Draft: Chunk up large orders in planet orders request

[jreiberkyle]

Chunk up large orders in planet orders request directly from a search.

Note: planet orders create would also have to be able to take in multiline input, as planet orders request would now output one line for each order chunk. How to do it is already demonstrated, we just have to work out the UI.

The script below is a slight alteration of the example script in #944. It demonstrates how to do a version of this:

$> planet data search --limit 500 PSScene | python ml.py --items - --chunksize=300
500
chunk: 300
chunk: 200

ml.py

import json

import click


class MultiJSON(click.ParamType):
    name = 'MultiJSON'

    def convert(self, value, param, ctx) -> list:
        if isinstance(value, list):
            conv = value
        else:
            # read from raw json
            # skip this if value is a Path object or something else
            if isinstance(value, str) and (value.startswith('{')
                                           or value.startswith('[')):
                print('hereh')
                try:
                    conv = json.loads(value)
                    if isinstance(conv, dict):
                        conv = [conv]

                except json.decoder.JSONDecodeError:
                    self.fail(
                        'JSON string is not valid JSON. Make sure the entire '
                        'JSON string is single-quoted and string entries are '
                        'double-quoted.')

            # read from stdin or file
            else:
                try:
                    with click.open_file(value) as f:
                        conv = [json.loads(line) for line in f if line]
                except FileNotFoundError:
                    self.fail('File not found.')
                except json.decoder.JSONDecodeError:
                    stream = 'stdin' if value == '-' else 'JSON file'
                    self.fail(f'{stream} does not contain valid JSON.')

        if not len(conv):
            self.fail('JSON cannot be empty.')

        return conv


@click.command()
@click.option('--items', type=MultiJSON(), required=True)
@click.option('--chunksize', type=int, default=5)
def hello(items, chunksize):
    click.echo(len(items))

    # https://stackoverflow.com/a/312464
    def chunks(lst, n):
        """Yield successive n-sized chunks from lst."""
        for i in range(0, len(lst), n):
            yield lst[i:i + n]
    
    for chunk in chunks(items, chunksize):
        click.echo(f'chunk: {len(chunk)}')


if __name__ == '__main__':
    hello()