Struct CsvItemReaderBuilder 

pub struct CsvItemReaderBuilder<I> { /* private fields */ }

Available on crate feature csv only.

A builder for configuring CSV item reading.

This builder allows you to customize the CSV reading behavior, including delimiter, terminator, and header handling.

Design Pattern

This struct implements the Builder pattern, which allows for fluent, chainable configuration of a CsvItemReader before creation. Each method returns self to allow method chaining.

Default Configuration

• Delimiter: comma (,)
• Terminator: CRLF (Windows-style line endings)
• Headers: disabled
• Trimming: All fields trimmed

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use spring_batch_rs::core::item::ItemReader;
use serde::Deserialize;
use csv::Terminator;

#[derive(Deserialize)]
struct Person {
    name: String,
    age: u8,
}

// Custom CSV configuration
let reader = CsvItemReaderBuilder::<Person>::new()
    .delimiter(b';')  // Use semicolon as delimiter
    .terminator(Terminator::Any(b'\n'))  // Unix line endings
    .has_headers(true)  // First row contains headers
    .from_reader("name;age\nAlice;30".as_bytes());

Implementations

impl<I> CsvItemReaderBuilder<I>

pub fn new() -> Self

Creates a new CsvItemReaderBuilder with default configuration.

Default settings:

• Delimiter: comma (,)
• Terminator: CRLF (Windows-style line endings)
• Headers: disabled

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use serde::Deserialize;

#[derive(Deserialize)]
struct Record {
    field: String,
}

let builder = CsvItemReaderBuilder::<Record>::new();

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

Sets the delimiter character for the CSV parsing.

Parameters

• delimiter: The character to use as a field delimiter

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use serde::Deserialize;

#[derive(Deserialize)]
struct Record {
    field: String,
}

// Use tab as delimiter
let builder = CsvItemReaderBuilder::<Record>::new()
    .delimiter(b'\t');

// Use semicolon as delimiter
let builder = CsvItemReaderBuilder::<Record>::new()
    .delimiter(b';');

pub fn terminator(self, terminator: Terminator) -> Self

Sets the line terminator for the CSV parsing.

Parameters

• terminator: The line terminator to use

Terminator Options

• Terminator::CRLF: Windows-style line endings (default)
• Terminator::Any(byte): Custom terminator, often b'\n' for Unix-style

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use csv::Terminator;
use serde::Deserialize;

#[derive(Deserialize)]
struct Record {
    field: String,
}

// Use Unix-style line endings (LF)
let builder = CsvItemReaderBuilder::<Record>::new()
    .terminator(Terminator::Any(b'\n'));

pub fn has_headers(self, yes: bool) -> Self

Sets whether the CSV file has headers.

When enabled, the first row is treated as headers and is not returned as part of the data. The header names can be used to match fields in the deserialization process.

Parameters

• yes: Whether headers are present

Deserialization Impact

When enabled, column names from headers can be matched to struct field names during deserialization. This is often more robust than relying on column order.

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use serde::Deserialize;

#[derive(Deserialize)]
struct Record {
    field: String,
}

// Enable headers (first row is column names)
let builder = CsvItemReaderBuilder::<Record>::new()
    .has_headers(true);

// Disable headers (all rows are data)
let builder = CsvItemReaderBuilder::<Record>::new()
    .has_headers(false);

pub fn from_reader<R: Read>(self, rdr: R) -> CsvItemReader<R>

Creates a CsvItemReader from a reader.

This allows reading CSV data from any source that implements the Read trait, such as files, strings, or network connections.

Parameters

• rdr: The reader containing CSV data

Configuration Applied

The following configurations are applied:

• Trims all whitespace from fields
• Uses specified delimiter (default: comma)
• Uses specified terminator (default: CRLF)
• Handles headers according to configuration
• Strict parsing (not flexible) to identify formatting issues

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use spring_batch_rs::core::item::ItemReader;
use serde::Deserialize;
use std::io::Cursor;

#[derive(Deserialize)]
struct Record {
    id: u32,
    name: String,
}

// Read from a string
let data = "id,name\n1,Alice\n2,Bob";
let reader = CsvItemReaderBuilder::<Record>::new()
    .has_headers(true)
    .from_reader(data.as_bytes());

// Or read from a Cursor
let cursor = Cursor::new("id,name\n1,Alice\n2,Bob");
let reader = CsvItemReaderBuilder::<Record>::new()
    .has_headers(true)
    .from_reader(cursor);

pub fn from_path<R: AsRef<Path>>(self, path: R) -> CsvItemReader<File>

Creates a CsvItemReader from a file path.

Parameters

• path: The path to the CSV file

Returns

A new CsvItemReader configured to read from the specified file

Panics

Panics if the file cannot be opened

Error Handling

This method panics immediately if the file cannot be opened, which is appropriate for initialization failures. Subsequent reading errors are returned as Result values from the read method.

Examples

use spring_batch_rs::item::csv::csv_reader::CsvItemReaderBuilder;
use spring_batch_rs::core::item::ItemReader;
use serde::Deserialize;

#[derive(Deserialize)]
struct Record {
    id: u32,
    name: String,
}

// Read from a file
let reader = CsvItemReaderBuilder::<Record>::new()
    .has_headers(true)
    .from_path("data.csv");

// Process records
let mut records: Vec<Record> = Vec::new();
while let Some(record) = ItemReader::<Record>::read(&reader).unwrap() {
    println!("ID: {}, Name: {}", record.id, record.name);
    records.push(record);
}

Trait Implementations

impl<I: Default> Default for CsvItemReaderBuilder<I>

fn default() -> CsvItemReaderBuilder<I>

Returns the “default value” for a type.