# JobHandlerContract
> Tracon documentation. Tracon is a .NET package family that adds a control
> plane on Microsoft Agent Framework, published as NuGet packages that run
> inside your own ASP.NET Core application.
>
> Page: https://tracon.dev/api/tracon.testing.contracts.scheduling.jobhandlercontract/
> Summary: JobHandlerContract: Behavior tests for the IJobHandler at-least-once contract: a handler must not reprocess an item already reported, and must observe cancellation between items.
Namespace Tracon.Testing.Contracts.Scheduling · Assembly Tracon.Testing.Contracts.Xunit.dll
Behavior tests for the [IJobHandler](/api/tracon.ijobhandler/) at-least-once contract:
a handler must not reprocess an item already reported, and must observe
cancellation between items.
```csharp
public abstract class JobHandlerContract : IAsyncLifetime, IAsyncDisposable
```
- Inheritance
- object ← JobHandlerContract
- Implements
- IAsyncLifetime, IAsyncDisposable
- Inherited Members
- object.GetType(), object.MemberwiseClone(), object.ToString(), object.Equals(object?), object.Equals(object?, object?), object.ReferenceEquals(object?, object?), object.GetHashCode()
## Constructors
### JobHandlerContract\(\)
```csharp
protected JobHandlerContract()
```
## Properties
### Handler
The handler under test.
```csharp
protected IJobHandler Handler { get; }
```
#### Property Value
[IJobHandler](/api/tracon.ijobhandler/)
### HandlerKey
The handler key the job records this contract builds carry. Override
when the handler under test needs its real key (a built-in one from
[JobHandlerKeys](/api/tracon.jobhandlerkeys/), or the consumer's own); the value never
reaches dispatch here, because the contract calls the handler directly.
```csharp
protected virtual string HandlerKey { get; }
```
#### Property Value
[string](https://learn.microsoft.com/dotnet/api/system.string)
### JobId
The job identifier shared by every [JobContext](/api/tracon.jobcontext/) built
during this instance's tests. A handler that keys other state by job id
(an eval run record, for example) can create that state against this
value inside [JobHandlerContract.CreateHandlerAsync](/api/tracon.testing.contracts.scheduling.jobhandlercontract/#Tracon_Testing_Contracts_Scheduling_JobHandlerContract_CreateHandlerAsync).
```csharp
protected Guid JobId { get; }
```
#### Property Value
[Guid](https://learn.microsoft.com/dotnet/api/system.guid)
## Methods
### Cancellation\_is\_observed\_between\_items\(\)
```csharp
[Fact]
public Task Cancellation_is_observed_between_items()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Completed\_items\_are\_not\_processed\_again\(\)
```csharp
[Fact]
public Task Completed_items_are_not_processed_again()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### CreateHandlerAsync\(\)
Creates the handler under test, performing whatever async setup it
needs (an eval suite and run record, a workflow registration, and
so on).
```csharp
protected abstract ValueTask CreateHandlerAsync()
```
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask\-1)<[IJobHandler](/api/tracon.ijobhandler/)\>
### CreateItem\(int, JobItemStatus\)
Creates one job item the handler under test can process.
```csharp
protected abstract JobItemRecord CreateItem(int sequence, JobItemStatus status)
```
#### Parameters
`sequence` [int](https://learn.microsoft.com/dotnet/api/system.int32)
The item's position within the job.
`status` [JobItemStatus](/api/tracon.jobitemstatus/)
The item's starting status.
#### Returns
[JobItemRecord](/api/tracon.jobitemrecord/)
### CreateJob\(IReadOnlyList\)
Builds the job record wrapping `items`. Override to
set a specific target name or payload the handler under test needs.
```csharp
protected virtual JobRecord CreateJob(IReadOnlyList items)
```
#### Parameters
`items` [IReadOnlyList](https://learn.microsoft.com/dotnet/api/system.collections.generic.ireadonlylist\-1)<[JobItemRecord](/api/tracon.jobitemrecord/)\>
#### Returns
[JobRecord](/api/tracon.jobrecord/)
### DisposeAsync\(\)
```csharp
public ValueTask DisposeAsync()
```
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask)
### InitializeAsync\(\)
Called immediately after the class has been created, before it is used.
```csharp
public ValueTask InitializeAsync()
```
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask)
### Only\_pending\_items\_are\_processed\_on\_a\_retry\(\)
```csharp
[Fact]
public Task Only_pending_items_are_processed_on_a_retry()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)