@loopback/docs

--- lang: en title: 'API docs: rest' keywords: LoopBack 4.0, LoopBack 4, Node.js, TypeScript, OpenAPI sidebar: lb4_sidebar editurl: https://github.com/loopbackio/loopback-next/tree/master/packages/rest permalink: /doc/en/lb4/apidocs.rest.html ---  [Home](./index.md) > [@loopback/rest](./rest.md) ## rest package The REST API package for loopback-next. ## Remarks A REST server for LoopBack 4 application instances, complete with: - new custom routing engine (special thanks to @bajtos)! - tools for defining your application routes - OpenAPI 3.0 spec (openapi.json/openapi.yaml) generation using @loopback/openapi-v3 - a default sequence implementation to manage the request and response lifecycle ## Classes | Class | Description | | --- | --- | | [BaseRoute](./rest.baseroute.md) | Base implementation of RouteEntry | | [ControllerRoute](./rest.controllerroute.md) | A route backed by a controller | | [DefaultSequence](./rest.defaultsequence.md) | The default implementation of SequenceHandler. | | [FindRouteMiddlewareProvider](./rest.findroutemiddlewareprovider.md) | | | [FindRouteProvider](./rest.findrouteprovider.md) | | | [HttpHandler](./rest.httphandler.md) | | | [InfoSpecEnhancer](./rest.infospecenhancer.md) | An OpenAPI spec enhancer to populate <code>info</code> with application metadata (package.json). | | [InvokeMethodMiddlewareProvider](./rest.invokemethodmiddlewareprovider.md) | | | [InvokeMethodProvider](./rest.invokemethodprovider.md) | | | [JsonBodyParser](./rest.jsonbodyparser.md) | | | [LogErrorProvider](./rest.logerrorprovider.md) | | | [MiddlewareSequence](./rest.middlewaresequence.md) | A sequence implementation using middleware chains | | [ParseParamsMiddlewareProvider](./rest.parseparamsmiddlewareprovider.md) | | | [ParseParamsProvider](./rest.parseparamsprovider.md) | Provides the function for parsing args in requests at runtime. | | [RawBodyParser](./rest.rawbodyparser.md) | Parsing the request body into Buffer | | [RedirectRoute](./rest.redirectroute.md) | | | [RegExpRouter](./rest.regexprouter.md) | Router implementation based on regexp matching | | [RejectProvider](./rest.rejectprovider.md) | | | [RequestBodyParser](./rest.requestbodyparser.md) | | | [RequestContext](./rest.requestcontext.md) | A per-request Context combining an IoC container with handler context (request, response, etc.). | | [RestApplication](./rest.restapplication.md) | An implementation of the Application class that automatically provides an instance of a REST server. This application class is intended to be a single-server implementation. Any attempt to bind additional servers will throw an error. | | [RestComponent](./rest.restcomponent.md) | | | [RestServer](./rest.restserver.md) | A REST API server for use with Loopback. Add this server to your application by importing the RestComponent. | | [Route](./rest.route.md) | | | [RouteSource](./rest.routesource.md) | | | [RoutingTable](./rest.routingtable.md) | Routing table | | [SendProvider](./rest.sendprovider.md) | Provides the function that populates the response object with the results of the operation. | | [SendResponseMiddlewareProvider](./rest.sendresponsemiddlewareprovider.md) | | | [StreamBodyParser](./rest.streambodyparser.md) | A special body parser to retain request stream as is. It will be used by explicitly setting <code>x-parser</code> to <code>'stream'</code> in the request body spec. | | [TextBodyParser](./rest.textbodyparser.md) | | | [Trie](./rest.trie.md) | An implementation of trie for routes. The key hierarchy is built with parts of the route path delimited by <code>/</code> | | [TrieRouter](./rest.trierouter.md) | Router implementation based on trie | | [UrlEncodedBodyParser](./rest.urlencodedbodyparser.md) | | ## Functions | Function | Description | | --- | --- | | [assignRouterSpec(target, additions)](./rest.assignrouterspec.md) | | | [compareRoute(route1, route2)](./rest.compareroute.md) | Compare two routes by verb/path for sorting | | [createBodyParserBinding(parserClass, key)](./rest.createbodyparserbinding.md) | Create a binding for the given body parser class | | [createControllerFactoryForBinding(key)](./rest.createcontrollerfactoryforbinding.md) | Create a controller factory function for a given binding key | | [createControllerFactoryForClass(controllerCtor)](./rest.createcontrollerfactoryforclass.md) | Create a controller factory function for a given class | | [createControllerFactoryForInstance(controllerInst)](./rest.createcontrollerfactoryforinstance.md) | Create a controller factory function for a given instance | | [createResolvedRoute(route, pathParams)](./rest.createresolvedroute.md) | | | [createRoutesForController(spec, controllerCtor, controllerFactory)](./rest.createroutesforcontroller.md) | Create routes for a controller with the given spec | | [getContentType(req)](./rest.getcontenttype.md) | Get the content-type header value from the request | | [getParserOptions(type, options)](./rest.getparseroptions.md) | Extract parser options based on the parser type | | [getParserOptions(type, options)](./rest.getparseroptions_1.md) | | | [getParserOptions(type, options)](./rest.getparseroptions_2.md) | | | [getParserOptions(type, options)](./rest.getparseroptions_3.md) | | | [getPathVariables(path)](./rest.getpathvariables.md) | Get all path variables. For example, <code>/root/{foo}/bar</code> => <code>['foo']</code> | | [invokeBodyParserMiddleware(handle, request)](./rest.invokebodyparsermiddleware.md) | Parse the request body asynchronously | | [joinPath(basePath, path)](./rest.joinpath.md) | | | [normalizeParsingError(err)](./rest.normalizeparsingerror.md) | Normalize parsing errors as <code>4xx</code> | | [parseJson(text, reviver, prohibitedKeys)](./rest.parsejson.md) | Parse a json string that rejects prohibited keys | | [parseOperationArgs(request, route, requestBodyParser, options)](./rest.parseoperationargs.md) | Parses the request to derive arguments to be passed in for the Application controller method | | [rebaseOpenApiSpec(spec, basePath)](./rest.rebaseopenapispec.md) | | | [sanitizeJsonParse(reviver, prohibitedKeys)](./rest.sanitizejsonparse.md) | Factory to create a reviver function for <code>JSON.parse</code> to sanitize keys | | [toExpressPath(path)](./rest.toexpresspath.md) | Convert an OpenAPI path to Express (path-to-regexp) style | | [validateApiPath(path)](./rest.validateapipath.md) | Validate the path to be compatible with OpenAPI path template. No parameter modifier, custom pattern, or unnamed parameter is allowed. | | [validateRequestBody(body, requestBodySpec, globalSchemas, options)](./rest.validaterequestbody.md) | Check whether the request body is valid according to the provided OpenAPI schema. The JSON schema is generated from the OpenAPI schema which is typically defined by <code>@requestBody()</code>. The validation leverages AJV schema validator. | | [validateValueAgainstSchema(value, schema, globalSchemas, options)](./rest.validatevalueagainstschema.md) | Validate the value against JSON schema. | | [writeResultToResponse(response, result)](./rest.writeresulttoresponse.md) | Writes the result from Application controller method into the HTTP response | ## Interfaces | Interface | Description | | --- | --- | | [ApiExplorerOptions](./rest.apiexploreroptions.md) | | | [BodyParser](./rest.bodyparser.md) | Interface to be implemented by body parser extensions | | [HttpServerLike](./rest.httpserverlike.md) | | | [Node](./rest.node.md) | A Node in the trie | | [OpenApiSpecForm](./rest.openapispecform.md) | The form of OpenAPI specs to be served | | [OpenApiSpecOptions](./rest.openapispecoptions.md) | Options to customize how OpenAPI specs are served | | [RequestBodyParserOptions](./rest.requestbodyparseroptions.md) | Options for request body parsing See https://github.com/expressjs/body-parser/\#optionsBuilt-in parsers retrieve their own options from the request body parser options. The parser specific properties override common ones. | | [RequestWithSession](./rest.requestwithsession.md) | extending express request type with a session field | | [ResolvedNode](./rest.resolvednode.md) | | | [ResolvedRoute](./rest.resolvedroute.md) | A route with path parameters resolved | | [RestRouter](./rest.restrouter.md) | | | [RestServerResolvedOptions](./rest.restserverresolvedoptions.md) | | | [RouteEntry](./rest.routeentry.md) | An entry in the routing table | | [SequenceHandler](./rest.sequencehandler.md) | A sequence handler is a class implementing sequence of actions required to handle an incoming request. | | [Session](./rest.session.md) | interface to set variables in user session | | [SessionUserProfile](./rest.sessionuserprofile.md) | user profile to add in session | | [ValidationOptions](./rest.validationoptions.md) | Options for request body validation using AJV | | [ValueValidationOptions](./rest.valuevalidationoptions.md) | Options for any value validation using AJV | ## Namespaces | Namespace | Description | | --- | --- | | [builtinParsers](./rest.builtinparsers.md) | | | [RestBindings](./rest.restbindings.md) | RestServer-specific bindings | | [RestHttpErrors](./rest.resthttperrors.md) | | | [RestMiddlewareGroups](./rest.restmiddlewaregroups.md) | Built-in middleware groups for the REST sequence | | [RestTags](./rest.resttags.md) | Binding tags for RestServer | ## Variables | Variable | Description | | --- | --- | | [DEFAULT\_LIMIT](./rest.default_limit.md) | | | [ERR\_NO\_MULTI\_SERVER](./rest.err_no_multi_server.md) | | | [REQUEST\_BODY\_PARSER\_TAG](./rest.request_body_parser_tag.md) | Binding tag for request body parser extensions | | [SequenceActions](./rest.sequenceactions.md) | | ## Type Aliases | Type Alias | Description | | --- | --- | | [AjvErrorOptions](./rest.ajverroroptions.md) | Options for AJV errors | | [AjvFactory](./rest.ajvfactory.md) | Factory function for Ajv instances | | [AjvFormat](./rest.ajvformat.md) | Ajv format definition with a name | | [AjvKeyword](./rest.ajvkeyword.md) | Ajv keyword definition with a name | | [BodyParserFunction](./rest.bodyparserfunction.md) | Plain function for body parsing | | [BodyParserMiddleware](./rest.bodyparsermiddleware.md) | Express body parser function type | | [ControllerClass](./rest.controllerclass.md) | Controller class | | [ControllerFactory](./rest.controllerfactory.md) | A factory function to create controller instances synchronously or asynchronously | | [ControllerInstance](./rest.controllerinstance.md) | | | [FindRoute](./rest.findroute.md) | Find a route matching the incoming request. Throw an error when no route was found. | | [HttpRequestListener](./rest.httprequestlistener.md) | | | [InvokeMethod](./rest.invokemethod.md) | Invokes a method defined in the Application Controller | | [LogError](./rest.logerror.md) | Log information about a failed request. | | [NodeWithValue](./rest.nodewithvalue.md) | | | [OperationArgs](./rest.operationargs.md) | | | [OperationRetval](./rest.operationretval.md) | Return value of a controller method (a function implementing an operation). This is a type alias for "any", used to distinguish operation results from other "any" typed values. | | [ParseParams](./rest.parseparams.md) | A function to parse OpenAPI operation parameters for a given route | | [PathParameterValues](./rest.pathparametervalues.md) | | | [Reject](./rest.reject.md) | Reject the request with an error. | | [RequestBody](./rest.requestbody.md) | Request body with metadata | | [RequestBodyValidationOptions](./rest.requestbodyvalidationoptions.md) | | | [RestComponentConfig](./rest.restcomponentconfig.md) | | | [RestRouterOptions](./rest.restrouteroptions.md) | | | [RestServerConfig](./rest.restserverconfig.md) | Valid configuration for the RestServer constructor. | | [RestServerOptions](./rest.restserveroptions.md) | RestServer options | | [RestServerResolvedConfig](./rest.restserverresolvedconfig.md) | | | [RouterSpec](./rest.routerspec.md) | | | [SchemaValidatorCache](./rest.schemavalidatorcache.md) | Cache for AJV schema validators | | [Send](./rest.send.md) | Send the operation response back to the client. | | [SequenceFunction](./rest.sequencefunction.md) | A sequence function is a function implementing a custom sequence of actions to handle an incoming request. |