How to create document history for status changes

• Register two functions in IWorkflowActionProvider:
  • The first function (WriteTransitionHistory) is for making a list. Use the process Instance.IdentityIds to form a list of potential approvers.
  • The second function (UpdateTransitionHistory) is for adding current action into the table of history changes.
• Add these functions into "Implementation" and "Pre-Execute Implementation" units for each Activity that defines the document status.
• Subscribe to ProcessStatusChanged event in WorkflowRuntime. In the command handler, do the following:
  • Delete empty history fields (if exists).
  • Call PreExecuteFromCurrentActivity method in WorkflowRuntime.

Example of method for PreExecute Implementation

public static void WriteTransitionHistory(ProcessInstance processInstance, string parameter)
{
    if (processInstance.IdentityIds == null)
        return;
    var currentstate = WorkflowInit.Runtime.GetLocalizedStateName(processInstance.ProcessId, processInstance.CurrentState);
    var nextState = WorkflowInit.Runtime.GetLocalizedStateName(processInstance.ProcessId, processInstance.ExecutedActivityState);
    var command = WorkflowInit.Runtime.GetLocalizedCommandName(processInstance.ProcessId, processInstance.CurrentCommand);
    using (var context = new DataModelDataContext())
    {
        GetEmployeesString(processInstance.IdentityIds, context);
        var historyItem = new DocumentTransitionHistory
                              {
                                  Id = Guid.NewGuid(),
                                  AllowedToEmployeeNames = GetEmployeesString(processInstance.IdentityIds, context),
                                  DestinationState = nextState,
                                  DocumentId = processInstance.ProcessId,
                                  InitialState = currentstate,
                                  Command = command
                              };
        context.DocumentTransitionHistories.InsertOnSubmit(historyItem);
        context.SubmitChanges();
    }
}

Example of method for Implementation

public static void UpdateTransitionHistory(ProcessInstance processInstance, string parameter)
{
    var currentstate = WorkflowInit.Runtime.GetLocalizedStateName(processInstance.ProcessId, processInstance.CurrentState);
    var nextState = WorkflowInit.Runtime.GetLocalizedStateName(processInstance.ProcessId, processInstance.ExecutedActivityState);
    var command = WorkflowInit.Runtime.GetLocalizedCommandName(processInstance.ProcessId, processInstance.CurrentCommand);
    using (var context = new DataModelDataContext())
    {
        var historyItem =
            context.DocumentTransitionHistories.FirstOrDefault(
                h => h.DocumentId == processInstance.ProcessId && !h.TransitionTime.HasValue &&
                     h.InitialState == currentstate && h.DestinationState == nextState);
        if (historyItem == null)
        {
            historyItem = new DocumentTransitionHistory
            {
                Id = Guid.NewGuid(),
                AllowedToEmployeeNames = string.Empty,
                DestinationState = nextState,
                DocumentId = processInstance.ProcessId,
                InitialState = currentstate
            };
            context.DocumentTransitionHistories.InsertOnSubmit(historyItem);
        }
        historyItem.Command = command;
        historyItem.TransitionTime = DateTime.Now;
        if (string.IsNullOrWhiteSpace(processInstance.IdentityId))
            historyItem.EmployeeId = null;
        else
            historyItem.EmployeeId = new Guid(processInstance.IdentityId);
        context.SubmitChanges();
    }
}