refactoring, object oriented. CLI interface needs polishing

osmsearch.py

@@ -0,0 +1,100 @@
+#!/usr/bin/python
+"""
+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__ = "2020-03-26"
+__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…)."
+
+class OSMSearch():
+    def __init__(self, args): 
+        self.url = args.pop("url")
+        self.maxsearchnums = args.pop("maxsearchnums")
+        self.gpxfilename = args.pop("outputfilename")
+        self.use_boundingbox = args.pop("use_boundingbox")
+        if self.use_boundingbox:
+            assert isinstance(list, args["boundingbox"])
+            assert len(args["boundingbox"]) == 4
+        else:
+            args.pop("boundingbox")
+
+        self.searchargs = args
+
+        self.initialize_gpx_file()
+
+        self.search()
+
+        self.save_to_disk()
+ 
+    def initialize_gpx_file(self):
+        if os.path.isfile(self.gpxfilename):
+            # open file and parse
+            #if verbosity > 0: print(f"found file, extending")
+            self.gpxfile = gpxpy.parse(open(gpxfilename, "r"))
+        else:
+            #if verbosity > 0: print("creating new file")
+            self.gpxfile = gpxpy.gpx.GPX()
+
+    def get_argstring(self):
+        argstrings = []
+
+        if self.use_boundingbox:
+            argstring.append(",".join(list(map(str, self.searchargs["boundingbox"]))))
+        for arg in self.searchargs:
+            argstrings.append(f"{arg}={self.searchargs[arg]}")
+
+        return "?"+"&".join(argstrings)
+
+
+    def search(self):
+        """
+        """
+
+        for i in range(self.maxsearchnums):
+            # fetch request
+            r = requests.get(self.url + self.get_argstring())
+
+            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:
+                self.searchargs["ignore_ids"].append(point["place_id"])
+                self.gpxfile.waypoints.append(gpxpy.gpx.GPXWaypoint(latitude=point["lat"], longitude=point["lon"], name=point["display_name"]))
+
+    def save_to_disk(self):
+        with open(self.gpxfilename, "w") as f:
+            f.write(self.gpxfile.to_xml())
+        #if verbosity > 0: print(f"GPX file written to {gpxfilename}")
+
+default_args = {
+    "q": "Camping",
+    "format": "json",
+    "limit": 50,
+    "use_boundingbox": False,
+    "boundingbox": [],
+    "outputfilename": "test.gpx",
+    "ignore_ids": [],
+    "maxsearchnums": 10,
+    "url": "https://nominatim.openstreetmap.org/search/",
+}
+
+if __name__ == "__main__":
+    # cli invocation goes here
+    # TODO: take user arguments and bring together with sensible defaults above
+    OSMSearch(default_args)