In the metadata-only spec a TODO reside with the following action:
publish schema at https://www.softwareheritage.org/schema/2018/deposit
which is followed with this example:
```
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom"
xmlns:codemeta="https://doi.org/10.5063/SCHEMA/CODEMETA-2.0"
xmlns:swh="https://www.softwareheritage.org/schema/2018/deposit">
<author>
<name>HAL</name>
<email>hal@ccsd.cnrs.fr</email>
</author>
<client>hal</client>
<external_identifier>hal-01243573</external_identifier>
<codemeta:name>The assignment problem</codemeta:name>
<codemeta:url>https://hal.archives-ouvertes.fr/hal-01243573</codemeta:url>
<codemeta:identifier>other identifier, DOI, ARK</codemeta:identifier>
<codemeta:applicationCategory>Domain</codemeta:applicationCategory>
<codemeta:description>description</codemeta:description>
<codemeta:author>
<codemeta:name> author1 </codemeta:name>
<codemeta:affiliation> Inria </codemeta:affiliation>
<codemeta:affiliation> UPMC </codemeta:affiliation>
</codemeta:author>
<codemeta:author>
<codemeta:name> author2 </codemeta:name>
<codemeta:affiliation> Inria </codemeta:affiliation>
<codemeta:affiliation> UPMC </codemeta:affiliation>
</codemeta:author>
<swh:deposit>
<swh:reference>
<swh:origin url='https://github.com/user/repo'/>
</swh:reference>
</swh:deposit>
</entry>
```
We should choose a better url for the schema.
I think there is a draft for that somewhere, but not sure where.