commit cbc9f47a1775418a07dbdd8c7df50c25970fe7e2
Author: fordprefect <fordprefect@dukun.de>
Date:   Wed Mar 25 19:22:18 2020 +0100

    basic search function in Nominatim with output to GPX file

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..0e013fb
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+__pycache__
+*gpx
diff --git a/find_WWR_and_output_as_gpx.py b/find_WWR_and_output_as_gpx.py
new file mode 100644
index 0000000..11c9538
--- /dev/null
+++ b/find_WWR_and_output_as_gpx.py
@@ -0,0 +1,87 @@
+"""
+Script to retrieve all Openstreetmap items matching a query and save
+them as GPX Waypoints to a given output file in GPX format.
+"""
+
+__author__ = "fordprefect"
+__date__ = "2020-03-2
+__version__ = "0.1"
+
+import gpxpy
+import requests
+import os
+import sys
+assert sys.version_info >= (3, 6), "At least Python 3.8 required due to fStrings. Replace all f\"…\" and comment this line to enable running in lower versions (but really, you should just update your Python version…)."
+
+#####################################
+######## configuration
+#####################################
+
+# search url of nominatim (don't change if you don't know what you are doing!)
+url = "https://nominatim.openstreetmap.org/search/"
+
+# search arguments, change query here
+# for all supported keys see http://nominatim.org/release-docs/latest/api/Search/
+args = {"q": "Wasserwanderplatz", "country": "Germany", "format": "json", "limit": 50}
+
+# bounding box defined by two points [x1, y1, x2, y2]
+use_boundingbox = True
+boundingbox = [53.898, 11.338, 52.700, 14.332]
+
+# output file name
+gpxfilename = f"nominatimsearch_{args['q']}.gpx"
+
+# OSM IDs to be ignored (used to find all matching items)
+ignore_ids = []
+
+# maximum number of search queries
+maxsearchnums = 10
+
+# verbosity
+verbosity = 0
+
+#####################################
+######## end of configuration
+#####################################
+
+## initialize gpx file
+if os.path.isfile(gpxfilename):
+    # open file and parse
+    if verbosity > 0: print(f"found file, extending")
+    gpxfile = gpxpy.parse(open(gpxfilename, "r"))
+else:
+    if verbosity > 0: print("creating new file")
+    gpxfile = gpxpy.gpx.GPX()
+
+# search loop
+for i in range(maxsearchnums):
+    # fetch request
+    if use_boundingbox:
+        args["viewbox"] = ",".join(list(map(str, boundingbox)))
+    if ignore_ids != []:
+        args["exclude_place_ids"] = ",".join(list(map(str, ignore_ids)))
+    r = requests.get(url + "?" + "&".join([f"{key}={args[key]}" for key in args]))
+
+    if r.status_code != 200:
+        if verbosity > 0: print(f"Query gone wrong: HTTP returned {r.status_code}")
+        exit(1)
+
+    # parse reply
+    reply = r.json()
+    assert isinstance(reply, list), "Unexpected type of reply: " + type(reply)
+    if len(reply) == 0:
+        if verbosity > 0: print(f"found {len(ignore_ids)} results in {i-1} iterations, finishing")
+        break
+
+    for point in reply:
+        pid = point["place_id"]
+        ignore_ids.append(pid)
+        lat = point["lat"]
+        lon = point["lon"]
+        name = point["display_name"]
+        gpxfile.waypoints.append(gpxpy.gpx.GPXWaypoint(latitude=lat, longitude=lon, name=name))
+
+# save to disk
+with open(gpxfilename, "w") as f:
+    f.write(gpxfile.to_xml())
+if verbosity > 0: print(f"GPX file written to {gpxfilename}")