using System;

using ServiceStack.Web;

using ServiceStack.Host.Handlers;

using ServiceStack.Text;

namespace ServiceStack;

/// <summary>

/// Add a new API Handler at a custom route.

///

/// RawHttpHandlers.Add(ApiHandlers.Json("/api/{Request}")) => delegates /api/* requests to JSON Request Handler, e.g:

/// - /api/Hello => {"result":"Hello"}

/// - /api/Hello?name=World => {"result":"Hello, World"}

/// </summary>

public static class ApiHandlers

{

public static Func<IHttpRequest, HttpAsyncTaskHandler> Json(string apiPath) =>

Generic(apiPath, MimeTypes.Json, RequestAttributes.Reply | RequestAttributes.Json, Feature.Json);

public static Func<IHttpRequest, HttpAsyncTaskHandler> Jsv(string apiPath) =>

Generic(apiPath, MimeTypes.Jsv, RequestAttributes.Reply | RequestAttributes.Jsv, Feature.Jsv);

public static Func<IHttpRequest, HttpAsyncTaskHandler> Csv(string apiPath) =>

Generic(apiPath, MimeTypes.Csv, RequestAttributes.Reply | RequestAttributes.Csv, Feature.Csv);

public static Func<IHttpRequest, HttpAsyncTaskHandler> Xml(string apiPath) =>

Generic(apiPath, MimeTypes.Xml, RequestAttributes.Reply | RequestAttributes.Xml, Feature.Xml);

public static Func<IHttpRequest, HttpAsyncTaskHandler> Generic(string apiPath,

string contentType, RequestAttributes requestAttributes, Feature features)

{

var baseApiPath = GetBaseApiPath(apiPath);

var useApiPath = apiPath.LastLeftPart('/') + '/';

return req => {

// Don't handle OPTIONS CORS requests

if (req.HttpMethod == HttpMethods.Options)

{

var emitHandler = HostContext.GetPlugin<CorsFeature>()?.EmitGlobalHeadersHandler;

if (emitHandler != null)

return emitHandler;

return null;

}

var pathInfo = req.PathInfo;

if (pathInfo == baseApiPath || pathInfo.StartsWith(useApiPath))

{

// Add support for overriding content type with ext, e.g. .csv

var apiName = pathInfo == baseApiPath ? "" : pathInfo.LastRightPart('/');

if (string.IsNullOrEmpty(apiName))

{

var feature = HostContext.GetPlugin<PredefinedRoutesFeature>();

if (feature?.ApiIndex != null)

{

var ret = feature.ApiIndex(req);

return new CustomActionHandlerAsync(async (req, res) =>

{

res.ContentType = contentType;

var serializer = HostContext.ContentTypes.GetStreamSerializerAsync(contentType);

await serializer(req, ret, req.Response.OutputStream).ConfigAwait();

});

}

return new NotFoundHttpHandler();

}

var useContentType = contentType;

var useRequestAttrs = requestAttributes;

var useFeature = features;

if (apiName.IndexOf('.') >= 0)

{

var ext = apiName.RightPart('.');

apiName = apiName.LeftPart('.');

useContentType = HostContext.ContentTypes.GetFormatContentType(ext);

useRequestAttrs = RequestAttributes.Reply | ContentFormat.GetEndpointAttributes(useContentType);

useFeature = useContentType.ToFeature();

}

return new GenericHandler(useContentType, useRequestAttrs, useFeature) {

RequestName = apiName

};

}

return null;

};

}

public static string GetBaseApiPath(string apiPath)

{

if (string.IsNullOrEmpty(apiPath))

throw new ArgumentNullException(nameof(apiPath));

if (apiPath[0] != '/')

throw new ArgumentException("must start with '/'", nameof(apiPath));

if (!apiPath.EndsWith("/{Request}"))

throw new ArgumentException("must end with '/{Request}'", nameof(apiPath));

var baseApiPath = apiPath.LastLeftPart('/');

return baseApiPath;

}

public static HttpAsyncTaskHandler JsonEndpointHandler(string apiPath, string pathInfo)

{

var useContentType = MimeTypes.Json;

var useRequestAttrs = RequestAttributes.Reply | RequestAttributes.Json;

var useFeature = Feature.Json;

var apiName = pathInfo == apiPath ? "" : pathInfo.LastRightPart('/');

if (string.IsNullOrEmpty(apiName))

return new NotFoundHttpHandler();

if (apiName.IndexOf('.') >= 0)

{

var ext = apiName.RightPart('.');

apiName = apiName.LeftPart('.');

useContentType = HostContext.ContentTypes.GetFormatContentType(ext);

useRequestAttrs = RequestAttributes.Reply | ContentFormat.GetEndpointAttributes(useContentType);

useFeature = useContentType.ToFeature();

}

return new GenericHandler(useContentType, useRequestAttrs, useFeature) {

RequestName = apiName

};

}

}