Using Steeltoe DiscoveryHttpMessageHandler with FlurlClient

2021-03-08 17:38 BrianM imported from Stackoverflow

I am looking to switch our HttpClients to use Flurl. However, our HttpClient is currently configured to use Service Discovery via Steeltoe. Basically it's doing this in ConfigureServices:

   services.AddHttpClient<IMyClass, MyClass>().AddHttpMessageHandler<DiscoveryHttpMessageHandler>();

DiscoveryHttpMessageHandler is a custom http message handler in the Steeltoe library (https://github.com/SteeltoeOSS)

How do I access the IHttpClientBuilder with Flurl so I can add this same message hander? Or is there another clean way with Flurl to add a custom message handler for every HttpClient/FlurlClient created?

1 answer

answered 2021-03-09 14:22 Todd Menier
There's a few ways to add a custom message handler with Flurl (such as with a custom factory), but since you're already using IHttpClientFactory, I think the easiest path to get what you want (and the one I'd recommend) is to continue injecting HttpClient into your services as you're doing and wrap them with Flurl inside the service:
```
public class MyClass : IMyClass
{
    private readonly IFlurlClient _flurlClient;

    public MyService(HttpClient httpClient) {
        _flurlClient = new FlurlClient(httpClient);
    }
}
```

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Quick Summary

I have managed to code up this output so far

XAML

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition />
    </Grid.ColumnDefinitions>

    <StackPanel Grid.Column="0">
        <DataGrid ItemsSource="{Binding AddressView}">
            
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    public string Name { get; set; }

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        people.Add(new PersonModel { Id = 2, Name = "Max" });
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AddressModel

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    public string Address { get; set; }
    public int PersonId { get; set; }

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ViewModel

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        RefreshData();
    }

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    private ObservableCollection<PersonModel> _personModels;
    public ObservableCollection<PersonModel> PersonModels
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        AddressModels = CopyOfAddressModel.GetAddressModels();

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My current goal is to filter the Address View on the left hand side of the MainWindow via the the ListView on the right hand side.

For example: Selected Id from the ListView is 1. Then filter the Address View in the DataGrid where PersonId = 1.

What I have tried

I added a Filter method and a Search property:

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private bool Filter(AddressModel address)
{
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}

private int search;
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{
    get { return search; }
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AddressView.Filter = new Predicate<object>(o => Filter(o as AddressModel));

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