Struct JsonLinesWriter 

pub struct JsonLinesWriter<W: Write> { /* private fields */ }

Streaming writer for JSONL format

Writes HEDL documents as newline-delimited JSON for efficient streaming.

Format

Each document is written as a single JSON object followed by newline:

{"id":"1","name":"Alice"}
{"id":"2","name":"Bob"}

Examples

use hedl_json::streaming::JsonLinesWriter;
use hedl_core::Document;
use std::io::Cursor;

# fn example() -> Result<(), Box<dyn std::error::Error>> {
let mut buffer = Vec::new();
let mut writer = JsonLinesWriter::new(&mut buffer);

let doc1 = Document::new((2, 0));
writer.write_document(&doc1)?;

let doc2 = Document::new((2, 0));
writer.write_document(&doc2)?;

writer.flush()?;
# Ok(())
# }

Implementations

impl<W: Write> JsonLinesWriter<W>

pub fn new(writer: W) -> Self

Create a new JSONL writer

Arguments

• writer - Output destination

Examples

use hedl_json::streaming::JsonLinesWriter;
use std::fs::File;

# fn example() -> Result<(), Box<dyn std::error::Error>> {
let file = File::create("output.jsonl")?;
let mut writer = JsonLinesWriter::new(file);
# Ok(())
# }

pub fn write_document(&mut self, doc: &Document) -> Result<(), StreamError>

Write a HEDL document as a JSONL entry

Converts the document to JSON and writes it followed by a newline.

Errors

Returns error if JSON conversion or I/O write fails.

Examples

use hedl_json::streaming::JsonLinesWriter;
use hedl_core::Document;

# fn example() -> Result<(), Box<dyn std::error::Error>> {
let mut buffer = Vec::new();
let mut writer = JsonLinesWriter::new(&mut buffer);

let doc = Document::new((2, 0));
writer.write_document(&doc)?;
# Ok(())
# }

pub fn flush(&mut self) -> Result<(), StreamError>

Flush the output buffer

Ensures all data is written to the underlying writer.

Examples

use hedl_json::streaming::JsonLinesWriter;
use hedl_core::Document;

# fn example() -> Result<(), Box<dyn std::error::Error>> {
let mut buffer = Vec::new();
let mut writer = JsonLinesWriter::new(&mut buffer);

let doc = Document::new((2, 0));
writer.write_document(&doc)?;
writer.flush()?;
# Ok(())
# }