TextFileEventSink.cs

using System;
using System.IO;
using Waher.Runtime.IO;
 
namespace Waher.Events.Files
{
    public class TextFileEventSink : TextWriterEventSink
    {
        private StreamWriter file;
        private readonly FileNameTimeSequence fileSequence;
        private readonly int deleteAfterDays;
 
        public TextFileEventSink(string ObjectID, string FileName)
            : this(ObjectID, FileName, 7)
        {
        }
 
        public TextFileEventSink(string ObjectID, string FileName, int DeleteAfterDays)
            : base(ObjectID, null)
        {
            this.file = null;
            this.output = null;
            this.fileSequence = new FileNameTimeSequence(FileName, true);
            this.deleteAfterDays = DeleteAfterDays;
 
            string FolderName = Path.GetDirectoryName(FileName);
 
            if (!Directory.Exists(FolderName))
            {
                Log.Informational("Creating folder.", FolderName);
                Directory.CreateDirectory(FolderName);
            }
        }
 
        protected override void BeforeWrite()
        {
            if (!this.fileSequence.TryGetNewFileName(out string s))
                return;
 
            try
            {
                this.file?.Dispose();
            }
            catch (Exception)
            {
                // Ignore
            }
 
            this.file = null;
            this.output = null;
 
            this.output = this.file = File.CreateText(s);
 
            if (this.deleteAfterDays < int.MaxValue)
            {
                string FolderName = Path.GetDirectoryName(s);
 
                Runtime.IO.Files.DeleteOldFiles(FolderName, TimeSpan.FromDays(this.deleteAfterDays), SearchOption.AllDirectories, true);
            }
        }
 
        public override void DisposeOutput()
        {
            base.DisposeOutput();
 
            this.file?.Dispose();
            this.file = null;
        }
    }
}