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Indexes: Indexing Attachments

The AttachmentsFor method returns a list of attachments in a given document as well as basic information like Name or Size about each of them.

IEnumerable<AttachmentName> AttachmentsFor(object doc);
public string Name;

public string Hash;

public string ContentType;

public long Size;

Creating an index using AttachmentsFor()

The AttachmentsFor method is available in AbstractIndexCreationTask.

public class Employees_ByAttachmentNames : AbstractIndexCreationTask<Employee>
{
    public class Result
    {
        public string[] AttachmentNames { get; set; }
    }

    public Employees_ByAttachmentNames()
    {
        Map = employees => from e in employees
                           let attachments = AttachmentsFor(e)
                           select new Result
                           {
                               AttachmentNames = attachments.Select(x => x.Name).ToArray()
                           };
    }
}

Querying the index

//return all employees that have an attachment called "cv.pdf"
List<Employee> employees = session
    .Query<Employees_ByAttachmentNames.Result, Employees_ByAttachmentNames>()
    .Where(x => x.AttachmentNames.Contains("cv.pdf"))
    .OfType<Employee>()
    .ToList();
//return all employees that have an attachment called "cv.pdf"
List<Employee> employees = await asyncSession
    .Query<Employees_ByAttachmentNames.Result, Employees_ByAttachmentNames>()
    .Where(x => x.AttachmentNames.Contains("cv.pdf"))
    .OfType<Employee>()
    .ToListAsync();
//return all employees that have an attachment called "cv.pdf"
List<Employee> employees = session
    .Advanced
    .DocumentQuery<Employee, Employees_ByAttachmentNames>()
    .ContainsAny("AttachmentNames", new[] { "cv.pdf" })
    .ToList();