clojure.tools.cli
Tools for working with command line arguments.
(cli args & specs)
THIS IS A LEGACY FUNCTION and may be deprecated in the future. Please use
clojure.tools.cli/parse-opts in new applications.
Parse the provided args using the given specs. Specs are vectors
describing a command line argument. For example:
["-p" "--port" "Port to listen on" :default 3000 :parse-fn #(Integer/parseInt %)]
First provide the switches (from least to most specific), then a doc
string, and pairs of options.
Valid options are :default, :parse-fn, and :flag. See
https://github.com/clojure/tools.cli/wiki/Documentation-for-0.2.4 for more
detailed examples.
Returns a vector containing a map of the parsed arguments, a vector
of extra arguments that did not match known switches, and a
documentation banner to provide usage instructions.
(format-lines lens parts)
Format a sequence of summary parts into columns. lens is a sequence of
lengths to use for parts. There are two sequences of lengths if we are
not displaying defaults. There are three sequences of lengths if we
are showing defaults.
(parse-opts args option-specs & options)
Parse arguments sequence according to given option specifications and the
GNU Program Argument Syntax Conventions:
https://www.gnu.org/software/libc/manual/html_node/Argument-Syntax.html
Option specifications are a sequence of vectors with the following format:
[short-opt long-opt-with-required-description description
:property value]
The first three string parameters in an option spec are positional and
optional, and may be nil in order to specify a later parameter.
By default, options are toggles that default to nil, but the second string
parameter may be used to specify that an option requires an argument.
e.g. ["-p" "--port PORT"] specifies that --port requires an argument,
of which PORT is a short description.
The :property value pairs are optional and take precedence over the
positional string arguments. The valid properties are:
:id The key for this option in the resulting option map. This
is normally set to the keywordized name of the long option
without the leading dashes.
Multiple option entries can share the same :id in order to
transform a value in different ways, but only one of these
option entries may contain a :default entry.
This option is mandatory.
:short-opt The short format for this option, normally set by the first
positional string parameter: e.g. "-p". Must be unique.
:long-opt The long format for this option, normally set by the second
positional string parameter; e.g. "--port". Must be unique.
:required A description of the required argument for this option if
one is required; normally set in the second positional
string parameter after the long option: "--port PORT".
The absence of this entry indicates that the option is a
boolean toggle that is set to true when specified on the
command line.
:desc A optional short description of this option.
:default The default value of this option. If none is specified, the
resulting option map will not contain an entry for this
option unless set on the command line.
:default-desc An optional description of the default value. This should be
used when the string representation of the default value is
too ugly to be printed on the command line.
:parse-fn A function that receives the required option argument and
returns the option value.
If this is a boolean option, parse-fn will receive the value
true. This may be used to invert the logic of this option:
["-q" "--quiet"
:id :verbose
:default true
:parse-fn not]
:assoc-fn A function that receives the current option map, the current
option :id, and the current parsed option value, and returns
a new option map.
This may be used to create non-idempotent options, like
setting a verbosity level by specifying an option multiple
times. ("-vvv" -> 3)
["-v" "--verbose"
:default 0
:assoc-fn (fn [m k _] (update-in m [k] inc))]
:validate A vector of [validate-fn validate-msg ...]. Multiple pairs
of validation functions and error messages may be provided.
:validate-fn A vector of functions that receives the parsed option value
and returns a falsy value or throws an exception when the
value is invalid. The validations are tried in the given
order.
:validate-msg A vector of error messages corresponding to :validate-fn
that will be added to the :errors vector on validation
failure.
parse-opts returns a map with four entries:
{:options The options map, keyed by :id, mapped to the parsed value
:arguments A vector of unprocessed arguments
:summary A string containing a minimal options summary
:errors A possible vector of error message strings generated during
parsing; nil when no errors exist}
A few function options may be specified to influence the behavior of
parse-opts:
:in-order Stop option processing at the first unknown argument. Useful
for building programs with subcommands that have their own
option specs.
:no-defaults Only include option values specified in arguments and do not
include any default values in the resulting options map.
Useful for parsing options from multiple sources; i.e. from a
config file and from the command line.
:strict Parse required arguments strictly: if a required argument value
matches any other option, it is considered to be missing (and
you have a parse error).
:summary-fn A function that receives the sequence of compiled option specs
(documented at #'clojure.tools.cli/compile-option-specs), and
returns a custom option summary string.
(summarize specs)
Reduce options specs into a options summary for printing at a terminal.
Note that the specs argument should be the compiled version. That effectively
means that you shouldn't call summarize directly. When you call parse-opts
you get back a :summary key which is the result of calling summarize (or
your user-supplied :summary-fn option) on the compiled option specs.