feat(cat-gateway): Add a signed documents repository storage table in the Event DB (#1322)

* refactor(cat-gateway): Move unused schemas out of the main schema directory

* feat(cat-gateway): Add signed documents repository table to the postgresql DB.

* feat(cat-gateway): Add author, and more indexes to the signed docs repository table

* fix(cat-gateway): BYTEA not BLOB

* fix(cat-gateway): move unused migrations out of the migrations folder

* fix(cat-gateway): Fix comment annotations to refer to correct table

* fix(cat-gateway): fix index names in the comments

Author: stevenj

catalyst-gateway/event-db/migrations/V2__signed_documents.sql

@@ -0,0 +1,63 @@
+-- Catalyst Voices Database - Signed Documents Repository
+-- sqlfluff:dialect:postgres
+
+-- Title : Signed Documents Repository
+
+-- Signed Documents Repository Tables
+
+-- Note: ULID are stored using the native postgresql UUID type, as they are the same size.
+-- See: https://blog.daveallie.com/ulid-primary-keys/ for a description of this approach.
+
+-- -------------------------------------------------------------------------------------------------
+
+-- Signed Documents Storage Repository defintion.
+CREATE TABLE IF NOT EXISTS signed_docs (
+  id UUID NOT NULL, -- Actually a ULID
+  ver UUID NOT NULL, -- Actually a ULID
+  type UUID NOT NULL, -- Yes its a UUID this time
+  author TEXT NOT NULL,
+  metadata JSONB NOT NULL,
+  payload JSONB NULL,
+  raw BYTEA NOT NULL,
+
+  CONSTRAINT pk PRIMARY KEY (id, ver)
+);
+
+COMMENT ON TABLE signed_docs IS
+'Storage for Signed Documents.';
+
+COMMENT ON COLUMN signed_docs.id IS
+'The Signed Documents Document ID (ULID).';
+COMMENT ON COLUMN signed_docs.ver IS
+'The Signed Documents Document Version Number (ULID).';
+COMMENT ON COLUMN signed_docs.type IS
+'The Signed Document type identifier.';
+COMMENT ON COLUMN signed_docs.author IS
+'The Primary Author of the Signed Document.';
+COMMENT ON COLUMN signed_docs.metadata IS
+'Extra metadata extracted from the Signed Document, and encoded as JSON.';
+COMMENT ON COLUMN signed_docs.payload IS
+'IF the document has a compressed json payload, the uncompressed json payload is stored here.';
+COMMENT ON COLUMN signed_docs.raw IS
+'The RAW unaltered signed document, including its signatures, and full COSE envelope.';
+
+CREATE INDEX IF NOT EXISTS idx_signed_docs_type ON signed_docs (type);
+COMMENT ON INDEX idx_signed_docs_type IS
+'Index to help finding documents by a known type faster.';
+
+CREATE INDEX IF NOT EXISTS idx_signed_docs_author ON signed_docs (author);
+COMMENT ON INDEX idx_signed_docs_author IS
+'Index to help finding documents by a known author faster.';
+
+CREATE INDEX IF NOT EXISTS idx_signed_docs_type_author ON signed_docs (type, author);
+COMMENT ON INDEX idx_signed_docs_type_author IS
+'Index to help finding documents by a known author for a specific document type faster.';
+
+
+CREATE INDEX IF NOT EXISTS idx_signed_docs_metadata ON signed_docs USING gin (metadata);
+COMMENT ON INDEX idx_signed_docs_metadata IS
+'Index to help search metadata attached to the signed documents.';
+
+CREATE INDEX IF NOT EXISTS idx_signed_docs_payload ON signed_docs USING gin (payload);
+COMMENT ON INDEX idx_signed_docs_payload IS
+'Index to help search payload data contained in a signed documents.';