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diff --git a/docs/pages/1 - Cask: a Scala HTTP micro-framework .md b/docs/pages/1 - Cask: a Scala HTTP micro-framework .md new file mode 100644 index 0000000..22d879e --- /dev/null +++ b/docs/pages/1 - Cask: a Scala HTTP micro-framework .md @@ -0,0 +1,927 @@ +```scala +object MinimalApplication extends cask.MainRoutes{ + @cask.get("/") + def hello() = { + "Hello World!" + } + + @cask.post("/do-thing") + def doThing(request: cask.Request) = { + new String(request.data.readAllBytes()).reverse + } + + initialize() +} +``` + +[Cask](https://github.com/lihaoyi/cask) is a simple Scala web framework inspired +by Python's [Flask](http://flask.pocoo.org/docs/1.0/) project. It aims to bring +simplicity, flexibility and ease-of-use to Scala webservers, avoiding cryptic +DSLs or complicated asynchrony. + +Getting Started +--------------- + +The easiest way to begin using Cask is by downloading the +[Mill](http://www.lihaoyi.com/mill/) example project: + +- Install [Mill](http://www.lihaoyi.com/mill/) +- Unzip the $$$minimalApplication into a folder. This should + give you the following files: +```text +build.sc +app/src/MinimalExample.scala +app/test/src/ExampleTests.scala +``` + +- `cd` into the folder, and run + +```bash +mill -w app.runBackground +``` + +This will server up the Cask application on `http://localhost:8080`. You can +immediately start interacting with it either via the browser, or +programmatically via `curl` or a HTTP client like +[Requests-Scala](https://github.com/lihaoyi/requests-scala): + +```scala +val host = "http://localhost:8080" + +val success = requests.get(host) + +success.text() ==> "Hello World!" +success.statusCode ==> 200 + +requests.get(host + "/doesnt-exist").statusCode ==> 404 + +requests.post(host + "/do-thing", data = "hello").text() ==> "olleh" + +requests.get(host + "/do-thing").statusCode ==> 404 +``` + +These HTTP calls are part of the test suite for the example project, which you +can run using: + +```bash +mill -w app.test +``` + +Cask is just a Scala library, and you can use Cask in any existing Scala project +via the following coordinates: + +```scala +// Mill +ivy"com.lihaoyi::cask:0.1.0" + +// SBT +"com.lihaoyi" %% "cask" % "0.1.0" +``` + +Example Projects +---------------- + +### Minimal Example + +```scala +object MinimalApplication extends cask.MainRoutes{ + @cask.get("/") + def hello() = { + "Hello World!" + } + + @cask.post("/do-thing") + def doThing(request: cask.Request) = { + new String(request.data.readAllBytes()).reverse + } + + initialize() +} +``` + +- $$$minimalApplication + +The rough outline of how the minimal example works should be easy to understand: + +- You define an object that inherits from `cask.MainRoutes` + +- Define endpoints using annotated functions, using `@cask.get` or `@cask.post` + with the route they should match + +- Each function can return the data you want in the response, or a + `cask.Response` if you want further customization: response code, headers, + etc. + +- Your function can tale an optional `cask.Request`, which exposes the entire + incoming HTTP request if necessary. In the above example, we use it to read + the request body into a string and return it reversed. + +In most cases, Cask provides convenient helpers to extract exactly the data from +the incoming HTTP request that you need, while also de-serializing it into the +data type you need and returning meaningful errors if they are missing. Thus, +although you can always get all the data necessary through `cask.Request`, it is +often more convenient to use another way, which will go into below. + +As your application grows, you will likely want to split up the routes into +separate files, themselves separate from any configuration of the Main +entrypoint (e.g. overriding the port, host, default error handlers, etc.). You +can do this by splitting it up into `cask.Routes` and `cask.Main` objects: + +```scala +object MinimalRoutes extends cask.Routes{ + @cask.get("/") + def hello() = { + "Hello World!" + } + + @cask.post("/do-thing") + def doThing(request: cask.Request) = { + new String(request.data.readAllBytes()).reverse + } + + initialize() +} + +object MinimalMain extends cask.Main(MinimalRoutes) +``` + +- $$$minimalApplication2 +- +You can split up your routes into separate `cask.Routes` objects as makes sense +and pass them all into `cask.Main`. + +### Variable Routes + + +```scala +object VariableRoutes extends cask.MainRoutes{ + @cask.get("/user/:userName") + def showUserProfile(userName: String) = { + s"User $userName" + } + + @cask.get("/post/:postId") + def showPost(postId: Int, param: Seq[String]) = { + s"Post $postId $param" + } + + @cask.get("/path", subpath = true) + def showSubpath(subPath: cask.Subpath) = { + s"Subpath ${subPath.value}" + } + + initialize() +} +``` + +- $$$variableRoutes + +You can bind variables to endpoints by declaring them as parameters: these are +either taken from a path-segment matcher of the same name (e.g. `postId` above), +or from query-parameters of the same name (e.g. `param` above). You can make +`param` take a `: String` to match `?param=hello`, an `: Int` for `?param=123` a +`Seq[T]` (as above) for repeated params such as `?param=hello¶m=world`, or +`: Option[T]` for cases where the `?param=hello` is optional. + +If you need to capture the entire sub-path of the request, you can set the flag +`subpath=true` and ask for a `: cask.Subpath` (the name of the param doesn't +matter). This will make the route match any sub-path of the prefix given to the +`@cask` decorator, and give you the remainder to use in your endpoint logic. + +### Receiving Form-encoded or JSON data + + +```scala +object FormJsonPost extends cask.MainRoutes{ + @cask.postJson("/json") + def jsonEndpoint(value1: ujson.Js.Value, value2: Seq[Int]) = { + "OK " + value1 + " " + value2 + } + + @cask.postForm("/form") + def formEndpoint(value1: cask.FormValue, value2: Seq[Int]) = { + "OK " + value1 + " " + value2 + } + + @cask.postForm("/upload") + def uploadFile(image: cask.FormFile) = { + image.fileName + } + + initialize() +} +``` + +- $$$formJsonPost + +If you need to handle a JSON-encoded POST request, you can use the +`@cast.postJson` decorator. This assumes the posted request body is a JSON dict, +and uses its keys to populate the endpoint's parameters, either as raw +`ujson.Js.Value`s or deserialized into `Seq[Int]`s or other things. +Deserialization is handled using the +[uPickle](https://github.com/lihaoyi/upickle) JSON library, though you could +write your own version of `postJson` to work with any other JSON library of your +choice. + +Similarly, you can mark endpoints as `@cask.postForm`, in which case the +endpoints params will be taken from the form-encoded POST body either raw (as +`cask.FormValue`s) or deserialized into simple data structures. Use +`cask.FormFile` if you want the given form value to be a file upload. + +Both normal forms and multipart forms are handled the same way. + +If the necessary keys are not present in the JSON/form-encoded POST body, or the +deserialization into Scala data-types fails, a 400 response is returned +automatically with a helpful error message. + + +### Processing Cookies + + +```scala +object Cookies extends cask.MainRoutes{ + @cask.get("/read-cookie") + def readCookies(username: cask.Cookie) = { + username.value + } + + @cask.get("/store-cookie") + def storeCookies() = { + cask.Response( + "Cookies Set!", + cookies = Seq(cask.Cookie("username", "the username")) + ) + } + + @cask.get("/delete-cookie") + def deleteCookie() = { + cask.Response( + "Cookies Deleted!", + cookies = Seq(cask.Cookie("username", "", expires = java.time.Instant.EPOCH)) + ) + } + + initialize() +} +``` + +- $$$cookies + +Cookies are most easily read by declaring a `: cask.Cookie` parameter; the +parameter name is used to fetch the cookie you are interested in. Cookies can be +stored by setting the `cookie` attribute in the response, and deleted simply by +setting `expires = java.time.Instant.EPOCH` (i.e. to have expired a long time +ago) + +### Serving Static Files + +```scala +object StaticFiles extends cask.MainRoutes{ + @cask.get("/") + def index() = { + "Hello!" + } + + @cask.static("/static") + def staticRoutes() = "cask/resources/cask" + + initialize() +} +``` + +- $$$staticFiles + +You can ask Cask to serve static files by defining a `@cask.static` endpoint. +This will match any subpath of the value returned by the endpoint (e.g. above +`/static/file.txt`, `/static/folder/file.txt`, etc.) and return the file +contents from the corresponding file on disk (and 404 otherwise). + +### Redirects or Aborts + +```scala +object RedirectAbort extends cask.MainRoutes{ + @cask.get("/") + def index() = { + cask.Redirect("/login") + } + + @cask.get("/login") + def login() = { + cask.Abort(401) + } + + initialize() +} +``` + +- $$$redirectAbort + +Cask provides some convenient helpers `cask.Redirect` and `cask.Abort` which you +can return; these are simple wrappers around `cask.Request`, and simply set up +the relevant headers or status code for you. + +### Extending Endpoints with Decorators + + +```scala +object Decorated extends cask.MainRoutes{ + class User{ + override def toString = "[haoyi]" + } + class loggedIn extends cask.Decorator { + def wrapFunction(ctx: cask.ParamContext, delegate: Delegate): Returned = { + delegate(Map("user" -> new User())) + } + } + class withExtra extends cask.Decorator { + def wrapFunction(ctx: cask.ParamContext, delegate: Delegate): Returned = { + delegate(Map("extra" -> 31337)) + } + } + + @withExtra() + @cask.get("/hello/:world") + def hello(world: String)(extra: Int) = { + world + extra + } + + @loggedIn() + @cask.get("/internal/:world") + def internal(world: String)(user: User) = { + world + user + } + + @withExtra() + @loggedIn() + @cask.get("/internal-extra/:world") + def internalExtra(world: String)(user: User)(extra: Int) = { + world + user + extra + } + + @withExtra() + @loggedIn() + @cask.get("/ignore-extra/:world") + def ignoreExtra(world: String)(user: User) = { + world + user + } + + initialize() +} +``` + +- $$$decorateds + +You can write extra decorator annotations that stack on top of the existing +`@cask.get`/`@cask.post` to provide additional arguments or validation. This is +done by implementing the `cask.Decorator` interface and it's `getRawParams` +function. `getRawParams`: + +- Receives a `ParamContext`, which basically gives you full access to the + underlying undertow HTTP connection so you can pick out whatever data you + would like + +- Returns an `Either[Response, cask.Decor[Any]]`. Returning a `Left` lets you + bail out early with a fixed `cask.Response`, avoiding further processing. + Returning a `Right` provides a map of parameter names and values that will + then get passed to the endpoint function in consecutive parameter lists (shown + above), as well as an optional cleanup function that is run after the endpoint + terminates. + +Each additional decorator is responsible for one additional parameter list to +the right of the existing parameter lists, each of which can contain any number +of parameters. + +Decorators are useful for things like: + +- Making an endpoint return a HTTP 403 if the user isn't logged in, but if they are + logged in providing the `: User` object to the body of the endpoint function + +- Rate-limiting users by returning early with a HTTP 429 if a user tries to + access an endpoint too many times too quickly + +- Providing request-scoped values to the endpoint function: perhaps a database + transaction that commits when the function succeeds (and rolls-back if it + fails), or access to some system resource that needs to be released. + +For decorators that you wish to apply to multiple routes at once, you can define +them by overriding the `cask.Routes#decorators` field (to apply to every +endpoint in that routes object) or `cask.Main#mainDecorators` (to apply to every +endpoint, period): + +```scala +object Decorated2 extends cask.MainRoutes{ + class User{ + override def toString = "[haoyi]" + } + class loggedIn extends cask.Decorator { + def wrapFunction(ctx: cask.ParamContext, delegate: Delegate): Returned = { + delegate(Map("user" -> new User())) + } + } + class withExtra extends cask.Decorator { + def wrapFunction(ctx: cask.ParamContext, delegate: Delegate): Returned = { + delegate(Map("extra" -> 31337)) + } + } + + override def decorators = Seq(new withExtra()) + + @cask.get("/hello/:world") + def hello(world: String)(extra: Int) = { + world + extra + } + + @loggedIn() + @cask.get("/internal-extra/:world") + def internalExtra(world: String)(user: User)(extra: Int) = { + world + user + extra + } + + @loggedIn() + @cask.get("/ignore-extra/:world") + def ignoreExtra(world: String)(user: User) = { + world + user + } + + initialize() +} +``` + +- $$$decorated2 + +This is convenient for cases where you want a set of decorators to apply broadly +across your web application, and do not want to repeat them over and over at +every single endpoint. + +### Gzip & Deflated Responses + + +```scala +object Compress extends cask.MainRoutes{ + + @cask.decorators.compress + @cask.get("/") + def hello() = { + "Hello World! Hello World! Hello World!" + } + + initialize() +} + +``` + +- $$$compress + +Cask provides a useful `@cask.decorators.compress` decorator that gzips or +deflates a response body if possible. This is useful if you don't have a proxy +like Nginx or similar in front of your server to perform the compression for +you. + +Like all decorators, `@cask.decorators.compress` can be defined on a level of a +set of `cask.Routes`: + +```scala +object Compress2 extends cask.Routes{ + override def decorators = Seq(new cask.decorators.compress()) + + @cask.get("/") + def hello() = { + "Hello World! Hello World! Hello World!" + } + + initialize() +} + +object Compress2Main extends cask.Main(Compress2) +``` + +- $$$compress2 + +Or globally, in your `cask.Main`: + +```scala +object Compress3 extends cask.Routes{ + + @cask.get("/") + def hello() = { + "Hello World! Hello World! Hello World!" + } + + initialize() +} + +object Compress3Main extends cask.Main(Compress3){ + override def decorators = Seq(new cask.decorators.compress()) +} +``` + +- $$$compress3 + +### TodoMVC Api Server + + +```scala +object TodoMvcApi extends cask.MainRoutes{ + case class Todo(checked: Boolean, text: String) + object Todo{ + implicit def todoRW = upickle.default.macroRW[Todo] + } + var todos = Seq( + Todo(true, "Get started with Cask"), + Todo(false, "Profit!") + ) + + @cask.get("/list/:state") + def list(state: String) = { + val filteredTodos = state match{ + case "all" => todos + case "active" => todos.filter(!_.checked) + case "completed" => todos.filter(_.checked) + } + upickle.default.write(filteredTodos) + } + + @cask.post("/add") + def add(request: cask.Request) = { + todos = Seq(Todo(false, new String(request.data.readAllBytes()))) ++ todos + } + + @cask.post("/toggle/:index") + def toggle(index: Int) = { + todos = todos.updated(index, todos(index).copy(checked = !todos(index).checked)) + } + + @cask.post("/delete/:index") + def delete(index: Int) = { + todos = todos.patch(index, Nil, 1) + } + + initialize() +} +``` + +- $$$todoApi + +This is a simple self-contained example of using Cask to write an in-memory API +server for the common [TodoMVC example app](http://todomvc.com/). + +This minimal example intentionally does not contain javascript, HTML, styles, +etc.. Those can be managed via the normal mechanism for +[Serving Static Files](#serving-static-files). + + +### TodoMVC Database Integration + +```scala +import cask.internal.Router +import com.typesafe.config.ConfigFactory +import io.getquill.{SqliteJdbcContext, SnakeCase} + +object TodoMvcDb extends cask.MainRoutes{ + val tmpDb = java.nio.file.Files.createTempDirectory("todo-cask-sqlite") + + object ctx extends SqliteJdbcContext( + SnakeCase, + ConfigFactory.parseString( + s"""{"driverClassName":"org.sqlite.JDBC","jdbcUrl":"jdbc:sqlite:$tmpDb/file.db"}""" + ) + ) + + class transactional extends cask.Decorator{ + class TransactionFailed(val value: Router.Result.Error) extends Exception + def wrapFunction(pctx: cask.ParamContext, delegate: Delegate): Returned = { + try ctx.transaction( + delegate(Map()) match{ + case Router.Result.Success(t) => Router.Result.Success(t) + case e: Router.Result.Error => throw new TransactionFailed(e) + } + ) + catch{case e: TransactionFailed => e.value} + + } + } + + case class Todo(id: Int, checked: Boolean, text: String) + object Todo{ + implicit def todoRW = upickle.default.macroRW[Todo] + } + + ctx.executeAction( + """CREATE TABLE todo ( + | id INTEGER PRIMARY KEY AUTOINCREMENT, + | checked BOOLEAN, + | text TEXT + |); + |""".stripMargin + ) + ctx.executeAction( + """INSERT INTO todo (checked, text) VALUES + |(1, 'Get started with Cask'), + |(0, 'Profit!'); + |""".stripMargin + ) + + import ctx._ + + @transactional + @cask.get("/list/:state") + def list(state: String) = { + val filteredTodos = state match{ + case "all" => run(query[Todo]) + case "active" => run(query[Todo].filter(!_.checked)) + case "completed" => run(query[Todo].filter(_.checked)) + } + upickle.default.write(filteredTodos) + } + + @transactional + @cask.post("/add") + def add(request: cask.Request) = { + val body = new String(request.data.readAllBytes()) + run(query[Todo].insert(_.checked -> lift(false), _.text -> lift(body)).returning(_.id)) + } + + @transactional + @cask.post("/toggle/:index") + def toggle(index: Int) = { + run(query[Todo].filter(_.id == lift(index)).update(p => p.checked -> !p.checked)) + } + + @transactional + @cask.post("/delete/:index") + def delete(index: Int) = { + run(query[Todo].filter(_.id == lift(index)).delete) + } + + initialize() +} + +``` + +- $$$todoDb + +This example demonstrates how to use Cask to write a TodoMVC API server that +persists it's state in a database rather than in memory. We use the +[Quill](http://getquill.io/) database access library to write a `@transactional` +decorator that automatically opens one transaction per call to an endpoint, +ensuring that database queries are properly committed on success or rolled-back +on error. Note that because the default database connector propagates its +transaction context in a thread-local, `@transactional` does not need to pass +the `ctx` object into each endpoint as an additional parameter list, and so we +simply leave it out. + +While this example is specific to Quill, you can easily modify the +`@transactional` decorator to make it work with whatever database access library +you happen to be using. For libraries which need an implicit transaction, it can +be passed into each endpoint function as an additional parameter list as +described in +[Extending Endpoints with Decorators](#extending-endpoints-with-decorators). + +### TodoMVC Full Stack Web + + +The following code snippet is the complete code for a full-stack TodoMVC +implementation: including HTML generation for the web UI via +[Scalatags](https://github.com/lihaoyi/scalatags), Javascript for the +interactivity, static file serving, and database integration via +[Quill](https://github.com/getquill/quill). While slightly long, this example +should give you a tour of all the things you need to know to use Cask. + +Note that this is a "boring" server-side-rendered webapp with Ajax interactions, +without any complex front-end frameworks or libraries: it's purpose is to +demonstrate a simple working web application of using Cask end-to-end, which you +can build upon to create your own Cask web application architected however you +would like. + +```scala +import cask.internal.Router +import com.typesafe.config.ConfigFactory +import io.getquill.{SnakeCase, SqliteJdbcContext} +import scalatags.Text.all._ +import scalatags.Text.tags2 +object Server extends cask.MainRoutes{ + val tmpDb = java.nio.file.Files.createTempDirectory("todo-cask-sqlite") + + object ctx extends SqliteJdbcContext( + SnakeCase, + ConfigFactory.parseString( + s"""{"driverClassName":"org.sqlite.JDBC","jdbcUrl":"jdbc:sqlite:$tmpDb/file.db"}""" + ) + ) + + class transactional extends cask.Decorator{ + class TransactionFailed(val value: Router.Result.Error) extends Exception + def wrapFunction(pctx: cask.ParamContext, delegate: Delegate): Returned = { + try ctx.transaction( + delegate(Map()) match{ + case Router.Result.Success(t) => Router.Result.Success(t) + case e: Router.Result.Error => throw new TransactionFailed(e) + } + ) + catch{case e: TransactionFailed => e.value} + } + } + + case class Todo(id: Int, checked: Boolean, text: String) + + ctx.executeAction( + """CREATE TABLE todo ( + | id INTEGER PRIMARY KEY AUTOINCREMENT, + | checked BOOLEAN, + | text TEXT + |); + |""".stripMargin + ) + ctx.executeAction( + """INSERT INTO todo (checked, text) VALUES + |(1, 'Get started with Cask'), + |(0, 'Profit!'); + |""".stripMargin + ) + + import ctx._ + + @transactional + @cask.post("/list/:state") + def list(state: String) = renderBody(state).render + + @transactional + @cask.post("/add/:state") + def add(state: String, request: cask.Request) = { + val body = new String(request.data.readAllBytes()) + run(query[Todo].insert(_.checked -> lift(false), _.text -> lift(body)).returning(_.id)) + renderBody(state).render + } + + @transactional + @cask.post("/delete/:state/:index") + def delete(state: String, index: Int) = { + run(query[Todo].filter(_.id == lift(index)).delete) + renderBody(state).render + } + + @transactional + @cask.post("/toggle/:state/:index") + def toggle(state: String, index: Int) = { + run(query[Todo].filter(_.id == lift(index)).update(p => p.checked -> !p.checked)) + renderBody(state).render + } + + @transactional + @cask.post("/clear-completed/:state") + def clearCompleted(state: String) = { + run(query[Todo].filter(_.checked).delete) + renderBody(state).render + } + + @transactional + @cask.post("/toggle-all/:state") + def toggleAll(state: String) = { + val next = run(query[Todo].filter(_.checked).size) != 0 + run(query[Todo].update(_.checked -> !lift(next))) + renderBody(state).render + } + + def renderBody(state: String) = { + val filteredTodos = state match{ + case "all" => run(query[Todo]).sortBy(-_.id) + case "active" => run(query[Todo].filter(!_.checked)).sortBy(-_.id) + case "completed" => run(query[Todo].filter(_.checked)).sortBy(-_.id) + } + frag( + header(cls := "header", + h1("todos"), + input(cls := "new-todo", placeholder := "What needs to be done?", autofocus := "") + ), + tags2.section(cls := "main", + input( + id := "toggle-all", + cls := "toggle-all", + `type` := "checkbox", + if (run(query[Todo].filter(_.checked).size != 0)) checked else () + ), + label(`for` := "toggle-all","Mark all as complete"), + ul(cls := "todo-list", + for(todo <- filteredTodos) yield li( + if (todo.checked) cls := "completed" else (), + div(cls := "view", + input( + cls := "toggle", + `type` := "checkbox", + if (todo.checked) checked else (), + data("todo-index") := todo.id + ), + label(todo.text), + button(cls := "destroy", data("todo-index") := todo.id) + ), + input(cls := "edit", value := todo.text) + ) + ) + ), + footer(cls := "footer", + span(cls := "todo-count", + strong(run(query[Todo].filter(!_.checked).size).toInt), + " items left" + ), + ul(cls := "filters", + li(cls := "todo-all", + a(if (state == "all") cls := "selected" else (), "All") + ), + li(cls := "todo-active", + a(if (state == "active") cls := "selected" else (), "Active") + ), + li(cls := "todo-completed", + a(if (state == "completed") cls := "selected" else (), "Completed") + ) + ), + button(cls := "clear-completed","Clear completed") + ) + ) + } + + @transactional + @cask.get("/") + def index() = { + cask.Response( + "<!doctype html>" + html(lang := "en", + head( + meta(charset := "utf-8"), + meta(name := "viewport", content := "width=device-width, initial-scale=1"), + tags2.title("Template • TodoMVC"), + link(rel := "stylesheet", href := "/static/index.css") + ), + body( + tags2.section(cls := "todoapp", renderBody("all")), + footer(cls := "info", + p("Double-click to edit a todo"), + p("Created by ", + a(href := "http://todomvc.com","Li Haoyi") + ), + p("Part of ", + a(href := "http://todomvc.com","TodoMVC") + ) + ), + script(src := "/static/app.js") + ) + ) + ) + } + + @cask.static("/static") + def static() = "example/todo/resources/todo" + + initialize() +} +``` + +- $$$todo + +Main Customization +------------------ + +Apart from the code used to configure and define your routes and endpoints, Cask +also allows global configuration for things that apply to the entire web server. +This can be done by overriding the following methods on `cask.Main` or +`cask.MainRoutes`: + +### def debugMode: Boolean = true + +Makes the Cask report verbose error messages and stack traces if an endpoint +fails; useful for debugging, should be disabled for production. + +### def main + +The cask program entrypoint. By default just spins up a webserver, but you can +override it to do whatever you like before or after the webserver runs. + +### def defaultHandler + +Cask is built on top of the [Undertow](http://undertow.io/) web server. If you +need some low-level functionality not exposed by the Cask API, you can override +`defaultHandler` to make use of Undertow's own +[handler API](http://undertow.io/undertow-docs/undertow-docs-2.0.0/index.html#built-in-handlers) +for customizing your webserver. This allows for things that Cask itself doesn't +internally support: asynchronous requests & response, +[Websockets](http://undertow.io/undertow-docs/undertow-docs-2.0.0/index.html#websockets), +etc. + +### def port: Int = 8080, def host: String = "localhost" + +The host & port to attach your webserver to. + +### def handleNotFound + +The response to serve when the incoming request does not match any of the routes +or endpoints; defaults to a typical 404 + +### def handleEndpointError + +The response to serve when the incoming request matches a route and endpoint, +but then fails for other reasons. Defaults to 400 for mismatched or invalid +endpoint arguments and 500 for exceptions in the endpoint body, and provides +useful stack traces or metadata for debugging if `debugMode = true`. + +### def mainDecorators + +Any `cask.Decorator`s that you want to apply to all routes and all endpoints in +the entire web application
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