vrk urlinfo

Try it in your browser

vrk, compiled to WebAssembly

# Splits a URL into its parts as JSON.

Command to run

vrk urlinfo 'https://api.example.com:8080/v1/search?q=llm+tools&limit=10'

Enter runs, Shift+Enter adds a line

output

Press RUN. Nothing leaves your browser.

files you can cat:

Edit the command and press RUN. Open the full playground for more recipes, or install vrk to run it on your own files.

vrk urlinfo parses URLs into structured JSON components with dot-path field extraction.

The problem

cut -d'/' -f3 extracts a hostname until a URL has a port number or basic auth. https://api.example.com:8080/path returns “api.example.com:8080” including the port. A URL with user:pass@host breaks the regex entirely. The 10% of URLs that don’t fit a simple pattern break the pipeline.

The solution

vrk urlinfo parses URLs into structured JSON components: scheme, host, port, path, query parameters, fragment, and user. Use --field with a dot-path to extract one component. It handles edge cases that regex approaches miss. It makes no network calls.

Before and after

Before

echo 'https://api.example.com:8080/path?q=test' | cut -d'/' -f3
# Returns "api.example.com:8080" - includes port

After

vrk urlinfo --field host 'https://api.example.com:8080/path?q=test'

Example

vrk urlinfo 'https://api.example.com:8080/v1/search?q=llm+tools&limit=10'

Exit codes

Code	Meaning
0	Success
1	Invalid URL that cannot be parsed, I/O error
2	Interactive TTY with no stdin or positional arg

Flags

Flag	Short	Type	Description
`--field`	-F	string	Extract a single field as plain text (supports dot-path for query params)
`--json`	-j	bool	Append metadata trailer
`--quiet`	-q	bool	Suppress stderr output

How it works

vrk urlinfo splits a URL into its parts (scheme, host, port, path, query, fragment, user) and prints them as JSON.

Full JSON output

$ vrk urlinfo 'https://api.example.com:8080/v1/search?q=llm+tools&limit=10#results'
{"scheme":"https","host":"api.example.com","port":8080,"path":"/v1/search","query":{"limit":"10","q":"llm tools"},"fragment":"results","user":""}

urlinfo puts every URL part in one JSON object. It parses the query parameters into a nested object.

Extract a single field (–field)

$ vrk urlinfo --field host 'https://api.example.com:8080/v1/search'
api.example.com

$ vrk urlinfo --field path 'https://api.example.com:8080/v1/search'
/v1/search

$ vrk urlinfo --field query.q 'https://api.example.com?q=llm+tools'
llm tools

A dot path reaches a query parameter, for example query.q or query.page.

Batch processing

$ printf 'https://a.com/path\nhttps://b.com/other\n' | vrk urlinfo --field host
a.com
b.com

urlinfo reads one URL per line.

JSON metadata (–json)

$ printf 'https://a.com\nhttps://b.com\n' | vrk urlinfo --json
{"scheme":"https","host":"a.com",...}
{"scheme":"https","host":"b.com",...}
{"_vrk":"urlinfo","count":2}

Available fields

Field	Example value
`scheme`	`https`
`host`	`api.example.com`
`port`	`8080` (0 if not specified)
`path`	`/v1/search`
`query`	`{"q":"llm tools","limit":"10"}`
`query.<key>`	value of a specific parameter
`fragment`	`results`
`user`	username (from `user@host` URLs)

Pipeline integration

Group URLs by domain

# Extract unique domains from a list of URLs
cat urls.txt | while IFS= read -r url; do
  vrk urlinfo --field host "$url"
done | sort -u

Extract and decode query parameters

# Get a query parameter and decode it
vrk urlinfo --field query.q 'https://example.com?q=hello%20world' | vrk pct --decode

Count the links on a web page by domain

# Grab a page, extract links, group by domain
vrk grab https://example.com | vrk links --bare | \
  while IFS= read -r url; do
    vrk urlinfo --field host "$url"
  done | sort | uniq -c | sort -rn

When it fails

If the URL is invalid, urlinfo exits 1:

$ vrk urlinfo 'not a url'
error: urlinfo: invalid URL: not a url
$ echo $?
1

If you give no input on an interactive terminal, urlinfo exits 2:

$ vrk urlinfo
usage error: urlinfo: no input: pipe a URL to stdin
$ echo $?
2