JSON support in REST data service – Part I

In Smart Office 10.2.1.0.367 HF38 there is support for JSON when calling a REST data service from a Mashup. In this blog post I’m going to use a fake online REST service to demonstrate how it’s done.

The response data from the REST service call can be converted into a DataItem hierarchy or as a JSON string. This example will fetch a listing of users from the service and present them in a Mashup ListView and in a TextBox as a JSON string, side-by-side.

Mashup_REST_JSON_LIST

The Mashup XAML syntax will be the same as before when doing a REST service call. All you need to do now is set the REST.AcceptHeader parameter to application/json.
The REST.OutputType determines if the data response is available to the Mashup as an object hierarchy or as a JSON string. Use the value ‘DataItem’ to get DataItem hierarchy or set ‘application/json’ for a JSON string. If REST.OutputType is not set the default will be a DataItem hierarchy.

<mashup:DataListPanel.DataService>
    <mashup:DataService Type="REST">
        <mashup:DataService.Operations>
            <mashup:DataOperation Name="List">
                <mashup:DataParameter Key="REST.BaseAddress" Value="https://jsonplaceholder.typicode.com/users/" />
                <mashup:DataParameter Key="REST.OutputType" Value="DataItem" />
                <mashup:DataParameter Key="REST.AcceptHeader" Value="application/json" />
            </mashup:DataOperation>
        </mashup:DataService.Operations>
    </mashup:DataService>
</mashup:DataListPanel.DataService>

To set the first column in the ListView to the company name use the binding below.

DisplayMemberBinding="{Binding [company].[name]}"

To access the JSON string when that is set as output type simply bind to ‘json’.

Text="{Binding [json]}"

Here is the complete Mashup code if you would like to try it out.

<Grid Margin="15,10,15,15" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:ui="clr-namespace:Mango.UI.Controls;assembly=Mango.UI" xmlns:mashup="clr-namespace:Mango.UI.Services.Mashup;assembly=Mango.UI" xmlns:m3="clr-namespace:MForms.Mashup;assembly=MForms" xmlns:sys="clr-namespace:System;assembly=mscorlib">
   <Grid.RowDefinitions>
      <RowDefinition Height="1*" />
   </Grid.RowDefinitions>
   <Grid.ColumnDefinitions>
      <ColumnDefinition Width="1*" />
      <ColumnDefinition Width="10" />
      <ColumnDefinition Width="1*" />
   </Grid.ColumnDefinitions>
   <mashup:DataListPanel DockPanel.Dock="Top" Name="UsersList" Grid.Column="0" Grid.Row="0" Grid.RowSpan="3">
      <mashup:DataListPanel.DataService>
         <mashup:DataService Type="REST">
            <mashup:DataService.Operations>
               <mashup:DataOperation Name="List">
                  <mashup:DataParameter Key="REST.BaseAddress" Value="https://jsonplaceholder.typicode.com/users/" />
                  <mashup:DataParameter Key="REST.OutputType" Value="DataItem" />
                  <mashup:DataParameter Key="REST.AcceptHeader" Value="application/json" />
               </mashup:DataOperation>
            </mashup:DataService.Operations>
         </mashup:DataService>
      </mashup:DataListPanel.DataService>
      <mashup:DataListPanel.Events>
         <mashup:Events>
            <mashup:Event SourceEventName="Startup" TargetEventName="List" />
         </mashup:Events>
      </mashup:DataListPanel.Events>
      <DockPanel LastChildFill="False">
         <ListView DockPanel.Dock="Top" Name="ListViewCompany" ItemsSource="{Binding Items}" Style="{DynamicResource styleListView}" ItemContainerStyle="{DynamicResource styleListViewItem}">
            <ListView.View>
               <GridView ColumnHeaderContainerStyle="{DynamicResource styleGridViewColumnHeader}">
                  <GridView.Columns>
                     <GridViewColumn Header="Company" DisplayMemberBinding="{Binding [company].[name]}" />
                     <GridViewColumn Header="City" DisplayMemberBinding="{Binding [address].[city]}" />
                     <GridViewColumn Header="Name" DisplayMemberBinding="{Binding [name]}" />
                     <GridViewColumn Header="Email" DisplayMemberBinding="{Binding [email]}" />
                     <GridViewColumn Header="Longitude" DisplayMemberBinding="{Binding [address].[geo].[lng]}" />
                     <GridViewColumn Header="Longitude" DisplayMemberBinding="{Binding [address].[geo].[lng]}" />
                  </GridView.Columns>
               </GridView>
            </ListView.View>
         </ListView>
      </DockPanel>
   </mashup:DataListPanel>
   <mashup:DataPanel Grid.Row="0" Grid.Column="2" Name="JsonString">
      <mashup:DataPanel.DataService>
         <mashup:DataService Type="REST">
            <mashup:DataService.Operations>
               <mashup:DataOperation Name="List">
                  <mashup:DataParameter Key="REST.BaseAddress" Value="https://jsonplaceholder.typicode.com/users/" />
                  <mashup:DataParameter Key="REST.AcceptHeader" Value="application/json" />
                  <mashup:DataParameter Key="REST.OutputType" Value="application/json" />
               </mashup:DataOperation>
            </mashup:DataService.Operations>
         </mashup:DataService>
      </mashup:DataPanel.DataService>
      <mashup:DataPanel.Events>
         <mashup:Events>
            <mashup:Event SourceEventName="Startup" TargetEventName="List" />
         </mashup:Events>
      </mashup:DataPanel.Events>
      <Grid Margin="10,0,10,0">
         <TextBox Text="{Binding [json]}" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" AcceptsReturn="True" VerticalContentAlignment="Top" TextWrapping="Wrap" />
      </Grid>
   </mashup:DataPanel>
</Grid>

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