/// <summary>
/// Retrieves the page by its id.
/// </summary>
/// <param name="id">The id of the page</param>
/// <returns>A <see cref="PageViewModel"/> for the page.</returns>
/// <exception cref="DatabaseException">An databaseerror occurred while getting the page.</exception>
public PageViewModel GetById(int id, bool loadContent = false)
{
try
{
PageViewModel pageModel = _pageViewModelCache.Get(id);
if (pageModel != null)
{
return(pageModel);
}
else
{
Page page = Repository.GetPageById(id);
if (page == null)
{
return(null);
}
else
{
// If object caching is enabled, ignore the "loadcontent" parameter as the cache will be
// used on the second call anyway, so performance isn't an issue.
if (ApplicationSettings.UseObjectCache)
{
pageModel = new PageViewModel(Repository.GetLatestPageContent(page.Id), _markupConverter);
}
else
{
if (loadContent)
{
pageModel = new PageViewModel(Repository.GetLatestPageContent(page.Id), _markupConverter);
}
else
{
pageModel = new PageViewModel(page);
}
}
_pageViewModelCache.Add(id, pageModel);
return(pageModel);
}
}
}
catch (DatabaseException ex)
{
throw new DatabaseException(ex, "An error occurred getting the page with id '{0}' from the database", id);
}
}
/// <summary>
/// Compares a page version to the previous version.
/// </summary>
/// <param name="mainVersionId">The id of the version to compare</param>
/// <returns>Returns a IEnumerable of two versions, where the 2nd item is the previous version.
/// If the current version is 1, or a previous version cannot be found, then the 2nd item will be null.</returns>
/// <exception cref="HistoryException">An database error occurred while comparing the two versions.</exception>
public IEnumerable <PageViewModel> CompareVersions(Guid mainVersionId)
{
try
{
List <PageViewModel> versions = new List <PageViewModel>();
PageContent mainContent = Repository.GetPageContentById(mainVersionId);
versions.Add(new PageViewModel(mainContent, _markupConverter));
if (mainContent.VersionNumber == 1)
{
versions.Add(null);
}
else
{
PageViewModel model = _pageViewModelCache.Get(mainContent.Page.Id, mainContent.VersionNumber - 1);
if (model == null)
{
PageContent previousContent = Repository.GetPageContentByPageIdAndVersionNumber(mainContent.Page.Id, mainContent.VersionNumber - 1);
if (previousContent == null)
{
model = null;
}
else
{
model = new PageViewModel(previousContent, _markupConverter);
_pageViewModelCache.Add(mainContent.Page.Id, mainContent.VersionNumber - 1, model);
}
}
versions.Add(model);
}
return(versions);
}
catch (ArgumentNullException ex)
{
throw new HistoryException(ex, "An ArgumentNullException occurred comparing the version history for version id {0}", mainVersionId);
}
catch (DatabaseException ex)
{
throw new HistoryException(ex, "A HibernateException occurred comparing the version history for version id {0}", mainVersionId);
}
}