A fairly opinionated tool that provides the output of commands that typically need post-processing with sed, grep as structured data. Inspired loosely by Powershell and Nushell, and generally by the idea that stringly-typed data can make life harder than it needs to be.

Provides output as ndjson ("Newline-delimited JSON"), which is also known as the json-lines format.

Just a prototype at this stage. Seeking feedback.

Generally speaking, you either pipe the output of the intended command (with the necessary arguments to enable parsing by machine) and provide the source prefixed with a double-dash, or provide the command's name as the first argument.

For example, consider lspci. The following two forms produce equivalent output:

data-from lspci
lspci -vmm -nn | data-from --lspci

Note: Failing to provide the information in the intended way will cause data-from to fail. For example, omitting the -vmm -nn flags from lspci means that data-from won't be able to parse the output correctly.

When you provide a command's name, rather than sending data to stdin, data-from will invoke the command on its own within a sub-process.

To list PCI interfaces, you can either request that data-from invokes lspci itself (data-from lspci), or you can pipe data into data-from (lspci -vmm -nn | data-from --lspci).

Example output (with some formatting applied):

$ data-from lspci
...
{
  "slot": "6c:00.0",
  "device": "RTS5260 PCI Express Card Reader",
  "device-code": { "hex": ["52", "60"], "int": [82, 96] },
  "sub-device": "RTS5260 PCI Express Card Reader",
  "sub-device-code": { "hex": ["09", "7d"], "int": [9, 125] },
  "class":"Unassigned class",
  "class-code": { "hex": ["ff", "00"], "int": [255, 0] },
  "vendor":"Realtek Semiconductor Co., Ltd.",
  "vendor-code": { "hex": ["10", "ec"], "int": [16, 236] },
  "sub-vendor": "Dell",
  "sub-vendor-code": { "hex": ["10", "28"], "int": [16, 40] },
  "revision": 1,
  "programming-interface": null
}

The *-code values are the numbers supplied by the devices themselves. To match these codes to names, your computer typically makes a lookup to the PCI ID Repository.

• "grep and hope"
• jc is a Python tool which is much more complete. It requires a Python interpreter and only produces JSON. The JSON output is typically wrapped in an array, which makes it difficult for follow-on tools which expect input line-by-line.