code: func (c *WorkItemLinkController) Create(ctx *app.CreateWorkItemLinkContext) error {
  	currentUserIdentityID, err := login.ContextIdentity(ctx)
  	if err != nil {
  		return jsonapi.JSONErrorResponse(ctx, errors.NewUnauthorizedError(err.Error()))
  	}
  	modelLink, err := ConvertLinkToModel(app.WorkItemLinkSingle{
  		Data: ctx.Payload.Data,
  	})
  	if err != nil {
  		return jsonapi.JSONErrorResponse(ctx, err)
  	}
  	var createdModelLink *link.WorkItemLink
  	err = application.Transactional(c.db, func(appl application.Application) error {
  		var err error
  		createdModelLink, err = appl.WorkItemLinks().Create(ctx.Context, modelLink.SourceID, modelLink.TargetID, modelLink.LinkTypeID, *currentUserIdentityID)
  		return err
  	})
  	if err != nil {
  		return jsonapi.JSONErrorResponse(ctx, err)
  	}
  	// convert from model to rest representation
  	createdAppLink := ConvertLinkFromModel(ctx.Request, *createdModelLink)
  	if err := enrichLinkSingle(ctx.Context, c.db, ctx.Request, &createdAppLink); err != nil {
  		return jsonapi.JSONErrorResponse(ctx, err)
  	}
  	ctx.ResponseWriter.Header().Set("Location", app.WorkItemLinkHref(createdAppLink.Data.ID))
  	return ctx.Created(&createdAppLink)
  }
docs: // Create runs the create action.