public object GetValue(string name)
{
Log.Debug($"GetValue called on path {Path}");
if (Path == null || !Path.Contains("."))
{
// If at the top, or at a server, the next part can't be a tag:
string nextPath = (Path == null) ? name : $"{Path}.{name}";
return(new OPCDataProvider {
Path = nextPath, Snapshot = this.Snapshot
});
}
string[] pathSplit = Path.Split(new char[] { '.' }, 2); // {Server Name}.{remaining.tag.path}
Folder folder = opcServerOrm.Fetch().Select(ext => ext.GetEntity()).FirstOrDefault(f => f.EntityName == pathSplit[0]) as Folder;
if (folder == null)
{
throw new Exception($"Could not find server named {pathSplit[0]}");
}
string[] eventIds = FolderService.GetFolderEntities <OPCEvent>(folder.FolderID).Select(e => e.Id).ToArray();
BaseTagValue mostRecentTag = null;
IDictionary <string, BaseTagValue> sourceDict = ((Snapshot as IDictionary <string, BaseTagValue>) ?? OPCEngine.mostRecentValues);
foreach (string eventId in eventIds)
{
string key = $"{eventId}|{pathSplit[1]}.{name}";
BaseTagValue tag;
if (sourceDict.TryGetValue(key, out tag))
{
if (mostRecentTag == null || mostRecentTag.TimeStamp < tag.TimeStamp)
{
mostRecentTag = tag;
}
}
}
if (mostRecentTag != null)
{
return(TagValueUtils.GetObjectValueFromTag(mostRecentTag));
}
// No current value found, so check folders to see whether this is a folder or a tag:
Folder tagDataFolder = folder.GetSubFolder().FirstOrDefault(x => x.EntityName == "Tag Data");
if (tagDataFolder == null)
{
throw new Exception("Tag data folder not found");
}
string[] parts = pathSplit[1].Split('.');
Folder currentFolder = tagDataFolder;
for (int i = 0; i < parts.Length; ++i)
{ // descend for each part, arriving at the folder which should contain the named entity
Folder nextFolder = currentFolder.GetSubFolder().FirstOrDefault(x => x.EntityName == parts[i]);
if (nextFolder == null)
{
throw new Exception($"Folder '{parts[i]}' not found in folder '{currentFolder?.EntityName}'.");
}
currentFolder = nextFolder;
}
Folder namedFolder = FolderService.GetFolderEntities <Folder>(currentFolder.FolderID).FirstOrDefault(x => x.EntityName == name);
if (namedFolder != null)
{
return new OPCDataProvider {
Path = $"{this.Path}.{name}", Snapshot = this.Snapshot
}
}
;
OPCTag namedTag = FolderService.GetFolderEntities <OPCTag>(currentFolder.FolderID).FirstOrDefault(x => x.EntityName == name);
if (namedTag != null)
{
throw new Exception($"Tag '{name}' has no known value");
}
else
{
throw new Exception($"No tag or folder '{name}' found in '{currentFolder.EntityName}'");
}
}
private static void UpdateTagsInFolder(string folderId, string baseFolderId, string serverUrl, OpcNode[] opcNodes)
{
// get the set of tags + folders within this folder, so that missing ones can be removed:
HashSet <string> oldTagNames = new HashSet <string>(FolderService.GetFolderEntities <OPCTag>(folderId).Select(x => x.EntityName));
HashSet <string> oldFolderNames = new HashSet <string>(FolderService.GetFolderEntities <Folder>(folderId).Select(x => x.EntityName));
foreach (OpcNode node in opcNodes)
{
if (ArrayUtilities.IsEmpty(node.Children))
{ // create or update tag
oldTagNames.Remove(node.Name);
OPCTag tag = FolderService.GetFolderEntities <OPCTag>(folderId).FirstOrDefault(x => x.EntityName == node.Name)
?? new OPCTag();
tag.EntityName = node.Name;
tag.EntityFolderID = folderId;
tag.Path = node.FullPath;
tag.TypeName = node.TypeName;
tag.ServerUrl = serverUrl;
tag.Store();
}
else
{
oldFolderNames.Remove(node.Name);
Folder sf = FolderService.GetFolderEntities <Folder>(folderId).FirstOrDefault(x => x.EntityName == node.Name);
if (sf == null)
{
new Folder
{
EntityName = node.Name,
EntityFolderID = folderId,
FolderBehaviorType = typeof(DefaultFolderBehavior).FullName
}.Store();
// create, then fetch to make sure id is present.
sf = FolderService.GetFolderEntities <Folder>(folderId).FirstOrDefault(x => x.EntityName == node.Name);
if (sf == null)
{
throw new Exception($"Folder {node.Name} could not be created in {folderId}.");
}
}
UpdateTagsInFolder(sf.FolderID, baseFolderId, serverUrl, node.Children);
}
}
foreach (string removedTag in oldTagNames)
{
OPCTag tag = FolderService.GetFolderEntities <OPCTag>(folderId).FirstOrDefault(x => x.EntityName == removedTag);
if (tag != null)
{ // delete tag & matching flow constant:
tag.Delete();
string flowConstantId = $"OPCTAG__{baseFolderId}__{tag.Path}";
new ORM <FlowConstant>().Delete(flowConstantId);
}
}
foreach (string removedFolder in oldFolderNames)
{
Folder folder = FolderService.GetFolderEntities <Folder>(folderId).FirstOrDefault(x => x.EntityName == removedFolder);
if (folder != null)
{
folder.Delete();
}
}
}