Sails js and GeoJSON format - javascript

anybody knows how to store GEOJSON in sails js models?
i want to store features and points in sails js models.
var geojsonFeature = {
"type": "Feature",
"properties": {
"name": "Coors Field",
"amenity": "Baseball Stadium",
"popupContent": "This is where the Rockies play!"
},
"geometry": {
"type": "Point",
"coordinates": [-104.99404, 39.75621]
}
};

In Sails' Attributes documentation you can find that there are 5 types supported by Sail's Waterline (the underlying ORM within Sails)
string
number
boolean
json
ref
In your case, you have several objects embedded. Something like the following would probably work:
attributes: {
type: {
type: 'string',
enum: ['Feature','This','That','Other'], // not required...
},
properties: {
type: 'json'
},
geometry: {
type: 'json'
}
}

Related

HereMaps GeoJSON Polygon click read properties

my question is as follows.
What I have
I have a GeoJSON feature collection with Polygons and custom properties
GeoJSON is loaded into the Here maps
What I want
I want to detect a polygon click and read the custom property value
Example GeoJSON
{
"type": "FeatureCollection",
"features": [{
"type": "Feature",
"properties": {
"customProp": "heyImACustomProperty"
},
"geometry": {
"type": "Polygon",
"coordinates": [
[
[
16.45477294921875,
43.51619059561274
],
[
16.450481414794922,
43.50772499687011
],
[
16.470909118652344,
43.5019975949657
],
[
16.481552124023438,
43.51021500212034
],
[
16.475543975830078,
43.518306809754804
],
[
16.45477294921875,
43.51619059561274
]
]
]
}
}]
}
Docs on GeoJSON manipulation are not the greatest.
Thanks in advance.
Here is the example code to get the property value of the GeoJSON Polygon on click.
reader = new H.data.geojson.Reader('/path/to/geojson/file.json');
reader.parse();
map.addLayer(reader.getLayer());
reader.getLayer().getProvider().addEventListener("tap", function(e) {
if(e.target instanceof H.map.Polygon) {
console.log('Custom property value: ', e.target.getData().properties.customProp);
}
});
GeoJSON documentation can be found here:
https://developer.here.com/documentation/maps/topics_api/h-data-geojson-reader.html

Rails jBuilder from GeoJSON to make another json

I'm trying to take a series of GeoJSON Line Strings and put them on a map. My jBuilder and Rails controller combination is not producing correctly formatted json for putting on a web map. Here's the relevant code.
overview_data.json.builder
json.type "FeatureCollection"
json.features #segments do |street|
if (street.extent_json) # only if item has a line drawn
json.type "Feature"
json.properties do
json.title "Was #{street.prevName} before #{street.dateEarliest} and now is #{street.currentName} #{street.dateLatest})"
end
json.geometry do
# json.type "LineString"
json.coordinates street.extent_json
end # json.geometry
end # if
end # json.features
overview_controller.rb
class OverviewController < ApplicationController
def index
end
def overview_data
#segments = Street.all
end
end
street.extent_json as it appears in a web form and in the database (Postgres via pgAdmin)
{"type":"LineString",
"coordinates":[[-118.25712423772116,34.01007010760971],
[-118.25649456380442,34.01016443793837],
[-118.25584971702219,34.01016443793837],
[-118.25427932544667,34.0102021700405],
[-118.25213995141625,34.010227324765935]]}
Output as seen in http://localhost:3000/overview/overview_data.json. At present there are about ten items that have extent_json. Below are the first few:
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"title": "Was 10th St. before 1903 and now is part of E. 9th Place (21). 1908)"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.24982816353442,34.035546195508864],[-118.25104052200915,34.03663976724366]]}"
}
},
{
"type": "Feature",
"properties": {
"title": "Was 37th St before 1903 and now is part of E. 40th Place 1928)"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.25712423772116,34.01007010760971],[-118.25649456380442,34.01016443793837],[-118.25584971702219,34.01016443793837],[-118.25427932544667,34.0102021700405],[-118.25213995141625,34.010227324765935]]}"
}
},
{
"type": "Feature",
"properties": {
"title": "Was Brook before 1903 and now is part of S. Toluca St. (26). and second block south gone 1908)"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.25862396508458,34.06087254304104],[-118.25933206826451,34.05994816216629]]}"
}
},
{
"type": "Feature",
"properties": {
"title": "Was Auto Pl before 1928 and now is Commonwealth Pl and a portion abandoned 1930)"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.28558737412096,34.07543021182353],[-118.28369373455645,34.07646106299854]]}"
}
},
{
"type": "Feature",
"properties": {
"title": "Was 3rd St before 1921 and now is Miramar St. One block abandoned )"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.26117539280003,34.05901974362122],[-118.2593849946753,34.05823410691563],[-118.25815599257271,34.05768101430694],[-118.25759459655055,34.05717191451128],[-118.25663111959356,34.05654339202722]]}"
}
},
{
"type": "Feature",
"properties": {
"title": "Was Gregory Way before and now is Gregory Way 2017)"
},
"geometry": {
"coordinates": "{\"type\":\"LineString\",\"coordinates\":[[-118.37295765057208,34.06188579510917],[-118.37272698059681,34.06172580874592],[-118.37264114990832,34.06161026285129],[-118.3725660480559,34.06146805230318],[-118.37253386154772,34.061414723286084],[-118.37249631062151,34.06118363049104]]}"
}
},
The problem is the added "{\"type\":\"LineString\",\"coordinates\" and closing }". Otherwise I think it's OK.
In the jBuilder I originally had json.type "LineString" in the json.geometry do loop and it's even worse adding: "geometry":{"type":"LineString","coordinates":"{\"type\":\"LineString\",\"coordinates\".
As Зелёный pointed out json.coordinates JSON.parse(street.extent_json) replacing similar line was needed. As he also pointed out I must have had some malformed json inputs which I did. Once that was cleaned up everything is working.
He also pointed out "in jbuilder template all things must be in plain Ruby, but you pass a json string(which comes from database) as result Rails tried to convert json string to json again."
But output still has an error, here's the first item:
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"title": "Was 10th St. before 1903 and now is part of E. 9th Place (21). 1908)"
},
"geometry": {
"coordinates": {
"type": "LineString",
"coordinates": [
[
-118.24982816353442,
34.035546195508864
],
[
-118.25104052200915,
34.03663976724366
]
]
}
}
},
An extra {
"coordinates": after geometry.
The problem is in extent_json method, it returns an object as json string. To resolve your issue, avoid the double call to_json.
To restate the problem: take a series of GeoJSONs from a database and use jBuilder to compile all the items that meet a certain criteria into a GeoJSON (for use in a Mapbox/Leaflet web map). https://stackoverflow.com/users/2057388/Зелёный provided the answer offline, but I want to document it to make sure I understand it and help anyone else with a similar problem. It helps to consider the jsons as hashes and that jbuilder is making another hash.
The input has two keys: type and coordinates.
The output has keys of type, properties, and geometry.
The properties value is a key title;
the geometry values are two keys type and coordinates. So overview_data.json.builder becomes:
extent = JSON.parse(street.extent_json) # the GeoJSON
json.type "Feature"
json.properties do
json.title h("Was #{street.prevName} before #{street.dateEarliest} and now is #{street.currentName} #{street.dateLatest}.")
end
json.geometry do
json.type "LineString"
json.coordinates extent["coordinates"]
end
Looks straightforward once it's laid out. Except for other key points. One was parsing extent_json to convert the string to a hash object. Then coordinates are extracted from that hash to put into the output json.

parse string from webAPI into multiple variables for openlayers GeoJSON

currently my webAPI method returns to me a long string for a GeoJSON layer that i need to parse through and separate out into mutliple variables that allows for me to create my necessary GeoJSON layer. Can i accomplish this easily through the str.split function or is a there another route that i need to take
The returned string from the webAPI looks like this:
{"type":"FeatureCollection","bbox":[1108864.9370570681,507099.9482870581,1109064.5346246646,507455.89728260477],"features":[{"type":"Feature","geometry":{"type":"Polygon","coordinates":[[[1109035.4443840273,507308.60334444791],[1108893.4509952962,507307.23951566964],[1108893.1628068388,507337.23816090077],[1109035.1562700756,507338.60198967904],[1109035.4443840273,507308.60334444791]]]},"properties":{"twp":"01","map_num":"8.0","sec":"33.00","qtr_sec":"003","map_block":"007","parcel":"008.00","pid":"018.033.00003007008.00","gis_acres":"0.0977962","debbie_ac":"0.10c","misc":"","scan_deeds":"T:\\Images\\Hyperlinked_Deeds\\00203","latitude":"37.2227488237","longitude":"-89.5082666075","name":"O'RILEY PROPERTIES LLC","site_addre":"519 MADISON ST","shape_leng":"344.000009295","shape_area":"4260.00340015","card_ac":"0.00c 0.00d","date":"1/1/0001 12:00:00 AM","ParcelId":"203","ParcelNumber":"0180330000300700800","_hg_layer":"PARCELS"}}
The features section of the string has an array of features but for use in this example i only copied of one specific feature that. the format I'm looking to set this up in is as follows:
var geojsonObject = {
'type': 'FeatureCollection',
'crs': {
'type': 'name',
'properties': {
//'name': 'EPSG:3857'
}
},
'features': [
{
"type": "Feature", "geometry":
{
"type": "Polygon", "coordinates": [[[1109035.4443840273, 507308.60334444791],
[1108893.4509952962, 507307.23951566964],
[1108893.1628068388, 507337.23816090077],
[1109035.1562700756, 507338.60198967904],
[1109035.4443840273, 507308.60334444791]]]
, "properties": {
"twp": "01",
"map_num": "8.0",
"sec": "33.00",
"qtr_sec": "003",
"map_block": "007",
"parcel": "008.00",
"pid": "018.033.00003007008.00",
"gis_acres": "0.0977962",
"debbie_ac": "0.10c",
"misc": "",
"scan_deeds": "T:\\Images\\Hyperlinked_Deeds\\00203",
"latitude": "37.2227488237",
"longitude": "-89.5082666075",
"name": "O'RILEY PROPERTIES LLC",
"site_addre": "519 MADISON ST",
"shape_leng": "344.000009295",
"shape_area": "4260.00340015",
"card_ac": "0.00c 0.00d",
"date": "1/1/0001 12:00:00 AM",
"ParcelId": "203",
"ParcelNumber": "0180330000300700800",
"_hg_layer": "PARCELS"
}
}
}
Again the features section of this code in my example just shows one specific feature but i will actually have several features that i need to display.
is parsing through this long string the easiest route to go or do i need to restructure the string that my WebAPI actually sends back to me

GeoJSON - Display all features in a table

I am trying to list all my features from a GeoJSON file in a table on a website and i am stuck figuring out how to achieve this.
As a first step i built a Leaflet map showing all locations loaded from the GeoJSON file which works pretty good.
What i would like to have in addition to the map is a rating system on a second page, which features all the locations from the GeoJSON in a table (I only need names for now, the rating system would be a different problem...).
Note that i am an absolute beginner and need a very detailed "tutorial" for this.
My GeoJSON looks like this:
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [ x,y ]
},
"properties": {
"FID":0,
"Shape *":"Point",
"Name":"XXX",
"Ditrict":"Dist1",
"Str_No":"Street 1",
"ZIP":"Some ZIP",
"Phone":"Some Number",
"Rating":4.5
}
},
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [ x,y ]
}, and so on
I hope that there is a simple solution for this.
Thank you in advance!
If your GeoJSON object is var geoJSON, you can get all the names for each feature by doing the following:
var featureNames = [];
for (var i = 0; i < geoJSON.features.length; i++) {
var currentFeature = geoJSON.features[i];
var featureName = currentFeature.properties.Name;
var featureId = currentFeature.properties.FID;
console.log(featureName);
featureNames.push({ featureId: featureId, featureName : featureName });
}
So featureNames will have each feature object with it's name in an array.
To put them all in a table, I'm going to use jQuery DataTables. If I have a <div id="myTable">, then:
$('#myTable').DataTable( {
"columnDefs": [
{ "title": "Feature Names", "targets": 0 }
]
data: featureNames,
scrollY: 300,
paging: false
} );

Adding GeometryCollections with Mongoose

I've build a form in Angular to add GeoJSON features to MongoDB using Mongoose. The features include several properties and a GeometryCollection with a point and a lineString.
Here comes the trouble: I was able to create features with just a single point in my geometry but I'm unable to create features with a geometry collection that uses a lineString. I get either:
16755 Can't extract geo keys from object, malformed geometry?
or:
{ [CastError: Cast to number failed for value "0,0,1,1" at path "coordinates"]
message: 'Cast to number failed for value "0,0,1,1" at path "coordinates"',
name: 'CastError',
type: 'number',
value: [[0,0],[1,1]],
path: 'coordinates' }'
I do realize it says type: 'number' while my schema is set to an array of arrays:
var featureSchema = new mongoose.Schema({
'type': {
type: String,
default: "Feature"
},
geometry: {
'type': {
type: String,
default: 'GeometryCollection',
}, geometries: [{
'type': {
type: String,
default: 'Point'
},
coordinates: [Number]
}, {
'type': {
type: String,
default: 'LineString'
},
coordinates: {
type: [Array],
default: [[0,0], [1,1]]
}
}]
},
properties: {
title: String
}
});
So my first question is: does anyone know how to properly add features using GeometryCollections with Mongoose?
My second question is how to add an array of arrays when using forms? When I use a text input now I get my array of arrays delivered as a string. I was able to convert the point coordinates using:
var array = req.body.feature.geometry.geometries.coordinates.split(',');
for(var i=0; i<array.length; i++) {
array[i] = +array[i];
}
Is there a way to convert a string (ie "[ [0,0], [1,1] ]") to an array of arrays to create the lineString coordinates?
Thanks in advance!
The proper way is to split this into multiple schemas, which is much easier to read, use and maintain. For example:
GeoJSON.FeatureCollection = {
"type" : {
"type": String,
"default": "FeatureCollection"
},
"features": [GeoJSON.Feature]
}
GeoJSON.Feature = {
"id": {
"type": "String"
},
"type": {
"type": String,
"default": "Feature"
},
"properties": {
"type": "Object"
},
"geometry": GeoJSON.Geometry
}
GeoJSON.GeometryCollection = {
"type": {
"type": String,
"default": "GeometryCollection"
},
"geometries": [GeoJSON.Geometry]
}
GeoJSON.Geometry = {
"type": {
"type": String,
"enum": [
"Point",
"MultiPoint",
"LineString",
"MultiLineString",
"Polygon",
"MultiPolygon"
]
},
"coordinates": []
}
Taken from: https://github.com/RideAmigosCorp/mongoose-geojson-schema

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