合并R中的多个JSON文件

Question

I am currently trying to merge multiple (380) JSON files into one dataframe.

I came up with the following code, which I think should work. But unfortunately I still keep getting errors.

 library(jsonlite)
 multmerge <- function(mypath)
{filenames=list.files(path=mypath, full.names=TRUE) 
 datalist = lapply(filenames, function(x){fromJSON(file=x)})
 Reduce(function(x,y) {merge(x,y)}, datalist)}

mymergeddata <- multmerge("~/Scriptie/LaLiga")

Error in fromJSON(file = x) : argument "txt" is missing, with no default

Is there somebody who knows whats wrong with it?

"@attributes": { "id": 771041269, "event_id": 494, "type_id": "1", "period_id": "2", "min": 57, "sec": 4, "player_id": "17861", "team_id": "186", "outcome": "1", "x": 27.5, "y": 71.8, "assist": "0", "keypass": "0", "timestamp": "2015-09-12T16:09:58.000", "TimeStamp": { "locale": "2015-09-12T16:14:58.000Z", "utc": "2015-09-12T14:14:58.000Z" }, "version": { "lo": 1325465600, "hi": 1605574594 } }, "Q": [ { "@attributes": { "id": 1051565894, "qualifier_id": "141", "value": "45.1" } }, { "@attributes": { "id": 1903370784, "qualifier_id": "140", "value": "12.8" } }, { "@attributes": { "id": 1828708519, "qualifier_id": "212", "value": "23.8" } }, { "@attributes": { "id": 1347694276, "qualifier_id": "5", "value": "" } }, { "@attributes": { "id": 1265264016, "qualifier_id": "56", "value": "Back" } }, { "@attributes": { "id": 1627212783, "qualifier_id": "152", "value": "" } }, { "@attributes": { "id": 1369689442, "qualifier_id": "213", "value": "4.0" } } ] },

Answer 1

Let nl.json be your input file. I tweaked as follows the json (removing the "@" and including bracket in the beginning and end of the file cf. attached)

      {"attributes": {
                        "id": 771041269,
                        "event_id": 494,
                        "type_id": "1",
                        "period_id": "2",
                        "min": 57,
                        "sec": 4,
                        "player_id": "17861",
                        "team_id": "186",
                        "outcome": "1",
                        "x": 27.5,
                        "y": 71.8,
                        "assist": "0",
                        "keypass": "0",
                        "timestamp": "2015-09-12T16:09:58.000",
                        "TimeStamp": {
                            "locale": "2015-09-12T16:14:58.000Z",
                            "utc": "2015-09-12T14:14:58.000Z"
                        },
                        "version": {
                            "lo": 1325465600,
                            "hi": 1605574594
                        }
                    },
                    "Q": [
                        {
                            "@attributes": {
                                "id": 1051565894,
                                "qualifier_id": "141",
                                "value": "45.1"
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1903370784,
                                "qualifier_id": "140",
                                "value": "12.8"
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1828708519,
                                "qualifier_id": "212",
                                "value": "23.8"
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1347694276,
                                "qualifier_id": "5",
                                "value": ""
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1265264016,
                                "qualifier_id": "56",
                                "value": "Back"
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1627212783,
                                "qualifier_id": "152",
                                "value": ""
                            }
                        },
                        {
                            "@attributes": {
                                "id": 1369689442,
                                "qualifier_id": "213",
                                "value": "4.0"
                            }
                        }
                    ]
                }
        }

I also changed the rjson::fromJSON(file="nl.json",method = "R") yielding in

$attributes
$attributes$id
[1] 771041269

$attributes$event_id
[1] 494

$attributes$type_id
[1] "1"

$attributes$period_id
[1] "2"

$attributes$min
[1] 57

$attributes$sec
[1] 4

$attributes$player_id
[1] "17861"

$attributes$team_id
[1] "186"

$attributes$outcome
[1] "1"

$attributes$x
[1] 27.5

$attributes$y
[1] 71.8

$attributes$assist
[1] "0"

$attributes$keypass
[1] "0"

$attributes$timestamp
[1] "2015-09-12T16:09:58.000"

$attributes$TimeStamp
$attributes$TimeStamp$locale
[1] "2015-09-12T16:14:58.000Z"

$attributes$TimeStamp$utc
[1] "2015-09-12T14:14:58.000Z"


$attributes$version
$attributes$version$lo
[1] 1325465600

$attributes$version$hi
[1] 1605574594



$Q
$Q[[1]]
$Q[[1]]$`@attributes`
$Q[[1]]$`@attributes`$id
[1] 1051565894

$Q[[1]]$`@attributes`$qualifier_id
[1] "141"

$Q[[1]]$`@attributes`$value
[1] "45.1"



$Q[[2]]
$Q[[2]]$`@attributes`
$Q[[2]]$`@attributes`$id
[1] 1903370784

$Q[[2]]$`@attributes`$qualifier_id
[1] "140"

$Q[[2]]$`@attributes`$value
[1] "12.8"



$Q[[3]]
$Q[[3]]$`@attributes`
$Q[[3]]$`@attributes`$id
[1] 1828708519

$Q[[3]]$`@attributes`$qualifier_id
[1] "212"

$Q[[3]]$`@attributes`$value
[1] "23.8"



$Q[[4]]
$Q[[4]]$`@attributes`
$Q[[4]]$`@attributes`$id
[1] 1347694276

$Q[[4]]$`@attributes`$qualifier_id
[1] "5"

$Q[[4]]$`@attributes`$value
[1] ""



$Q[[5]]
$Q[[5]]$`@attributes`
$Q[[5]]$`@attributes`$id
[1] 1265264016

$Q[[5]]$`@attributes`$qualifier_id
[1] "56"

$Q[[5]]$`@attributes`$value
[1] "Back"



$Q[[6]]
$Q[[6]]$`@attributes`
$Q[[6]]$`@attributes`$id
[1] 1627212783

$Q[[6]]$`@attributes`$qualifier_id
[1] "152"

$Q[[6]]$`@attributes`$value
[1] ""



$Q[[7]]
$Q[[7]]$`@attributes`
$Q[[7]]$`@attributes`$id
[1] 1369689442

$Q[[7]]$`@attributes`$qualifier_id
[1] "213"

$Q[[7]]$`@attributes`$value
[1] "4.0"

Answer 2

Given a function decode_json that reads your specific JSON data into a data frame, you can efficiently combine the decoding of multiple files into one final data frame as follows:

import_json_files <- function(files) {
  all <- lapply(files, fromJSON)
  dec <- lapply(all, decode_json)
  bind_rows(dec)
}