package codegen

import (

"errors"

"fmt"

"reflect"

)

type AdditionalImport struct {

Alias string `yaml:"alias,omitempty"`

Package string `yaml:"package"`

}

// Configuration defines code generation customizations

type Configuration struct {

// PackageName to generate the code under

PackageName string `yaml:"package"`

// Generate specifies which supported output formats to generate

Generate GenerateOptions `yaml:"generate,omitempty"`

// CompatibilityOptions specifies backward compatibility settings for the code generator

Compatibility CompatibilityOptions `yaml:"compatibility,omitempty"`

// OutputOptions are used to modify the output code in some way.

OutputOptions OutputOptions `yaml:"output-options,omitempty"`

// ImportMapping specifies the golang package path for each external reference

ImportMapping map[string]string `yaml:"import-mapping,omitempty"`

// AdditionalImports defines any additional Go imports to add to the generated code

AdditionalImports []AdditionalImport `yaml:"additional-imports,omitempty"`

// NoVCSVersionOverride allows overriding the version of the application for cases where no Version Control System (VCS) is available when building, for instance when using a Nix derivation.

// See documentation for how to use it in examples/no-vcs-version-override/README.md

NoVCSVersionOverride *string `yaml:"-"`

}

// Validate checks whether Configuration represent a valid configuration

func (o Configuration) Validate() error {

if o.PackageName == "" {

return errors.New("package name must be specified")

}

// Only one server type should be specified at a time.

nServers := 0

if o.Generate.IrisServer {

nServers++

}

if o.Generate.ChiServer {

nServers++

}

if o.Generate.FiberServer {

nServers++

}

if o.Generate.EchoServer {

nServers++

}

if o.Generate.Echo5Server {

nServers++

}

if o.Generate.GorillaServer {

nServers++

}

if o.Generate.StdHTTPServer {

nServers++

}

if o.Generate.GinServer {

nServers++

}

if nServers > 1 {

return errors.New("only one server type is supported at a time")

}

var errs []error

if problems := o.Generate.Validate(); problems != nil {

for k, v := range problems {

errs = append(errs, fmt.Errorf("`generate` configuration for %v was incorrect: %v", k, v))

}

}

if problems := o.Compatibility.Validate(); problems != nil {

for k, v := range problems {

errs = append(errs, fmt.Errorf("`compatibility-options` configuration for %v was incorrect: %v", k, v))

}

}

if problems := o.OutputOptions.Validate(); problems != nil {

for k, v := range problems {

errs = append(errs, fmt.Errorf("`output-options` configuration for %v was incorrect: %v", k, v))

}

}

err := errors.Join(errs...)

if err != nil {

return fmt.Errorf("failed to validate configuration: %w", err)

}

return nil

}

// UpdateDefaults sets reasonable default values for unset fields in Configuration

func (o Configuration) UpdateDefaults() Configuration {

if reflect.ValueOf(o.Generate).IsZero() {

o.Generate = GenerateOptions{

EchoServer: true,

Models: true,

EmbeddedSpec: true,

}

}

return o

}

// GenerateOptions specifies which supported output formats to generate.

type GenerateOptions struct {

// IrisServer specifies whether to generate iris server boilerplate

IrisServer bool `yaml:"iris-server,omitempty"`

// ChiServer specifies whether to generate chi server boilerplate

ChiServer bool `yaml:"chi-server,omitempty"`

// FiberServer specifies whether to generate fiber server boilerplate

FiberServer bool `yaml:"fiber-server,omitempty"`

// EchoServer specifies whether to generate echo server boilerplate

EchoServer bool `yaml:"echo-server,omitempty"`

// Echo5Server specifies whether to generate echo v5 server boilerplate

Echo5Server bool `yaml:"echo5-server,omitempty"`

// GinServer specifies whether to generate gin server boilerplate

GinServer bool `yaml:"gin-server,omitempty"`

// GorillaServer specifies whether to generate Gorilla server boilerplate

GorillaServer bool `yaml:"gorilla-server,omitempty"`

// StdHTTPServer specifies whether to generate stdlib http server boilerplate

StdHTTPServer bool `yaml:"std-http-server,omitempty"`

// Strict specifies whether to generate strict server wrapper

Strict bool `yaml:"strict-server,omitempty"`

// Client specifies whether to generate client boilerplate

Client bool `yaml:"client,omitempty"`

// Models specifies whether to generate type definitions

Models bool `yaml:"models,omitempty"`

// EmbeddedSpec indicates whether to embed the swagger spec in the generated code

EmbeddedSpec bool `yaml:"embedded-spec,omitempty"`

// ServerURLs generates types for the `Server` definitions' URLs, instead of needing to provide your own values

ServerURLs bool `yaml:"server-urls,omitempty"`

}

// RouterImports returns the framework-specific and strict middleware imports

// needed based on which server type is selected.

func (g GenerateOptions) RouterImports() []AdditionalImport {

var imports []AdditionalImport

switch {

case g.EchoServer:

imports = append(imports, AdditionalImport{Package: "github.com/labstack/echo/v4"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictecho", Package: "github.com/oapi-codegen/runtime/strictmiddleware/echo"})

}

case g.Echo5Server:

imports = append(imports, AdditionalImport{Package: "github.com/labstack/echo/v5"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictecho5", Package: "github.com/oapi-codegen/runtime/strictmiddleware/echo-v5"})

}

case g.ChiServer:

imports = append(imports, AdditionalImport{Package: "github.com/go-chi/chi/v5"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictnethttp", Package: "github.com/oapi-codegen/runtime/strictmiddleware/nethttp"})

}

case g.GinServer:

imports = append(imports, AdditionalImport{Package: "github.com/gin-gonic/gin"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictgin", Package: "github.com/oapi-codegen/runtime/strictmiddleware/gin"})

}

case g.GorillaServer:

imports = append(imports, AdditionalImport{Package: "github.com/gorilla/mux"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictnethttp", Package: "github.com/oapi-codegen/runtime/strictmiddleware/nethttp"})

}

case g.FiberServer:

imports = append(imports, AdditionalImport{Package: "github.com/gofiber/fiber/v2"})

case g.IrisServer:

imports = append(imports, AdditionalImport{Package: "github.com/kataras/iris/v12"})

imports = append(imports, AdditionalImport{Package: "github.com/kataras/iris/v12/core/router"})

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictiris", Package: "github.com/oapi-codegen/runtime/strictmiddleware/iris"})

}

case g.StdHTTPServer:

if g.Strict {

imports = append(imports, AdditionalImport{Alias: "strictnethttp", Package: "github.com/oapi-codegen/runtime/strictmiddleware/nethttp"})

}

}

return imports

}

func (oo GenerateOptions) Validate() map[string]string {

return nil

}

func (oo GenerateOptions) Warnings() map[string]string {

warnings := make(map[string]string)

if oo.StdHTTPServer {

if warning := oo.warningForStdHTTP(); warning != "" {

warnings["std-http-server"] = warning

}

}

return warnings

}

func (oo GenerateOptions) warningForStdHTTP() string {

pathToGoMod, mod, err := findAndParseGoModuleForDepth(".", maximumDepthToSearchForGoMod)

if err != nil {

return fmt.Sprintf("Encountered an error while trying to find a `go.mod` or a `tools.mod` in this directory, or %d levels above it: %v", maximumDepthToSearchForGoMod, err)

}

if mod == nil {

return fmt.Sprintf("Failed to find a `go.mod` or a `tools.mod` in this directory, or %d levels above it, so unable to validate that you're using Go 1.22+. If you start seeing API interactions resulting in a `404 page not found`, the Go directive (implying source compatibility for this module) needs to be bumped. See also: https://www.jvt.me/posts/2024/03/04/go-net-http-why-404/", maximumDepthToSearchForGoMod)

}

if !hasMinimalMinorGoDirective(minimumGoVersionForGenerateStdHTTPServer, mod) {

return fmt.Sprintf("Found a `go.mod` or a `tools.mod` at path %v, but it only had a version of %v, whereas the minimum required is 1.%d. It's very likely API interactions will result in a `404 page not found`. The Go directive (implying source compatibility for this module) needs to be bumped. See also: https://www.jvt.me/posts/2024/03/04/go-net-http-why-404/", pathToGoMod, mod.Go.Version, minimumGoVersionForGenerateStdHTTPServer)

}

return ""

}

// CompatibilityOptions specifies backward compatibility settings for the

// code generator.

type CompatibilityOptions struct {

// In the past, we merged schemas for `allOf` by inlining each schema

// within the schema list. This approach, though, is incorrect because

// `allOf` merges at the schema definition level, not at the resulting model

// level. So, new behavior merges OpenAPI specs but generates different code

// than we have in the past. Set OldMergeSchemas to true for the old behavior.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/531

OldMergeSchemas bool `yaml:"old-merge-schemas,omitempty"`

// Enum values can generate conflicting typenames, so we've updated the

// code for enum generation to avoid these conflicts, but it will result

// in some enum types being renamed in existing code. Set OldEnumConflicts to true

// to revert to old behavior. Please see:

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/549

OldEnumConflicts bool `yaml:"old-enum-conflicts,omitempty"`

// It was a mistake to generate a go type definition for every $ref in

// the OpenAPI schema. New behavior uses type aliases where possible, but

// this can generate code which breaks existing builds. Set OldAliasing to true

// for old behavior.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/549

OldAliasing bool `yaml:"old-aliasing,omitempty"`

// When an object contains no members, and only an additionalProperties specification,

// it is flattened to a map

DisableFlattenAdditionalProperties bool `yaml:"disable-flatten-additional-properties,omitempty"`

// When an object property is both required and readOnly the go model is generated

// as a pointer. Set DisableRequiredReadOnlyAsPointer to true to mark them as non pointer.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/604

DisableRequiredReadOnlyAsPointer bool `yaml:"disable-required-readonly-as-pointer,omitempty"`

// When set to true, always prefix enum values with their type name instead of only

// when typenames would be conflicting.

AlwaysPrefixEnumValues bool `yaml:"always-prefix-enum-values,omitempty"`

// Our generated code for Chi has historically inverted the order in which Chi middleware is

// applied such that the last invoked middleware ends up executing first in the Chi chain

// This resolves the behavior such that middlewares are chained in the order they are invoked.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/786

ApplyChiMiddlewareFirstToLast bool `yaml:"apply-chi-middleware-first-to-last,omitempty"`

// Our generated code for gorilla/mux has historically inverted the order in which gorilla/mux middleware is

// applied such that the last invoked middleware ends up executing first in the middlewares chain

// This resolves the behavior such that middlewares are chained in the order they are invoked.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/841

ApplyGorillaMiddlewareFirstToLast bool `yaml:"apply-gorilla-middleware-first-to-last,omitempty"`

// CircularReferenceLimit allows controlling the limit for circular reference checking.

// In some OpenAPI specifications, we have a higher number of circular

// references than is allowed out-of-the-box, but can be tuned to allow

// traversing them.

// Deprecated: In kin-openapi v0.126.0 (https://github.com/getkin/kin-openapi/tree/v0.126.0?tab=readme-ov-file#v01260) the Circular Reference Counter functionality was removed, instead resolving all references with backtracking, to avoid needing to provide a limit to reference counts.

CircularReferenceLimit int `yaml:"circular-reference-limit"`

// AllowUnexportedStructFieldNames makes it possible to output structs that have fields that are unexported.

//

// This is expected to be used in conjunction with `x-go-name` and `x-oapi-codegen-only-honour-go-name` to override the resulting output field name, and `x-oapi-codegen-extra-tags` to not produce JSON tags for `encoding/json`, such as:

//

// ```yaml

// id:

// type: string

// x-go-name: accountIdentifier

// x-oapi-codegen-extra-tags:

// json: "-"

// x-oapi-codegen-only-honour-go-name: true

// ```

//

// NOTE that this can be confusing to users of your OpenAPI specification, who may see a field present and therefore be expecting to see/use it in the request/response, without understanding the nuance of how `oapi-codegen` generates the code.

AllowUnexportedStructFieldNames bool `yaml:"allow-unexported-struct-field-names"`

// PreserveOriginalOperationIdCasingInEmbeddedSpec ensures that the `operationId` from the source spec is kept intact in case when embedding it into the Embedded Spec output.

// When `oapi-codegen` parses the original OpenAPI specification, it will apply the configured `output-options.name-normalizer` to each operation's `operationId` before that is used to generate code from.

// However, this is also applied to the copy of the `operationId`s in the `embedded-spec` generation, which means that the embedded OpenAPI specification is then out-of-sync with the input specificiation.

// To ensure that the `operationId` in the embedded spec is preserved as-is from the input specification, set this.

// NOTE that this will not impact generated code.

// NOTE that if you're using `include-operation-ids` or `exclude-operation-ids` you may want to ensure that the `operationId`s used are correct.

PreserveOriginalOperationIdCasingInEmbeddedSpec bool `yaml:"preserve-original-operation-id-casing-in-embedded-spec"`

// HeadersImplicitlyRequired treats all response headers as required, ignoring

// the `required` property from the header definition. Prior to v2.6.0,

// oapi-codegen generated all response headers as direct values (implicitly

// required). The OpenAPI specification defaults headers to optional

// (required: false), so the corrected behavior generates optional headers as

// pointers. Set this to true to restore the old behavior where all headers

// are treated as required.

// Please see https://github.com/oapi-codegen/oapi-codegen/issues/2267

HeadersImplicitlyRequired bool `yaml:"headers-implicitly-required,omitempty"`

}

func (co CompatibilityOptions) Validate() map[string]string {

return nil

}

// OutputOptions are used to modify the output code in some way.

type OutputOptions struct {

// Whether to skip go imports on the generated code

SkipFmt bool `yaml:"skip-fmt,omitempty"`

// Whether to skip pruning unused components on the generated code

SkipPrune bool `yaml:"skip-prune,omitempty"`

// Only include operations that have one of these tags. Ignored when empty.

IncludeTags []string `yaml:"include-tags,omitempty"`

// Exclude operations that have one of these tags. Ignored when empty.

ExcludeTags []string `yaml:"exclude-tags,omitempty"`

// Only include operations that have one of these operation-ids. Ignored when empty.

IncludeOperationIDs []string `yaml:"include-operation-ids,omitempty"`

// Exclude operations that have one of these operation-ids. Ignored when empty.

ExcludeOperationIDs []string `yaml:"exclude-operation-ids,omitempty"`

// Override built-in templates from user-provided files

UserTemplates map[string]string `yaml:"user-templates,omitempty"`

// Exclude from generation schemas with given names. Ignored when empty.

ExcludeSchemas []string `yaml:"exclude-schemas,omitempty"`

// The suffix used for responses types

ResponseTypeSuffix string `yaml:"response-type-suffix,omitempty"`

// Override the default generated client type with the value

ClientTypeName string `yaml:"client-type-name,omitempty"`

// AdditionalInitialisms is a list of additional initialisms to use when generating names.

// NOTE that this has no effect unless the `name-normalizer` is set to `ToCamelCaseWithInitialisms`

AdditionalInitialisms []string `yaml:"additional-initialisms,omitempty"`

// Whether to generate nullable type for nullable fields

NullableType bool `yaml:"nullable-type,omitempty"`

// DisableTypeAliasesForType allows defining which OpenAPI `type`s will explicitly not use type aliases

// Currently supports:

// "array"

DisableTypeAliasesForType []string `yaml:"disable-type-aliases-for-type"`

// NameNormalizer is the method used to normalize Go names and types, for instance converting the text `MyApi` to `MyAPI`. Corresponds with the constants defined for `codegen.NameNormalizerFunction`

NameNormalizer string `yaml:"name-normalizer,omitempty"`

// Overlay defines configuration for the OpenAPI Overlay (https://github.com/OAI/Overlay-Specification) to manipulate the OpenAPI specification before generation. This allows modifying the specification without needing to apply changes directly to it, making it easier to keep it up-to-date.

Overlay OutputOptionsOverlay `yaml:"overlay"`

// EnableYamlTags adds YAML tags to generated structs, in addition to default JSON ones

EnableYamlTags bool `yaml:"yaml-tags,omitempty"`

// ClientResponseBytesFunction decides whether to enable the generation of a `Bytes()` method on response objects for `ClientWithResponses`

ClientResponseBytesFunction bool `yaml:"client-response-bytes-function,omitempty"`

// PreferSkipOptionalPointer allows defining at a global level whether to omit the pointer for a type to indicate that the field/type is optional.

// This is the same as adding `x-go-type-skip-optional-pointer` to each field (manually, or using an OpenAPI Overlay)

PreferSkipOptionalPointer bool `yaml:"prefer-skip-optional-pointer,omitempty"`

// PreferSkipOptionalPointerWithOmitzero allows generating the `omitzero` JSON tag types that would have had an optional pointer.

// This is the same as adding `x-omitzero` to each field (manually, or using an OpenAPI Overlay).

// A field can set `x-omitzero: false` to disable the `omitzero` JSON tag.

// NOTE that this must be used alongside `prefer-skip-optional-pointer`, otherwise makes no difference.

PreferSkipOptionalPointerWithOmitzero bool `yaml:"prefer-skip-optional-pointer-with-omitzero,omitempty"`

// PreferSkipOptionalPointerOnContainerTypes allows disabling the generation of an "optional pointer" for an optional field that is a container type (such as a slice or a map), which ends up requiring an additional, unnecessary, `... != nil` check

PreferSkipOptionalPointerOnContainerTypes bool `yaml:"prefer-skip-optional-pointer-on-container-types,omitempty"`

// ResolveTypeNameCollisions, when set to true, automatically renames

// types that collide across different OpenAPI component sections

// (schemas, parameters, requestBodies, responses, headers) by appending

// a suffix based on the component section (e.g., "Parameter", "Response",

// "RequestBody"). It also detects collisions between component types and

// client response wrapper types (e.g., issue #1474). Without this, the

// codegen will error on duplicate type names, requiring manual resolution

// via x-go-name.

ResolveTypeNameCollisions bool `yaml:"resolve-type-name-collisions,omitempty"`

// TypeMapping allows customizing OpenAPI type/format to Go type mappings.

// User-specified mappings are merged on top of the defaults.

TypeMapping *TypeMapping `yaml:"type-mapping,omitempty"`

}

func (oo OutputOptions) Validate() map[string]string {

if NameNormalizerFunction(oo.NameNormalizer) != NameNormalizerFunctionToCamelCaseWithInitialisms && len(oo.AdditionalInitialisms) > 0 {

return map[string]string{

"additional-initialisms": "You have specified `additional-initialisms`, but the `name-normalizer` is not set to `ToCamelCaseWithInitialisms`. Please specify `name-normalizer: ToCamelCaseWithInitialisms` or remove the `additional-initialisms` configuration",

}

}

return nil

}

type OutputOptionsOverlay struct {

Path string `yaml:"path"`

// Strict defines whether the Overlay should be applied in a strict way, highlighting any actions that will not take any effect. This can, however, lead to more work when testing new actions in an Overlay, so can be turned off with this setting.

// Defaults to true.

Strict *bool `yaml:"strict,omitempty"`

}