Streaming JSON Parsing

Streaming JSON

For large JSON files, streaming parsers process data incrementally without loading the entire file into memory.

Example

// Using the Streams API + TextDecoder for NDJSON
const response = await fetch("https://api.example.com/stream");
const reader = response.body.getReader();
const decoder = new TextDecoder();

while (true) {
  const { done, value } = await reader.read();
  if (done) break;
  const lines = decoder.decode(value).split("
");
  for (const line of lines) {
    if (line) {
      const item = JSON.parse(line); // Newline-delimited JSON
      processItem(item);
    }
  }
}

JAVASCRIPT

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Pro Tip

Newline-delimited JSON (NDJSON) is a simple format for streaming — one JSON object per line.

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