View for album

Db.fs

@@ -0,0 +1,36 @@
+module Db
+
+open FSharp.Data.Sql
+
+type Sql = 
+    SqlDataProvider< 
+        "Server=(LocalDb)\\v11.0;Database=FreyaMusicStore;Trusted_Connection=True;MultipleActiveResultSets=true", 
+        DatabaseVendor=Common.DatabaseProviderTypes.MSSQLSERVER >
+
+type DbContext = Sql.dataContext
+type Album = DbContext.``[dbo].[Albums]Entity``
+type Genre = DbContext.``[dbo].[Genres]Entity``
+type AlbumDetails = DbContext.``[dbo].[AlbumDetails]Entity``
+
+let getContext() = Sql.GetDataContext()
+
+let firstOrNone s = s |> Seq.tryFind (fun _ -> true)
+
+let getGenres (ctx : DbContext) : Genre list = 
+    ctx.``[dbo].[Genres]`` |> Seq.toList
+
+let getAlbumsForGenre genreName (ctx : DbContext) : Album list = 
+    query { 
+        for album in ctx.``[dbo].[Albums]`` do
+            join genre in ctx.``[dbo].[Genres]`` on (album.GenreId = genre.GenreId)
+            where (genre.Name = genreName)
+            select album
+    }
+    |> Seq.toList
+
+let getAlbumDetails id (ctx : DbContext) : AlbumDetails option = 
+    query { 
+        for album in ctx.``[dbo].[AlbumDetails]`` do
+            where (album.AlbumId = id)
+            select album
+    } |> firstOrNone

FreyaMusicStore.fsproj

@@ -54,16 +54,30 @@
   </Choose>
   <Import Project="$(FSharpTargetsPath)" />
   <ItemGroup>
+    <Compile Include="Db.fs" />
+    <Compile Include="View.fs" />
     <Compile Include="Program.fs" />
     <None Include="index.cshtml">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
     <None Include="home.cshtml">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
+    <None Include="album.cshtml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Include="genres.cshtml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Include="genre.cshtml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
     <Content Include="Site.css">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <None Include="placeholder.gif">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
     <None Include="App.config" />
     <Content Include="packages.config" />
   </ItemGroup>
@@ -148,6 +162,10 @@
       <HintPath>packages\FSharp.Core.3.1.2.1\lib\net40\FSharp.Core.dll</HintPath>
       <Private>True</Private>
     </Reference>
+    <Reference Include="FSharp.Data.SqlProvider">
+      <HintPath>packages\SQLProvider.0.0.9-alpha\lib\net40\FSharp.Data.SqlProvider.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
     <Reference Include="Hekate">
       <HintPath>packages\Hekate.1.0.0\lib\net40\Hekate.dll</HintPath>
       <Private>True</Private>
@@ -175,6 +193,7 @@
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
+    <Reference Include="System.Data" />
     <Reference Include="System.Numerics" />
     <Reference Include="System.Web.Razor">
       <HintPath>packages\Microsoft.AspNet.Razor.3.0.0\lib\net45\System.Web.Razor.dll</HintPath>

Program.fs

@@ -54,18 +54,33 @@ let common =
         using http
         mediaTypesSupported commonMediaTypes }
 
-let getAlbum =
+let albumId =
     freya {
         let! id = Freya.getLensPartial (Route.atom "id")
-        return! write ("home", {Greeting = sprintf "Album no %d" (Int32.Parse id.Value) })
+        match Int32.TryParse id.Value with
+        | true, id -> return Some id
+        | _ -> return None
+    }
+
+let getAlbum =
+    freya {
+        let! id = albumId
+        let ctx = Db.getContext()
+        let album = Db.getAlbumDetails id.Value ctx |> Option.get |> View.toAlbum
+        return! write ("album", album)
     }
 
 let albumMalformed = 
     freya {
-        let! id = Freya.getLensPartial (Route.atom "id")
-        match Int32.TryParse id.Value with
-        | true, _ -> return false
-        | _ -> return true
+        let! id = albumId
+        return Option.isNone id
+    }
+
+let albumExists = 
+    freya {
+        let! id = albumId
+        let ctx = Db.getContext()
+        return Db.getAlbumDetails id.Value ctx |> Option.isSome
     }
 
 let getGenre =
@@ -84,6 +99,7 @@ let album =
     freyaMachine {
         including common
         malformed albumMalformed
+        exists albumExists
         methodsSupported ( freya { return [ GET ] } ) 
         handleOk (fun _ -> getAlbum) } |> FreyaMachine.toPipeline
 
@@ -123,6 +139,8 @@ let resource key =
 let private cssContent =
     resource "Site.css"
 
+let private placeholderContent =
+    resource "placeholder.gif"
 
 let private firstNegotiatedOrElse def =
     function | Negotiated (x :: _) -> x
@@ -143,15 +161,25 @@ let private getContent content n =
 let private getCss =
     getContent cssContent
 
+let private getPlaceholder = 
+    getContent placeholderContent
+
 let private css =
     freyaMachine {
         including defaults
         mediaTypesSupported (Freya.init [ MediaType.Css ])
         handleOk getCss } |> FreyaMachine.toPipeline
 
+let private placeholder =
+    freyaMachine {
+        including defaults
+        mediaTypesSupported (Freya.init [ MediaType.Parse "image/gif" ])
+        handleOk getPlaceholder } |> FreyaMachine.toPipeline
+
 let musicStore =
     freyaRouter {
         resource (UriTemplate.Parse "/Site.css") css
+        resource (UriTemplate.Parse "/placeholder.gif") placeholder
         resource (UriTemplate.Parse "/") home
         resource (UriTemplate.Parse "/album/{id}") album
         resource (UriTemplate.Parse "/genres") genres

View.fs

@@ -0,0 +1,17 @@
+module View
+
+type AlbumDetails = {
+    Title : string
+    AlbumArtUrl : string
+    Price : decimal
+    Artist : string
+    Genre : string
+}
+
+let toAlbum (a: Db.AlbumDetails) = {
+    Title = a.Title
+    AlbumArtUrl = a.AlbumArtUrl
+    Price = a.Price
+    Artist = a.Artist
+    Genre = a.Genre
+}

album.cshtml

@@ -4,4 +4,24 @@
 
 @section Main
 {
+<h2>@Model.Title</h2>
+
+<p>
+    <img alt="@Model.Title" src="@Model.AlbumArtUrl" />
+</p>
+
+<div id="album-details">
+    <p>
+        <em>Genre:</em>
+        @Model.Genre
+    </p>
+    <p>
+        <em>Artist:</em>
+        @Model.Artist
+    </p>
+    <p>
+        <em>Price:</em>
+        @String.Format("{0:F}", Model.Price)
+    </p>
+</div>
 }

packages.config

@@ -27,4 +27,5 @@
   <package id="Microsoft.Owin.Hosting" version="3.0.1" targetFramework="net451" />
   <package id="Owin" version="1.0" targetFramework="net451" />
   <package id="RazorEngine" version="3.7.0" targetFramework="net451" />
+  <package id="SQLProvider" version="0.0.9-alpha" targetFramework="net451" />
 </packages>