private void RefreshPreview(EpubPublishUiSettings newSettings)
{
// We have seen some exceptions thrown during refresh that cause a pretty yellow
// dialog box pop up informing the user, e.g., that the program couldn't find
// "api/publish/epub/updatePreview". Rather than confuse the user, we catch such
// exceptions here and retry a limited number of times.
// See https://issues.bloomlibrary.org/youtrack/issue/BL-6763.
Exception exception = null;
for (int i = 0; i < 3; ++i)
{
try
{
if (UpdatePreview(newSettings, true))
{
_webSocketServer.SendString(kWebsocketContext, kWebsocketEventId_epubReady, _previewSrc);
}
return;
}
catch (Exception e)
{
exception = e; // the original stack trace is rather important for post mortem debugging!
}
}
// Notify the user gently that updating the ePUB preview failed.
NonFatalProblem.Report(ModalIf.None, PassiveIf.All, "Something went wrong while making the ePUB preview.",
"Updating the ePUB preview failed: " + exception.Message, exception);
}
public void GetEpubSettingsForCurrentBook(EpubPublishUiSettings epubPublishUiSettings)
{
var info = _bookSelection.CurrentSelection.BookInfo;
epubPublishUiSettings.howToPublishImageDescriptions = info.MetaData.Epub_HowToPublishImageDescriptions;
epubPublishUiSettings.removeFontSizes = info.MetaData.Epub_RemoveFontSizes;
}
public void UpdateAndSave(EpubPublishUiSettings newSettings, string path, bool force, WebSocketProgress progress = null)
{
bool succeeded;
do
{
lock (this)
{
succeeded = UpdatePreview(newSettings, force, progress);
if (succeeded)
{
EpubMaker.SaveEpub(path, _progress);
_webSocketServer.SendString(kWebsocketContext, kWebsocketEventId_epubReady, _previewSrc);
}
}
} while (!succeeded && !EpubMaker.AbortRequested); // try until we get a complete epub, not interrupted by user changing something.
}
public bool UpdatePreview(EpubPublishUiSettings newSettings, bool force, WebSocketProgress progress = null)
{
_progress = progress ?? _standardProgress.WithL10NPrefix("PublishTab.Epub.");
if (Program.RunningOnUiThread)
{
// There's some stuff inside this lock that has to run on the UI thread.
// If we lock the UI thread here, we can deadlock the whole program.
throw new ApplicationException(@"Must not attempt to make epubs on UI thread...will produce deadlocks");
}
lock (_epubMakerLock)
{
if (EpubMaker != null)
{
EpubMaker.AbortRequested = false;
}
_stagingEpub = true;
}
// For some unknown reason, if the accessibility window is showing, some of the browser navigation
// that is needed to accurately determine which content is visible simply doesn't happen.
// It would be disconcerting if it popped to the top after we close it and reopen it.
// So, we just close the window if it is showing when we do this. See BL-7807.
// Except that opening the Ace Checker tab invokes this code path in a way that works without the
// deadlock (or whatever causes the failure). This call can be detected by the progress argument not
// being null. The Refresh button on the AccessibilityCheckWindow also uses this code path in the
// same way, so the next two lines also allow that Refresh button to work. See BL-9341 for why
// the original fix is inadequate.
if (progress == null)
{
AccessibilityChecker.AccessibilityCheckWindow.StaticClose();
}
try
{
_webSocketServer.SendString(kWebsocketContext, "startingEbookCreation", _previewSrc);
var htmlPath = _bookSelection.CurrentSelection.GetPathHtmlFile();
var newVersion = Book.Book.ComputeHashForAllBookRelatedFiles(htmlPath);
bool previewIsAlreadyCurrent;
lock (_epubMakerLock)
{
previewIsAlreadyCurrent = _desiredEpubSettings == newSettings && EpubMaker != null && newVersion == _bookVersion &&
!EpubMaker.AbortRequested && !force;
}
if (previewIsAlreadyCurrent)
{
SaveAsEpub(); // just in case there's a race condition where we haven't already saved it.
return(true); // preview is already up to date.
}
_desiredEpubSettings = newSettings;
// clear the obsolete preview, if any; this also ensures that when the new one gets done,
// we will really be changing the src attr in the preview iframe so the display will update.
_webSocketServer.SendEvent(kWebsocketContext, kWebsocketEventId_epubReady);
_bookVersion = newVersion;
ReportProgress(LocalizationManager.GetString("PublishTab.Epub.PreparingPreview", "Preparing Preview"));
// This three-tries loop is an attempt to recover from a weird state the system sometimes gets into
// where a browser won't navigate to a temporary page that the EpubMaker uses. I'm not sure it actually
// helps, once the system gets into this state even a brand new browser seems to have the same problem.
// Usually there will be no exception, and the loop breaks at the end of the first iteration.
for (int i = 0; i < 3; i++)
{
try
{
if (!PublishHelper.InPublishTab)
{
return(false);
}
_previewSrc = UpdateEpubControlContent();
}
catch (ApplicationException ex)
{
if (i >= 2)
{
throw;
}
ReportProgress("Something went wrong, trying again");
continue;
}
break; // normal case, no exception
}
lock (_epubMakerLock)
{
if (EpubMaker.AbortRequested)
{
return(false); // the code that set the abort flag will request a new preview.
}
}
}
finally
{
lock (_epubMakerLock)
{
_stagingEpub = false;
}
}
// Do pending save if the user requested it while the preview was still in progress.
SaveAsEpub();
ReportProgress(LocalizationManager.GetString("PublishTab.Epub.Done", "Done"));
return(true);
}
public bool UpdatePreview(EpubPublishUiSettings newSettings, bool force, WebSocketProgress progress = null)
{
_progress = progress ?? _standardProgress.WithL10NPrefix("PublishTab.Epub.");
if (Program.RunningOnUiThread)
{
// There's some stuff inside this lock that has to run on the UI thread.
// If we lock the UI thread here, we can deadlock the whole program.
throw new ApplicationException(@"Must not attempt to make epubs on UI thread...will produce deadlocks");
}
lock (_epubMakerLock)
{
if (EpubMaker != null)
{
EpubMaker.AbortRequested = false;
}
_stagingEpub = true;
}
try
{
_webSocketServer.SendString(kWebsocketContext, "startingEbookCreation", _previewSrc);
var htmlPath = _bookSelection.CurrentSelection.GetPathHtmlFile();
var newVersion = Book.Book.MakeVersionCode(File.ReadAllText(htmlPath), htmlPath);
bool previewIsAlreadyCurrent;
lock (_epubMakerLock)
{
previewIsAlreadyCurrent = _desiredEpubSettings == newSettings && EpubMaker != null && newVersion == _bookVersion &&
!EpubMaker.AbortRequested && !force;
}
if (previewIsAlreadyCurrent)
{
SaveAsEpub(); // just in case there's a race condition where we haven't already saved it.
return(true); // preview is already up to date.
}
_desiredEpubSettings = newSettings;
// clear the obsolete preview, if any; this also ensures that when the new one gets done,
// we will really be changing the src attr in the preview iframe so the display will update.
_webSocketServer.SendEvent(kWebsocketContext, kWebsocketEventId_epubReady);
_bookVersion = newVersion;
ReportProgress(LocalizationManager.GetString("PublishTab.Epub.PreparingPreview", "Preparing Preview"));
// This three-tries loop is an attempt to recover from a weird state the system sometimes gets into
// where a browser won't navigate to a temporary page that the EpubMaker uses. I'm not sure it actually
// helps, once the system gets into this state even a brand new browser seems to have the same problem.
// Usually there will be no exception, and the loop breaks at the end of the first iteration.
for (int i = 0; i < 3; i++)
{
try
{
if (!PublishHelper.InPublishTab)
{
return(false);
}
_previewSrc = UpdateEpubControlContent();
}
catch (ApplicationException ex)
{
if (i >= 2)
{
throw;
}
ReportProgress("Something went wrong, trying again");
continue;
}
break; // normal case, no exception
}
lock (_epubMakerLock)
{
if (EpubMaker.AbortRequested)
{
return(false); // the code that set the abort flag will request a new preview.
}
}
}
finally
{
lock (_epubMakerLock)
{
_stagingEpub = false;
}
}
// Do pending save if the user requested it while the preview was still in progress.
SaveAsEpub();
ReportProgress(LocalizationManager.GetString("PublishTab.Epub.Done", "Done"));
return(true);
}
