trurl - Man Page

transpose URLs

Description

trurl parses, manipulates and outputs URLs and parts of URLs.

It uses the RFC 3986 definition of URLs and it uses libcurl's URL parser to do so, which includes a few "extensions". The URL support is limited to "hierarchical" URLs, the ones that use :// separators after the scheme.

Typically you pass in one or more URLs and decide what of that you want output. Possibly modifying the URL as well.

trurl knows URLs and every URL consists of up to ten separate and independent components. These components can be extracted, removed and updated with trurl and they are referred to by their respective names: scheme, user, password, options, host, port, path, query, fragment and zoneid.

Normalization

When provided a URL to work with, trurl "normalizes" it. It means that individual URL components are URL decoded then URL encoded back again and set in the URL.

Example:

$ trurl 'http://ex%61mple:80/%62ath/a/../b?%2e%FF#tes%74'
http://example/bath/b?.%ff#test

Options

Options start with one or two dashes. Many of the options require an additional value next to them.

Any other argument is interpreted as a URL argument, and is treated as if it was following a --url option.

The first argument that is exactly two dashes (--), marks the end of options; any argument after the end of options is interpreted as a URL argument even if it starts with a dash.

Long options can be provided either as --flag argument or as --flag=argument.

-a, --append [component]=[data]

Append data to a component. This can only append data to the path and the query components.

For path, this URL encodes and appends the new segment to the path, separated with a slash.

For query, this URL encodes and appends the new segment to the query, separated with an ampersand (&). If the appended segment contains an equal sign (=) that one is kept verbatim and both sides of the first occurrence are URL encoded separately.

--accept-space

When set, trurl tries to accept spaces as part of the URL and instead URL encode such occurrences accordingly.

According to RFC 3986, a space cannot legally be part of a URL. This option provides a best-effort to convert the provided string into a valid URL.

--as-idn

Converts a punycode ASCII hostname to its original International Domain Name in Unicode. If the hostname is not using punycode then the original hostname is used.

--curl

Only accept URL schemes supported by libcurl.

--default-port

When set, trurl uses the scheme's default port number for URLs with a known scheme, and without an explicit port number.

Note that trurl only knows default port numbers for URL schemes that are supported by libcurl.

Since, by default, trurl removes default port numbers from URLs with a known scheme, this option is pretty much ignored unless one of --get, --json, and --keep-port is not also specified.

-f, --url-file [filename]

Read URLs to work on from the given file. Use the filename - (a single minus) to tell trurl to read the URLs from stdin.

Each line needs to be a single valid URL. trurl removes one carriage return character at the end of the line if present, trims off all the trailing space and tab characters, and skips all empty (after trimming) lines.

The maximum line length supported in a file like this is 4094 bytes. Lines that exceed that length are skipped, and a warning is printed to stderr when they are encountered.

-g, --get [format]

Output text and URL data according to the provided format string. Components from the URL can be output when specified as {component} or [component], with the name of the part show within curly braces or brackets. You can not mix braces and brackets for this purpose in the same command line.

The following component names are available (case sensitive): url, scheme, user, password, options, host, port, path, query, fragment and zoneid.

{component} expands to nothing if the given component does not have a value.

Components are shown URL decoded by default.

URL decoding a component may cause problems to display it. Such problems make a warning get displayed unless --quiet is used.

trurl supports a range of different qualifiers, or prefixes, to the component that changes how it handles it:

If url: is specified, like {url:path}, the component gets output URL encoded. As a shortcut, url: also works written as a single colon: {:path}.

If strict: is specified, like {strict:path}, URL decode problems are turned into errors. In this stricter mode, a URL decode problem makes trurl stop what it is doing and return with exit code 10.

If must: is specified, like {must:query}, it makes trurl return an error if the requested component does not exist in the URL. By default a missing component will just be shown blank.

If default: is specified, like {default:url} or {default:port}, and the port is not explicitly specified in the URL, the scheme's default port is output if it is known.

If puny: is specified, like {puny:url} or {puny:host}, the punycoded version of the hostname is used in the output. This option is mutually exclusive with idn:.

If idn: is specified like {idn:url} or {idn:host}, the International Domain Name version of the hostname is used in the output if it is provided as a correctly encoded punycode version. This option is mutually exclusive with puny:.

If --default-port is specified, all formats are expanded as if they used default:; and if --punycode is used, all formats are expanded as if they used puny:. Also note that {url} is affected by the --keep-port option.

Hosts provided as IPv6 numerical addresses are provided within square brackets. Like [fe80::20c:29ff:fe9c:409b].

Hosts provided as IPv4 numerical addresses are normalized and provided as four dot-separated decimal numbers when output.

You can access specific keys in the query string using the format {query:key}. Then the value of the first matching key is output using a case sensitive match. When extracting a URL decoded query key that contains %00, such octet is replaced with a single period . in the output.

You can access specific keys in the query string and out all values using the format {query-all:key}. This looks for key case sensitively and outputs all values for that key space-separated.

The format string supports the following backslash sequences:

\ - backslash

\t - tab

\n - newline

\r - carriage return

\{ - an open curly brace that does not start a variable

\[ - an open bracket that does not start a variable

All other text in the format string is shown as-is.

-h, --help

Show the help output.

--iterate [component]=[item1 item2 ...]

Set the component to multiple values and output the result once for each iteration. Several combined iterations are allowed to generate combinations, but only one --iterate option per component. The listed items to iterate over should be separated by single spaces.

Example:

$ trurl example.com --iterate=scheme="ftp https" --iterate=port="22 80"
ftp://example.com:22/
ftp://example.com:80/
https://example.com:22/
https://example.com:80/

--json

Outputs all set components of the URLs as JSON objects. All components of the URL that have data get populated in the parts object using their component names. See below for details on the format.

The URL components are provided URL decoded. Change that with --urlencode.

--keep-port

By default, trurl removes default port numbers from URLs with a known scheme even if they are explicitly specified in the input URL. This options, makes trurl not remove them.

Example:

$ trurl https://example.com:443/ --keep-port
https://example.com:443/

--no-guess-scheme

Disables libcurl's scheme guessing feature. URLs that do not contain a scheme are treated as invalid URLs.

Example:

$ trurl example.com --no-guess-scheme
trurl note: Bad scheme [example.com]

--punycode

Uses the punycode version of the hostname, which is how International Domain Names are converted into plain ASCII. If the hostname is not using IDN, the regular ASCII name is used.

Example:

$ trurl http://åäö/ --punycode
http://xn--4cab6c/

--qtrim [what]

Trims data off a query.

what is specified as a full name of a name/value pair, or as a word prefix (using a single trailing asterisk (*)) which makes trurl remove the tuples from the query string that match the instruction.

To match a literal trailing asterisk instead of using a wildcard, escape it with a backslash in front of it. Like \*.

--query-separator [what]

Specify the single letter used for separating query pairs. The default is & but at least in the past sometimes semicolons ; or even colons : have been used for this purpose. If your URL uses something other than the default letter, setting the right one makes sure trurl can do its query operations properly.

Example:

$ trurl "https://curl.se?b=name:a=age" --sort-query --query-separator ":"
https://curl.se/?a=age:b=name

--quiet

Suppress (some) notes and warnings.

--redirect [URL]

Redirect the URL to this new location. The redirection is performed on the base URL, so, if no base URL is specified, no redirection is performed.

Example:

$ trurl --url https://curl.se/we/are.html --redirect ../here.html
https://curl.se/here.html

--replace [data]

Replaces a URL query.

data can either take the form of a single value, or as a key/value pair in the shape foo=bar. If replace is called on an item that is not in the list of queries trurl ignores that item.

trurl URL encodes both sides of the = character in the given input data argument.

--replace--append [data]

Works the same as --replace, but trurl appends a missing query string if it is not in the query list already.

-s, --set [component][:]=[data]

Set this URL component. Setting blank string ("") clears the component from the URL.

The following components can be set: url, scheme, user, password, options, host, port, path, query, fragment and zoneid.

If a simple =-assignment is used, the data is URL encoded when applied. If := is used, the data is assumed to already be URL encoded and stored as-is.

If ?= is used, the set is only performed if the component is not already set. It avoids overwriting any already set data.

You can also combine : and ? into ?:= if desired.

If no URL or --url-file argument is provided, trurl tries to create a URL using the components provided by the --set options. If not enough components are specified, this fails.

--sort-query

The "variable=content" tuplets in the query component are sorted in a case insensitive alphabetical order. This helps making URLs identical that otherwise only had their query pairs in different orders.

--trim [component]=[what]

Deprecated: use --qtrim.

Trims data off a component. Currently this can only trim a query component.

what is specified as a full word or as a word prefix (using a single trailing asterisk (*)) which makes trurl remove the tuples from the query string that match the instruction.

To match a literal trailing asterisk instead of using a wildcard, escape it with a backslash in front of it. Like \*.

--url [URL]

Set the input URL to work with. The URL may be provided without a scheme, which then typically is not actually a legal URL but trurl tries to figure out what is meant and guess what scheme to use (unless --no-guess-scheme is used).

Providing multiple URLs makes trurl act on all URLs in a serial fashion.

If the URL cannot be parsed for whatever reason, trurl simply moves on to the next provided URL - unless --verify is used.

--urlencode

Outputs URL encoded version of components by default when using --get or --json.

-v, --version

Show version information and exit.

--verify

When a URL is provided, return error immediately if it does not parse as a valid URL. In normal cases, trurl can forgive a bad URL input.

URL Components

scheme

This is the leading character sequence of a URL, excluding the "://" separator. It cannot be specified URL encoded.

A URL cannot exist without a scheme, but unless --no-guess-scheme is used trurl guesses what scheme that was intended if none was provided.

Examples:

$ trurl https://odd/ -g '{scheme}'
https

$ trurl odd -g '{scheme}'
http

$ trurl odd -g '{scheme}' --no-guess-scheme
trurl note: Bad scheme [odd]

user

After the scheme separator, there can be a username provided. If it ends with a colon (:), there is a password provided. If it ends with an at character (@) there is no password provided in the URL.

Example:

$ trurl https://user%3a%40:secret@odd/ -g '{user}'
user:@

password

If the password ends with a semicolon (;) there is an options field following. This field is only accepted by trurl for URLs using the IMAP scheme.

Example:

$ trurl https://user:secr%65t@odd/ -g '{password}'
secret

options

This field can only end with an at character (@) that separates the options from the hostname.

$ trurl 'imap://user:pwd;giraffe@odd' -g '{options}'
giraffe

If the scheme is not IMAP, the giraffe part is instead considered part of the password:

$ trurl 'sftp://user:pwd;giraffe@odd' -g '{password}'
pwd;giraffe

We strongly advice users to %-encode ;, : and @ in URLs of course to reduce the risk for confusions.

host

The host component is the hostname or a numerical IP address. If a hostname is provided, it can be an International Domain Name non-ASCII characters. A hostname can be provided URL encoded.

trurl provides options for working with the IDN hostnames either as IDN or in its punycode version.

Example, convert an IDN name to punycode in the output:

$ trurl http://åäö/ --punycode
http://xn--4cab6c/

Or the reverse, convert a punycode hostname into its IDN version:

$ trurl http://xn--4cab6c/ --as-idn
http://åäö/

If the URL's hostname starts with an open bracket ([) it is a numerical IPv6 address that also must end with a closing bracket (]). trurl normalizes IPv6 addreses.

Example:

$ trurl 'http://[2001:9b1:0:0:0:0:7b97:364b]/'
http://[2001:9b1::7b97:364b]/

A numerical IPV4 address can be specified using one, two, three or four numbers separated with dots and they can use decimal, octal or hexadecimal. trurl normalizes provided addresses and uses four dotted decimal numbers in its output.

Examples:

$ trurl http://646464646/
http://38.136.68.134/

$ trurl http://246.646/
http://246.0.2.134/

$ trurl http://246.46.646/
http://246.46.2.134/

$ trurl http://0x14.0xb3022/
http://20.11.48.34/

zoneid

If the provided host is an IPv6 address, it might contain a specific zoneid. A number or a network interface name normally.

Example:

$ trurl 'http://[2001:9b1::f358:1ba4:7b97:364b%enp3s0]/' -g '{zoneid}'
enp3s0

port

If the host ends with a colon (:) then a port number follows. It is a 16 bit decimal number that may not be URL encoded.

trurl knows the default port number for many URL schemes so it can show port numbers for a URL even if none was explicitly used in the URL. With --default-port it can add the default port to a URL even when not provide.

Example:

$ trurl http:/a --default-port
http://a:80/

Similarly, trurl normally hides the port number if the given number is the default.

Example:

$ trurl http:/a:80
http://a/

But a user can make trurl keep the port even if it is the default, with --keep-port.

Example:

$ trurl http:/a:80 --keep-port
http://a:80/

path

A URL path is assumed to always start with and contain at least a slash (/), even if none is actually provided in the URL.

Example:

$ trurl http://xn--4cab6c -g '[path]'
/

When setting the path, trurl will inject a leading slash if none is provided:

$ trurl http://hello -s path="pony"
http://hello/pony

$ trurl http://hello -s path="/pony"
http://hello/pony

If the input path contains dotdot or dot-slash sequences, they are normalized away.

Example:

$ trurl http://hej/one/../two/../three/./four
http://hej/three/four

You can append a new segment to an existing path with --append like this:

$ trurl http://twelve/three?hello --append path=four
http://twelve/three/four?hello

query

The query part does not include the leading question mark (?) separator when extracted with trurl.

Example:

$ trurl http://horse?elephant -g '{query}'
elephant

Example, if you set the query with a leading question mark:

$ trurl http://horse?elephant -s "query=?elephant"
http://horse/?%3felephant

Query parts are often made up of a series of name=value pairs separated with ampersands (&), and trurl offers several ways to work with such.

Append a new name value pair to a URL with --append:

$ trurl http://host?name=hello --append query=search=life
http://host/?name=hello&search=life

You cam --replace the value of a specific existing name among the pairs:

$ trurl 'http://alpha?one=real&two=fake' --replace two=alsoreal
http://alpha/?one=real&two=alsoreal

If the specific name you want to replace perhaps does not exist in the URL, you can opt to replace or append the pair:

$ trurl 'http://alpha?one=real&two=fake' --replace-append three=alsoreal
http://alpha/?one=real&two=fake&three=alsoreal

In order to perhaps compare two URLs using query name value pairs, sorting them first at least increases the chances of it working:

$ trurl "http://alpha/?one=real&two=fake&three=alsoreal" --sort-query
http://alpha/?one=real&three=alsoreal&two=fake

Remove name/value pairs from the URL by specifying exact name or wildcard pattern with --qtrim:

$ trurl 'https://example.com?a12=hej&a23=moo&b12=foo' --qtrim a*'
https://example.com/?b12=foo

fragment

The fragment part does not include the leading hash sign (#) separator when extracted with trurl.

Example:

$ trurl http://horse#elephant -g '{fragment}'
elephant

Example, if you set the fragment with a leading hash sign:

$ trurl "http://horse#elephant" -s "fragment=#zebra"
http://horse/#%23zebra

The fragment part of a URL is for local purposes only. The data in there is never actually sent over the network when a URL is used for transfers.

url

trurl supports url as a named component for --get to allow for more powerful outputs, but of course it is not actually a "component"; it is the full URL.

Example:

$ trurl ftps://example.com:2021/p%61th -g '{url}'
ftps://example.com:2021/path

JSON output format

The --json option outputs a JSON array with one or more objects. One for each URL. Each URL JSON object contains a number of properties, a series of key/value pairs. The exact set present depends on the given URL.

url

This key exists in every object. It is the complete URL. Affected by --default-port, --keep-port, and --punycode.

parts

This key exists in every object, and contains an object with a key for each of the settable URL components. If a component is missing, it means it is not present in the URL. The parts are URL decoded unless --urlencode is used.

parts.scheme

The URL scheme.

parts.user

The username.

parts.password

The password.

parts.options

The options. Note that only a few URL schemes support the "options" component.

parts.host

The normalized hostname. It might be a UTF-8 name if an IDN name was used. It can also be a normalized IPv4 or IPv6 address. An IPv6 address always starts with a bracket ([) - and no other hostnames can contain such a symbol. If --punycode is used, the punycode version of the host is outputted instead.

parts.port

The provided port number as a string. If the port number was not provided in the URL, but the scheme is a known one, and --default-port is in use, the default port for that scheme is provided here.

parts.path

The path. Including the leading slash.

parts.query

The full query, excluding the question mark separator.

parts.fragment

The fragment, excluding the pound sign separator.

parts.zoneid

The zone id, which can only be present in an IPv6 address. When this key is present, then host is an IPv6 numerical address.

params

This key contains an array of query key/value objects. Each such pair is listed with "key" and "value" and their respective contents in the output.

The key/values are extracted from the query where they are separated by ampersands (&) - or the user sets with --query-separator.

The query pairs are listed in the order of appearance in a left-to-right order, but can be made alpha-sorted with --sort-query.

It is only present if the URL has a query.

Examples

Replace the hostname of a URL

$ trurl --url https://curl.se --set host=example.com
https://example.com/

Create a URL by setting components

 $ trurl --set host=example.com --set scheme=ftp
 ftp://example.com/

Redirect a URL

$ trurl --url https://curl.se/we/are.html --redirect here.html
https://curl.se/we/here.html

Change port number

This also shows how trurl removes dot-dot sequences

$ trurl --url https://curl.se/we/../are.html --set port=8080
https://curl.se:8080/are.html

Extract the path from a URL

$ trurl --url https://curl.se/we/are.html --get '{path}'
/we/are.html

Extract the port from a URL

This gets the default port based on the scheme if the port is not set in the URL.

$ trurl --url https://curl.se/we/are.html --get '{default:port}'
443

Append a path segment to a URL

$ trurl --url https://curl.se/hello --append path=you
https://curl.se/hello/you

Append a query segment to a URL

$ trurl --url "https://curl.se?name=hello" --append query=search=string
 https://curl.se/?name=hello&search=string

Read URLs from stdin

$ cat urllist.txt | trurl --url-file -
\&...

Output JSON

$ trurl "https://fake.host/search?q=answers&user=me#frag" --json
[
  {
    "url": "https://fake.host/search?q=answers&user=me#frag",
    "parts": [
        "scheme": "https",
        "host": "fake.host",
        "path": "/search",
        "query": "q=answers&user=me"
        "fragment": "frag",
    ],
    "params": [
      {
        "key": "q",
        "value": "answers"
      },
      {
        "key": "user",
        "value": "me"
      }
    ]
  }
]

Remove tracking tuples from query

$ trurl "https://curl.se?search=hey&utm_source=tracker" --qtrim "utm_*"
https://curl.se/?search=hey

Show a specific query key value

$ trurl "https://example.com?a=home&here=now&thisthen" -g '{query:a}'
home

Sort the key/value pairs in the query component

$ trurl "https://example.com?b=a&c=b&a=c" --sort-query
https://example.com?a=c&b=a&c=b

Work with a query that uses a semicolon separator

$ trurl "https://curl.se?search=fool;page=5" --qtrim "search" --query-separator ";"
https://curl.se?page=5

Accept spaces in the URL path

$ trurl "https://curl.se/this has space/index.html" --accept-space
https://curl.se/this%20has%20space/index.html

Create multiple variations of a URL with different schemes

$ trurl "https://curl.se/path/index.html" --iterate "scheme=http ftp sftp"
http://curl.se/path/index.html
ftp://curl.se/path/index.html
sftp://curl.se/path/index.html