Exporting data as ‘as-is’

This example shows how to submit an ‘url_quick’ / ‘as-is’ data export request to JSOC and how to download the requested files.

The export protocol ‘as-is’, should be preferred over other protocols, because it minimizes the server load. The only reason to use protocol=’fits’ is, when keywords in the FITS header are really needed.

import os
from pathlib import Path

import drms

First we will create a drms.Client, using the JSOC baseurl.

client = drms.Client()

# This example requires a registered export email address. You can register
# JSOC exports at: http://jsoc.stanford.edu/ajax/register_email.html
# You must supply your own email.
email = os.environ["JSOC_EMAIL"]

# Create download directory if it does not exist yet.
out_dir = Path("downloads")
if not out_dir.exists():
    Path(out_dir).mkdir(parents=True)

Traceback (most recent call last):
  File "/home/docs/checkouts/readthedocs.org/user_builds/drms/checkouts/stable/examples/export_as_is.py", line 27, in <module>
    email = os.environ["JSOC_EMAIL"]
            ~~~~~~~~~~^^^^^^^^^^^^^^
  File "<frozen os>", line 679, in __getitem__
KeyError: 'JSOC_EMAIL'

Construct the DRMS query string: “Series[harpnum][timespan]{data segments}”

qstr = "hmi.sharp_720s[7451][2020.09.27_00:00:00_TAI]{continuum, magnetogram, field}"
print(f"Data export query:\n  {qstr}\n")

# Submit export request, defaults to method='url_quick' and protocol='as-is'
print("Submitting export request...")
result = client.export(qstr, email=email)
print(f"{int(len(result.urls))} file(s) available for download.\n")

# Download selected files.
result.download(out_dir)
print("Download finished.")
print(f'\nDownload directory:\n  "{out_dir.resolve()}"\n')