Working with Parsed Data

Examples using the Schema class from the openapi_to_code module.

openapi_to_code.py ↗

schema = Schema("openapi.json")

List tables

auth.auth_user

for table in schema:
    prefix = f"{table.namespace}." if table.namespace else ""
    print(f"{prefix}{table.table}")
# blog.blog_post

Foreign keys

post = schema["BlogPost"]
for name, col in post.fk_columns.items():
    print(f"{name} -> {col.ref} ({col.fk})")
# author_id -> auth.user (auth.user.id)

Relationships

# author: has_many -> blog_post
# role: many_to_many via auth_role_auth_user
user = schema["AuthUser"]
for rel in user.relationships.values():
    if rel.type == "many_to_many":
        print(f"{rel.name}: M2M via {rel.through['table']}")
    else:
        print(f"{rel.name}: {rel.type} -> {rel.target_table}")

Constraints

user = schema["AuthUser"]

user.unique_columns          # ["email", "username"]

# Write-only (hidden from reads)
[c.name for c in user.columns.values() if c.write_only]  # ["password"]

# Defaults
{c.name: c.default for c in user.columns.values() if c.default is not None}
# {"is_active": True, "created_at": {"expr": "NOW()"}}

Computed columns

for name, col in table.computed_columns.items():
    print(f"{name}: storage={col.storage}, expr={col.computed}")
# full_name: storage=stored, expr={'fn': 'concat', 'args': [{'col': 'first_name'}, ' ', {'col': 'last_name'}]}
# age: storage=virtual, expr={'fn': 'years_since', 'args': [{'col': 'birth_date'}]}

Generate DDL

A minimal example showing how parsed data feeds code generation:

def generate_create_table(table: Table, dialect: str = "postgres") -> str:
    lines = []
    for col in table.columns.values():
        if col.is_app_only:
            continue
        sql_type = col.sql_type.get(dialect, "TEXT")
        parts = [f"  {col.name} {sql_type}"]
        if not col.nullable and col.name not in table.pk:
            parts.append("NOT NULL")
        lines.append(" ".join(parts))

    pk = ", ".join(table.pk)
    lines.append(f"  PRIMARY KEY ({pk})")
    body = ",\n".join(lines)
    return f"CREATE TABLE {table.table} (\n{body}\n);"

CREATE TABLE auth_role (
  created_at TIMESTAMPTZ NOT NULL,
  id UUID,
  name VARCHAR(100) NOT NULL,
  updated_at TIMESTAMPTZ NOT NULL,
  PRIMARY KEY (id)
);