🛠️ [TASK] : Add Basic Database Queries to support the signed_docs table.

[stevenj]

PR: #1322 adds a Postgresql table to serve as a signed document's repository.
Create supporting queries for that table in the catalyst-gateway/bin/src/db/event/signed_docs path.
Follow the structure for query implementation as shown in the catalyst-gateway/bin/src/db/event/config path.

The query operations that will be required initially are:

• Add SQL query templates #1371
• Implement catalyst-gateway/event-db/queries/insert_signed_documents.sql query make a function for cat-gateway service #1375
  • IF the record primary key (id,ver) does not exist, then add the new record. Return success.
  • IF the record does exist, but all values are the same as stored, return Success.
  • Otherwise return an error. (Can not over-write an existing record with new data).
• Implement catalyst-gateway/event-db/queries/select_signed_documents.sql.jinja query make a function for cat-gateway service #1376
  • This returns a single document. All data from the document is returned, including the payload and raw fields.
  • ver should be able to be optional, in which case get the latest ver of the given id
• Implement catalyst-gateway/event-db/queries/select_signed_documents_2.sql.jinja query make a function for cat-gateway service #1377
  • id
  • id and ver
  • type
  • author
  • type and author
  • There will be other query options, this function should take an enum type as a parameter, which contains the required variables. The Enum type then can emit the necessary WHERE clause to append to the query, Results should always be sorted by id and then ver.
  • Al Limit parameter is required, which can optionally define the Maximum number of records returned, and the Offset of the records tor return. See: https://www.postgresql.org/docs/current/queries-limit.html
  • Sort results by type, id, ver

None of these endpoints is to take any raw SQL, it is to construct it from defined and controlled parameters.
For example, it is impermissible to pass a "WHERE" query string to any of these functions.

Each of these queries is to be an independent PR of this ticket.

As these functions require a PostgreSQL database to function, and data injected within it, they do not need unit tests. They will be tested via integration tests which are outside the scope of this ticket. However, any sub-functions which do not have a dependency on external IO should have appropriate unit tests.