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# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
#' Read a JSON file
#'
#' Using [JsonTableReader]
#'
#' @inheritParams read_delim_arrow
#' @param schema [Schema] that describes the table.
#' @param ... Additional options passed to `JsonTableReader$create()`
#'
#' @return A `data.frame`, or a Table if `as_data_frame = FALSE`.
#' @export
#' @examplesIf arrow_with_json()
#' tf <- tempfile()
#' on.exit(unlink(tf))
#' writeLines('
#' { "hello": 3.5, "world": false, "yo": "thing" }
#' { "hello": 3.25, "world": null }
#' { "hello": 0.0, "world": true, "yo": null }
#' ', tf, useBytes = TRUE)
#' df <- read_json_arrow(tf)
read_json_arrow <- function(file,
col_select = NULL,
as_data_frame = TRUE,
schema = NULL,
...) {
if (!inherits(file, "InputStream")) {
file <- make_readable_file(file)
on.exit(file$close())
}
tab <- JsonTableReader$create(file, schema = schema, ...)$Read()
col_select <- enquo(col_select)
if (!quo_is_null(col_select)) {
tab <- tab[vars_select(names(tab), !!col_select)]
}
if (isTRUE(as_data_frame)) {
tab <- as.data.frame(tab)
}
tab
}
#' @include arrow-package.R
#' @rdname CsvTableReader
#' @usage NULL
#' @format NULL
#' @docType class
#' @export
JsonTableReader <- R6Class("JsonTableReader",
inherit = ArrowObject,
public = list(
Read = function() json___TableReader__Read(self)
)
)
JsonTableReader$create <- function(file,
read_options = JsonReadOptions$create(),
parse_options = JsonParseOptions$create(schema = schema),
schema = NULL,
...) {
assert_is(file, "InputStream")
json___TableReader__Make(file, read_options, parse_options)
}
#' @rdname CsvReadOptions
#' @usage NULL
#' @format NULL
#' @docType class
#' @export
JsonReadOptions <- R6Class("JsonReadOptions", inherit = ArrowObject)
JsonReadOptions$create <- function(use_threads = option_use_threads(), block_size = 1048576L) {
json___ReadOptions__initialize(use_threads, block_size)
}
#' @rdname CsvReadOptions
#' @usage NULL
#' @format NULL
#' @docType class
#' @export
JsonParseOptions <- R6Class("JsonParseOptions", inherit = ArrowObject)
JsonParseOptions$create <- function(newlines_in_values = FALSE, schema = NULL) {
if (is.null(schema)) {
json___ParseOptions__initialize1(newlines_in_values)
} else {
json___ParseOptions__initialize2(newlines_in_values, schema)
}
}
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