Add JSON output

kosmorro

@@ -18,21 +18,13 @@
 
 import argparse
 from datetime import date
-import numpy
 from kosmorrolib import dumper
 from kosmorrolib.ephemerides import EphemeridesComputer, Position
 
 
-# Fixes the "TypeError: Object of type int64 is not JSON serializable"
-# See https://stackoverflow.com/a/50577730
-def json_default(obj):
-    if isinstance(obj, numpy.int64):
-        return int(obj)
-    raise TypeError('Object of type ' + str(type(obj)) + ' could not be integrated in the JSON')
-
-
 def main():
-    args = get_args()
+    output_formats = get_dumpers()
+    args = get_args(list(output_formats.keys()))
     year = args.year
     month = args.month
     day = args.day
@@ -43,11 +35,18 @@ def main():
     ephemeris = EphemeridesComputer(Position(args.latitude, args.longitude, altitude=args.altitude))
     ephemerides = ephemeris.compute_ephemerides(year, month, day)
 
-    dump = dumper.TextDumper(ephemerides)
+    dump = output_formats[args.format](ephemerides)
     print(dump.to_string())
 
 
-def get_args():
+def get_dumpers() -> {str: dumper.Dumper}:
+    return {
+        'text': dumper.TextDumper,
+        'json': dumper.JsonDumper
+    }
+
+
+def get_args(output_formats: [str]):
     today = date.today()
 
     parser = argparse.ArgumentParser(description='Compute the ephemerides for a given date, at a given position'
@@ -56,6 +55,8 @@ def get_args():
                                             ' observer positioned at coordinates (0,0), with an altitude of 0.'
                                      % today.strftime('%a %b %d, %Y'))
 
+    parser.add_argument('--format', '-f', type=str, default=output_formats[0], choices=output_formats,
+                        help='The format under which the information have to be output')
     parser.add_argument('--latitude', '-lat', type=float, default=0.,
                         help="The observer's latitude on Earth")
     parser.add_argument('--longitude', '-lon', type=float, default=0.,

kosmorrolib/data.py

@@ -22,6 +22,18 @@ from typing import Union
 from skyfield.api import Topos
 from skyfield.timelib import Time
 
+MOON_PHASES = {
+    'NEW_MOON': 'New Moon',
+    'FIRST_QUARTER': 'First Quarter',
+    'FULL_MOON': 'Full Moon',
+    'LAST_QUARTER': 'Last Quarter'
+}
+
+
+def skyfield_to_moon_phase(val: int) -> str:
+    phases = list(MOON_PHASES.keys())
+    return phases[val]
+
 
 class Position:
     def __init__(self, latitude: float, longitude: float, altitude: float = 0):

kosmorrolib/dumper.py

@@ -18,9 +18,11 @@
 
 from abc import ABC, abstractmethod
 import datetime
+import json
 from tabulate import tabulate
-from skyfield import almanac
+from skyfield.timelib import Time
-from .data import Object
+from numpy import int64
+from .data import Object, AsterEphemerides, MOON_PHASES
 
 
 class Dumper(ABC):
@@ -33,6 +35,30 @@ class Dumper(ABC):
         pass
 
 
+class JsonDumper(Dumper):
+    def to_string(self):
+        return json.dumps(self.ephemeris,
+                          default=self._json_default,
+                          indent=4)
+
+    @staticmethod
+    def _json_default(obj):
+        # Fixes the "TypeError: Object of type int64 is not JSON serializable"
+        # See https://stackoverflow.com/a/50577730
+        if isinstance(obj, int64):
+            return int(obj)
+        if isinstance(obj, Time):
+            return obj.utc_iso()
+        if isinstance(obj, Object):
+            obj = obj.__dict__
+            obj.pop('skyfield_name')
+            return obj
+        if isinstance(obj, AsterEphemerides):
+            return obj.__dict__
+
+        raise TypeError('Object of type "%s" could not be integrated in the JSON' % str(type(obj)))
+
+
 class TextDumper(Dumper):
     def to_string(self):
         return '\n\n'.join(['Ephemerides of %s' % self.date.strftime('%A %B %d, %Y'),
@@ -69,4 +95,4 @@ class TextDumper(Dumper):
 
     @staticmethod
     def get_moon(moon):
-        return 'Moon phase: %s' % almanac.MOON_PHASES[moon['phase']]
+        return 'Moon phase: %s' % MOON_PHASES[moon['phase']]

kosmorrolib/ephemerides.py

@@ -20,7 +20,7 @@ import datetime
 from skyfield import almanac
 from skyfield.timelib import Time
 
-from .data import Object, Position, AsterEphemerides
+from .data import Object, Position, AsterEphemerides, skyfield_to_moon_phase
 from .core import get_skf_objects, get_timescale, ASTERS, MONTHS
 
 RISEN_ANGLE = -0.8333
@@ -48,7 +48,7 @@ class EphemeridesComputer:
 
         _, moon_phase = almanac.find_discrete(time1, time2, almanac.moon_phases(get_skf_objects()))
 
-        return {'phase': moon_phase[-1]}
+        return {'phase': skyfield_to_moon_phase(moon_phase[-1])}
 
     @staticmethod
     def get_asters_ephemerides_for_aster(aster, date: datetime.date, position: Position) -> Object: