EPiServer 11:通过程序转换媒体类型

Question

是否有人尝试在EPiServer中以编程方式转换媒体文件类型？

我们有一个为图像建模的类型，ImageFile，还有一个通过插件添加的类型。我们没有使用插件添加的类型，但发现上传的图像会不时被创建为错误的类型。我希望能弄清楚如何进行转换，这样我就可以运行一个预定的作业来批量转换它们，然后删除插件。

到目前为止，我可以通过编程将a复制为类型B，然后删除a。我真正想做的是将A转换为B以实现无缝过渡。

我尝试的第一件事是将图像克隆为正确的类型，但这会导致为空

var media = _contentRepository.Service.GetDescendents(SiteDefinition.Current.GlobalAssetsRoot)
.Where(i => _contentRepository.Service.Get<IContent>(i) is MediaData);
var imageFileTypeId = new ImageFile().ContentTypeID;
foreach (var img in media)
{
if (img.Get<IContent>() is GcEpiImageFile)
{
count++ // for summary
var item = _contentLoader.Service.Get<GcEpiImageFile>(img.Get<IContent>().ContentLink);
var cloneItem = item.CreateWritableClone() as ImageFile;
if (cloneItem == null) 
{
var msg = $"{item.Name}: {item.ContentLink.ID} came up null";
OnStatusChanged(msg);
summaryMessage.AppendLine(msg);
continue;
}
cloneItem.ContentTypeID = imageFileTypeId;
_contentRepository.Service.Save(cloneItem, SaveAction.Publish, AccessLevel.NoAccess);
}

我尝试的下一件事是将其克隆为基类ImageData，它似乎创建了对象，但在保存时抛出了一个未设置为对象异常实例的object引用。

var media = _contentRepository.Service.GetDescendents(SiteDefinition.Current.GlobalAssetsRoot)
.Where(i => _contentRepository.Service.Get<IContent>(i) is MediaData);
var imageFileTypeId = new ImageFile().ContentTypeID;
foreach (var img in media)
{
if (img.Get<IContent>() is GcEpiImageFile)
{
count++ // for summary
var item = _contentLoader.Service.Get<GcEpiImageFile>(img.Get<IContent>().ContentLink);
var cloneItem = item.CreateWritableClone() as ImageData;
if (cloneItem == null) 
{
var msg = $"{item.Name}: {item.ContentLink.ID} came up null";
OnStatusChanged(msg);
summaryMessage.AppendLine(msg);
continue;
}
try
{ 
cloneItem.ContentTypeID = imageFileTypeId;
}
catch (Exception ex)
{
summaryMessage.AppendLine($"exception triggered by id assignment {ex.Message}<br />{ex.InnerException}");
}
try
{ 
_contentRepository.Service.Save(cloneItem, SaveAction.Publish, AccessLevel.NoAccess);
}
catch (Exception ex)
{
summaryMessage.AppendLine(
$"exception triggered by save {ex.Message}<br />{ex.InnerException}");
}
}

这是我的堆栈跟踪：

Object reference not set to an instance of an object.
at EPiServer.Validation.Internal.RoutingSegmentValidator.Validate(IContent instance) at
EPiServer.Validation.Internal.ContextValidatorWrapper`2.Validate(Object instance, Object context) 
at EPiServer.Validation.Internal.ValidationService.ValidateRecursively(Object instance, Object context, HashSet`1 visitedInstances) 
at EPiServer.Validation.Internal.ValidationService.Validate[T](Object instance, T context) 
at EPiServer.Core.ContentProvider.Validate(IContent content, ContentSaveValidationContext saveValidationContext) 
at EPiServer.Core.Internal.DefaultContentRepository.Save(IContent content, SaveAction action, AccessLevel access) at Web.Business.ScheduledJobs.ImageConversion.Execute()

将非常感谢您的任何想法、帮助和指导

Answer 1

在EPiServer开发者论坛上向Johann Kronberg致敬，感谢他的帮助。

BEGIN TRANSACTION [ConvertTransaction]
BEGIN TRY
DECLARE @FromPropertyID1 int
DECLARE @ToPropertyID1 int
DECLARE @FromPropertyID2 int
DECLARE @ToPropertyID2 int
DECLARE @FromPropertyID3 int
DECLARE @ToPropertyID3 int
DECLARE @RC int
DECLARE @PageID int
DECLARE @FromPageType int
DECLARE @ToPageType int
DECLARE @Recursive bit
DECLARE @IsTest bit
SELECT @PageID = 1
#get your type ids from content type guid
SELECT @FromPageType = pkID FROM tblContentType WHERE ContentTypeGUID = 'guid of the media type being changed'
SELECT @ToPageType = pkID FROM tblContentType WHERE ContentTypeGUID = 'guid of the media type it is being change to'

#mapping properties THIS IS IMPORTANT!!!
SELECT @FromPropertyID1 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @FromPageType AND [Name] = 'Copyright'
SELECT @FromPropertyID2 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @FromPageType AND [Name] = 'Description'
SELECT @FromPropertyID3 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @FromPageType AND [Name] = 'Notes'
SELECT @ToPropertyID1 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @ToPageType AND [Name] = 'Copyright'
SELECT @ToPropertyID2 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @ToPageType AND [Name] = 'Alt Text'
SELECT @ToPropertyID3 = pkID FROM tblPropertyDefinition WHERE fkContentTypeID = @ToPageType AND [Name] = 'Notes'
SET @Recursive = 1
SET @IsTest = 0
print @PageID
print @FromPageType
print @ToPageType
DECLARE @MasterLanguageID int
SET @MasterLanguageID = 8
EXECUTE @RC = [dbo].[netConvertPropertyForPageType]
@PageID
,@FromPageType
,@FromPropertyID1
,@ToPropertyID1
,@Recursive
,@MasterLanguageID
,@IsTest
print @RC
EXECUTE @RC = [dbo].[netConvertPropertyForPageType]
@PageID
,@FromPageType
,@FromPropertyID2
,@ToPropertyID2
,@Recursive
,@MasterLanguageID
,@IsTest
print @RC
EXECUTE @RC = [dbo].[netConvertPropertyForPageType]
@PageID
,@FromPageType
,@FromPropertyID3
,@ToPropertyID3
,@Recursive
,@MasterLanguageID
,@IsTest
print @RC
EXECUTE @RC = [dbo].[netConvertPageType]
@PageID
,@FromPageType
,@ToPageType
,@Recursive
,@IsTest
print @RC
COMMIT TRANSACTION [ConvertTransaction]
END TRY
BEGIN CATCH
ROLLBACK TRANSACTION [ConvertTransaction]
END CATCH

-- Run separately
DECLARE @FromPageType int
SELECT @FromPageType = pkID FROM tblContentType WHERE ContentTypeGUID = '0a89e464-56d4-449f-aea8-2bf774ab8730'
EXECUTE netContentTypeDelete @ContentTypeID = @FromPageType

注意如果源类型的属性多于目标类型，则可能需要向目标添加属性。在我第一次运行时，我能够转换类型，但无法删除目标类型。