для объединения используйте:
var object = [{
osmstartnode: 370705004,
osmendnode: 1369956654,
congestion_level: 1
},
{
osmstartnode: 42469049,
osmendnode: 42469053,
congestion_level: 2
}
];
в свойствах:
var roadobjt = [{
"type": "Feature",
"geometry": {
"type": "LineString",
"coordinates": [
[-74.0048445, 40.7124759],
[-74.0048533, 40.71245],
[-74.0048604, 40.7124243],
[-74.0048578, 40.7123974],
[-74.0048468, 40.7123722],
[-74.0048252, 40.7123472],
[-74.0045725, 40.7121422]
]
},
properties: {
"osmhighway": "motorway_link",
"osmoneway": "yes",
"osmwayid": 5669636,
"osmstartnode": 370705004,
"osmendnode": 1369956654,
"speed_mean_mph": 16,
"pct_from_freeflow": 72,
"speed_freeflow_mph": 22
}
},
{
"type": "Feature",
"geometry": {
"type": "LineString",
"coordinates": [
[-73.99866284812883, 40.59729307801823],
[-73.99879364640618, 40.59716957964474],
[-73.99913817998096, 40.596844447960684],
[-73.99931411513008, 40.596676614430145]
]
},
properties: {
"osmname": "Bay Parkway",
"osmhighway": "primary",
"osmoneway": "no",
"osmwayid": 5675398,
"osmstartnode": 42469049,
"osmendnode": 42469053,
"speed_mean_mph": 20,
"pct_from_freeflow": 67,
"speed_freeflow_mph": 29
}
}
];
используйте:
roadobjt.map((r, i) => { r.properties = Object.assign(r.properties, object[i]); return r;})
результаты:
[{"type":"Feature","geometry":{"type":"LineString","coordinates":[[-74.0048445,40.7124759],[-74.0048533,40.71245],[-74.0048604,40.7124243],[-74.0048578,40.7123974],[-74.0048468,40.7123722],[-74.0048252,40.7123472],[-74.0045725,40.7121422]]},"properties":{"osmhighway":"motorway_link","osmoneway":"yes","osmwayid":5669636,"osmstartnode":370705004,"osmendnode":1369956654,"speed_mean_mph":16,"pct_from_freeflow":72,"speed_freeflow_mph":22,"congestion_level":1}},{"type":"Feature","geometry":{"type":"LineString","coordinates":[[-73.99866284812883,40.59729307801823],[-73.99879364640618,40.59716957964474],[-73.99913817998096,40.596844447960684],[-73.99931411513008,40.596676614430145]]},"properties":{"osmname":"Bay Parkway","osmhighway":"primary","osmoneway":"no","osmwayid":5675398,"osmstartnode":42469049,"osmendnode":42469053,"speed_mean_mph":20,"pct_from_freeflow":67,"speed_freeflow_mph":29,"congestion_level":2}}]