Struct HttpCsvWriter 

pub struct HttpCsvWriter { /* private fields */ }

HTTP CSV writer that generates CSV files in memory for streaming responses

This writer generates the entire CSV file in memory and can be used to stream responses in web servers. Supports optional compression.

Example

use excelstream::HttpCsvWriter;

let mut writer = HttpCsvWriter::new();
writer.write_row(&["ID", "Name", "Value"])?;
writer.write_row(&["1", "Alice", "100"])?;
writer.write_row(&["2", "Bob", "200"])?;

let csv_bytes = writer.finish()?;
// Send csv_bytes as HTTP response body

Implementations

impl HttpCsvWriter

pub fn new() -> Self

Create a new HTTP CSV writer (uncompressed)

Example

use excelstream::HttpCsvWriter;

let mut writer = HttpCsvWriter::new();
writer.write_row(&["Name", "Age"])?;
writer.write_row(&["Alice", "30"])?;

let bytes = writer.finish()?;

pub fn with_compression(compression_level: u32) -> Self

Create a new HTTP CSV writer with Deflate/Gzip compression

Arguments

• compression_level - Compression level from 0 to 9:
  • 0: No compression (fastest)
  • 1: Fast compression
  • 6: Balanced (recommended)
  • 9: Maximum compression (slowest)

Note: HTTP streaming only supports Deflate compression. For Zstd compression, use file-based CsvWriter instead.

Example

use excelstream::HttpCsvWriter;

let mut writer = HttpCsvWriter::with_compression(6);
writer.write_row(&["Name", "Age"])?;
writer.write_row(&["Alice", "30"])?;

let compressed_bytes = writer.finish()?;

pub fn delimiter(self, delim: u8) -> Self

Set custom delimiter (builder pattern)

pub fn quote_char(self, quote: u8) -> Self

Set custom quote character (builder pattern)

pub fn write_row<I, S>(&mut self, data: I) -> Result<()>

where I: IntoIterator<Item = S>, S: AsRef<str>,

Write a row of strings

Example

use excelstream::HttpCsvWriter;

let mut writer = HttpCsvWriter::new();
writer.write_row(&["Name", "Age", "City"])?;
writer.write_row(&["Alice", "30", "NYC"])?;

pub fn write_row_typed(&mut self, cells: &[CellValue]) -> Result<()>

Write a row of typed values

Example

use excelstream::{HttpCsvWriter, CellValue};

let mut writer = HttpCsvWriter::new();
writer.write_row_typed(&[
    CellValue::String("Alice".to_string()),
    CellValue::Int(30),
    CellValue::Float(75.5),
])?;

pub fn row_count(&self) -> u64

Get the number of rows written

pub fn finish(self) -> Result<Vec<u8>>

Finish writing and return the CSV bytes

This consumes the writer and returns the complete CSV file as bytes.

Example

use excelstream::HttpCsvWriter;

let mut writer = HttpCsvWriter::new();
writer.write_row(&["Name", "Age"])?;
writer.write_row(&["Alice", "30"])?;

let csv_bytes = writer.finish()?;
// Now send csv_bytes as HTTP response

Trait Implementations

impl Default for HttpCsvWriter

fn default() -> Self

Returns the “default value” for a type.