cligj 0.5.0

Arguments

files_in_arg Multiple files

files_inout_arg Multiple files, last of which is an output file.

features_in_arg GeoJSON Features input which accepts multiple representations of GeoJSON features and returns the input data as an iterable of GeoJSON Feature-like dictionaries

Options

verbose_opt

quiet_opt

format_opt

Example

Here’s an example of a command that writes out GeoJSON features as a collection or, optionally, a sequence of individual features. Since most software that reads and writes GeoJSON expects a text containing a single feature collection, that’s the default, and a LF-delimited sequence of texts containing one GeoJSON feature each is a feature that is turned on using the --sequence option. To write sequences of feature texts that conform to the JSON Text Sequences proposed standard (and might contain pretty-printed JSON) with the ASCII Record Separator (0x1e) as a delimiter, use the --rs option

import click
import cligj
import json

def process_features(features):
    for feature in features:
        # TODO process feature here
        yield feature

@click.command()
@cligj.features_in_arg
@cligj.sequence_opt
@cligj.use_rs_opt
def pass_features(features, sequence, use_rs):
    if sequence:
        for feature in process_features(features):
            if use_rs:
                click.echo(u'\x1e', nl=False)
            click.echo(json.dumps(feature))
    else:
        click.echo(json.dumps(
            {'type': 'FeatureCollection',
             'features': list(process_features(features))}))

On the command line, the generated help text explains the usage

Usage: pass_features [OPTIONS] FEATURES...

Options:
--sequence / --no-sequence  Write a LF-delimited sequence of texts
                            containing individual objects or write a single
                            JSON text containing a feature collection object
                            (the default).
--rs / --no-rs              Use RS (0x1E) as a prefix for individual texts
                            in a sequence as per http://tools.ietf.org/html
                            /draft-ietf-json-text-sequence-13 (default is
                            False).
--help                      Show this message and exit.

And can be used like this

$ cat data.geojson
{'type': 'FeatureCollection', 'features': [{'type': 'Feature', 'id': '1'}, {'type': 'Feature', 'id': '2'}]}

$ pass_features data.geojson
{'type': 'FeatureCollection', 'features': [{'type': 'Feature', 'id': '1'}, {'type': 'Feature', 'id': '2'}]}

$ cat data.geojson | pass_features
{'type': 'FeatureCollection', 'features': [{'type': 'Feature', 'id': '1'}, {'type': 'Feature', 'id': '2'}]}

$ cat data.geojson | pass_features --sequence
{'type': 'Feature', 'id': '1'}
{'type': 'Feature', 'id': '2'}

$ cat data.geojson | pass_features --sequence --rs
^^{'type': 'Feature', 'id': '1'}
^^{'type': 'Feature', 'id': '2'}

In this example, ^^ represents 0x1e.