Function syncFetch

packages/runtime-python/src/webworker.ts:110–168

(method: string, url: string, headers: any, body: any)

}

const syncFetch = (method: string, url: string, headers: any, body: any): ResponseData => {
  let objHeaders = {}
  let bodyArray: Uint8Array | string = null
  if (pyodide.isPyProxy(headers) && headers.type === 'dict') {
    objHeaders = headers.toJs({ dict_converter: Object.fromEntries })
  }
  if (typeof body === 'string') {
    bodyArray = body
  } else if (pyodide.isPyProxy(body) && body.type === 'bytes') {
    bodyArray = body.toJs() as Uint8Array
  }

  if (rerun) {
    return replayFetch({ method, url, headers: objHeaders, body: bodyArray })
  }

  sendMessage({
    type: 'fetch',
    data: {
      method: method,
      url: url,
      headers: objHeaders,
      body: bodyArray,
    },
  })
  const res = Atomics.wait(fetchBufferMeta, 0, 0)
  if (res === 'timed-out') {
    // TODO: Support request timeout
  }
  const headerSize = Atomics.exchange(fetchBufferMeta, 1, 0)
  const bodySize = Atomics.exchange(fetchBufferMeta, 2, 0)
  const totalSize = headerSize + bodySize
  let buffer: Uint8Array
  if (totalSize <= fetchBuffer.length) {
    buffer = fetchBuffer
    Atomics.store(fetchBufferMeta, 0, 0)
  } else {
    let bytesRead = 0
    buffer = new Uint8Array(totalSize)
    while (bytesRead < totalSize) {
      const toRead = Math.min(totalSize - bytesRead, fetchBuffer.length)
      buffer.set(fetchBuffer.subarray(0, toRead), bytesRead)
      bytesRead += toRead
      Atomics.store(fetchBufferMeta, 0, 0)
      if (bytesRead < totalSize) {
        sendMessage({ type: 'continueFetch' })
        Atomics.wait(fetchBufferMeta, 0, 0)
      }
    }
  }
  const bytes = buffer.slice(0, headerSize)
  const contentBytes = buffer.slice(headerSize, headerSize + bodySize)

  const decoder = new TextDecoder()
  const textJSON = decoder.decode(bytes)
  const result = JSON.parse(textJSON) as ResponseData
  result.body = contentBytes
  return result