parquet/src/schema/mod.rs

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//
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//! Parquet schema definitions and methods to print and parse schema.
//!
//! # Example
//!
//! ```rust
//! use parquet::{
//!     basic::{ConvertedType, Repetition, Type as PhysicalType},
//!     schema::{parser, printer, types::Type},
//! };
//! use std::sync::Arc;
//!
//! // Create the following schema:
//! //
//! // message schema {
//! //   OPTIONAL BYTE_ARRAY a (UTF8);
//! //   REQUIRED INT32 b;
//! // }
//!
//! let field_a = Type::primitive_type_builder("a", PhysicalType::BYTE_ARRAY)
//!     .with_converted_type(ConvertedType::UTF8)
//!     .with_repetition(Repetition::OPTIONAL)
//!     .build()
//!     .unwrap();
//!
//! let field_b = Type::primitive_type_builder("b", PhysicalType::INT32)
//!     .with_repetition(Repetition::REQUIRED)
//!     .build()
//!     .unwrap();
//!
//! let schema = Type::group_type_builder("schema")
//!     .with_fields(&mut vec![Arc::new(field_a), Arc::new(field_b)])
//!     .build()
//!     .unwrap();
//!
//! let mut buf = Vec::new();
//!
//! // Print schema into buffer
//! printer::print_schema(&mut buf, &schema);
//!
//! // Parse schema from the string
//! let string_schema = String::from_utf8(buf).unwrap();
//! let parsed_schema = parser::parse_message_type(&string_schema).unwrap();
//!
//! assert_eq!(schema, parsed_schema);
//! ```

pub mod parser;
pub mod printer;
pub mod types;
pub mod visitor;