Repository: deepmap/oapi-codegen (go)

Issue:
Respect initialisms for schema generation
Per the [Go code review guide](https://github.com/golang/go/wiki/CodeReviewComments#initialisms), initialisms like ID, DB, etc. should have consistent casing like `id` or `ID`. However, the schema generation functionality is just converting the properties to UpperCamelCase and disregarding this rule, which produces structs with fields like `Id` and `Db`.

The culprit seems to be that [schema.go](https://github.com/deepmap/oapi-codegen/blob/546b69d513f7cc98da2eeee46c2aaf43ad895e35/pkg/codegen/utils.go#L524) calls [ToCamelCase](https://github.com/deepmap/oapi-codegen/blob/546b69d513f7cc98da2eeee46c2aaf43ad895e35/pkg/codegen/utils.go#L59), a homegrown case converter. Packages like [iancoleman/strcase](https://github.com/iancoleman/strcase#custom-acronyms-for-tocamel--tolowercamel) support custom acronyms so that users can specify these initialism overrides. We don't necessarily need to import this new package but it's a good illustration of how this might be implemented.

One option is to maintain the current behavior but add a new configuration flag `-initialisms` with values like `ID,HTTP,DB` that would override those parts of the property name.

Another option is to create a new property extension that would allow users to override the struct field name in the Open API definition, e.g. `x-oapi-codegen-name`. Maybe something similar for overriding the json tag as well if necessary. The risk with this approach is that we will alienate people that are using an OpenAPI doc that they do not own and therefore cannot modify to add these extended properties.

Some test cases:
- `dbName`
  - Expected: _DBName string \`json:"dbName"\`_
  - Actual:  _DbName string \`json:"dbName"\`_
- `id`
  - Expected: _ID string \`json:"id"\`_
  - Actual: _Id string \`json:"id"\`_
- `someHttpThing`
  - Expected: _SomeHTTPThing string \`json:"someHttpThing"\`_ (json tag is not changed)
  - Actual: _SomeHttpThing string \`json:"someHttpThing"\`_
- `some_http_thing`
  - Expected: _SomeHTTPThing string \`json:"some_http_thing"\`_
  - Actual: _SomeHttpThing string \`json:"some_http_thing"\`_



Pull request description:
Add initialism-overrides flag
Fixes #454  and #573
The PR still announced it needed to be implemented as a command option, so I reworked the implementation.

Patch:
diff --git a/cmd/oapi-codegen/oapi-codegen.go b/cmd/oapi-codegen/oapi-codegen.go
index 7d9f2cc..ea9e008 100644
--- a/cmd/oapi-codegen/oapi-codegen.go
+++ b/cmd/oapi-codegen/oapi-codegen.go
@@ -53,6 +53,7 @@ var (
 	flagExcludeSchemas     string
 	flagResponseTypeSuffix string
 	flagAliasTypes         bool
+	flagInitalismOverrides bool
 )
 
 type configuration struct {
@@ -98,6 +99,7 @@ func main() {
 	flag.StringVar(&flagExcludeSchemas, "exclude-schemas", "", "A comma separated list of schemas which must be excluded from generation")
 	flag.StringVar(&flagResponseTypeSuffix, "response-type-suffix", "", "the suffix used for responses types")
 	flag.BoolVar(&flagAliasTypes, "alias-types", false, "Alias type declarations of possible")
+	flag.BoolVar(&flagInitalismOverrides, "initialism-overrides", false, "Use initialism overrides")
 
 	flag.Parse()
 
@@ -396,6 +398,8 @@ func updateConfigFromFlags(cfg *configuration) error {
 		cfg.OutputFile = flagOutputFile
 	}
 
+	cfg.OutputOptions.InitialismOverrides = flagInitalismOverrides
+
 	return nil
 }
 
diff --git a/examples/petstore-expanded/strict/api/petstore-server.gen.go b/examples/petstore-expanded/strict/api/petstore-server.gen.go
index cd9352a..822dee7 100644
--- a/examples/petstore-expanded/strict/api/petstore-server.gen.go
+++ b/examples/petstore-expanded/strict/api/petstore-server.gen.go
@@ -408,9 +408,8 @@ type StrictServerInterface interface {
 	FindPetByID(ctx context.Context, request FindPetByIDRequestObject) (FindPetByIDResponseObject, error)
 }
 
-type StrictHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictHttpHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictHttpMiddlewareFunc
 
 type StrictHTTPServerOptions struct {
 	RequestErrorHandlerFunc  func(w http.ResponseWriter, r *http.Request, err error)
diff --git a/go.mod b/go.mod
index e3364ea..3f1ea19 100644
--- a/go.mod
+++ b/go.mod
@@ -2,7 +2,7 @@ module github.com/deepmap/oapi-codegen
 
 require (
 	github.com/apapsch/go-jsonmerge/v2 v2.0.0
-	github.com/getkin/kin-openapi v0.114.0
+	github.com/getkin/kin-openapi v0.115.0
 	github.com/gin-gonic/gin v1.9.0
 	github.com/go-chi/chi/v5 v5.0.8
 	github.com/golangci/lint-1 v0.0.0-20181222135242-d2cdd8c08219
@@ -12,7 +12,7 @@ require (
 	github.com/lestrrat-go/jwx v1.2.25
 	github.com/matryer/moq v0.3.1
 	github.com/stretchr/testify v1.8.2
-	golang.org/x/text v0.8.0
+	golang.org/x/text v0.9.0
 	golang.org/x/tools v0.7.0
 	gopkg.in/yaml.v2 v2.4.0
 )
diff --git a/go.sum b/go.sum
index 5e5310b..6cf490a 100644
--- a/go.sum
+++ b/go.sum
@@ -16,8 +16,8 @@ github.com/decred/dcrd/crypto/blake256 v1.0.0/go.mod h1:sQl2p6Y26YV+ZOcSTP6thNdn
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.0-20210816181553-5444fa50b93d/go.mod h1:tmAIfUFEirG/Y8jhZ9M+h36obRZAk/1fcSpXwAVlfqE=
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 h1:YLtO71vCjJRCBcrPMtQ9nqBsqpA1m5sE92cU+pd5Mcc=
 github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1/go.mod h1:hyedUtir6IdtD/7lIxGeCxkaw7y45JueMRL4DIyJDKs=
-github.com/getkin/kin-openapi v0.114.0 h1:ar7QiJpDdlR+zSyPjrLf8mNnpoFP/lI90XcywMCFNe8=
-github.com/getkin/kin-openapi v0.114.0/go.mod h1:l5e9PaFUo9fyLJCPGQeXI2ML8c3P8BHOEV2VaAVf/pc=
+github.com/getkin/kin-openapi v0.115.0 h1:c8WHRLVY3G8m9jQTy0/DnIuljgRwTCB5twZytQS4JyU=
+github.com/getkin/kin-openapi v0.115.0/go.mod h1:l5e9PaFUo9fyLJCPGQeXI2ML8c3P8BHOEV2VaAVf/pc=
 github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=
 github.com/gin-contrib/sse v0.1.0/go.mod h1:RHrZQHXnP2xjPF+u1gW/2HnVO7nvIa9PG3Gm+fLHvGI=
 github.com/gin-gonic/gin v1.9.0 h1:OjyFBKICoexlu99ctXNR2gg+c5pKrKMuyjgARg9qeY8=
@@ -164,8 +164,8 @@ golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.8.0 h1:57P1ETyNKtuIjB4SRd15iJxuhj8Gc416Y78H3qgMh68=
-golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/text v0.9.0 h1:2sjJmO8cDvYveuX97RDLsxlyUxLl+GHoLxBiRdHllBE=
+golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
 golang.org/x/time v0.3.0 h1:rg5rLMjNzMS1RkNLzCG38eapWhnYLFYXDXj2gOlr8j4=
 golang.org/x/time v0.3.0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
diff --git a/pkg/codegen/codegen.go b/pkg/codegen/codegen.go
index 956d589..70dca56 100644
--- a/pkg/codegen/codegen.go
+++ b/pkg/codegen/codegen.go
@@ -138,7 +138,7 @@ func Generate(spec *openapi3.T, opts Configuration) (string, error) {
 		}
 	}
 
-	ops, err := OperationDefinitions(spec)
+	ops, err := OperationDefinitions(spec, opts.OutputOptions.InitialismOverrides)
 	if err != nil {
 		return "", fmt.Errorf("error creating operation definitions: %w", err)
 	}
diff --git a/pkg/codegen/configuration.go b/pkg/codegen/configuration.go
index afa4fc5..8d7f2e6 100644
--- a/pkg/codegen/configuration.go
+++ b/pkg/codegen/configuration.go
@@ -84,9 +84,10 @@ type OutputOptions struct {
 	ExcludeTags   []string          `yaml:"exclude-tags,omitempty"`   // Exclude operations that have one of these tags. Ignored when empty.
 	UserTemplates map[string]string `yaml:"user-templates,omitempty"` // Override built-in templates from user-provided files
 
-	ExcludeSchemas     []string `yaml:"exclude-schemas,omitempty"`      // Exclude from generation schemas with given names. Ignored when empty.
-	ResponseTypeSuffix string   `yaml:"response-type-suffix,omitempty"` // The suffix used for responses types
-	ClientTypeName     string   `yaml:"client-type-name,omitempty"`     // Override the default generated client type with the value
+	ExcludeSchemas      []string `yaml:"exclude-schemas,omitempty"`      // Exclude from generation schemas with given names. Ignored when empty.
+	ResponseTypeSuffix  string   `yaml:"response-type-suffix,omitempty"` // The suffix used for responses types
+	ClientTypeName      string   `yaml:"client-type-name,omitempty"`     // Override the default generated client type with the value
+	InitialismOverrides bool     `yaml:"initialism-overrides,omitempty"` // Whether to use the initialism overrides
 }
 
 // UpdateDefaults sets reasonable default values for unset fields in Configuration
diff --git a/pkg/codegen/operations.go b/pkg/codegen/operations.go
index 28b991f..048836f 100644
--- a/pkg/codegen/operations.go
+++ b/pkg/codegen/operations.go
@@ -483,9 +483,16 @@ func FilterParameterDefinitionByType(params []ParameterDefinition, in string) []
 }
 
 // OperationDefinitions returns all operations for a swagger definition.
-func OperationDefinitions(swagger *openapi3.T) ([]OperationDefinition, error) {
+func OperationDefinitions(swagger *openapi3.T, initialismOverrides bool) ([]OperationDefinition, error) {
 	var operations []OperationDefinition
 
+	var toCamelCaseFunc func(string) string
+	if initialismOverrides {
+		toCamelCaseFunc = ToCamelCaseWithInitialism
+	} else {
+		toCamelCaseFunc = ToCamelCase
+	}
+
 	for _, requestPath := range SortedPathsKeys(swagger.Paths) {
 		pathItem := swagger.Paths[requestPath]
 		// These are parameters defined for all methods on a given path. They
@@ -505,13 +512,13 @@ func OperationDefinitions(swagger *openapi3.T) ([]OperationDefinition, error) {
 			}
 			// We rely on OperationID to generate function names, it's required
 			if op.OperationID == "" {
-				op.OperationID, err = generateDefaultOperationID(opName, requestPath)
+				op.OperationID, err = generateDefaultOperationID(opName, requestPath, toCamelCaseFunc)
 				if err != nil {
 					return nil, fmt.Errorf("error generating default OperationID for %s/%s: %s",
 						opName, requestPath, err)
 				}
 			} else {
-				op.OperationID = ToCamelCase(op.OperationID)
+				op.OperationID = toCamelCaseFunc(op.OperationID)
 			}
 			op.OperationID = typeNamePrefix(op.OperationID) + op.OperationID
 
@@ -550,7 +557,7 @@ func OperationDefinitions(swagger *openapi3.T) ([]OperationDefinition, error) {
 				HeaderParams: FilterParameterDefinitionByType(allParams, "header"),
 				QueryParams:  FilterParameterDefinitionByType(allParams, "query"),
 				CookieParams: FilterParameterDefinitionByType(allParams, "cookie"),
-				OperationId:  ToCamelCase(op.OperationID),
+				OperationId:  toCamelCaseFunc(op.OperationID),
 				// Replace newlines in summary.
 				Summary:         op.Summary,
 				Method:          opName,
@@ -588,7 +595,7 @@ func OperationDefinitions(swagger *openapi3.T) ([]OperationDefinition, error) {
 	return operations, nil
 }
 
-func generateDefaultOperationID(opName string, requestPath string) (string, error) {
+func generateDefaultOperationID(opName string, requestPath string, toCamelCaseFunc func(string) string) (string, error) {
 	var operationId = strings.ToLower(opName)
 
 	if opName == "" {
@@ -605,7 +612,7 @@ func generateDefaultOperationID(opName string, requestPath string) (string, erro
 		}
 	}
 
-	return ToCamelCase(operationId), nil
+	return toCamelCaseFunc(operationId), nil
 }
 
 // GenerateBodyDefinitions turns the Swagger body definitions into a list of our body
diff --git a/pkg/codegen/schema.go b/pkg/codegen/schema.go
index 457e102..e9fccbf 100644
--- a/pkg/codegen/schema.go
+++ b/pkg/codegen/schema.go
@@ -638,17 +638,20 @@ func GenFieldsFromProperties(props []Property) []string {
 
 		field += fmt.Sprintf("    %s %s", goFieldName, p.GoTypeDef())
 
+		omitEmpty := !p.Nullable &&
+			(!p.Required || p.ReadOnly || p.WriteOnly) &&
+			(!p.Required || !p.ReadOnly || !globalState.options.Compatibility.DisableRequiredReadOnlyAsPointer)
+
 		// Support x-omitempty
-		overrideOmitEmpty := true
-		if _, ok := p.Extensions[extPropOmitEmpty]; ok {
-			if extOmitEmpty, err := extParseOmitEmpty(p.Extensions[extPropOmitEmpty]); err == nil {
-				overrideOmitEmpty = extOmitEmpty
+		if extOmitEmptyValue, ok := p.Extensions[extPropOmitEmpty]; ok {
+			if extOmitEmpty, err := extParseOmitEmpty(extOmitEmptyValue); err == nil {
+				omitEmpty = extOmitEmpty
 			}
 		}
 
 		fieldTags := make(map[string]string)
 
-		if (p.Required && !p.ReadOnly && !p.WriteOnly) || p.Nullable || !overrideOmitEmpty || (p.Required && p.ReadOnly && globalState.options.Compatibility.DisableRequiredReadOnlyAsPointer) {
+		if !omitEmpty {
 			fieldTags["json"] = p.JsonFieldName
 			if p.NeedsFormTag {
 				fieldTags["form"] = p.JsonFieldName
diff --git a/pkg/codegen/templates/strict/strict-echo.tmpl b/pkg/codegen/templates/strict/strict-echo.tmpl
index 4bd6aec..86def37 100644
--- a/pkg/codegen/templates/strict/strict-echo.tmpl
+++ b/pkg/codegen/templates/strict/strict-echo.tmpl
@@ -1,6 +1,5 @@
-type StrictHandlerFunc func(ctx echo.Context, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictEchoHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictEchoMiddlewareFunc
 
 func NewStrictHandler(ssi StrictServerInterface, middlewares []StrictMiddlewareFunc) ServerInterface {
     return &strictHandler{ssi: ssi, middlewares: middlewares}
diff --git a/pkg/codegen/templates/strict/strict-gin.tmpl b/pkg/codegen/templates/strict/strict-gin.tmpl
index 9622fb2..23d8f0b 100644
--- a/pkg/codegen/templates/strict/strict-gin.tmpl
+++ b/pkg/codegen/templates/strict/strict-gin.tmpl
@@ -1,6 +1,5 @@
-type StrictHandlerFunc func(ctx *gin.Context, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictGinHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictGinMiddlewareFunc
 
 func NewStrictHandler(ssi StrictServerInterface, middlewares []StrictMiddlewareFunc) ServerInterface {
     return &strictHandler{ssi: ssi, middlewares: middlewares}
diff --git a/pkg/codegen/templates/strict/strict-http.tmpl b/pkg/codegen/templates/strict/strict-http.tmpl
index d04503d..b16ed1d 100644
--- a/pkg/codegen/templates/strict/strict-http.tmpl
+++ b/pkg/codegen/templates/strict/strict-http.tmpl
@@ -1,6 +1,5 @@
-type StrictHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictHttpHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictHttpMiddlewareFunc
 
 type StrictHTTPServerOptions struct {
     RequestErrorHandlerFunc  func(w http.ResponseWriter, r *http.Request, err error)
diff --git a/pkg/codegen/utils.go b/pkg/codegen/utils.go
index c386cd3..ee51af6 100644
--- a/pkg/codegen/utils.go
+++ b/pkg/codegen/utils.go
@@ -160,6 +160,24 @@ func ToCamelCase(str string) string {
 	return n
 }
 
+func ToCamelCaseWithInitialism(str string) string {
+	return replaceInitialism(ToCamelCase(str))
+}
+
+func replaceInitialism(s string) string {
+	// These strings do not apply CamelCase
+	// Do not do CamelCase when these characters match when the preceding character is lowercase
+	// ["Acl", "Api", "Ascii", "Cpu", "Css", "Dns", "Eof", "Guid", "Html", "Http", "Https", "Id", "Ip", "Json", "Qps", "Ram", "Rpc", "Sla", "Smtp", "Sql", "Ssh", "Tcp", "Tls", "Ttl", "Udp", "Ui", "Gid", "Uid", "Uuid", "Uri", "Url", "Utf8", "Vm", "Xml", "Xmpp", "Xsrf", "Xss", "Sip", "Rtp", "Amqp", "Db", "Ts"]
+	targetWordRegex := regexp.MustCompile(`(?i)(Acl|Api|Ascii|Cpu|Css|Dns|Eof|Guid|Html|Http|Https|Id|Ip|Json|Qps|Ram|Rpc|Sla|Smtp|Sql|Ssh|Tcp|Tls|Ttl|Udp|Ui|Gid|Uid|Uuid|Uri|Url|Utf8|Vm|Xml|Xmpp|Xsrf|Xss|Sip|Rtp|Amqp|Db|Ts)`)
+	return targetWordRegex.ReplaceAllStringFunc(s, func(s string) string {
+		// If the preceding character is lowercase, do not do CamelCase
+		if unicode.IsLower(rune(s[0])) {
+			return s
+		}
+		return strings.ToUpper(s)
+	})
+}
+
 // SortedSchemaKeys returns the keys of the given SchemaRef dictionary in sorted
 // order, since Golang scrambles dictionary keys
 func SortedSchemaKeys(dict map[string]*openapi3.SchemaRef) []string {
diff --git a/pkg/runtime/strictmiddleware.go b/pkg/runtime/strictmiddleware.go
new file mode 100644
index 0000000..fac240e
--- /dev/null
+++ b/pkg/runtime/strictmiddleware.go
@@ -0,0 +1,21 @@
+package runtime
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"github.com/labstack/echo/v4"
+)
+
+type StrictEchoHandlerFunc func(ctx echo.Context, request interface{}) (response interface{}, err error)
+
+type StrictEchoMiddlewareFunc func(f StrictEchoHandlerFunc, operationID string) StrictEchoHandlerFunc
+
+type StrictHttpHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, request interface{}) (response interface{}, err error)
+
+type StrictHttpMiddlewareFunc func(f StrictHttpHandlerFunc, operationID string) StrictHttpHandlerFunc
+
+type StrictGinHandlerFunc func(ctx *gin.Context, request interface{}) (response interface{}, err error)
+
+type StrictGinMiddlewareFunc func(f StrictGinHandlerFunc, operationID string) StrictGinHandlerFunc


Test patch:
diff --git a/internal/test/issues/issue-removed-external-ref/gen/spec_base/issue.gen.go b/internal/test/issues/issue-removed-external-ref/gen/spec_base/issue.gen.go
index 09e8df3..69766e1 100644
--- a/internal/test/issues/issue-removed-external-ref/gen/spec_base/issue.gen.go
+++ b/internal/test/issues/issue-removed-external-ref/gen/spec_base/issue.gen.go
@@ -10,6 +10,7 @@ import (
 	"net/http"
 
 	externalRef0 "github.com/deepmap/oapi-codegen/internal/test/issues/issue-removed-external-ref/gen/spec_ext"
+	"github.com/deepmap/oapi-codegen/pkg/runtime"
 	"github.com/go-chi/chi/v5"
 )
 
@@ -244,9 +245,8 @@ type StrictServerInterface interface {
 	PostNoTrouble(ctx context.Context, request PostNoTroubleRequestObject) (PostNoTroubleResponseObject, error)
 }
 
-type StrictHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictHttpHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictHttpMiddlewareFunc
 
 type StrictHTTPServerOptions struct {
 	RequestErrorHandlerFunc  func(w http.ResponseWriter, r *http.Request, err error)
diff --git a/internal/test/issues/issue-removed-external-ref/gen/spec_ext/issue.gen.go b/internal/test/issues/issue-removed-external-ref/gen/spec_ext/issue.gen.go
index 21222f8..ed5a474 100644
--- a/internal/test/issues/issue-removed-external-ref/gen/spec_ext/issue.gen.go
+++ b/internal/test/issues/issue-removed-external-ref/gen/spec_ext/issue.gen.go
@@ -4,10 +4,10 @@
 package spec_ext
 
 import (
-	"context"
 	"fmt"
 	"net/http"
 
+	"github.com/deepmap/oapi-codegen/pkg/runtime"
 	"github.com/go-chi/chi/v5"
 )
 
@@ -161,9 +161,8 @@ type PascalJSONResponse PascalSchema
 type StrictServerInterface interface {
 }
 
-type StrictHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictHttpHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictHttpMiddlewareFunc
 
 type StrictHTTPServerOptions struct {
 	RequestErrorHandlerFunc  func(w http.ResponseWriter, r *http.Request, err error)
diff --git a/internal/test/strict-server/chi/server.gen.go b/internal/test/strict-server/chi/server.gen.go
index 236277c..b3904b5 100644
--- a/internal/test/strict-server/chi/server.gen.go
+++ b/internal/test/strict-server/chi/server.gen.go
@@ -892,9 +892,8 @@ type StrictServerInterface interface {
 	HeadersExample(ctx context.Context, request HeadersExampleRequestObject) (HeadersExampleResponseObject, error)
 }
 
-type StrictHandlerFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictHttpHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictHttpMiddlewareFunc
 
 type StrictHTTPServerOptions struct {
 	RequestErrorHandlerFunc  func(w http.ResponseWriter, r *http.Request, err error)
diff --git a/internal/test/strict-server/echo/server.gen.go b/internal/test/strict-server/echo/server.gen.go
index ebd374b..0912230 100644
--- a/internal/test/strict-server/echo/server.gen.go
+++ b/internal/test/strict-server/echo/server.gen.go
@@ -706,9 +706,8 @@ type StrictServerInterface interface {
 	HeadersExample(ctx context.Context, request HeadersExampleRequestObject) (HeadersExampleResponseObject, error)
 }
 
-type StrictHandlerFunc func(ctx echo.Context, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictEchoHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictEchoMiddlewareFunc
 
 func NewStrictHandler(ssi StrictServerInterface, middlewares []StrictMiddlewareFunc) ServerInterface {
 	return &strictHandler{ssi: ssi, middlewares: middlewares}
diff --git a/internal/test/strict-server/gin/server.gen.go b/internal/test/strict-server/gin/server.gen.go
index 618db70..78b68e5 100644
--- a/internal/test/strict-server/gin/server.gen.go
+++ b/internal/test/strict-server/gin/server.gen.go
@@ -763,9 +763,8 @@ type StrictServerInterface interface {
 	HeadersExample(ctx context.Context, request HeadersExampleRequestObject) (HeadersExampleResponseObject, error)
 }
 
-type StrictHandlerFunc func(ctx *gin.Context, args interface{}) (interface{}, error)
-
-type StrictMiddlewareFunc func(f StrictHandlerFunc, operationID string) StrictHandlerFunc
+type StrictHandlerFunc = runtime.StrictGinHandlerFunc
+type StrictMiddlewareFunc = runtime.StrictGinMiddlewareFunc
 
 func NewStrictHandler(ssi StrictServerInterface, middlewares []StrictMiddlewareFunc) ServerInterface {
 	return &strictHandler{ssi: ssi, middlewares: middlewares}
diff --git a/pkg/codegen/operations_test.go b/pkg/codegen/operations_test.go
index 0eff03e..77a54a8 100644
--- a/pkg/codegen/operations_test.go
+++ b/pkg/codegen/operations_test.go
@@ -131,7 +131,7 @@ func TestGenerateDefaultOperationID(t *testing.T) {
 	}
 
 	for _, test := range suite {
-		got, err := generateDefaultOperationID(test.op, test.path)
+		got, err := generateDefaultOperationID(test.op, test.path, ToCamelCase)
 		if err != nil {
 			if !test.wantErr {
 				t.Fatalf("did not expected error but got %v", err)
diff --git a/pkg/codegen/utils_test.go b/pkg/codegen/utils_test.go
index 32708f0..85b6031 100644
--- a/pkg/codegen/utils_test.go
+++ b/pkg/codegen/utils_test.go
@@ -446,3 +446,45 @@ func TestRefPathToObjName(t *testing.T) {
 		assert.Equal(t, want, RefPathToObjName(in))
 	}
 }
+
+func Test_replaceInitialisms(t *testing.T) {
+	type args struct {
+		s string
+	}
+	tests := []struct {
+		name string
+		args args
+		want string
+	}{
+		{
+			name: "empty string",
+			args: args{s: ""},
+			want: "",
+		},
+		{
+			name: "no initialism",
+			args: args{s: "foo"},
+			want: "foo",
+		},
+		{
+			name: "one initialism",
+			args: args{s: "fooId"},
+			want: "fooID",
+		},
+		{
+			name: "two initialism",
+			args: args{s: "fooIdBarApi"},
+			want: "fooIDBarAPI",
+		},
+		{
+			name: "already initialism",
+			args: args{s: "fooIDBarAPI"},
+			want: "fooIDBarAPI",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equalf(t, tt.want, replaceInitialism(tt.args.s), "replaceInitialism(%v)", tt.args.s)
+		})
+	}
+}