Refitter is a CLI tool for generating a C# REST API Client using the Refit library. Refitter can generate the Refit interface from OpenAPI specifications
Installation:
The tool is packaged as a .NET Tool and is published to nuget.org. You can install the latest version of this tool like this:
dotnet tool install --global Refitter
Usage:
$ refitter --helpUSAGE:
refitter [URL or input file] [OPTIONS]
EXAMPLES:
refitter ./openapi.json
refitter https://petstore3.swagger.io/api/v3/openapi.yaml
refitter ./openapi.json --namespace "Your.Namespace.Of.Choice.GeneratedCode" --output ./GeneratedCode.cs
refitter ./openapi.json --namespace "Your.Namespace.Of.Choice.GeneratedCode" --internal
refitter ./openapi.json --output ./IGeneratedCode.cs --interface-only
refitter ./openapi.json --use-api-response
refitter ./openapi.json --cancellation-tokens
refitter ./openapi.json --no-operation-headers
refitter ./openapi.json --use-iso-date-format
refitter ./openapi.json --additional-namespace "Your.Additional.Namespace" --additional-namespace "Your.Other.Additional.Namespace"
refitter ./openapi.json --multiple-interfaces ByEndpoint
ARGUMENTS:
[URL or input file] URL or file path to OpenAPI Specification file
OPTIONS:
DEFAULT
-h, --help Prints help information
-n, --namespace GeneratedCode Default namespace to use for generated types
-o, --output Output.cs Path to Output file
--no-auto-generated-header Don't add <auto-generated> header to output file
--interface-only Don't generate contract types
--use-api-response Return Task<IApiResponse<T>> instead of Task<T>
--internal Set the accessibility of the generated types to 'internal'
--cancellation-tokens Use cancellation tokens
--no-operation-headers Don't generate operation headers
--no-logging Don't log errors or collect telemetry
--additional-namespace Add additional namespace to generated types
--use-iso-date-format Explicitly format date query string parameters in ISO 8601 standard date format using delimiters (2023-06-15)
--multiple-interfaces Generate a Refit interface for each endpoint. May be one of ByEndpoint, ByTag
To generate code from an OpenAPI specifications file, run the following:
$ refitter [path to OpenAPI spec file] --namespace "[Your.Namespace.Of.Choice.GeneratedCode]"
This will generate a file called Output.cs which contains the Refit interface and contract classes generated using NSwag
using Refit;
using System.Threading.Tasks;
using System.Collections.Generic;
namespace Your.Namespace.Of.Choice.GeneratedCode
{
public interface ISwaggerPetstore
{
/// <summary>
/// Update an existing pet by Id
/// </summary>
[Put("/pet")]
Task<Pet> UpdatePet([Body] Pet body);
/// <summary>
/// Add a new pet to the store
/// </summary>
[Post("/pet")]
Task<Pet> AddPet([Body] Pet body);
/// <summary>
/// Multiple status values can be provided with comma separated strings
/// </summary>
[Get("/pet/findByStatus")]
Task<ICollection<Pet>> FindPetsByStatus([Query] Status? status);
/// <summary>
/// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
/// </summary>
[Get("/pet/findByTags")]
Task<ICollection<Pet>> FindPetsByTags([Query(CollectionFormat.Multi)] IEnumerable<string> tags);
/// <summary>
/// Returns a single pet
/// </summary>
[Get("/pet/{petId}")]
Task<Pet> GetPetById(long petId);
[Post("/pet/{petId}")]
Task UpdatePetWithForm(long petId, [Query] string name, [Query] string status);
[Delete("/pet/{petId}")]
Task DeletePet(long petId, [Header("api_key")] string api_key);
[Post("/pet/{petId}/uploadImage")]
Task<ApiResponse> UploadFile(long petId, [Query] string additionalMetadata, StreamPart body);
/// <summary>
/// Returns a map of status codes to quantities
/// </summary>
[Get("/store/inventory")]
Task<IDictionary<string, int>> GetInventory();
/// <summary>
/// Place a new order in the store
/// </summary>
[Post("/store/order")]
Task<Order> PlaceOrder([Body] Order body);
/// <summary>
/// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
/// </summary>
[Get("/store/order/{orderId}")]
Task<Order> GetOrderById(long orderId);
/// <summary>
/// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
/// </summary>
[Delete("/store/order/{orderId}")]
Task DeleteOrder(long orderId);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Post("/user")]
Task CreateUser([Body] User body);
/// <summary>
/// Creates list of users with given input array
/// </summary>
[Post("/user/createWithList")]
Task<User> CreateUsersWithListInput([Body] IEnumerable<User> body);
[Get("/user/login")]
Task<string> LoginUser([Query] string username, [Query] string password);
[Get("/user/logout")]
Task LogoutUser();
[Get("/user/{username}")]
Task<User> GetUserByName(string username);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Put("/user/{username}")]
Task UpdateUser(string username, [Body] User body);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Delete("/user/{username}")]
Task DeleteUser(string username);
}
}
Here's an example generated output from the Swagger Petstore example configured to wrap the return type in IApiResponse<T>
using Refit;
using System.Threading.Tasks;
using System.Collections.Generic;
namespace Your.Namespace.Of.Choice.GeneratedCode.WithApiResponse
{
public interface ISwaggerPetstore
{
/// <summary>
/// Update an existing pet by Id
/// </summary>
[Put("/pet")]
Task<IApiResponse<Pet>> UpdatePet([Body] Pet body);
/// <summary>
/// Add a new pet to the store
/// </summary>
[Post("/pet")]
Task<IApiResponse<Pet>> AddPet([Body] Pet body);
/// <summary>
/// Multiple status values can be provided with comma separated strings
/// </summary>
[Get("/pet/findByStatus")]
Task<IApiResponse<ICollection<Pet>>> FindPetsByStatus([Query] Status? status);
/// <summary>
/// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
/// </summary>
[Get("/pet/findByTags")]
Task<IApiResponse<ICollection<Pet>>> FindPetsByTags([Query(CollectionFormat.Multi)] IEnumerable<string> tags);
/// <summary>
/// Returns a single pet
/// </summary>
[Get("/pet/{petId}")]
Task<IApiResponse<Pet>> GetPetById(long petId);
[Post("/pet/{petId}")]
Task UpdatePetWithForm(long petId, [Query] string name, [Query] string status);
[Delete("/pet/{petId}")]
Task DeletePet(long petId, [Header("api_key")] string api_key);
[Post("/pet/{petId}/uploadImage")]
Task<IApiResponse<ApiResponse>> UploadFile(long petId, [Query] string additionalMetadata, StreamPart body);
/// <summary>
/// Returns a map of status codes to quantities
/// </summary>
[Get("/store/inventory")]
Task<IApiResponse<IDictionary<string, int>>> GetInventory();
/// <summary>
/// Place a new order in the store
/// </summary>
[Post("/store/order")]
Task<IApiResponse<Order>> PlaceOrder([Body] Order body);
/// <summary>
/// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
/// </summary>
[Get("/store/order/{orderId}")]
Task<IApiResponse<Order>> GetOrderById(long orderId);
/// <summary>
/// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
/// </summary>
[Delete("/store/order/{orderId}")]
Task DeleteOrder(long orderId);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Post("/user")]
Task CreateUser([Body] User body);
/// <summary>
/// Creates list of users with given input array
/// </summary>
[Post("/user/createWithList")]
Task<IApiResponse<User>> CreateUsersWithListInput([Body] IEnumerable<User> body);
[Get("/user/login")]
Task<IApiResponse<string>> LoginUser([Query] string username, [Query] string password);
[Get("/user/logout")]
Task LogoutUser();
[Get("/user/{username}")]
Task<IApiResponse<User>> GetUserByName(string username);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Put("/user/{username}")]
Task UpdateUser(string username, [Body] User body);
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Delete("/user/{username}")]
Task DeleteUser(string username);
}
}
Here's an example generated output from the Swagger Petstore example configured to generate an interface for each endpoint
/// <summary>
/// Update an existing pet
/// </summary>
public interface IUpdatePetEndpoint
{
/// <summary>
/// Update an existing pet by Id
/// </summary>
[Put("/pet")]
Task<Pet> Execute([Body] Pet body);
}
/// <summary>
/// Add a new pet to the store
/// </summary>
public interface IAddPetEndpoint
{
/// <summary>
/// Add a new pet to the store
/// </summary>
[Post("/pet")]
Task<Pet> Execute([Body] Pet body);
}
/// <summary>
/// Finds Pets by status
/// </summary>
public interface IFindPetsByStatusEndpoint
{
/// <summary>
/// Multiple status values can be provided with comma separated strings
/// </summary>
[Get("/pet/findByStatus")]
Task<ICollection<Pet>> Execute([Query] Status? status);
}
/// <summary>
/// Finds Pets by tags
/// </summary>
public interface IFindPetsByTagsEndpoint
{
/// <summary>
/// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
/// </summary>
[Get("/pet/findByTags")]
Task<ICollection<Pet>> Execute([Query(CollectionFormat.Multi)] IEnumerable<string> tags);
}
/// <summary>
/// Find pet by ID
/// </summary>
public interface IGetPetByIdEndpoint
{
/// <summary>
/// Returns a single pet
/// </summary>
[Get("/pet/{petId}")]
Task<Pet> Execute(long petId);
}
/// <summary>
/// Updates a pet in the store with form data
/// </summary>
public interface IUpdatePetWithFormEndpoint
{
[Post("/pet/{petId}")]
Task Execute(long petId, [Query] string name, [Query] string status);
}
/// <summary>
/// Deletes a pet
/// </summary>
public interface IDeletePetEndpoint
{
[Delete("/pet/{petId}")]
Task Execute(long petId, [Header("api_key")] string api_key);
}
/// <summary>
/// uploads an image
/// </summary>
public interface IUploadFileEndpoint
{
[Post("/pet/{petId}/uploadImage")]
Task<ApiResponse> Execute(long petId, [Query] string additionalMetadata, StreamPart body);
}
/// <summary>
/// Returns pet inventories by status
/// </summary>
public interface IGetInventoryEndpoint
{
/// <summary>
/// Returns a map of status codes to quantities
/// </summary>
[Get("/store/inventory")]
Task<IDictionary<string, int>> Execute();
}
/// <summary>
/// Place an order for a pet
/// </summary>
public interface IPlaceOrderEndpoint
{
/// <summary>
/// Place a new order in the store
/// </summary>
[Post("/store/order")]
Task<Order> Execute([Body] Order body);
}
/// <summary>
/// Find purchase order by ID
/// </summary>
public interface IGetOrderByIdEndpoint
{
/// <summary>
/// For valid response try integer IDs with value <= 5 or > 10. Other values will generated exceptions
/// </summary>
[Get("/store/order/{orderId}")]
Task<Order> Execute(long orderId);
}
/// <summary>
/// Delete purchase order by ID
/// </summary>
public interface IDeleteOrderEndpoint
{
/// <summary>
/// For valid response try integer IDs with value < 1000. Anything above 1000 or nonintegers will generate API errors
/// </summary>
[Delete("/store/order/{orderId}")]
Task Execute(long orderId);
}
/// <summary>
/// Create user
/// </summary>
public interface ICreateUserEndpoint
{
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Post("/user")]
Task Execute([Body] User body);
}
/// <summary>
/// Creates list of users with given input array
/// </summary>
public interface ICreateUsersWithListInputEndpoint
{
/// <summary>
/// Creates list of users with given input array
/// </summary>
[Post("/user/createWithList")]
Task<User> Execute([Body] IEnumerable<User> body);
}
/// <summary>
/// Logs user into the system
/// </summary>
public interface ILoginUserEndpoint
{
[Get("/user/login")]
Task<string> Execute([Query] string username, [Query] string password);
}
/// <summary>
/// Logs out current logged in user session
/// </summary>
public interface ILogoutUserEndpoint
{
[Get("/user/logout")]
Task Execute();
}
/// <summary>
/// Get user by user name
/// </summary>
public interface IGetUserByNameEndpoint
{
[Get("/user/{username}")]
Task<User> Execute(string username);
}
/// <summary>
/// Update user
/// </summary>
public interface IUpdateUserEndpoint
{
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Put("/user/{username}")]
Task Execute(string username, [Body] User body);
}
/// <summary>
/// Delete user
/// </summary>
public interface IDeleteUserEndpoint
{
/// <summary>
/// This can only be done by the logged in user.
/// </summary>
[Delete("/user/{username}")]
Task Execute(string username);
}
RestService
Here's an example usage of the generated code above
using Refit;
using System;
using System.Threading.Tasks;
namespace Your.Namespace.Of.Choice.GeneratedCode;
internal class Program
{
private static async Task Main(string[] args)
{
var client = RestService.For<ISwaggerPetstore>("https://petstore3.swagger.io/api/v3");
var pet = await client.GetPetById(1);
Console.WriteLine("## Using Task<T> as return type ##");
Console.WriteLine($"Name: {pet.Name}");
Console.WriteLine($"Category: {pet.Category.Name}");
Console.WriteLine($"Status: {pet.Status}");
Console.WriteLine();
var client2 = RestService.For<WithApiResponse.ISwaggerPetstore>("https://petstore3.swagger.io/api/v3");
var response = await client2.GetPetById(2);
Console.WriteLine("## Using Task<IApiResponse<T>> as return type ##");
Console.WriteLine($"HTTP Status Code: {response.StatusCode}");
Console.WriteLine($"Name: {response.Content.Name}");
Console.WriteLine($"Category: {response.Content.Category.Name}");
Console.WriteLine($"Status: {response.Content.Status}");
}
}
The RestService class generates an implementation of ISwaggerPetstore that uses HttpClient to make its calls.
The code above when run will output something like this:
## Using Task<T> as return type ##
Name: Gatitotototo
Category: Chaucito
Status: Sold
## Using Task<IApiResponse<T>> as return type ##
HTTP Status Code: OK
Name: Gatitotototo
Category: Chaucito
Status: Sold