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Fetching more than 1000 rows from Domino LDAP server using .NET Core 5 and Novell.Directory.Ldap.NETStandard

I want to fetch all the users from a large location of our Domino LDAP, around ~2000 users altogether. Since .NET Core sadly doesn't have a platform independent LDAP library, I'm using Novell.Directory.Ldap.NETStandard with this POC:
var cn = new Novell.Directory.Ldap.LdapConnection();
cn.Connect("dc.internal", 389);
cn.Bind("user", "pw");
string filter = "location=MyLoc";
var result = cn.Search("", Novell.Directory.Ldap.LdapConnection.ScopeOne, filter, new string[] { Novell.Directory.Ldap.LdapConnection.AllUserAttrs }, typesOnly: false);
int count = 0;
while (result.HasMore()) {
var entry = result.Next();
count++;
Console.WriteLine(entry.Dn);
}
It prints me a lot of entries, but not all. When count = 1000 I got an Size Limit Exceeded exception. I guess this is because I need to use some kind of pagination, so not all entries woult be returned in a single request. There are different questions like this or this one. Both in Java, the .NET Core API seems somehow different.
Approach 1: Try to find out how LdapSearchRequest works in .NET Core
byte[] resumeCookie = null;
LdapMessageQueue queue = null;
var searchReq = new LdapSearchRequest("", LdapConnection.ScopeOne, filter, new string[] { LdapConnection.AllUserAttrs },
LdapSearchConstraints.DerefNever, maxResults: 3000, serverTimeLimit: 0, typesOnly: false, new LdapControl[] { new SimplePagedResultsControl(size: 100, resumeCookie) });
var searchRequest = cn.SendRequest(searchReq, queue);
I'm trying to figure out how the Java examples can be used in .NET Core. This looks good, however I can't figure out how to fetch the LDAP entries. I only get an message id. By looking into the source it seems that I'm on the right way, but they're using MessageAgent which cannot be used outside since it's internal sealed. This is propably the reason why searching for LdapRearchRequest in the source code doesn't give many results.
Approach 2: Using SimplePagedResultsControlHandler
var opts = new SearchOptions("", LdapConnection.ScopeOne, filter, new string[] { LdapConnection.AllUserAttrs });
// For testing purpose: https://github.com/dsbenghe/Novell.Directory.Ldap.NETStandard/issues/163
cn.SearchConstraints.ReferralFollowing = false;
var pageControlHandler = new SimplePagedResultsControlHandler(cn);
var rows = pageControlHandler.SearchWithSimplePaging(opts, pageSize: 100);
This throws a Unavaliable Cricital Extension exception. First I thought that this is an issue of the .NET port, which may doesn't support all the features of the original Java library yet. It seems complete and according to further researches, it looks like to be an LDAP error code. So this must be something which has to be supported by the server, but is not supported by Domino.

I couldn't make at least one of those approachs work, but found another way: Cross platform support for the System.DirectoryServices.Protocols namespace was was added in .NET 5. This was missing for a long time in .NET Core and I guess this is the main reason why libraries like Novell.Directory.Ldap.NETStandard were ported to .NET Core - in times of .NET Core 1.x this was the only way I found to authenticate against LDAP wich works on Linux too.
After having a deeper look into System.DirectoryServices.Protocols, it works well out of the box, even for ~2k users. My basic POC class looks like this:
public class DominoLdapManager {
LdapConnection cn = null;
public DominoLdapManager(string ldapHost, int ldapPort, string ldapBindUser, string ldapBindPassword) {
var server = new LdapDirectoryIdentifier(ldapHost, ldapPort);
var credentials = new NetworkCredential(ldapBindUser, ldapBindPassword);
cn = new LdapConnection(server);
cn.AuthType = AuthType.Basic;
cn.Bind(credentials);
}
public IEnumerable<DominoUser> Search(string filter, string searchBase = "") {
string[] attributes = { "cn", "mail", "companyname", "location" };
var req = new SearchRequest(searchBase, filter, SearchScope.Subtree, attributes);
var resp = (SearchResponse)cn.SendRequest(req);
foreach (SearchResultEntry entry in resp.Entries) {
var user = new DominoUser() {
Name = GetStringAttribute(entry, "cn"),
Mail = GetStringAttribute(entry, "mail"),
Company = GetStringAttribute(entry, "companyname"),
Location = GetStringAttribute(entry, "location")
};
yield return user;
}
yield break;
}
string GetStringAttribute(SearchResultEntry entry, string key) {
if (!entry.Attributes.Contains(key)) {
return string.Empty;
}
string[] rawVal = (string[])entry.Attributes[key].GetValues(typeof(string));
return rawVal[0];
}
}
Example usage:
var ldapManager = new DominoLdapManager("ldap.host", 389, "binduser", "pw");
var users = ldapManager.Search("objectClass=person");
But it's not solved with Novell.Directory.Ldap.NETStandard as the title said
This doesn't solve my problem with the Novell.Directory.Ldap.NETStandard library as the title suggested, yes. But since System.DirectoryServices.Protocols is a official .NET package maintained by Microsoft and the .NET foundation, this seems the better aproach for me. The foundation will take care to keep it maintained and compatible with further .NET releases. When I wrote the question, I was not aware of the fact that Linux support is added now.
Don't get me wrong, I don't want to say that third packages are bad by design - that would be completely wrong. However, when I have the choice between a official package and a third party one, I think it makes sense to prefer the official one. Except there would be a good reason against that - which is not the case here: The official package (which doesn't exist in the past) works better to solve this issue than the third party one.

How to configure an oracle database in apache ignite .NET

I'm trying to configure the write-through and read-through properties of apache Ignite with an Oracle database. I searched in many places like the Ignite oficial documentation, also in the ignite examples on GitHub,
but there isn't much information or examples coded in C# that is the lenguaje in which I'm developing my app.
What I want is to retrieve from a persistent store (in this case an Oracle database), an specific data in the cache (Ignite) that is not already loaded. In a similar way, I need all my changes on the cache to be reflected on the database.
I tied to create and spring.xml with the configuration of the database (ip, port, username, pass, database), but I can't make it work if that is the way it should be done.
Thanks in advance and sorry for my english.

1) Implement ICacheStore interface (or inherit CacheStoreAdapter helper class)
public class OracleStore : CacheStoreAdapter
{
public override object Load(object key)
{
using (var con = new OracleConnection
{
ConnectionString = "User Id=<username>;Password=<password>;Data Source=<datasource>"
})
{
con.Open();
var cmd = con.CreateCommand();
cmd.CommandText = "SELECT * FROM MyTable WHERE ID=#id";
cmd.Parameters.Add("#id", OracleType.Int32);
cmd.Parameters["#id"].Value = key;
using (var reader = cmd.ExecuteReader())
{
// Read data, return as object
}
}
}
public override void Write(object key, object val)
{
oracleDb.UpdateRow(key, val);
}
public override void Delete(object key)
{
oracleDb.DeleteRow(key);
}
}
2) Implement store factory:
public class OracleStoreFactory : IFactory<OracleStore>
{
public OracleStore CreateInstance()
{
return new OracleStore();
}
}
3) Configure cache to use store:
using (var ignite = Ignition.Start())
{
var cacheCfg = new CacheConfiguration
{
ReadThrough = true,
WriteThrough = true,
KeepBinaryInStore = false, // Depends on your case
CacheStoreFactory = new OracleStoreFactory()
};
var cache = ignite.CreateCache<int, MyClass>(cacheCfg);
cache.Get(1); // OracleStore.Load is called.
}
Documentation for Ignite.NET (in C#): https://apacheignite-net.readme.io/docs/persistent-store
C# examples are available in a full download package: https://ignite.apache.org/download.cgi#binaries (click apache-ignite-fabric-1.9.0-bin.zip, download, unzip, open platforms\dotnet\examples\Apache.Ignite.Examples.sln)
Blog post explaining cache store implementation in C#:
https://ptupitsyn.github.io/Entity-Framework-Cache-Store/
Working with Oracle DB in .NET: Connecting to Oracle Database through C#?

Application settings Windows phone 8

I'm developing for WP8 and I need to store custom app settings. I found func 'ApplicationData' but it's not supported in WP8. Can you help me? I want to store permanent variables provided by user. For example:
Country = UA
News = 1
etc.

You can use Isolated Storage or ApplicationData.LocalSettings like this :
var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
// Create a simple setting
localSettings.Values["exampleSetting"] = "Hello Windows";
// Read data from a simple setting
Object value = localSettings.Values["exampleSetting"];
if (value == null)
{
// No data
}
else
{
// Access data in value
}
// Delete a simple setting
localSettings.Values.Remove("exampleSetting");
Check this Link and also this Link

How to store data in Isolated Storage in Windows Phone 7

I am building an app for windows phone 7.
I am using data which is coming from the web service which i want to save in isolated storage so that next time when the data is viewed it shows the data even when offline.
My cs file is:
public about()
{
InitializeComponent();
KejriwalService.aapSoapClient myclient = new KejriwalService.aapSoapClient();
myclient.getarvindAboutCompleted += new EventHandler<KejriwalService.getarvindAboutCompletedEventArgs>(myclient_getarvindAboutCompleted);
myclient.getarvindAboutAsync();
}
void myclient_getarvindAboutCompleted(object sender, KejriwalService.getarvindAboutCompletedEventArgs e)
{
var data = e.Result;
XElement xml = XElement.Parse(data);
aboutview.Text = xml.Elements("UserDetails").Elements("about_details").First().Value;
}

One of the easiest way to store data is to store them in the IsolatedStorageSettings. You can make a property for this purpose:
string PropertyName
{
get
{
var settings = System.IO.IsolatedStorage.IsolatedStorageSettings.ApplicationSettings;
if (settings.Contains("valueKeyName"))
return (string)settings["valueKeyName"];
else
return null;
}
set
{
var settings = System.IO.IsolatedStorage.IsolatedStorageSettings.ApplicationSettings;
if (settings.Contains("valueKeyName"))
settings["valueKeyName"] = value;
else
settings.Add("valueKeyName", value);
}
}
IsolatedStorageSettings store pairs key-value in the dictionary. You should just choose key name of your storing value and name of the property.

with the help ofIsolatedStorageSettings you could save your data in the form of key value paire like this:
var Iso_settings = System.IO.IsolatedStorage.IsolatedStorageSettings.ApplicationSettings;
if (!Iso_settings.Contains("yourDataKey"))
{
Iso_settings.Add("yourDataKey", yourDataValue);
Iso_settings.Save()//This will save your data in isolated storage.
}

Don't go for Sqlite if you don't want offline data and to store Data two best method is to use Isolated Storage and using linq so if you have only 1-2 data members and you have to change there values then you can use Isolated Storage otherwise go for linq if you have 2-3 columns and rows to store data in form of Tables.
Isolated storage is used like this:
try
{
if (IsolatedStorageSettings.ApplicationSettings.Contains("email_id"))
{
IsolatedStorageSettings.ApplicationSettings["email_id"] = emailid;
IsolatedStorageSettings.ApplicationSettings["password"] = password;
IsolatedStorageSettings.ApplicationSettings.Save();
}
else
{
IsolatedStorageSettings.ApplicationSettings.Add("email_id", emailid);
IsolatedStorageSettings.ApplicationSettings.Add("password", password);
IsolatedStorageSettings.ApplicationSettings.Save();
}
}
catch (Exception ex)
{
Console.WriteLine(ex.InnerException);
}
For linq http://www.codeproject.com/Articles/43025/A-LINQ-Tutorial-Mapping-Tables-to-Objects go for the link.

Best practice to create (on demand) SQL Server 2008 Express databases in C#?

The purpose is to handle the user's data (you can call them project, document, file, or whatever) in a brand new SQL Server 2008 Express database. The data are expected to occupy much less space than the 4GB available with the express edition (which is also free to distribute).
E.g., each time the user selects File->New command, a new empty database will be created at the specified location. On the other hand, a similar command, File->Open must provide support to retrieve the list of the databases to select one for opening.
So, the following issues must be resolved:
a) The application must be able to create the connection string and attach the database to SQL Server 2008 Express through code (C#)
b) The application must be able to retrieve (again through code) a list with all the available databases, to give the user a chance to select one to open.
I think it would be helpful to have a template database in resources and copy it in the location specified by the user.
Do you think it is a working solution? Do you have any suggestions?

There's lots you can do with Sql Server Management Objects (SMO):
// Add a reference to Microsoft.SqlServer.Smo
// Add a reference to Microsoft.SqlServer.ConnectionInfo
// Add a reference to Microsoft.SqlServer.SqlEnum
using Microsoft.SqlServer.Management.Smo;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Data;
public class SqlServerController
{
private Server m_server = null;
public SqlServerController(string server)
{
m_server = new Server(server);
}
public void AttachDatabase(string database, StringCollection files,
AttachOptions options)
{
m_server.AttachDatabase(database, files, options);
}
public void AddBackupDevice(string name)
{
BackupDevice device = new BackupDevice(m_server, name);
m_server.BackupDevices.Add(device);
}
public string GetServerVersion(string serverName)
{
return m_server.PingSqlServerVersion(serverName).ToString();
}
public int CountActiveConnections(string database)
{
return m_server.GetActiveDBConnectionCount(database);
}
public void DeleteDatabase(string database)
{
m_server.KillDatabase(database);
}
public void DetachDatabase(string database, bool updateStatistics,
bool removeFullTextIndex)
{
m_server.DetachDatabase(database, updateStatistics, removeFullTextIndex);
}
public void CreateDatabase(string database)
{
Database db = new Database(m_server, database);
db.Create();
}
public void CreateTable(string database, string table,
List<Column> columnList, List<Index> indexList)
{
Database db = m_server.Databases[database];
Table newTable = new Table(db, table);
foreach (Column column in columnList)
newTable.Columns.Add(column);
if (indexList != null)
{
foreach (Index index in indexList)
newTable.Indexes.Add(index);
}
newTable.Create();
}
public Column CreateColumn(string name, DataType type, string #default,
bool isIdentity, bool nullable)
{
Column column = new Column();
column.DataType = type;
column.Default = #default;
column.Identity = isIdentity;
column.Nullable = nullable;
return column;
}
public Index CreateIndex(string name, bool isClustered, IndexKeyType type,
string[] columnNameList)
{
Index index = new Index();
index.Name = name;
index.IndexKeyType = type;
index.IsClustered = isClustered;
foreach (string columnName in columnNameList)
index.IndexedColumns.Add(new IndexedColumn(index, columnName));
return index;
}
}

An alternate solution is to use SQLite rather than SQL Express. You can even continue to use ADO.NET if you use this solution. SQLite databases are simply files, and your connection strings can refer to the file path. When a user wants to open their file, they can select an actual file.

I get the impression that this database will live locally on user's machine. If that's the case, sql server express is not usually a good database choice. It's a server-class engine rather than a desktop or in process engine. Instead, there are a number of good in process engines you can use: Sql Server Compact Edition, Sqlite (as mentioned by Jacob) or even Access.

If you believe SQL Server Express 2008 is the right choice (sqllite does seem to fit better though), I would look at using User Instances which will allow non-administrators to add databases from files as you describe.

This article shows how to create a new database, and attach it to a SQL Server database instance:
How to: Attach a Database File to SQL Server Express
http://msdn.microsoft.com/en-us/library/ms165673.aspx
These article shows how to manage the attaching and detaching of existing databases:
http://msdn.microsoft.com/en-us/library/ms190794.aspx
http://www.databasejournal.com/features/mssql/article.php/2224361/Attaching-and-Detaching-Databases-on-SQL-Server.htm

For the following connection string for SQL Server 2008 R2.
<connectionstring>Data Source=.\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=True;Pooling=True</connectionstring>
you can do
var connectionString = new SqlConnectionStringBuilder(connectionString);
var serverConnection = new ServerConnection("DatabaseInstanceName in server");
var serverInstance = new Server(serverConnection);
if (serverInstance.Databases.Contains(connectionString.InitialCatalog))
serverInstance.KillDatabase(connectionString.InitialCatalog);
var db = new Database(serverInstance, connectionString.InitialCatalog);
try
{
db.Create();
}
catch (SqlException ex)
{
throw;
}
Thanks to Mr. Harvey for pointing the right direction. Although in my case, I have to make these small changes. Because, I use the windows authentication.