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Script to merge a GPX file into a KML file.
"""Imports a GPX file into the canonical KML file."""
import os
import sys
import traceback
import gpxpy
import simplekml
from datetime import datetime, timezone
from dateutil.parser import parse
from lxml import etree
# This script will generate both a KML file (to act as the canonical
# storage for driving data in a human readible format) and a KMZ file
# (to have a smaller filesize for loading over a network). The KML file
# will be read when merging new data.
KML_PATH = "Driving.kml"
KMZ_PATH = "Driving.kmz"
def main(argv):
"""Merges a GPX file into existing KML data."""
try:
input_gpx_file = argv[1]
except IndexError:
raise SystemExit(f"Usage: {argv[0]} <tracks.gpx>")
existing_tracks = kml_to_dict(KML_PATH)
new_tracks = gpx_to_dict(input_gpx_file)
# Merge existing tracks with gpx tracks. Existing tracks should
# override new tracks with same timestamp.
print("Merging new tracks into existing tracks …")
merged = {**new_tracks, **existing_tracks}
print("Creating KML/KMZ files …")
print(f"{len(new_tracks)} new tracks")
print(f"{len(merged)} merged tracks")
kml = simplekml.Kml()
kml.document.name = "Driving"
track_style = simplekml.Style()
track_style.linestyle.color = simplekml.Color.red
track_style.linestyle.width = 4
for timestamp, values in sorted(merged.items()):
line = kml.newlinestring(
name=timestamp.strftime("%Y-%m-%d %H:%M:%SZ"),
tessellate=1,
description=values['description'],
coords=values['coords']
)
line.style = track_style
line.timestamp = simplekml.TimeStamp(when=timestamp.isoformat())
kml.save(KML_PATH)
print(f"Saved KML to {KML_PATH}!")
kml.savekmz(KMZ_PATH)
print(f"Saved KMZ to {KMZ_PATH}!")
def kml_to_dict(kml_file):
"""
Reads the supplied KML file and returns a dictionary with datetime
keys and descriptions/coordinates (lists of (lon,lat,ele) tuples) as
values.
"""
print(f"Reading KML from {kml_file} …")
track_dict = {}
try:
root = etree.parse(KML_PATH).getroot()
nsmap = {None: "http://www.opengis.net/kml/2.2"}
for e in root.findall("./Document/Placemark", nsmap):
timestamp = parse(e.find("TimeStamp/when", nsmap).text)
timestamp = timestamp.astimezone(timezone.utc)
raw_coords = e.find("LineString/coordinates", nsmap).text.strip()
coords = list(
tuple(
float(n) for n in c.split(",")
) for c in raw_coords.split(" ")
)
desc = e.find("description", nsmap)
if desc is not None:
print("found description")
desc = desc.text.strip()
track_dict[timestamp] = dict(coords=coords, description=desc)
except OSError:
print(f"Could not open {KML_PATH}.")
os.system("pause")
print(f"Found {len(track_dict)} tracks!")
return track_dict
def gpx_to_dict(gpx_file):
"""
Reads the supplied GPX file and returns a dictionary with datetime
keys and descriptions/coordinates (lists of (lon,lat,ele) tuples) as
values.
"""
print(f"Reading GPX from {gpx_file} …")
gpx_file = open(gpx_file)
gpx = gpxpy.parse(gpx_file)
track_dict = {}
for track in gpx.tracks:
print(f"Converting {track.name}")
desc = track.description
for segment in track.segments:
try:
timestamp = segment.points[0].time.astimezone(timezone.utc)
except AttributeError:
timestamp = parse(track.name).astimezone(timezone.utc)
coords = list(
(p.longitude, p.latitude, p.elevation) for p in segment.points
)
track_dict[timestamp] = dict(coords=coords, description=desc)
return track_dict
if __name__ == "__main__":
try:
main(sys.argv)
except BaseException:
print(sys.exc_info()[0])
print(traceback.format_exc())
finally:
os.system("pause")
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