Display TLV Formats in Object Tree

[oliver-om]

According to the Kaitai Struct documentation, the idiomatic way to implement Type-Length-Value formats is to use type: switch-on to select the body format for each record (https://doc.kaitai.io/user_guide.html#tlv).

This definitely produces cleaner .ksy files, but the Web IDE does not appear to parse the contents of the record body -- it just shows up as a raw byte array in the Object Tree. This means you cannot debug the contents/parsing of each record type.

In order to see the parsed contents of each record type, you need to replace the switch-on approach with the the (discouraged) approach of conditionally including all possible record types separately.

Switch-on	Conditional Include
body is shown as a raw byte array in the Object Tree	body_1 or body_2 is parsed and displayed correctly in the Object Tree

For example, this is how the example PNG file is displayed:

[generalmimon]

@oliver-om:

For example, this is how the example PNG file is displayed

It works as expected, because the IDAT and IEND chunks are not specifically processed in type/cases, so they fallback to being treated as raw byte arrays:

image/png.ksy:64-73

      - id: body
        size: len
        type:
          switch-on: type
          cases:
            # Critical chunks
            # '"IHDR"': ihdr_chunk
            '"PLTE"': plte_chunk
            # IDAT = raw
            # IEND = empty, thus raw

In order to see the parsed contents of each record type, you need to replace the switch-on approach with the the (discouraged) approach of conditionally including all possible record types separately.

No. Try for example some animated PNGs (APNGs) from https://philip.html5.org/tests/apng/tests.html on this PNG spec - they should have some chunks whose contents are described by the .ksy, so you'll see their inner details.