Apply lock when caching SharePoint objects |
Some SharePoint objects are not thread safe and caching can cause applications to fail and cause unexpected or unrelated user errors. To avoid this ensure locking of cached objects.
| CheckId | SPC050235 |
|---|---|
| TypeName | ApplyLockForCachingObjects |
| Severity | CriticalWarning |
| Type | Assembly |
Follow the instructions for locking the cache as described in 'Object Caching Techniques' (see link).
Bad Practice
public void CacheData()
{
SPListItemCollection oListItems = DoQueryToReturnItems();
cache.Add("ListItemCacheName", oListItems, ..);
}
{
SPListItemCollection oListItems = DoQueryToReturnItems();
cache.Add("ListItemCacheName", oListItems, ..);
}
Good Practice
private static object _lock = new object();
public void CacheData()
{
SPListItemCollection oListItems = DoQueryToReturnItems();
lock(_lock)
{
cache.Add("ListItemCacheName", oListItems, ..);
}
}
public void CacheData()
{
SPListItemCollection oListItems = DoQueryToReturnItems();
lock(_lock)
{
cache.Add("ListItemCacheName", oListItems, ..);
}
}
To suppress this violation in managed code add the following attribute to the method which contains the instruction (available since SPCAF version v5.2). Learn more about SuppressMessage here.
// Important: Ensure to have #define CODE_ANALYSIS at the beginning of your .cs file
[SuppressMessage("SPCAF.Rules.BestPracticesGroup", "SPC050235:ApplyLockForCachingObjects", Justification = "Provide reason for suppression here")]
[SuppressMessage("SPCAF.Rules.BestPracticesGroup", "SPC050235:ApplyLockForCachingObjects", Justification = "Provide reason for suppression here")]
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