Merge pull request #40 from GSA-TTS/document-revision-support

Update frontmatter to pull revision details

OSCAL_REFERENCE.md

@@ -19,7 +19,11 @@ For docker-trestle, the `control-implementation` section is maintained and edite
 | `title` | Title of the SSPP document |
 | `last-modified` | Do not edit - automatically generated timestamp |
 | `version` | Version of the SSP document. Revise whenever submitting final doc for approvals |
-| `oscal-version` | Version of OSCAL in use. trestle currently supports `1.0.4` |
+| `oscal-version` | Version of OSCAL in use. trestle currently supports `1.1.2` |
+| `revisions` | Version history of the document. Used to populate `Document Revision History` table in the templates |
+| `roles` | Names of roles referenced within `responsible-parties` lists |
+| `parties` | People and organizations involved with the creation of the System and SSPP |
+| `responsible-parties` | Mappings of parties to roles |
 
 ### System Characteristics
 

templates/ssp-rendering/lato/templates/frontmatter.md

@@ -39,8 +39,12 @@ Document Prepared By
 
 Document Revision History
 
+{% set prepared_by = ssp_interface.first_array_entry(ssp_interface.get_parties_for_role(ssp.metadata.responsible_parties, "prepared-by")) %}
 | Date | Comments | Version | Author |
 | ---- | -------- | ------- | ------ |
-| | | | |
+{% for revision in ssp_interface.safe_retrieval(ssp.metadata, 'revisions', []) %}
+{% set revision_prepared_by = ssp_interface.get_party_by_uuid(control_interface.get_prop(revision, 'prepared-by')) or prepared_by %}
+| {{ revision.last_modified.strftime('%Y-%m-%d') if revision.last_modified else '' }} | {{ revision.title }} | {{ revision.version }} | {{ revision_prepared_by.name }} |
+{% endfor %}
 
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