IS4Code/WarcProtocol

Parser for WARC (aka WebArchive) files

Toimik.WarcProtocol

.NET 5 C# WARC parser.

Features

• Parses uncompressed / compressed - as a whole or per record - Web ARChive (WARC) version 1.0 / 1.1 files
• Option to terminate or resume processing upon encountering malformed content
• Creates WARC records with auto-generated WARC-Block-Digest / WARC-Payload-Digest using configurable hash algorithm

Quick Start

Installation

Package Manager

PM> Install-Package Toimik.WarcProtocol

.NET CLI

> dotnet add package Toimik.WarcProtocol

Usage

using System.Diagnostics;
using System.Threading.Tasks;

class Program
{
    static async Task Main(string[] args)
    {
        var parser = new WarcParser();

        // Path to a WARC file that contains one or more records, which may be uncompressed or
        // compressed (as a whole or per record)
        var path = "uncompressed.warc";

        // Use a '.gz' file extension to indicate that the file is compressed using GZip
        // var path "compressed.warc.gz";

        // In case any part of the WARC file is malformed and parsing is expected to resume -
        // rather than throwing an exception and terminates - a parse log is specified
        var parseLog = new DebugParseLog();

        // Parse the file and process the records accordingly
        var records = parser.Parse(path, parseLog);

        // Alternatively, use a stream:
        // var stream = ...
        // var isCompressed = ... // true if the stream is compressed; false otherwise
        // var records = parser.Parse(stream, isCompressed, parseLog);

        await foreach (WarcProtocol.Record record in records)
        {
            switch (record.Type)
            {
                case ContinuationRecord.TypeName:

                    // ...
                    break;

                case ConversionRecord.TypeName:

                    // ...
                    break;

                case MetadataRecord.TypeName:

                    // ...
                    break;

                case RequestRecord.TypeName:

                    // ...
                    break;

                case ResourceRecord.TypeName:

                    // ...
                    break;

                case ResponseRecord.TypeName:

                    // ...
                    break;

                case RevisitRecord.TypeName:

                    // ...
                    break;

                case WarcinfoRecord.TypeName:

                    // ...
                    break;

                case "custom-type":

                    // ...
                    break;
            }
        }
    }

    class DebugParseLog : IParseLog
    {
        public void ChunkSkipped(string chunk)
        {
            Debug.WriteLine(chunk);
        }

        public void ErrorEncountered(string error)
        {
            Debug.WriteLine(error);
        }
    }
}