Manipulate GeoJSON/JSON with jq

README.md

Manipulate (Geo)JSON with jq

Remove attributes with jq from a GeoJSON file:

cat points.geojson | jq ".features[].properties |= del(.c) | .features[].properties |= del(.d)"

Add property with default value:

cat points.geojson | jq ".features[].properties.z = true"

Add nested property with default values:

cat points.geojson | jq '.features[].properties.nested2 = {"q": "1","r": "2"}'

Unstringify stringified JSON:

cat points.geojson | jq '.features[].properties.nestedstring |= fromjson' 

Stringify property:

cat points.geojson | jq '.features[].properties.nested |= tostring' 

Rename property:

cat points.geojson | jq '.features[].properties |= with_entries(if .key == "d" then .key = "e" else . end)'

Add property with random value (calling different program):

#!/usr/bin/env bash
set -euo pipefail

function propValFunction(){
    shuf -n1  /usr/share/dict/dutch | xargs -0 echo -n
}

function addPropNameGeoJSON(){
    geojson_file="$1"
    prop_name="$2"
    prop_function="$3"
    count=0
    jq -c '.features[]' < "$geojson_file" |
    while IFS=$"\n" read -r c; do
        prop_val=$($prop_function) 
        jq  ".features[$count].properties.$prop_name = \"${prop_val}\"" < "$geojson_file" | sponge "$geojson_file"
        count=$(bc<<<"$count+1")
    done
}

GEOJSON_FILE="points.geojson"
PROP_NAME="label"

addPropNameGeoJSON $GEOJSON_FILE $PROP_NAME propValFunction

Convert JSON to GeoJSON:

JSON_STRING='{"locations": [{"lon": 151.079209240775, "lat": -33.8510778634911, "time": 1535260212.13903}, {"lon": 151.075161398092, "lat": -33.8468726325816, "time": 1535261260.22272}, {"lon": 151.074015443979, "lat": -33.8385713830357, "time": 1535261877.66436}]}'
JQ_QUERY='{"type": "FeatureCollection","name": "points","features":[.locations[] | {"type":"Feature","properties":{"time":.time},"geometry":{"type":"Point","coordinates":[.lon,.lat]}}]}'
echo $JSON_STRING  | jq  $JQ_QUERY

Query GeoJSON

Get first x features:

jq '.features = .features[:10]' < $GEOJSON_FILE

Get features with property url that satisfy regex:

jq '.features = [.features[] | select(.properties.url | test("M_01CZ2.tif|M_01HZ1.tif|M_01CZ1.tif|M_01DZ2.tif|M_01GN1.tif|M_01GZ2.tif|M_01GZ1.tif|M_01DZ1.tif|M_01GN2.tif|M_01HN1.tif"))]' < $GEOJSON_FILE

points.geojson

{
  "type": "FeatureCollection",
  "name": "points",
  "crs": {
    "type": "name",
    "properties": {
      "name": "urn:ogc:def:crs:OGC:1.3:CRS84"
    }
  },
  "features": [
    {
      "type": "Feature",
      "properties": {
        "a": "a",
        "b": "b",
        "c": "c",
        "d": "d",
        "nested": {
          "q": "1",
          "r": "2"
        },
        "nestedstring": "{\"q\":\"1\",\"r\":\"2\"}"
      },
      "geometry": {
        "type": "Point",
        "coordinates": [
          6.65493,
          28.690141
        ]
      }
    },
    {
      "type": "Feature",
      "properties": {
        "a": "e",
        "b": "f",
        "c": "g",
        "d": "h",
        "nested": {
          "q": "1",
          "r": "2"
        },
        "nestedstring": "{\"q\":\"1\",\"r\":\"2\"}"
      },
      "geometry": {
        "type": "Point",
        "coordinates": [
          3.105634,
          14.640845
        ]
      }
    },
    {
      "type": "Feature",
      "properties": {
        "a": "1",
        "b": "2",
        "c": "3",
        "d": "4",
        "nested": {
          "q": "1",
          "r": "2"
        },
        "nestedstring": "{\"q\":\"1\",\"r\":\"2\"}"
      },
      "geometry": {
        "type": "Point",
        "coordinates": [
          25.584507,
          27.47007
        ]
      }
    }
  ]
}