JSON Object#

group json_object

Functions

std::unique_ptr<cudf::column> get_json_object(cudf::strings_column_view const &col, cudf::string_scalar const &json_path, get_json_object_options options = get_json_object_options{}, rmm::cuda_stream_view stream = cudf::get_default_stream(), rmm::device_async_resource_ref mr = rmm::mr::get_current_device_resource())#

Apply a JSONPath string to all rows in an input strings column.

Applies a JSONPath string to an incoming strings column where each row in the column is a valid json string. The output is returned by row as a strings column.

https://tools.ietf.org/id/draft-goessner-dispatch-jsonpath-00.html Implements only the operators: $ . [] *

Throws:

std::invalid_argument – if provided an invalid operator or an empty name

Parameters:

  • col – The input strings column. Each row must contain a valid json string

  • json_path – The JSONPath string to be applied to each row

  • options – Options for controlling the behavior of the function

  • stream – CUDA stream used for device memory operations and kernel launches

  • mr – Resource for allocating device memory

Returns:

New strings column containing the retrieved json object strings

class get_json_object_options#
#include <json.hpp>

Settings for get_json_object().

Public Functions

explicit get_json_object_options() = default#

Default constructor.

inline bool get_allow_single_quotes() const#

Returns true/false depending on whether single-quotes for representing strings are allowed.

Returns:

true if single-quotes are allowed, false otherwise.

inline bool get_strip_quotes_from_single_strings() const#

Returns true/false depending on whether individually returned string values have their quotes stripped.

When set to true, if the return value for a given row is an individual string (not an object, or an array of strings), strip the quotes from the string and return only the contents of the string itself. Example:

With strip_quotes_from_single_strings OFF:
Input  = {"a" : "b"}
Query  = $.a
Output = "b"

With strip_quotes_from_single_strings ON:
Input  = {"a" : "b"}
Query  = $.a
Output = b
Returns:

true if individually returned string values have their quotes stripped.

inline bool get_missing_fields_as_nulls() const#

Whether a field not contained by an object is to be interpreted as null.

When set to true, if an object is queried for a field it does not contain, a null is returned.

With missing_fields_as_nulls OFF:
Input  = {"a" : [{"x": "1", "y": "2"}, {"x": "3"}]}
Query  = $.a[*].y
Output = ["2"]

With missing_fields_as_nulls ON:
Input  = {"a" : [{"x": "1", "y": "2"}, {"x": "3"}]}
Query  = $.a[*].y
Output = ["2", null]
Returns:

true if missing fields are interpreted as null.

inline void set_allow_single_quotes(bool _allow_single_quotes)#

Set whether single-quotes for strings are allowed.

Parameters:

_allow_single_quotes – bool indicating desired behavior.

inline void set_strip_quotes_from_single_strings(bool _strip_quotes_from_single_strings)#

Set whether individually returned string values have their quotes stripped.

Parameters:

_strip_quotes_from_single_strings – bool indicating desired behavior.

inline void set_missing_fields_as_nulls(bool _missing_fields_as_nulls)#

Set whether missing fields are interpreted as null.

Parameters:

_missing_fields_as_nulls – bool indicating desired behavior.

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