviceConfig ServiceConfig,
 	vers string,
-	templateBasePath string,
+	templateBasePaths []string,
 ) (*templateset.TemplateSet, error) {
 
 	ts := templateset.New(
-		templateBasePath,
+		templateBasePaths,
 		csvIncludePaths,
 		csvCopyPaths,
 		csvFuncMap,

pkg/generate/templateset/templateset.go

@@ -15,12 +15,29 @@ package templateset
 
 import (
 	"bytes"
+	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	ttpl "text/template"
+
+	"github.com/pkg/errors"
+)
+
+var (
+	// ErrTemplateNotFound is returned when a template path couldn't be located
+	// in any base search path
+	ErrTemplateNotFound    = errors.New("Template Not Found")
+	errMsgTemplateNotFound = "template %s not found in any base search path"
 )
 
+func errTemplateNotFound(templatePath string) error {
+	return errors.WithMessage(
+		ErrTemplateNotFound,
+		fmt.Sprintf(errMsgTemplateNotFound, templatePath),
+	)
+}
+
 // templateWithVars contains a template and the variables injected during execution
 type templateWithVars struct {
 	t *ttpl.Template
@@ -30,28 +47,30 @@ type templateWithVars struct {
 // TemplateSet contains a set of templates and copy files for a particular
 // target
 type TemplateSet struct {
-	basePath     string
-	includePaths []string
-	copyPaths    []string
-	templates    map[string]templateWithVars
-	funcMap      ttpl.FuncMap
-	executed     map[string]*bytes.Buffer
+	// baseSearchPaths is a set of directories from which templates will be
+	// searched
+	baseSearchPaths []string
+	includePaths    []string
+	copyPaths       []string
+	templates       map[string]templateWithVars
+	funcMap         ttpl.FuncMap
+	executed        map[string]*bytes.Buffer
 }
 
 // New returns a pointer to a TemplateSet
 func New(
-	templateBasePath string,
+	baseSearchPaths []string,
 	includePaths []string,
 	copyPaths []string,
 	funcMap ttpl.FuncMap,
 ) *TemplateSet {
 	return &TemplateSet{
-		basePath:     templateBasePath,
-		includePaths: includePaths,
-		copyPaths:    copyPaths,
-		funcMap:      funcMap,
-		templates:    map[string]templateWithVars{},
-		executed:     map[string]*bytes.Buffer{},
+		baseSearchPaths: baseSearchPaths,
+		includePaths:    includePaths,
+		copyPaths:       copyPaths,
+		funcMap:         funcMap,
+		templates:       map[string]templateWithVars{},
+		executed:        map[string]*bytes.Buffer{},
 	}
 }
 
@@ -61,27 +80,53 @@ func (ts *TemplateSet) Add(
 	templatePath string,
 	vars interface{},
 ) error {
-	path := filepath.Join(ts.basePath, templatePath)
-	tplContents, err := ioutil.ReadFile(path)
+	var foundPath string
+	for _, basePath := range ts.baseSearchPaths {
+		path := filepath.Join(basePath, templatePath)
+		if fileExists(path) {
+			foundPath = path
+			break
+		}
+	}
+
+	if foundPath == "" {
+		return errTemplateNotFound(templatePath)
+	}
+
+	tplContents, err := ioutil.ReadFile(foundPath)
 	if err != nil {
 		return err
 	}
-	t := ttpl.New(path)
+	t := ttpl.New(foundPath)
 	t = t.Funcs(ts.funcMap)
 	t, err = t.Parse(string(tplContents))
 	if err != nil {
 		return err
 	}
-	for _, includePath := range ts.includePaths {
-		tplPath := filepath.Join(ts.basePath, includePath)
-		if t, err = includeTemplate(t, tplPath); err != nil {
-			return err
-		}
+	if err = ts.joinIncludes(t); err != nil {
+		return err
 	}
 	ts.templates[outPath] = templateWithVars{t, vars}
 	return nil
 }
 
+// joinIncludes adds all include templates to the supplied template
+func (ts *TemplateSet) joinIncludes(t *ttpl.Template) error {
+	var err error
+	for _, basePath := range ts.baseSearchPaths {
+		for _, includePath := range ts.includePaths {
+			tplPath := filepath.Join(basePath, includePath)
+			if !fileExists(tplPath) {
+				continue
+			}
+			if t, err = includeTemplate(t, tplPath); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 // Execute runs all of the template and copy files in our TemplateSet and
 // returns whether any error occurred executing any of the templates. Once
 // Execute() is run, `TemplateSet.Executed()` can be used to iterate over a set
@@ -94,13 +139,18 @@ func (ts *TemplateSet) Execute() error {
 		}
 		ts.executed[path] = &b
 	}
-	for _, path := range ts.copyPaths {
-		copyPath := filepath.Join(ts.basePath, path)
-		b, err := byteBufferFromFile(copyPath)
-		if err != nil {
-			return err
+	for _, basePath := range ts.baseSearchPaths {
+		for _, path := range ts.copyPaths {
+			copyPath := filepath.Join(basePath, path)
+			if !fileExists(copyPath) {
+				continue
+			}
+			b, err := byteBufferFromFile(copyPath)
+			if err != nil {
+				return err
+			}
+			ts.executed[path] = b
 		}
-		ts.executed[path] = b
 	}
 	return nil
 }
@@ -144,3 +194,9 @@ func includeTemplate(t *ttpl.Template, tplPath string) (*ttpl.Template, error) {
 	}
 	return t, nil
 }
+
+// fileExists returns tTrue if the supplied file path exists, false otherwise
+func fileExists(path string) bool {
+	_, err := os.Stat(path)
+	return !os.IsNotExist(err)
+}