JSON Lines text format (JSONL) [1] is a line-delimited JSON format where
objects are separated by the new line character (\n, LF) as opposed to
the JSON Sequence text format (json-seq) where JSON text is encapsulated
in an ASCII Record Separator (0x1E, RS) and ASCII Line Feed character
(0x0A, LF).
Whilst JSONL is also used for data streaming, this simpler format is
better suited for logging and works also well with traditional
line-oriented Unix tooling (e.g. grep or sed).
Add this format to util_fmt so that users have more choice and control
over formats that are required for their usecases.
Add helper functions that let the user determine whether a given format
type is JSON in general or a JSON streaming format (such as json-seq or
jsonl).
For better readability and more clarity use the helper function
util_fmt_is_json_stream() where the same decision is made for both
JSON streaming formats FMT_JSONSEQ and FMT_JSONL.
[1] https://jsonlines.org/
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Add helper functions for converting structured key-value data into
different formats such as JSON, text pairs, and CSV.
Using these functions the resulting output format can be dynamically
configured at run-time without the need to duplicate output-generating
code for each format type. Also format-specific requirements such as
quoting, indentation, and comma-placement are automatically taken care
of.
Basic API calling sequence:
util_fmt_init() => Select output format
util_fmt_obj_start() => Start a new object or list
util_fmt_pair() => Emit a key-value pair
util_fmt_obj_end() => End the most recent object or list
util_fmt_exit() => Cleanup
Notes:
- Supported data elements are objects, lists and key-value pairs
(mappings)
- Scalars are only supported as part of a mapping
Reviewed-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
