ZCML File
configure.zcml

<configure
    xmlns="http://namespaces.zope.org/zope"
    xmlns:browser="http://namespaces.zope.org/browser"
    i18n_domain="zope"
    >
<utility
    component=".vocabulary.SourceTypeVocabulary"
    provides="zope.schema.interfaces.IVocabularyFactory"
    name="SourceTypes"
    />
<utility
    component=".plaintext.PlainTextSourceFactory"
    name="zope.source.plaintext"
    />
<browser:view
    class=".plaintext.PlainTextToHTMLRenderer"
    permission="zope.Public"
    for=".plaintext.IPlainTextSource"
    name=""
    />
<utility
    component=".stx.StructuredTextSourceFactory"
    name="zope.source.stx"
    />
<browser:view
    class=".stx.StructuredTextToHTMLRenderer"
    permission="zope.Public"
    for=".stx.IStructuredTextSource"
    name=""
    />
<utility
    component=".rest.ReStructuredTextSourceFactory"
    name="zope.source.rest"
    />
<browser:view
    class=".rest.ReStructuredTextToHTMLRenderer"
    permission="zope.Public"
    for=".rest.IReStructuredTextSource"
    name=""
    />
</configure>