Raise error if page is too large

src/write/page.rs

@@ -1,3 +1,4 @@
+use std::convert::TryInto;
 use std::io::Write;
 use std::sync::Arc;
 
@@ -7,12 +8,30 @@ use parquet_format_async_temp::thrift::protocol::{
 };
 use parquet_format_async_temp::{DictionaryPageHeader, Encoding, PageType};
 
-use crate::error::Result;
+use crate::error::{ParquetError, Result};
 use crate::page::{
     CompressedDataPage, CompressedDictPage, CompressedPage, DataPageHeader, ParquetPageHeader,
 };
 use crate::statistics::Statistics;
 
+fn maybe_bytes(uncompressed: usize, compressed: usize) -> Result<(i32, i32)> {
+    let uncompressed_page_size: i32 = uncompressed.try_into().map_err(|_| {
+        ParquetError::OutOfSpec(format!(
+            "A page can only contain i32::MAX uncompressed bytes. This one contains {}",
+            uncompressed
+        ))
+    })?;
+
+    let compressed_page_size: i32 = compressed.try_into().map_err(|_| {
+        ParquetError::OutOfSpec(format!(
+            "A page can only contain i32::MAX compressed bytes. This one contains {}",
+            compressed
+        ))
+    })?;
+
+    Ok((uncompressed_page_size, compressed_page_size))
+}
+
 /// Contains page write metrics.
 pub struct PageWriteSpec {
     pub header: ParquetPageHeader,
@@ -30,7 +49,7 @@ pub fn write_page<W: Write>(
     let header = match &compressed_page {
         CompressedPage::Data(compressed_page) => assemble_data_page_header(compressed_page),
         CompressedPage::Dict(compressed_page) => assemble_dict_page_header(compressed_page),
-    };
+    }?;
 
     let header_size = write_page_header(writer, &header)?;
     let mut bytes_written = header_size as u64;
@@ -68,7 +87,7 @@ pub async fn write_page_async<W: AsyncWrite + Unpin + Send>(
     let header = match &compressed_page {
         CompressedPage::Data(compressed_page) => assemble_data_page_header(compressed_page),
         CompressedPage::Dict(compressed_page) => assemble_dict_page_header(compressed_page),
-    };
+    }?;
 
     let header_size = write_page_header_async(writer, &header).await?;
     let mut bytes_written = header_size as u64;
@@ -98,47 +117,60 @@ pub async fn write_page_async<W: AsyncWrite + Unpin + Send>(
     })
 }
 
-fn assemble_data_page_header(compressed_page: &CompressedDataPage) -> ParquetPageHeader {
+fn assemble_data_page_header(page: &CompressedDataPage) -> Result<ParquetPageHeader> {
+    let (uncompressed_page_size, compressed_page_size) =
+        maybe_bytes(page.uncompressed_size(), page.compressed_size())?;
+
     let mut page_header = ParquetPageHeader {
-        type_: match compressed_page.header() {
+        type_: match page.header() {
             DataPageHeader::V1(_) => PageType::DATA_PAGE,
             DataPageHeader::V2(_) => PageType::DATA_PAGE_V2,
         },
-        uncompressed_page_size: compressed_page.uncompressed_size() as i32,
-        compressed_page_size: compressed_page.compressed_size() as i32,
+        uncompressed_page_size,
+        compressed_page_size,
         crc: None,
         data_page_header: None,
         index_page_header: None,
         dictionary_page_header: None,
         data_page_header_v2: None,
     };
 
-    match compressed_page.header() {
+    match page.header() {
         DataPageHeader::V1(header) => {
             page_header.data_page_header = Some(header.clone());
         }
         DataPageHeader::V2(header) => {
             page_header.data_page_header_v2 = Some(header.clone());
         }
     }
-    page_header
+    Ok(page_header)
 }
 
-fn assemble_dict_page_header(page: &CompressedDictPage) -> ParquetPageHeader {
-    ParquetPageHeader {
+fn assemble_dict_page_header(page: &CompressedDictPage) -> Result<ParquetPageHeader> {
+    let (uncompressed_page_size, compressed_page_size) =
+        maybe_bytes(page.uncompressed_page_size, page.buffer.len())?;
+
+    let num_values: i32 = page.num_values.try_into().map_err(|_| {
+        ParquetError::OutOfSpec(format!(
+            "A dictionary page can only contain i32::MAX items. This one contains {}",
+            page.num_values
+        ))
+    })?;
+
+    Ok(ParquetPageHeader {
         type_: PageType::DICTIONARY_PAGE,
-        uncompressed_page_size: page.uncompressed_page_size as i32,
-        compressed_page_size: page.buffer.len() as i32,
+        uncompressed_page_size,
+        compressed_page_size,
         crc: None,
         data_page_header: None,
         index_page_header: None,
         dictionary_page_header: Some(DictionaryPageHeader {
-            num_values: page.num_values as i32,
+            num_values,
             encoding: Encoding::PLAIN,
             is_sorted: None,
         }),
         data_page_header_v2: None,
-    }
+    })
 }
 
 /// writes the page header into `writer`, returning the number of bytes used in the process.
@@ -155,3 +187,28 @@ async fn write_page_header_async<W: AsyncWrite + Unpin + Send>(
     let mut protocol = TCompactOutputStreamProtocol::new(&mut writer);
     Ok(header.write_to_out_stream_protocol(&mut protocol).await? as u64)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn dict_too_large() {
+        let page = CompressedDictPage {
+            buffer: vec![],
+            uncompressed_page_size: i32::MAX as usize + 1,
+            num_values: 100,
+        };
+        assert!(assemble_dict_page_header(&page).is_err());
+    }
+
+    #[test]
+    fn dict_too_many_values() {
+        let page = CompressedDictPage {
+            buffer: vec![],
+            uncompressed_page_size: 0,
+            num_values: i32::MAX as usize + 1,
+        };
+        assert!(assemble_dict_page_header(&page).is_err());
+    }
+}