Oapi-codegen
External
Internal
Overview
Rewrite this after using it for two different services.
Installation
Get the latest version from https://github.com/deepmap/oapi-codegen/tags
Then:
go install github.com/deepmap/oapi-codegen/v2/cmd/oapi-codegen@v2.1.0
The installation will place the package under $GOPATH/pkg/mod/cache/download/github.com/deepmap
and $GOPATH/pkg/mod/github.com/deepmap
, will compile the binary and place it under ~/go/bin
.
Generate Code
Generate client and server code:
oapi-codegen -package petstore ./petstore-expanded.yaml > ./internal/petstore/petstore.gen.go
go mod tidy
The types, spec and server code can live in different packages. For suggestions on layout, see:
Makefile Support
.PHONY: generate_oapi_artifacts
generate_oapi_artifacts: internal/petstore/spec.gen.go internal/petstore/types.gen.go internal/petstore/server.gen.go internal/petstore/client.gen.go
internal/petstore/spec.gen.go: ./petstore.yaml
oapi-codegen -generate spec -package petstore $< > $@
internal/petstore/types.gen.go: ./petstore.yaml
oapi-codegen -generate types -package petstore $< > $@
internal/petstore/server.gen.go: ./petstore.yaml
oapi-codegen -generate server -package petstore $< > $@
internal/petstore/client.gen.go: ./petstore.yaml
oapi-codegen -generate client -package petstore $< > $@
Type Generation
Generate the types declared in the /components/schemas
section of the OpenAPI specification.
oapi-codegen -generate types -package petstore ./petstore-expanded.yaml > ./api/openapi-types.gen.go
Also see:
Server Code Generation
TODO:
- Understand and document "strict server"
By default, oapi-codegen
generates server code for the echo HTTP server.
oapi-codegen -generate server -package petstore ./petstore.yaml > ./internal/petstore/server.gen.go
For an example of how to set up an echo
server with the generated code, see:
For OpenAPI specification examples and their corresponding generated server code see:
Client Code Generation
The client code must be generated in the same package as the generated types, because it refers to them. See Type Generation above.
oapi-codegen -generate types -package api ./petstore-expanded.yaml > ./api/openapi-types.gen.go
oapi-codegen -generate client -package api ./petstore-expanded.yaml > ./api/openapi-client.gen.go
The generator creates ClientInterface
and ClientWithResponsesInterface
interfaces. TODO: Understand and document the difference?
Options
-package
The package name for the generated code.
-generate
Comma-separated list of code to generate; valid options: "types", "client", "chi-server", "server", "gin", "gorilla", "spec", "skip-fmt", "skip-prune", "fiber", "iris". The default is "types,client,server,spec".
types
See Type Generation above.
server
See Server Code Generation above.
chi-server
Generates server code for the chi HTTP server. The code is compatible with net/http
server:
oapi-codegen -generate chi-server -package petstore ./petstore.yaml > ./internal/petstore/server.gen.go
For an example of how to set up a net/http
server with the generated code, see:
client
See Client Code Generation above.
spec
TODO: what is this and how it is useful?
Generates this:
var swaggerSpec = []string{...}
func decodeSpec() ([]byte, error) {...}
var rawSpec = decodeSpecCached()
func decodeSpecCached() func() ([]byte, error) {...}
func PathToRawSpec(pathToFile string) map[string]func() ([]byte, error) {...}
func GetSwagger() (swagger *openapi3.T, err error) {...}