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New Post: anr (ambiguous name resolution) query or other special queries

dotjoe — Fri, 21 Dec 2012 15:13:36 GMT

Are anr queries supported? What about the matching rule OIDs for bitwise comparisons? For example, I can include only Active users with this (!(userAccountControl:1.2.840.113556.1.4.803:=2)) or only security groups with (groupType:1.2.840.113556.1.4.803:=2147483648) (more examples). Are there other ways to perform these kind of filters?

New Post: how to use linq "Take()" statement

madhatter22 — Sat, 25 Feb 2012 14:21:51 GMT

Take isn't supported, but it's pretty easy to add it yourself. All of these changes are made to the DirectorySource class. Just create a nullable class variable that gets set in the Parse method for Take. I've highlighted the changes below:

public void Parse(Expression ex)
{
	var ce = ex as ConstantExpression;
	var mce = ex as MethodCallExpression;

	if (ce != null)
	{
		_source = ce.Value as IDirectorySource;
                originalType = _source.OriginalType;
        }
        else if (mce != null)
        {
                //
                // Should be extension methods on Queryable.
                //
                if (mce.Method.DeclaringType != typeof(Queryable))
                    throw new NotSupportedException("Detected invalid top-level method-call.");

                Parse(mce.Arguments[0]);

                //
                // First parameter to the method call represents the (unary) lambda in LINQ style.
                // E.g. (user => user.Name == "Bart") for a Where  clause
                //      (user => new { user.Name })   for a Select clause
                //
                switch (mce.Method.Name)
                {
                    //
                    // Builds the query LDAP expression.
                    //
                    case "Where":
                        BuildPredicate(((UnaryExpression)mce.Arguments[1]).Operand as LambdaExpression);
                        break;
                    //
                    // Builds the projection and filters the required properties.
                    //
                    case "Select":
                        BuildProjection(((UnaryExpression)mce.Arguments[1]).Operand as LambdaExpression);
                        break;

	            case "Take":

			_takeValue = (int)((ConstantantExpression)mce.Arguments[1]).Value;
		        break;
                    default:
                        throw new NotSupportedException("Unsupported query operator: " + mce.Method.Name);
                }
        }
	else
                throw new NotSupportedException("Invalid expression node detected.");
}

Once that's done you just need to check it and set it when you perform a search:

private IEnumerator<T> GetResults()
{
    DirectorySchemaAttribute[] attr = (DirectorySchemaAttribute[])originalType.GetCustomAttributes(typeof(DirectorySchemaAttribute), false);
    if (attr == null || attr.Length == 0)
        throw new InvalidOperationException("Missing schema mapping attribute.");

    string classQuery = String.Format("(objectClass={0})", attr[0].Schema);

    DirectorySearcher s = Helpers.CloneSearcher(
        _source.Searcher,
        !string.IsNullOrEmpty(query) ? String.Format("(&{0}{1})", classQuery, query) : classQuery,
        properties.ToArray()
    );
    if (_takeValue.HasValue) s.SizeLimit = _takeValue.Value;

    //rest of method to perform search...
}

As for paging the results, LDAP doesn't really support paging the way LINQ expects it to work. Paging is kind of abstracted away and only exposed through a cookie returned from the server. You can read more about it here: http://tools.ietf.org/html/rfc2696.

You can tell the DirectorySearcher to get everything by setting a sufficiently large PageSize, but getting a subset and then going to get more is not possible from what I can tell.

You can filter by group. Just map the memberOf property as a string[] and do something like this:

context.Where(u => u.memberOf.Contains("[distinguished name of group]"))

This will find all users that are a member of that group.

New Post: Get user list but ...

anAgent — Fri, 17 Feb 2012 00:18:36 GMT

Yes. You just need to model your you DirectoryEntity for your ADUser like so:

[DirectorySchema("user", typeof(IADsUser))]
public class ADUser : DirectoryEntity
{
	[DirectoryAttribute("givenName")]
	public string FirstName { get; set; }
	
	[DirectoryAttribute("Mail")]
	public string EmailAddress { get; set; }
	
	[DirectoryAttribute("sn")]
	public string LastName { get; set; }
	
}

New Post: Get groups from OU

anAgent — Fri, 17 Feb 2012 00:16:44 GMT

I think this is basically what' you're looking for.

1) Create the Group class modeling from the example provided in this framework:

2) Create a basic Context class;

    sealed class MyContext : DirectoryContext
    {
        public MyContext(DirectoryEntry searchRoot)
            : base(searchRoot)
        {
        }
        [DirectorySearchOptions(SearchScope.Subtree)]
        public DirectorySource<ADGroup> Groups { get; set; }
    }

3) Query you data. Just sent the OU path to where you want to query.

	
MyContext ctx = new MyContext(new DirectoryEntry("LDAP://OU=Users,OU=TEST,DC=mydc,DC=com")); 

var groups = from x in ctx.Groups
		 where x.Name.StartsWith("Test")
		 select x;

foreach (var g in groups)
{
Console.WriteLine(g.Name);
}

New Post: how to use linq "Take()" statement

touhami — Tue, 14 Feb 2012 13:20:25 GMT

Hello

linq take statement is not supported in this project

any one have idea how to query first 20 (grid pagesize) from linq to ad queury?

and when page index change load next 20 results?

other limitation i cant filter by group (memberOf)

Any one has an idea how to filter by group?

tahnk you very much for your help

New Post: Get user list but ...

Kris_I — Tue, 13 Sep 2011 12:08:12 GMT

Hello,

Is there a way to get all users from AD but with email, firstname, lastname ?

Thanks,

New Post: Get groups from OU

Kris_I — Tue, 13 Sep 2011 11:22:24 GMT

Hello,

Is there a way to get all the Groups (not the users) available in the Organization Unit (OU) "Security Groups" ?

Thanks,

New Post: The project is alive ?

madhatter22 — Fri, 26 Aug 2011 03:29:48 GMT

jkinter,

Here's the extension method I use to clean filter values:

public static string CleanFilterValue(this string value)
{
    var sb = new StringBuilder();
    foreach (var curChar in value)
    {
        switch (curChar)
        {
            case '\\':
                sb.Append("\\5c");
                break;
            case '*':
                sb.Append("\\2a");
                break;
            case '(':
                sb.Append("\\28");
                break;
            case ')':
                sb.Append("\\29");
                break;
            case '\u0000':
                sb.Append("\\00");
                break;
            default:
                sb.Append(curChar);
                break;
        }
    }
    return sb.ToString();
}

You could call this on the value and pass in the result so you won't have to change your apps. It's been a while since I've looked at the LINQ to AD source so I'm not sure where you could add this in there. I hope this helps.

New Post: The project is alive ?

jkinter — Thu, 18 Aug 2011 21:29:22 GMT

bdesmet wrote:

In fact a brand new version of LINQ to AD will appear fairly soon. I've been busy doing quite an extensive rewrite of the query translator as part of my day-to-day job. Check out http://blogs.bartdesmet.net/bart for some hints as to what I'm up to nowadays. While I can't give a firm timeframe just yet, I'd encourage you to keep an eye on the website.

Cheers,
-Bart

Hi Bart,

We're using this project in several of our internal solutions and I've recently come up against the "special characters" issue and was wondering how soon is "fairly soon"? This post was quite some time ago and I'd really rather not have to assume the technical debt of pulling out your solution and replacing it with the LinqToLDAP solution. Please advise.

Thanks.

New Post: Mapping to System.DirectoryServices instead of ActiveDs

tgreaves — Fri, 01 Jul 2011 14:43:07 GMT

The description says that it supports both but how do you map to one instead of the other? The reason I ask is because my project that is going to use this is compiled for "Any cpu" and when running on x64, I get the usual COM exception.. Compiling under x86 makes it work correctly but I dont want to do that..

New Post: DateTime issues with 4.0 Framework

azeltroth — Wed, 29 Jun 2011 22:25:44 GMT

Just wondering if anyone has tried to upgrade this project and use it with the 4.0 framework?

I am using this project to wrap my AD, and calling it using a WCF service. It works beautifully in the 4.0 framework, except it seems to have issues bringing back values that are DateTime data types. All other data types seem to work without issues.

My code is simple:

    Dim ROOT As New System.DirectoryServices.DirectoryEntry("LDAP://xxxxx", "xxxxx", "xxxxx")
    Dim users As New DirectorySource(Of ADLinq.User)(ROOT, SearchScope.Subtree)
    Dim res = From usr In users Where usr.Name.StartsWith(searchcriteria)
    Dim dt As DataTable = HelperFunctions.GetBlankTable(GetType(ADLinq.User))
    Dim dr As DataRow
    For Each u In res
       dr = dt.NewRow()
       HelperFunctions.AddRow(dr, u)
       dt.Rows.Add(dr)
    Next
    Dim ds As New DataSet()
    ds.Tables.Add(dt)
    Return ds

The issue occurs in the class DirectorySource.cs, in the function AssignResultProperty. For a data type of DateTime (In my case PasswordLastChanged) when it attempts to get the PropertyInfo from the helper object, the variable 'p' is null, and it crashes on a nullreferenceexception.

The line it crashes on is line 496 of DirectorySource.cs. p is null so there for it crashes.

All other datatypes, it works perfectly, except for DateTime.

Interestingly enough, when I create an Identical service using the 3.5 framework, these issues do not seem to occur. Which tends to lean me towards one of the two references that have changed being the culprit. System.DirectoryServices, or System.Data, however I am not sure.

Was just wondering if anyone has also discovered this issue, or am I totally alone on this one? And if you have figured it out, how did you do so?

Thanks in Advance,

Jason Schatz

New Post: The project is alive ?

madhatter22 — Sat, 14 May 2011 16:44:02 GMT

Jetski5822,

You're welcome to use http://linqtoldap.codeplex.com/. However, I use System.DirectoryServices.Protocols to get broader LDAP server support so if you're use to just System.DirectoryServices there's a slight learning curve (if you want to dig into the internals). If LINQ to AD gets updated I'll delete this post, but right now like this project looks dead.

New Post: The project is alive ?

Jetski5822 — Thu, 24 Feb 2011 21:24:18 GMT

Im going to implement it in http://orchardopenauth.codeplex.com/ Could you tell us when your going to release a new version?

New Post: The project is alive ?

MadHatter22 — Mon, 10 Jan 2011 05:32:27 GMT

Any news, Bart?

New Post: The project is alive ?

jerrynixon — Mon, 08 Nov 2010 21:47:40 GMT

Which calendar year is "quite soon" in?

New Post: Finding the last logon date time

PerrySharePoint — Thu, 04 Nov 2010 04:21:33 GMT

With the obvious caveat that this only gets you the last logon date against whichever domain controller your query was executed.

Ref, e.g., http://blogs.dirteam.com/blogs/jorge/archive/2008/02/10/showing-last-logon-info-at-logon-in-windows-server-2008.aspx

New Post: Getting user attributes dynamically

wrecklesswun — Sat, 30 Oct 2010 14:59:25 GMT

I see that the user entity is built using a predefined set of attributes to return. Is there a way to dynamically get attributes at runtime based on selected attributes?

Thanks

New Post: VS2010

CreepyGnome — Sat, 30 Oct 2010 01:55:05 GMT

Hi Bart,

Do you know when the VS2010/.Net 4 targeted version of Linq to AD will be released?

Kind Regards

New Post: How to get a list of contacts?

jorgevazquez — Thu, 14 Oct 2010 01:13:39 GMT

I am a total newbie to programming, Visual Basic, Visual Studio, and LINQ. I am trying to build a very simple web application to manage *contact* items at any given OU in Active Directory. I would like to use LINQ to Active Directory to allow me to get the list of contacts, as well as create new contacts, and updated and delete existing contacts. I have been doing a *lot* of reading for the past two weeks trying to get this to work, but I have not yet been able to accomplish what I need to do. It would be great if someone would be so kind to explain how to use LINQ to AD in Visual Studio 2010 so that I can do what I have described above step-by-step. Alternatively, if you think I should be trying something totally different, please be so kind and point me in the corrent direction.

Thank you all very much for any help you might be able to provide.

New Post: Finding the last logon date time

adeelsansari — Sat, 09 Oct 2010 05:12:46 GMT

Thanks. Very helpful.