[Parquet] Add ParquetMetadataPushDecoder

parquet/src/errors.rs

@@ -52,6 +52,9 @@ pub enum ParquetError {
     /// Returned when a function needs more data to complete properly. The `usize` field indicates
     /// the total number of bytes required, not the number of additional bytes.
     NeedMoreData(usize),
+    /// Returned when a function needs more data to complete properly.
+    /// The `Range<u64>` indicates the range of bytes that are needed.
+    NeedMoreDataRange(std::ops::Range<u64>),
 }
 
 impl std::fmt::Display for ParquetError {
@@ -69,6 +72,9 @@ impl std::fmt::Display for ParquetError {
             }
             ParquetError::External(e) => write!(fmt, "External: {e}"),
             ParquetError::NeedMoreData(needed) => write!(fmt, "NeedMoreData: {needed}"),
+            ParquetError::NeedMoreDataRange(range) => {
+                write!(fmt, "NeedMoreDataRange: {}..{}", range.start, range.end)
+            }
         }
     }
 }

parquet/src/file/metadata/mod.rs

@@ -40,11 +40,10 @@
 //! metadata into parquet files. To work with metadata directly,
 //! the following APIs are available:
 //!
-//! * [`ParquetMetaDataReader`] for reading
+//! * [`ParquetMetaDataReader`] for reading from a reader for I/O
+//! * [`ParquetMetaDataPushDecoder`] for decoding from bytes without I/O
 //! * [`ParquetMetaDataWriter`] for writing.
 //!
-//! [`ParquetMetaDataReader`]: https://docs.rs/parquet/latest/parquet/file/metadata/struct.ParquetMetaDataReader.html
-//! [`ParquetMetaDataWriter`]: https://docs.rs/parquet/latest/parquet/file/metadata/struct.ParquetMetaDataWriter.html
 //!
 //! # Examples
 //!
@@ -92,6 +91,7 @@
 //!                         * Same name, different struct
 //! ```
 mod memory;
+mod push_decoder;
 pub(crate) mod reader;
 mod writer;
 
@@ -120,6 +120,7 @@ use crate::schema::types::{
 };
 #[cfg(feature = "encryption")]
 use crate::thrift::{TCompactSliceInputProtocol, TSerializable};
+pub use push_decoder::ParquetMetaDataPushDecoder;
 pub use reader::{FooterTail, PageIndexPolicy, ParquetMetaDataReader};
 use std::ops::Range;
 use std::sync::Arc;