GraphQL Schema

Generating GraphQL schema definitions using Schema Definition Language (SDL).

Quick Start

# Basic type definition
type_def = """
type User {
  id: ID!
  name: String!
  email: String
}
"""

# Write to file
with open('schema.graphql', 'w') as f:
    f.write(type_def)

Type Definitions

# Scalar types: String, Int, Float, Boolean, ID

# Object type
"type User { id: ID! username: String! posts: [Post!]! }"

# Input type (for mutations)
"input CreateUserInput { username: String! email: String! }"

# Enum type
"enum UserRole { ADMIN USER GUEST }"

Queries and Mutations

# Queries (read operations)
query_type = """
type Query {
  user(id: ID!): User
  users: [User!]!
}
"""

# Mutations (write operations)
mutation_type = """
type Mutation {
  createUser(input: CreateUserInput!): User!
  updateUser(id: ID!, input: UpdateUserInput!): User!
  deleteUser(id: ID!): Boolean!
}
"""

Field Modifiers

# Type!          - Required (non-null)
# Type           - Optional (nullable)
# [Type]         - Array (can be null)
# [Type]!        - Required array (can be empty)
# [Type!]!       - Required array of required items

# Examples
"""
type Example {
  required: String!
  optional: String
  list: [String]
  requiredList: [String]!
  strictList: [String!]!
}
"""

Schema Generation

def generate_schema(types, queries, mutations):
    """Generate complete GraphQL schema"""
    parts = list(types)

    if queries:
        parts.append(f"type Query {{\n  " + '\n  '.join(queries) + "\n}")

    if mutations:
        parts.append(f"type Mutation {{\n  " + '\n  '.join(mutations) + "\n}")

    return '\n\n'.join(parts)

Resolver Stubs

# Python resolver template
def create_resolver_stub(field_name, args, return_type):
    args_str = ', '.join(args.keys()) if args else ''
    return f"""
def resolve_{field_name}(parent, info{', ' + args_str if args_str else ''}):
    # TODO: Implement {field_name} resolver
    # Returns: {return_type}
    pass
"""