asdf

The asdf command-line tool is a companion utility installed alongside libasdf. It is a thin wrapper around the library offering a handful of sub-commands for inspecting ASDF files and extracting their data. Its capabilities are currently modest but will be expanded in future releases.

Each tool provided by asdf is run as a separate sub-command.

Synopsis

asdf COMMAND [ARGS...]

Run asdf COMMAND --help for detailed help on any sub-command. The available sub-commands are:

Command	Description
info	Print a rendering of an ASDF tree
dd	Dump data from an ASDF binary block
events	Print the event stream from the ASDF parser (for debugging)
verify-checksums	Verify binary block MD5 checksums

The global asdf command itself accepts -h / --help and --usage.

asdf info

Print a human-readable rendering of an ASDF file’s YAML tree, and optionally information about its binary blocks.

asdf info [OPTIONS] FILENAME

--no-tree

Do not show the tree.

-b, --blocks

Show information about the file’s binary blocks.

--verify-checksums

Verify the MD5 checksum of each block (implies -b).

For example, to print the tree of a file together with its block information:

asdf info --blocks observation.asdf

asdf dd

Dump the raw bytes of a single binary block to a file or to standard output, named either by block index or by the tree path of an ndarray that references it. Exactly one of --block or --ndarray must be given.

asdf dd [OPTIONS] INPUT [OUTPUT|-]

INPUT is the ASDF file to read. OUTPUT is the destination file; a single - writes the data to standard output.

-b N, --block N

Index of the block to extract (starting from 0).

-n PATH, --ndarray PATH

Tree path of an ndarray whose underlying block should be extracted.

-r, --raw

For a compressed block, dump the raw compressed bytes rather than decompressing them first. Has no effect on uncompressed blocks.

-c N, --chunk-size N

Read/write the data in chunks of N bytes.

--no-lazy-decompression

Disable lazy (page-fault-driven) decompression; decompress eagerly instead. Intended mainly for debugging.

For example, to extract the data of the ndarray at /data into a file:

asdf dd --ndarray data observation.asdf data.bin

asdf events

Print the low-level event stream produced by the ASDF parser as it walks a file. This is primarily a debugging aid for libasdf itself and exposes the event-based parsing API (see libasdf - The ASDF C Library).

asdf events [OPTIONS] FILENAME

-v, --verbose

Show extra information about each event.

--no-yaml

Do not produce YAML stream events (emit only the ASDF-structural events).

--cap-tree

Buffer the YAML tree and print it. This corresponds to the parser’s tree-buffering option and is mainly useful for debugging.

asdf verify-checksums

Verify the MD5 checksum recorded in each binary block header against the checksum computed from the block’s data. The exit status is non-zero if any block fails verification.

asdf verify-checksums [OPTIONS] FILENAME

-v, --verbose

Print the checksum of every block, whether or not it verifies. Without this option the command is quiet on success and reports only mismatches.

Note

Checksum verification requires that libasdf was built with MD5 support (via libbsd). Without it, blocks are always reported as valid.