bug openapi: fix path params parsing (#155)

Author: chebykinn

go.mod

@@ -62,6 +62,7 @@ require (
 	github.com/spf13/afero v1.8.0 // indirect
 	github.com/spf13/cast v1.4.1 // indirect
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
+	github.com/stretchr/objx v0.4.0 // indirect
 	github.com/subosito/gotenv v1.2.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.0 // indirect
 	go.uber.org/atomic v1.9.0 // indirect

go.sum

@@ -413,6 +413,7 @@ github.com/spf13/viper v1.10.1/go.mod h1:IGlFPqhNAPKRxohIzWpI5QEy4kuI7tcl5WvR+8q
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.2.0/go.mod h1:qt09Ya8vawLte6SNmTgCsAVtYtaKzEcn8ATUoHMkEqE=
+github.com/stretchr/objx v0.4.0 h1:M2gUjqZET1qApGOWNSnZ49BAIMX4F/1plDv3+l31EJ4=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

pkg/generator/lib/endpoints/env_helper.go

@@ -44,3 +44,18 @@ func SnakeCaseToCamelCase(inputUnderScoreStr string, capitalize bool) (camelCase
 	}
 	return
 }
+
+func CamelCaseToSnakeCase(inputCamelCaseStr string) string {
+	var outputSnakeCaseStr string
+	for i, r := range inputCamelCaseStr {
+		if unicode.IsUpper(r) {
+			if i > 0 && unicode.IsLower(rune(inputCamelCaseStr[i-1])) {
+				outputSnakeCaseStr += "_"
+			}
+			outputSnakeCaseStr += string(unicode.ToLower(r))
+		} else {
+			outputSnakeCaseStr += string(r)
+		}
+	}
+	return outputSnakeCaseStr
+}

pkg/generator/steps/openapi/processors/golang.go

@@ -98,8 +98,7 @@ func (p *goPostProcessor) PopulateServerHandlers(ctx *gencontext.GenContext, pat
 	}
 	pathsSet := map[string]string{}
 	for _, path := range paths {
-		path = strings.ReplaceAll(path, "{", "")
-		path = strings.ReplaceAll(path, "}", "")
+		ctx.Logger.Infof("pre path: %s", path)
 		pathsSet[toAPIFilename(path)] = path
 	}
 	ctx.Logger.Infof("paths: %v", pathsSet)
@@ -218,22 +217,17 @@ func isReservedFilename(name string) bool {
 }
 
 var (
-	capitalLetterPattern = regexp.MustCompile(`([A-Z]+)([A-Z][a-z][a-z]+)`)
-	lowercasePattern     = regexp.MustCompile(`([a-z\d])([A-Z])`)
 	pkgSeparatorPattern  = regexp.MustCompile(`\.`)
 	dollarPattern        = regexp.MustCompile(`\$`)
 )
 
 // taken from openapi-generator
 func underscore(word string) string {
-	replacementPattern := "$1_$2"
 	// Replace package separator with slash.
-	result := pkgSeparatorPattern.ReplaceAllString(word, "/")
+	result := pkgSeparatorPattern.ReplaceAllString(word, "_")
 	// Replace $ with two underscores for inner classes.
 	result = dollarPattern.ReplaceAllString(result, "__")
-	// Replace capital letter with _ plus lowercase letter.
-	result = capitalLetterPattern.ReplaceAllString(result, replacementPattern)
-	result = lowercasePattern.ReplaceAllString(result, replacementPattern)
+	result = endpoints.CamelCaseToSnakeCase(result)
 	result = strings.ReplaceAll(result, "-", "_")
 	// replace space with underscore
 	result = strings.ReplaceAll(result, " ", "_")
@@ -246,7 +240,9 @@ func toAPIFilename(name string) string {
 	// NOTE: openapi-generator transforms tag to camelCase, we don't do that here
 	// we just remove slashes from path and then use openapi-generator logic
 	// to convert this path to filename.
-	api := strings.TrimPrefix(name, "/")
+	api := strings.ReplaceAll(name, "{", "")
+	api = strings.ReplaceAll(api, "}", "")
+	api = strings.TrimPrefix(api, "/")
 	api = strings.TrimSuffix(api, "/")
 	api = strings.ReplaceAll(api, "/", "_")
 	// replace - with _ e.g. created-at => created_at

pkg/generator/steps/openapi/processors/string_utils_test.go

@@ -0,0 +1,17 @@
+package processors
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestToApiFilename(t *testing.T) {
+	assert.Equal(t, "api_path_to_api", toAPIFilename("/path/to/api"))
+	assert.Equal(t, "api_path_to_api", toAPIFilename("/path/to/api/"))
+	assert.Equal(t, "api_path_to_api_minus", toAPIFilename("/path/to/api-minus/"))
+	assert.Equal(t, "api_path_to_api_param_test_other", toAPIFilename("/path/to/api/{param}.{test}/{other}"))
+
+	// reserved filename
+	assert.Equal(t, "api_api_v1_test_", toAPIFilename("/api/v1/test"))
+}