将数据转换为包含所有对象的 Json

Question

我想将功能文件转换为 json，以便我可以将其传递给 RMD 文件中的 javascript 函数。

然而，toJSON 函数似乎将其展平并删除了许多字段和结构，如下所示。我如何转换它并使其保持完整，就像我使用 sf::st_write?

写入文件一样

url <- 'https://opendata.arcgis.com/api/v3/datasets/bf9d32b1aa9941af84e6c2bf0c54b1bb_0/downloads/data?format=geojson&spatialRefId=4326'
ukWardShapes <- sf::st_read(url) %>% 
  head(2)

# Looks OK when written out
sf::st_write(ukWardShapes, "wardShapes.geojson")

# Converting to json with toJSON seems drop other top level fields (type, name, crs) and list the objects within features object, 
# but without type, and puts all fields in properties at the top level of object.

json_data <- jsonlite::toJSON(ukWardShapes)

# I want to do this as I need to pass it to javascript within an RMD like this
htmltools::tags$script(paste0("var ukWardShapes = ", json_data, ";"))

# Output from st_write - with all the objects and fields listed properly
{
  "type": "FeatureCollection",
  "name": "wardShapes",
  "crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:OGC:1.3:CRS84" } },
  "features": [
    { "type": "Feature", "properties": { "OBJECTID": 1, "WD21CD": "E05000026", "WD21NM": "Abbey", "WD21NMW": " ", "BNG_E": 544433, "BNG_N": 184376, "LONG": 0.081276, "LAT": 51.53981, "SHAPE_Length": 0.071473941285613768, "SHAPE_Area": 0.00015225110241064838 }, "geometry": { "type": "MultiPolygon", "coordinates": [ [ [ [ 0.093628520000038, 51.53767283600007 ], [ 0.08163128800004, 51.539165094000055 ], [ 0.085507102000065, 51.537043160000053 ], [ 0.075954208000041, 51.533595714000057 ], [ 0.07333983500007, 51.537621201000036 ], [ 0.068771363000053, 51.536206993000064 ], [ 0.068303699000069, 51.544253423000043 ], [ 0.068361695000021, 51.544390390000046 ], [ 0.08006389600007, 51.544772356000067 ], [ 0.093628520000038, 51.53767283600007 ] ] ] ] } },
    { "type": "Feature", "properties": { "OBJECTID": 2, "WD21CD": "E05000027", "WD21NM": "Alibon", "WD21NMW": " ", "BNG_E": 549247, "BNG_N": 185196, "LONG": 0.150987, "LAT": 51.545921, "SHAPE_Length": 0.074652046036690151, "SHAPE_Area": 0.00017418950412786572 }, "geometry": { "type": "MultiPolygon", "coordinates": [ [ [ [ 0.161601914000073, 51.543327754000074 ], [ 0.147931795000034, 51.541598449000048 ], [ 0.140256898000075, 51.54111542000004 ], [ 0.13420572800004, 51.540716652000071 ], [ 0.131925236000029, 51.543763455000033 ], [ 0.14633003900002, 51.546332889000041 ], [ 0.142816723000067, 51.550973604000035 ], [ 0.156378253000071, 51.551020271000027 ], [ 0.161601914000073, 51.543327754000074 ] ] ] ] } }
  ]
}

# Output from toJson which seems to have a lot of structure removed. Note, I'm not
# concerned about it being pretty and separated into lines
[{
  "OBJECTID":1, "WD21CD":"E05000026", "WD21NM":"Abbey", "WD21NMW":" ", "BNG_E":544433, "BNG_N":184376, "LONG":0.0813, "LAT":51.5398, "SHAPE_Length":0.0715, "SHAPE_Area":0.0002, "geometry":{
    "type":"MultiPolygon", "coordinates":[[[[0.0936, 51.5377], [0.0816, 51.5392], [0.0855, 51.537], [0.076, 51.5336], [0.0733, 51.5376], [0.0688, 51.5362], [0.0683, 51.5443], [0.0684, 51.5444], [0.0801, 51.5448], [0.0936, 51.5377]]]]
  }
}, {
  "OBJECTID":2, "WD21CD":"E05000027", "WD21NM":"Alibon", "WD21NMW":" ", "BNG_E":549247, "BNG_N":185196, "LONG":0.151, "LAT":51.5459, "SHAPE_Length":0.0747, "SHAPE_Area":0.0002, "geometry":{
    "type":"MultiPolygon", "coordinates":[[[[0.1616, 51.5433], [0.1479, 51.5416], [0.1403, 51.5411], [0.1342, 51.5407], [0.1319, 51.5438], [0.1463, 51.5463], [0.1428, 51.551], [0.1564, 51.551], [0.1616, 51.5433]]]]
  }
}]

Answer 1

根据上面@SymbolixAU 的评论，答案是使用

geojsonsf::sf_geojson() 而不是 jsonlite::toJSON()，因为 geojson 是 JSON 空间数据的特定结构，它需要特定的解析器。

所以我的代码行应该是：

json_data <- geojsonsf::sf_geojson(ukWardShapes)

将数据转换为包含所有对象的 Json

Convert data to Json with all objects included

json

r

jsonlite

sf