Datamodel distribution with biblatex

Question

I am now making new tools to use biblatex in my studies area, i. e. classical philology.

Some of theses tools need new datatypes or new fields. For example, I am making two tools:

• one to manage manuscript description with biblatex: need new datatype (@manuscript) and new fields (support, dating, scribe, shelfmark etc.) (see https://github.com/maieul/biblatex-manuscripts-philology)
• one to add a new field, which is the true author of a text. I am explaining: the author field will contain the name of the author as edited, but the "realauthor" field will contain the name of the author whom scholars think is the real author of the work (problem of pseudonym and false attribution, very often in my specialty)

These two tools are independent. I hope these two tools are enough generic to be distributed as contribution. But here is my problem. If I read well the biblatex handbook, in the section "4.5.3 Data Model Specification", I don't see how I could distribute my two contribution independently AND allow people to use them in the same project.

• I can't distribute them as styles: only one style can be precised when loading biblatex.
• I can't distribute them as datamodel: only one datamodel can be precised when loading biblatex.
• biblatex-dm.cfg and biblatex.cfg have to be created by the user
• there is no possibility to define a datamodel in a .sty file.

Answer 1

This is a bit hackish, but may be an inspiration for a proper solution.

Biblatex loads datamodels very early, before processing any options defined in biblatex style files (.bbx or .cbx). This is why you can't control datamodel loading from within a style. You need to do adjustments before the biblatex is called. Below I describe how this can be done with a package. I assume that your tools are additions to some base biblatex style which your users can freely choose. Suppose your style and package are called dmtools and you want two options manu (to load a manuscript datamodel defined in dmtools-manu.dbx) and fields (to load additional fields defined in dmtools-fields.dbx). You also have dmtools.bbx and dmtools.cbx with some macro definitions.

This is how these style and package are used:

\documentclass{article}
\usepackage[
  basestyle=apa,
  manu,
  fields,
]{dmtools}

\usepackage[style=dmtools, ...]{biblatex}
\addbibresource{...}

\begin{document}
...
\end{document} 

basestyle is the base biblatex style to which your tools will serve as additions. If you don't need it, that is if your tools are supposed to provide additions to one bib style only, you can move the biblatex call inside the .sty file.

Your package files then look like this:

dmtools.sty

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{dmtools}

\RequirePackage{kvoptions}

% options declarations
%
\DeclareBoolOption{manu}
\DeclareBoolOption{fields}
\DeclareStringOption[numeric]{basestyle}

\ProcessKeyvalOptions*

\ifdmtools@manu
  \def\dmtmanu{dmtools-manu}    % the name of .dbx file for the 'manu' tool
\fi

\ifdmtools@fields
  \def\dmtfields{dmtools-fields}    % the name of .dbx file for the 'fields' tool
\fi

\ifx\dmtools@basestyle\@empty
\else
  \def\dmtbasestyle{\dmtools@basestyle} % the name of bibstyle to load later
\fi

\endinput

This declares options and sets some commands and \if's to be used later. The basestyle option is optional and if absent the numeric style is used.

dmtools.dbx

% DM Tools data models

% load datamodel for the 'manu' tool
\ifdmtools@manu
  \blx@inputonce{\dmtmanu.dbx}{DM Tools data model}{}{}{}{}
\fi

% load datamodel for the 'fields' tool
\ifdmtools@fields
  \blx@inputonce{\dmtfields.dbx}{DM Tools data model}{}{}{}{}
\fi

% load datamodel for the style specified in the 'basestyle' option
\ifx\dmtools@basestyle\@empty
\else
  \blx@inputonce{\dmtbasestyle.dbx}{biblatex style data model}{}{}{}{}
\fi

\endinput

This file loads your datamodels and also the datamodel for the basestyle. You will probably need to adjust this to handle also bibstyle and citestyle options.

Finally, bibliography and citation style files:

dmtools.bbx

\ProvidesFile{dmtools.bbx}

\RequireBibliographyStyle{\dmtbasestyle}

\ifdmtools@manu
  %
  %  macro (re)definitions
  % 
\fi

\ifdmtools@fields
  %
  %  macro (re)definitions
  % 
\fi

\endinput

dmtools.cbx

\ProvidesFile{dmtools.cbx}

\RequireCitationStyle{\dmtbasestyle}

\ifdmtools@manu
  %
  %  mscro (re)definitions
  % 
\fi

\ifdmtools@fields
  %
  %  mscro (re)definitions
  % 
\fi

\endinput

These files load the basestyle bib- and cite-styles and then (re)define macros/commands that you need for your tools.