Adding native parsers between geojson and shapefiles

gis_utils/in_parsers/__init__.py

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+from .geojson_to_shp import geojson_to_shp
+from .shp_to_geojson import shp_to_geojson

gis_utils/in_parsers/geojson_to_shp.py

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+import os 
+import geojson
+import shapefile
+import multiprocessing as mp
+
+def geojson_to_shp(geojson_file_name,shp_file_name=None):
+    """
+    Converts a geojson file into a shapefile. This is a serial process
+    """
+    if shp_file_name == None:
+        shp_file_name = geojson_file_name.split(os.path.sep)[-1].split(".")[0]
+
+    # Open the GeoJSON and load it to memory
+    geoj = geojson.load(open(geojson_file_name,"r"))
+
+    w = shapefile.Writer()
+
+    # Get the number of features
+    features = len(geoj["features"])
+
+    i = 0
+    while i < features:
+        # Paranoid to prevent exceptions u
+        try:
+            w.shape(geoj[i]["geometry"])
+        except:
+            break
+        i += 1
+
+    w.save('test.shp')

gis_utils/in_parsers/shp_to_geojson.py

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+import os
+import json
+import shapefile
+import multiprocessing as mp
+
+def FeatureCollection(features):
+    """
+    FeatureCollection creates a `FeatureCollection` with the 
+    features in `features`
+    """
+    return {"type": "FeatureCollection","features": features}
+    # return {"type": "FeatureCollection","properties":{"features": len(features)},"features": features}
+
+
+def Feature(iterator):
+    """
+    Generates a feature provided the iterator `iterator` that 
+    implements the __geo__interface__
+    """
+    return {"type":"Feature", "geometry":iterator.__geo_interface__}
+
+
+def shp_to_geojson(shp_file_name,geojson_file_name=None):
+    """
+    Converts a shp file into a geojson file. This 
+    uses multiprocessing to critically accelerate the process.
+    """
+    # If no geojson_file_name is passed, use the shp_file_name without extension
+    if geojson_file_name == None:
+        geojson_file_name = shp_file_name.split(os.path.sep)[-1].split(".")[0]
+
+    shpfile = shapefile.Reader(shp_file_name)
+
+    pool = mp.Pool()
+    features = pool.map(Feature,shpfile.iterShapes())
+
+    f = open(geojson_file_name,"w")
+    f.write(json.dumps(FeatureCollection(features),indent=2))
+    f.close()