Add basic auth example.

examples/end-to-end/app/Page/Test/BasicAuth.elm

@@ -0,0 +1,134 @@
+module Page.Test.BasicAuth exposing (Data, Model, Msg, page)
+
+import Base64
+import DataSource exposing (DataSource)
+import Head
+import Html.Styled exposing (div, text)
+import Page exposing (Page, PageWithState, StaticPayload)
+import Pages.PageUrl exposing (PageUrl)
+import Server.Request as Request exposing (Request)
+import Server.Response as Response exposing (Response)
+import Shared
+import View exposing (View)
+
+
+type alias Model =
+    {}
+
+
+type alias Msg =
+    ()
+
+
+type alias RouteParams =
+    {}
+
+
+page : Page RouteParams Data
+page =
+    Page.serverRender
+        { head = head
+        , data = data
+        }
+        |> Page.buildNoState { view = view }
+
+
+type alias Data =
+    { greeting : String
+    }
+
+
+data : RouteParams -> Request (DataSource (Response Data))
+data routeParams =
+    withBasicAuth
+        (\{ username, password } ->
+            (username == "asdf" && password == "qwer")
+                |> DataSource.succeed
+        )
+        (Data "Login success!"
+            |> Response.render
+            |> DataSource.succeed
+        )
+
+
+head :
+    StaticPayload Data RouteParams
+    -> List Head.Tag
+head static =
+    []
+
+
+view :
+    Maybe PageUrl
+    -> Shared.Model
+    -> StaticPayload Data RouteParams
+    -> View Msg
+view maybeUrl sharedModel static =
+    { title = "Basic Auth Test"
+    , body =
+        [ text "Basic Auth Test"
+        , div []
+            [ text static.data.greeting
+            ]
+        ]
+    }
+
+
+parseAuth : String -> Maybe { username : String, password : String }
+parseAuth base64Auth =
+    case
+        base64Auth
+            |> String.dropLeft 6
+            |> Base64.toString
+            |> Maybe.map (String.split ":")
+    of
+        Just [ username, password ] ->
+            Just
+                { username = username
+                , password = password
+                }
+
+        _ ->
+            Nothing
+
+
+withBasicAuth :
+    ({ username : String, password : String } -> DataSource Bool)
+    -> DataSource (Response data)
+    -> Request (DataSource (Response data))
+withBasicAuth checkAuth successResponse =
+    Request.oneOf
+        [ Request.expectHeader "authorization"
+            |> Request.map
+                (\base64Auth ->
+                    case parseAuth base64Auth of
+                        Just userPass ->
+                            checkAuth userPass
+                                |> DataSource.andThen
+                                    (\authSucceeded ->
+                                        if authSucceeded then
+                                            successResponse
+
+                                        else
+                                            requireBasicAuth |> DataSource.succeed
+                                    )
+
+                        Nothing ->
+                            requireBasicAuth
+                                |> DataSource.succeed
+                )
+        , requireBasicAuth
+            |> DataSource.succeed
+            |> Request.succeed
+        ]
+
+
+requireBasicAuth : Response data
+requireBasicAuth =
+    Response.customResponse
+        { headers = []
+        , body = Nothing
+        , statusCode = 401
+        , isBase64Encoded = False
+        }
+        |> Response.withHeader "WWW-Authenticate" "Basic"