From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan Nieder Subject: Re: [GSoC] Git to SVN bridge Date: Thu, 19 Apr 2012 17:56:59 -0500 Message-ID: <20120419225659.GA4971@burratino> References: <20120418201050.GB30625@burratino> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Git List To: Ramkumar Ramachandra X-From: git-owner@vger.kernel.org Fri Apr 20 00:57:19 2012 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1SL0Hu-0000eu-VM for gcvg-git-2@plane.gmane.org; Fri, 20 Apr 2012 00:57:19 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756826Ab2DSW5N (ORCPT ); Thu, 19 Apr 2012 18:57:13 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:41426 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754710Ab2DSW5M (ORCPT ); Thu, 19 Apr 2012 18:57:12 -0400 Received: by iagz16 with SMTP id z16so12522394iag.19 for ; Thu, 19 Apr 2012 15:57:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=58B92dTcRhb8Uoa5rVnRe+twT/TrHS6yCBcHHWaWm3k=; b=he7NsIzyJ6knsw2IFVQIvOl7hfswz8mk5mt2e05NEKp/Ni4mGPRnnRKwCxtzxl8Yv1 NLHkkqm5J2pgjrRgo7+2A8OR7PuSmVGdvxTY813LgY+Y26ApMPoaYZhi04/RMRk2FiCg NHa3RetWd04QB+ZOnhx7qKr9R4+7UvcWnCK1IDq4IBaVDhwfWC3Gpzva36sRlJTJPs76 OMjuWNYPb7xe6BU473HRQqcERo1DXWECdTw8CPVqHqh7aVnXkoSxXVQRrdHukxf4mOAA JnWB0k8DD9I1St1Tj11KlixpVKf+goJVw6m3VLiS/hSx+cQ1UNqBIe/c5kjNoKolQt/M SkYA== Received: by 10.50.216.232 with SMTP id ot8mr8553265igc.22.1334876232144; Thu, 19 Apr 2012 15:57:12 -0700 (PDT) Received: from burratino ([64.134.171.237]) by mx.google.com with ESMTPS id i6sm1130125igq.3.2012.04.19.15.57.07 (version=SSLv3 cipher=OTHER); Thu, 19 Apr 2012 15:57:10 -0700 (PDT) Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Ramkumar Ramachandra wrote: > Give 'vcs-svn/' the ability to spit out a Subversion dumpfile. If you > remember, we hit a brick wall last time when we needed a way to > persist mark-referenced-blobs in the fast-import stream. Yeah. Ok, let's start there. If I remember correctly, before we had this idea that svn-fi would be a generic fast-import backend, so we could get support for pushing to Subversion from other version control systems like Mercurial and RCS for free. An earlier idea was to use a very minimal subset of the fast-import format. You started with a patch that taught fast-export a switch to produce that minimal subset, which was rejected because it seemed like too much of a niche use case to be worth the cost to compatibility. However, that leaves whole swaths of the design space unexplored. For example, maybe "git fast-export" doesn't need to write the restricted format but there would be a filter that takes an arbitrary fast-import stream and converts it to the restricted thing. Or maybe it would be easiest to get something off the ground using that restricted "fast-import lite" format and only afterwards expand svn-fi to handle more commands so it can talk to the rest of the world. In other words, if you are hitting a wall with that part which doesn't seem to have much to do with differences between git and Subversion anyway, I imagine there are easier places to start. Alternatively, if you prefer to work on making it easy for an importer to handle "ls" and "cat" commands and mark references, I think our previous attempts were misguided and we can do better. :) What do you think? Jonathan