Concurrent Upload

This example file covers the usage of the concurrent upload_files_gen method of the Client class. The key feature here is the way results are given back to the user; as a generator. This means that a result (as a job) is given back whenever it is finished, which likely is not the order of which they were uploaded.

Calling the script is similar to the Client example.

The files which are uploaded are restricted to FITS files, but this is not the case in general. If you want to make this example work for any file type (accepted by Astrometry.net), remove the usage of the enough_sources filter function, and then also remove the line containing filter(is_fits, ...). If you do this, you should be more careful not to include invalid files (or directories) when running the script.

An additional dependency of photutils is required in order to run this script: pip install photutils. This is used in the enough_sources function.

File can also be found at the source

#!/usr/bin/env python3
import logging
import os
from sys import argv

from astropy.io import fits
from astropy.stats import sigma_clipped_stats
from photutils import DAOStarFinder

from astrometry_net_client import Client

FMT = (
    "[%(asctime)s] %(threadName)-8s %(levelname)-8s |"
    " %(funcName)s - %(message)s"
)
logging.basicConfig(level=logging.INFO, format=FMT)
log = logging.getLogger(__name__)


def find_sources(filename, detect_threshold=20, fwhm=3):
    with fits.open(filename) as f:
        data = f[0].data
    # find sources
    mean, median, std = sigma_clipped_stats(data, sigma=3.0, maxiters=5)
    daofind = DAOStarFinder(fwhm=fwhm, threshold=detect_threshold * std)
    sources = daofind(data - median)
    return sources


def enough_sources(filename, min_sources=5):
    sources = find_sources(filename)
    # terminate if not enough are found.
    # sources is None when no sources are found
    num_sources = len(sources) if sources is not None else 0
    if sources is None or num_sources < min_sources:
        msg = "Not enough sources found: {} found, {} wanted."
        log.info(msg.format(num_sources, min_sources))
        return False
    log.info("Found {} sources".format(num_sources))
    return True


def is_fits(string):
    """
    Boolean function to test if the extension of the filename provided
    is either .fits or .fit (upper- or lowercase).

    Parameters
    ----------
    string: str
        (path to) filename to test

    Returns
    -------
    bool
    """
    string = string.upper()
    return string.endswith(".FITS") or string.endswith(".FIT")


def change_filename(filename):
    """
    Generate new filename to avoid overwriting an existing file
    change: ``path/to/file.fits``
    into  : ``path/to/file.astrom.fits``

    Parameters
    ----------
    filename: str
        The full path to the file which is to be changed

    Returns
    -------
    str
        The new path to the given filename
    """
    path, name = os.path.split(filename)
    res_filename = name.split(".")
    res_filename.insert(-1, "astrom")
    res_filename = ".".join(res_filename)
    return os.path.join(path, res_filename)


def main():
    if len(argv) < 3:
        print("Usage:")
        print(
            " $ python3 client.py [path/to/key/file] "
            "[file1 file2 file3 ... fileN]"
        )
        exit(-1)

    key_location, *files = argv[1:]

    log.info("Initializing client (loggin in)")
    c = Client(key_location=key_location)
    log.info("Log in done")

    # iterate over all the fits files in the specified diretory
    fits_files = filter(is_fits, files)

    # give the iterable of filenames to the function, which returns a
    # generator, generating pairs containing the finished job and filename.
    result_iter = c.upload_files_gen(
        fits_files, filter_func=enough_sources, filter_args=(10,)
    )

    for job, filename in result_iter:

        if not job.success():
            log.info("File {} Failed".format(filename))
            continue

        # retrieve the wcs file from the successful job
        wcs = job.wcs_file()
        with fits.open(filename) as hdul:
            # append resulting header (with astrometry) to existing header
            hdul[0].header.extend(wcs)

            write_filename = change_filename(filename)

            log.info("Writing to {}...".format(write_filename))
            try:
                hdul.writeto(write_filename)
            except Exception:
                log.error("File {} already exists.".format(write_filename))


if __name__ == "__main__":
    main()