feat: expose unique columns and many-to-many markers in OpenAPI

Add unique constraint and many-to-many relationship metadata to the
generated OpenAPI spec so clients can render them.

- Store unique constraints on Table as tableUniqueCols (mirroring
  tablePKCols) instead of denormalizing them onto each Column.
- Compute unique constraints via a per-table tbl_unique_cols CTE in
  tablesSqlQuery.
- Annotate unique columns and composite unique constraints in property
  descriptions, and emit m2m markers in table descriptions.

test/io/__snapshots__/test_cli/test_schema_cache_snapshot[dbTables].yaml

@@ -8,6 +8,7 @@
     tableName: authors_only
     tablePKCols: []
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: cats
@@ -39,6 +40,7 @@
     tablePKCols:
     - id
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: items_w_isolation_level
@@ -69,6 +71,7 @@
     tableName: items_w_isolation_level
     tablePKCols: []
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: directors
@@ -100,6 +103,7 @@
     tablePKCols:
     - id
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: projects
@@ -112,6 +116,7 @@
     tableName: projects
     tablePKCols: []
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: infinite_recursion
@@ -124,6 +129,7 @@
     tableName: infinite_recursion
     tablePKCols: []
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: false
 
 - - qiName: awards
@@ -182,6 +188,7 @@
     tablePKCols:
     - id
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: films
@@ -222,6 +229,7 @@
     tablePKCols:
     - id
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true
 
 - - qiName: items
@@ -243,4 +251,5 @@
     tableName: items
     tablePKCols: []
     tableSchema: public
+    tableUniqueCols: []
     tableUpdatable: true

test/io/test_connection.py

@@ -239,7 +239,7 @@ def test_pool_acquisition_timeout(level, defaultenv, metapostgrest):
         assert data["message"] == "Timed out acquiring connection from connection pool."
 
         # ensure the message appears on the logs as well
-        output = sorted(postgrest.read_stdout(nlines=10))
+        output = sorted(drain_stdout(postgrest))
 
         if level == "crit":
             assert len(output) == 0

test/io/test_log.py

@@ -44,7 +44,7 @@ def test_log_level(level, defaultenv):
         response = postgrest.session.get("/")
         assert response.status_code == 200
 
-        output = postgrest.read_stdout(nlines=9)
+        output = drain_stdout(postgrest)
 
         if level == "crit":
             assert len(output) == 0
@@ -82,7 +82,7 @@ def test_log_level(level, defaultenv):
                     r'- - postgrest_test_anonymous \[.+\] "GET / HTTP/1.1" 200 \d+ "" "python-requests/.+"',
                 ],
             )
-            assert len(output) == 9
+            assert len(output) > 3
             assert any("Connection" and "is available" in line for line in output)
             assert any("Connection" and "is used" in line for line in output)
 
@@ -403,7 +403,7 @@ def test_db_error_logging_to_stderr(level, defaultenv, metapostgrest):
         assert response.status_code == 500
 
         # ensure the message appears on the logs
-        output = postgrest.read_stdout(nlines=8)
+        output = drain_stdout(postgrest)
 
         if level == "crit":
             assert len(output) == 0