Merging two AspNet Profiles–more complex then one would think!

During recent code revision, a developer accidentally removed in Web.Config, the applicationName on the SQLProfileProvider element. The consequence became apparent when support started to report customers saved-reports-definitions(which was stored here) had disappeared.

   <add name="ErrorProfileProvider" connectionStringName="LocalSQLServer" type="System.Web.Profile.SqlProfileProvider" />
The problem was identified, but there was a second problem…  We had a significant number of new customers that also saved reports-definitions to this error profile provider. A simple switch back by adding the applicationName would mean that these reports-definitions would disappear (which customer support did not want to see happen to new customers – a rather bad experience).
My initial take was “Oh, I have used multiple membership providers in one web application in the past, so we just need to use the same pattern…” 
  • Oops that pattern did not work, Grrr.
  • Searching stackoverflow and other sites, did not find any “canned solutions”.
  • We looked at trying to merge the data in SQL Server, it could be done – but the TSQL code was complicated and would require major setup in QA to test properly. Not a good scenario for an agile solution.
What I ended up doing was my original pattern but I had to go to lower level coding to do it (i.e. using inherited classes features). 
First, I indeed put multiple profiles in web.config as was my original plan:
<profile inherits="AdminConsole.CustomProfile" defaultProvider="GoodProfileProvider" enabled="true">
<clear />        
<add name=GoodProfileProvider" applicationName="/Admin Console" connectionStringName="LocalSQLServer" type="System.Web.Profile.SqlProfileProvider" />        
<add name="ErrorProfileProvider" applicationName="/" connectionStringName="LocalSQLServer" type="System.Web.Profile.SqlProfileProvider" />      
The next step was to write a method (ProfileMerge) that would be called when users logged in. I added it as a static in my profile class. The code is below, the basic steps were:
  1. Check if the customer has two profiles, if not and only the correct one – then we are done
    1. Otherwise just move one into the other “in bulk”
  2. Next we need to check when the last update happened, the old one was off line, so
    1. Older then error one – we need to update
    2. Newer – we have already updated (No need to create a “updated” field to track this)
  3. We used inherited classes to call GetPropertyValues so we can process the information as collections.
  4. We walked the ErrorData (the recently created saved-reports-definitions) to find any recent definitions that we needed to merge into the old profile data. When we found one, we called a merging routine (specific to how the reports were being saved)
  5. Once all of this was done, we set the results into the good profile and returned. The profile was already being saved in the calling code, so there was not a need to do an explicit save.
   public class CustomProfile : ProfileBase
        public static void ProfileMerge(string userName, bool isForced)
                if (String.IsNullOrWhiteSpace(userName))
                int total = 0;
                var profile = CustomProfile.Create(userName);
                if (profile==null || profile.IsAnonymous) return;
                var errorPM = (SqlProfileProvider)System.Web.Profile.ProfileManager.Providers["ErrorProfileProvider"];
                if (errorPM == null) return;
                var errorDate = DateTime.MaxValue;
                foreach (ProfileInfo item in errorPM.FindProfilesByUserName(ProfileAuthenticationOption.Authenticated, userName, 0, 1, out total))
                    errorDate = item.LastUpdatedDate;
                var goodPM = (SqlProfileProvider)System.Web.Profile.ProfileManager.Providers["GoodProfileProvider"];
                if (goodPM == null)
                    //Should never occur
                    AdminConsole.Diagnostics.SplunkLogger.Fatal("Profile not found for " + userName);
                // If date is in the future, there is no data to merge
                if (errorDate > DateTime.Now)
                // Already done the update BUT allow manual repeat if needed.
                if (profile.LastUpdatedDate > errorDate && ! isForced) return;
                var errorData = errorPM.GetPropertyValues(profile.Context, CustomProfile.Properties);
                var goodData = goodPM.GetPropertyValues(profile.Context, CustomProfile.Properties);
                foreach (SettingsPropertyValue item in errorData)
                    if(item.PropertyValue !=null && ! String.IsNullOrWhiteSpace( item.PropertyValue.ToString()))
                    switch (item.Name)
                        case "UserSavedFilters_Consumer":
                        case "UserSavedFilters_TransactionUsage":
                        case "UserSavedFilters":
                            goodData[item.Name].PropertyValue= MergeStrings(item.Name,goodData[item.Name].PropertyValue.ToString(),item.PropertyValue.ToString());
                goodPM.SetPropertyValues(profile.Context, goodData);
            catch (Exception ex)
        private static string MergeStrings(string name,string oldData, string newData)
            var logEntry = new Dictionary<string, string>();
            logEntry.Add("AP_name", name);
            logEntry.Add("AP_old", oldData);
            logEntry.Add("AP_current", newData);
            char[] spliter = { '$' };
            if (String.IsNullOrWhiteSpace(oldData)) return newData;
            if (String.IsNullOrWhiteSpace(newData)) return oldData;
            var oldCollection = oldData.Split(spliter, StringSplitOptions.RemoveEmptyEntries);
            var newCollection = newData.Split(spliter, StringSplitOptions.RemoveEmptyEntries);
            var merge = new HashSet<String>();
            foreach (string item in oldCollection)
                if (!merge.Contains(item))
            foreach (string item in newCollection)
                if (!merge.Contains(item))
            var result = new StringBuilder();
            foreach (string item in merge)
            logEntry.Add("AP_result", result.ToString());
            return result.ToString();
You may have noted that I included an ability to ignore dates and force a merge.  This was done to provide a backdoor mechanism for support if the unexpected happen. They could enter the userid on a dark page (only visible to them), and force the update to happened again (which would log the results of the merge so we could find why our code (and QA) had failed).
The good news is that the above has rolled into production and our QA person reports that customer service is happy because everything was returned as expected. We did not need to use our dark page.


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