pater (version 1.0.0)

parse: Decompose a pathname

Description

This function decomposes a given pathname into meaningful tokens, see Details.

Usage

parse(path, encodePath = identity)

Value

An object of class tokenData.

Arguments

path

A character vector of length 1.

encodePath

A function to encode characters, defaults to the identity function.

Details

The parse function returns a tokenData object which contains a list of tokens from the path you provided. A token is a meaningful portion of a given pathname, it can contain so called "parameters", which are placeholders that will be filled when a new HTTP request comes in, these parameters may or not expand a whole path segment, meaning that two parameters can share the same path segment, a token type can be any of the following:

• text: Represents a fixed path portion , e.g "/path/" or "/path/resource".

• param: Represent a dynamic path portion, e.g. "/path/:Id" or "/path/:from-:to". Must be named.

• wildcard: Similar to param but can "expand" itself into more than one path segment, e.g. "/public/*files". Must be named

• group: Represents an optional path portion, either an optional parameter or optional text, e.g. "/path{/:optional}" or "/user{s}".

pater uses this special syntax as some regex features are not available, e.g. "/users?" doesn't work, this was done in the original implementation for security reasons. If you want to specify one of these in your path use double backlash, "/users\?"

Examples

# A "fixed" path
path <- "/path/resource"
parse(path)

# Parameters
path <- "/path/to/:resourceId"
parse(path)

# Wildcard
path <- "/path/*files"
parse(path)

# Group or "optional"
path <- "/path{s}"
parse(path)

# Error because of regex feature not supported
if (FALSE) {
 path <- "/paths?"
 parse(path)
}

# Escape it
path <- "/paths\\?"
parse(path)