如果需要監(jiān)視大型響應(yīng)的下載進度，可以使用響應(yīng)流式處理并檢查?response.num_bytes_downloaded?屬性。

正確確定下載進度需要此接口，因為如果使用 HTTP 響應(yīng)壓縮，則返回的總字節(jié)數(shù)?response.content?或?response.iter_content()?并不總是與響應(yīng)的原始內(nèi)容長度相對應(yīng)。

 注：下文的tqdm庫和rich庫都要使用pip進行安裝，可以使用 ?pip install tqdm? 來安裝tqdm庫，使用? pip install rich? 來安裝rich庫

例如，在下載響應(yīng)時使用tqdm庫顯示進度條可以像這樣完成...

import tempfile

import httpx
from tqdm import tqdm

with tempfile.NamedTemporaryFile() as download_file:
    url = "https://speed.hetzner.de/100MB.bin"
    with httpx.stream("GET", url) as response:
        total = int(response.headers["Content-Length"])

        with tqdm(total=total, unit_scale=True, unit_divisor=1024, unit="B") as progress:
            num_bytes_downloaded = response.num_bytes_downloaded
            for chunk in response.iter_bytes():
                download_file.write(chunk)
                progress.update(response.num_bytes_downloaded - num_bytes_downloaded)
                num_bytes_downloaded = response.num_bytes_downloaded

或者另一個例子，這次使用rich庫...

import tempfile
import httpx
import rich.progress

with tempfile.NamedTemporaryFile() as download_file:
    url = "https://speed.hetzner.de/100MB.bin"
    with httpx.stream("GET", url) as response:
        total = int(response.headers["Content-Length"])

        with rich.progress.Progress(
            "[progress.percentage]{task.percentage:>3.0f}%",
            rich.progress.BarColumn(bar_width=None),
            rich.progress.DownloadColumn(),
            rich.progress.TransferSpeedColumn(),
        ) as progress:
            download_task = progress.add_task("Download", total=total)
            for chunk in response.iter_bytes():
                download_file.write(chunk)
                progress.update(download_task, completed=response.num_bytes_downloaded)