def lookup_point(request):
"""Find nearby polygons with a point and search radius.
Three lookup methods are supported:
sphericalmercator: radius (in km) is applied to search buffer in
900913 (aka Google Spherical Mercator) projection. This method
is appropriate when used in conjuction with web maps.
greatcircle: uses PostGIS ST_DWithin spatial query on a geography
column, using great circle distances.
point: simple test if point is inside polygons (e.g., radius=0)
These methods assume the geometries are in a Geography column. Edge
cases across the dateline are handled correctly.
Different methods are needed if a regular Geometry column is used
in order to handle cases across the dateline."""
mpa_list = ()
default_method = 'webmercator'
try:
lon = float(request.GET['lon'])
lat = float(request.GET['lat'])
try:
radius = float(request.GET['radius'])
except:
radius = 225.0 # km
try:
method = request.GET['method'] or default_method # set default if empty string passed
except (KeyError):
method = default_method
if method not in ('point', 'greatcircle', 'webmercator', 'webmercator_buffer', 'webmercator_box', 'webmercator_simple'):
raise LookupMethodError('Unknown or malformed lookup method passed in GET query string.')
if (radius == 0):
method = 'point'
except:
# Bad input, return empty list
return render(request, 'mpa/mpalookup.json', {
'mpa_list': mpa_list,
}, content_type='application/json; charset=utf-8')
else:
mpas_valid = mpas_norejects_nogeom
# We need to normalize the longitude into the range -180 to 180 so we don't
# make the cast to PostGIS Geography type complain
point = geos.Point(normalize_lon(lon), lat, srid=gdal.SpatialReference('WGS84').srid) # srid=4326 , WGS84 geographic
origpoint = point.clone()
if (method == 'webmercator'):
if (normalize_lon(lon) < 0):
lon360 = normalize_lon(lon) + 360
else:
lon360 = normalize_lon(lon) - 360
point360 = geos.Point(lon360, lat, srid=gdal.SpatialReference('WGS84').srid)
point.transform(3857) # Google Spherical Mercator srid
point360.transform(3857)
#mpa_list = Mpa.objects.filter(geom_smerc__dwithin=(point, Distance(km=radius))).defer(*Mpa.get_geom_fields())
mpa_list = mpas_valid.filter(Q(geom_smerc__dwithin=(point, Distance(km=radius))) | Q(geom_smerc__dwithin=(point360, Distance(km=radius)))).defer(*Mpa.get_geom_fields())
search = point
elif (method == 'webmercator_buffer'):
point.transform(3857) # Spherical Mercator srid
searchbuffer = point.buffer(radius * 1000) # convert km to m, create buffer
mpa_list = mpas_valid.filter(geog__intersects=searchbuffer).defer(*Mpa.get_geom_fields())
search = searchbuffer
elif (method == 'webmercator_box'):
point.transform(3857) # Spherical Mercator srid
searchbuffer = point.buffer(radius * 1000)
mpa_list = mpas_valid.filter(geog__intersects=searchbuffer.envelope).defer(*Mpa.get_geom_fields()) # use simple bounding box instead
search = searchbuffer.envelope
elif (method == 'webmercator_simple'):
point.transform(3857) # Spherical Mercator srid
searchbuffer = point.buffer(radius * 1000, quadsegs=2) # simple buffer with 2 segs per quarter circle
mpa_list = mpas_valid.filter(geog__intersects=searchbuffer).defer(*Mpa.get_geom_fields())
search = searchbuffer
elif (method == 'greatcircle'):
mpa_list = mpas_valid.filter(geog__dwithin=(point, Distance(km=radius))).defer(*Mpa.get_geom_fields())
search = point
elif (method == 'point'):
mpa_list = mpas_valid.filter(geog__intersects=point).defer(*Mpa.get_geom_fields())
search = point
candidate_radius = radius * 2.2 # We're using big icons on a point, this let's us catch it better
mpa_point_list = mpas_norejects_nogeom.filter(is_point=True, point_geog__dwithin=(origpoint, Distance(km=candidate_radius)))
#mpa_candidate_list = mpas_proposed_nogeom
# mpa_list = list(mpa_list)
# ids = [m.mpa_id for m in mpa_list]
# cleaned_mpa_list
# for mpa in mpa_list:
# if mpa.mpa_id >= 7700000:
# orig_id = int(str(mpa_id)[-5:])
# if orig_id in ids:
# ids.remove(orig_id)
# for mpa in mpa_list:
# if mpa.mpa_id in ids:
# cleaned_mpa_list.append(mpa)
search.transform(4326)
return render(request, 'mpa/mpalookup.json', {
'search': search.coords,
'mpa_list': mpa_list | mpa_point_list, # this joins the query sets with an OR
}, content_type='application/json; charset=utf-8')
from mpa.forms import MpaForm, MpaGeomForm
from mpa.filters import apply_filters
#import reversion
from reversion import revisions as reversion
from django.db import connection, transaction
from reversion.models import Revision
from mpa.models import Mpa, Contact, WikiArticle, VersionMetadata
from django.views.decorators.cache import never_cache
from django.contrib.auth.decorators import login_required
# Predefined querysets
mpas_norejects = Mpa.objects.exclude(verification_state='Rejected as MPA')
mpas_norejects_nogeom = mpas_norejects.defer(*Mpa.get_geom_fields())
mpas_all_nogeom = Mpa.objects.all().defer(*Mpa.get_geom_fields())
mpas_noproposed_nogeom = mpas_norejects.exclude(status='Proposed').defer(*Mpa.get_geom_fields())
mpas_proposed_nogeom = mpas_norejects.filter(status='Proposed').defer(*Mpa.get_geom_fields())
def do_revision(request):
mpa = Mpa.objects.get(pk=4)
mpa.summary = 'Test123'
mpa.save()
reversion.set_comment('Test comment')
@never_cache
@transaction.atomic
@reversion.create_revision()
def revision_view(request):
do_revision(request)
def get_mpa_geom_json(request, pk, simplified=True, webmercator=False):
try:
simplified = request.GET['simplified'].lower() not in ('false', 'f', 'no', '0', 0)
except:
pass
try:
webmercator = (request.GET['webmercator'].upper() == 'TRUE')
except:
pass
geomfield = sgeomfield = 'geom'
if (webmercator):
geomfield = 'geom_smerc'
mpaq = Mpa.objects.geojson(field_name=geomfield).geojson(field_name='point_within', model_att='geojson_point').defer(*Mpa.get_geom_fields())
if simplified:
sgeomfield = 'simple_' + geomfield
mpaq = mpaq.geojson(field_name=sgeomfield, model_att='geojson_simple')
mpa = mpaq.get(pk=pk)
if mpa.is_point:
geojson = mpa.geojson_point
else:
geojson = mpa.geojson if not simplified else mpa.geojson_simple
if not geojson and simplified:
geojson = mpa.geojson
return HttpResponse(geojson or '{}', content_type='application/json; charset=utf-8')
def removeUsaFromQuerySet(qs=None):
if qs is None:
qs = Mpa.objects.all().defer(*Mpa.get_geom_fields())
return qs.exclude(country__in=UsaCodes)
