Getting Started ​

Fx is a dual-purpose command-line tool tailored for JSON, providing both a terminal-based JSON viewer and a JSON processing utility. While the JSON viewer is crafted in Go and functions without external dependencies, the JSON processing tool is developed in JS, compatible with Node.js and Deno.

To use Fx:

cat data.json | fx

cat data.json | fx

Or directly:

fx data.json

fx data.json

JSON Processing ​

In fx, arguments are treated as JavaScript functions. Input data is passed sequentially through each provided function:

echo '{"name": "world"}' | fx 'x => x.name' 'x => `Hello, ${x}!`'

echo '{"name": "world"}' | fx 'x => x.name' 'x => `Hello, ${x}!`'

You can also utilize standard JavaScript functions:

echo '{"name": "world"}' | fx 'Object.keys'

echo '{"name": "world"}' | fx 'Object.keys'

Fx also introduces syntactical sugar to enhance simplicity:

• Reference input data using x or this.
• Start expressions with . to avoid repeating the x => x.

echo '{"name": "world"}' | fx .name '`Hello, ${x}!`'

echo '{"name": "world"}' | fx .name '`Hello, ${x}!`'

That's it. So simple!

Streaming Mode ​

Fx is designed to handle both line-delimited JSON and concatenated JSON streaming:

echo '{"text": "Hello"}' '{"text": "World!"}' | fx .text

echo '{"text": "Hello"}' '{"text": "World!"}' | fx .text

Output:

Hello
World!

Hello
World!

For collective processing of a JSON stream as a single array, use the --slurp or -s flag:

echo '{"text": "Hello"}' '{"text": "World!"}' | fx --slurp '.map(x => x.text)' '.join(", ")'

echo '{"text": "Hello"}' '{"text": "World!"}' | fx --slurp '.map(x => x.text)' '.join(", ")'

Output:

Hello, World!

Hello, World!

Interactive Mode ​

Fx provides an interactive mode that allows you to explore JSON interactively. To initiate the interactive mode, pipe a JSON into fx:

cat data.json | fx

cat data.json | fx

Or:

fx data.json

fx data.json

Easily navigate through your JSON using arrow or vim keys.

Dig ​

Press . to adjust the current path. Fx utilizes a fuzzy search. Press tab or . to opt for the current suggestion.

Searching ​

Start a search with /, inputting a regex pattern. Navigate results with n (next) or N ( previous). By default, searches are case-insensitive. However, you can modify search sensitivity:

Case-sensitive: Add / at the pattern's end.

/[a-z]/

/[a-z]/

Case-insensitive: Append /i flag.

/[a-z]/i

/[a-z]/i

Printing ​

Fx uses stderr for rendering, allowing you to print values to stdout.

Press p to preview the current value. Press P to print the value to stdout.

You can use fx to select only specific part of the JSON and save it to a file:

curl ... | fx > output.json

curl ... | fx > output.json

Text Selection ​

Text selection in fx differs due to mouse event redirection to stdin. Depending on your terminal, use specific key combinations to select text: