Class: URI::NI

Inherits:
Generic
  • Object
show all
Defined in:
lib/uri/ni/version.rb,
lib/uri/ni.rb

Constant Summary collapse

VERSION = 
"0.2.2"

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.algorithms(truncated: false) ⇒ Array

Display the available algorithms.

Returns:

  • (Array) —

    containing the symbols representing the available digest algorithms.



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# File 'lib/uri/ni.rb', line 341

def self.algorithms truncated: false
  out = DIGESTS.keys.sort
  truncated ? out : out.reject { |a| /^sha-256-/.match? a }
end

.compute(data = nil, algorithm: :"sha-256", blocksize: 65536, authority: nil, query: nil) {|ctx, buf| ... } ⇒ URI::NI

Compute an RFC6920 URI from a data source.

Parameters:

  • data (#to_s, IO, Digest, nil) (defaults to: nil)
  • algorithm (Symbol) (defaults to: :"sha-256") —

    See available algorithms. Default: :“sha-256”

  • blocksize (Integer) (defaults to: 65536) —

    The number or bytes per call to the Digest

  • authority (String, nil) (defaults to: nil) —

    Optional authority (user, host, port)

  • query (String, nil) (defaults to: nil) —

    Optional query string

Yields:

  • (ctx, buf) —

    Passes the Digest and (maybe) the buffer

Yield Parameters:

  • ctx (Digest::Instance) —

    The digest instance to the block

  • buf (String, nil) —

    The current read buffer (if data is set)

Yield Returns:

  • (nil) —

    The result of the block is ignored

Returns:



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# File 'lib/uri/ni.rb', line 247

def self.compute data = nil, algorithm: :"sha-256", blocksize: 65536,
    authority: nil, query: nil, &block

  build({ scheme: 'ni' }).compute data, algorithm: algorithm,
    blocksize: blocksize, authority: authority, query: query, &block
end

.context(algorithm) ⇒ Digest:Instance

Return a Digest::Instance for a supported algorithm.

Parameters:

  • The (#to_s, #to_sym) —

    algorithm

Returns:

  • (Digest:Instance) —

    The digest context

Raises:

  • (ArgumentError) —

    if the algorithm is unrecognized



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# File 'lib/uri/ni.rb', line 258

def self.context algorithm
  raise ArgumentError, "Cannot coerce #{algorithm} to a symbol" unless
    algorithm.respond_to? :to_s # cheat: symbols respond to to_s
  algorithm = algorithm.to_s.to_sym unless algorithm.is_a? Symbol
  raise ArgumentError, "Unsupported digest algorithm #{algorithm}" unless
    ctx = DIGESTS[algorithm]
  ctx.new
end

.ingest(algorithm = nil, digest) ⇒ URI::NI

Transform a digest for a known algorithm into a URI::NI. Takes a binary, Base64, Base32, or hexadecimal string.

Parameters:

  • algorithm (Symbol, #to_sym) (defaults to: nil) —

    a supported algorithm

  • digest (String, #to_s, Digest::Instance) —

    the digest (or context)

Returns:

  • (URI::NI) —

    the transformed identifier

Raises:

  • (ArgumentError) —

    if the algorithm is unsupported

  • (ArgumentError) —

    if the input string is not the right length for the algorithm

  • (ArgumentError) —

    if the input string is incorrectly encoded



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# File 'lib/uri/ni.rb', line 200

def self.ingest algorithm = nil, digest
  return compute(digest) if digest.is_a? Digest::Instance
  return digest if digest.is_a? URI::NI # noop

  # make sure we're indeed dealing with a string
  digest = digest.to_s

  # just parse if it's already a ni: URI string
  return URI(digest) if /^ni:/i.match? digest

  # get the expected length of the digest for the algorithm
  len = LENGTHS[algorithm.to_s.downcase.to_sym] or raise ArgumentError,
    "unsupported algorithm #{algorithm}"

  # the length of the string is used to determine the expected encoding
  radix = case digest.length
          when len then 256
          when -> x { x >= (len * 8 / 6.0).ceil && x < (len * 8 / 5.0).ceil }
            # note that a length longer than base64 but shorter than base32
            # can be assumed to be base64 with padding
            64
          when (len * 8 / 5.0).ceil then 32
          when len * 2 then 16
          else
            raise ArgumentError, "invalid string length: #{digest.length}"
          end

  # then we lint it to see if it's correct
  digest = transcode digest, from: radix, to: 64

  # then we transcode
  URI("ni:///#{algorithm};#{digest}")
end

.valid_algo?(algorithm) ⇒ true, false

Returns true if the algorithm is supported.

Parameters:

  • algorithm (Symbol, String) —

    the algorithm identifier to test

Returns:

  • (true, false) —

    whether it is supported



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# File 'lib/uri/ni.rb', line 574

def self.valid_algo? algorithm
  algorithm = algorithm.to_s.downcase.to_sym

  # special case for truncated sha-256
  return true if /^(sha-256)-(32|64|96|120|128)$/.match? algorithm

  # etc
  DIGESTS.has_key? algorithm
end

Instance Method Details

#algorithm ⇒ Symbol?

Obtain the algorithm of the digest. May be nil.

Returns:

  • (Symbol, nil) 


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# File 'lib/uri/ni.rb', line 349

def algorithm
  algo = assert_path.first
  return algo.to_sym if algo
end

#algorithm=(algo) ⇒ Symbol?

Set the algorithm of the digest. Will croak if the path is malformed.

Returns:

  • (Symbol, nil) —

    the old algorithm



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# File 'lib/uri/ni.rb', line 357

def algorithm= algo
  a, b = assert_path
  self.path   = "/#{algo}"
  self.set_digest(b, radix: 64) if b
  a.to_sym if a
end

#authority ⇒ String?

Obtain the authority (userinfo@host:port) if present.

Returns:

  • (String, nil) —

    the authority



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# File 'lib/uri/ni.rb', line 367

def authority
  out = userinfo ? "#{userinfo}@#{host}" : host
  out += "#{out}:#{port}" if port
  out
end

#authority=(authority) ⇒ String?

Set the authority of the URI.

Returns:

  • (String, nil) —

    the old authority



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# File 'lib/uri/ni.rb', line 376

def authority= authority
  old = self.authority
  u, h, p = assert_authority authority unless authority.nil?
  set_userinfo u
  set_host     h
  set_port     p
  old
end

#b32digest(alt: false) ⇒ String

Return the digest in its base32 notation. Optionally give alt: a truthy value to return an alternate (lowercase) representation. Note this method requires the base32 module.

Parameters:

  • alt (false, true) (defaults to: false) —

    Return the alternative representation

Returns:

  • (String) —

    The base32 digest



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# File 'lib/uri/ni.rb', line 474

def b32digest alt: false
  transcode raw_digest, from: 64, to: 32, alt: alt
end

#b32digest=(value) ⇒ String, ...

Set the digest value, assuming a base32 input (requires base32).

Parameters:

  • value (String, nil, Digest::Instance) —

    the new digest

Returns:

  • (String, nil, Digest::Instance) —

    the value passed in



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# File 'lib/uri/ni.rb', line 481

def b32digest= value
  set_digest value, radix: 32
end

#b64digest(alt: false) ⇒ String

Return the digest in its base64 notation. Note it is the default representation that is URL-safe, for parity with the identifier itself. Give alt: a truthy value to return a plain (non-URL-safe) base64 representation.

Parameters:

  • alt (false, true) (defaults to: false) —

    Return the alternative representation

Returns:

  • (String) —

    The base64 digest



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# File 'lib/uri/ni.rb', line 493

def b64digest alt: false
  transcode raw_digest, from: 64, to: 64, alt: alt
end

#b64digest=(value) ⇒ String, ...

Set the digest value, assuming a base64 input.

Parameters:

  • value (String, nil, Digest::Instance) —

    the new digest

Returns:

  • (String, nil, Digest::Instance) —

    the value passed in



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# File 'lib/uri/ni.rb', line 500

def b64digest= value
  set_digest value, radix: 64
end

#compute(data = nil, algorithm: nil, blocksize: 65536, authority: nil, query: nil, &block) ⇒ Object

(Re)-compute a digest using existing information from an instance.

Raises:

  • (ArgumentError)

See Also:



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# File 'lib/uri/ni.rb', line 269

def compute data = nil, algorithm: nil, blocksize: 65536,
    authority: nil, query: nil, &block

  # enforce block size
  raise ArgumentError,
    "Blocksize must be an integer >0, not #{blocksize}" unless
    blocksize.is_a? Integer and blocksize > 0

  # special case for when the data is a digest
  ctx = nil
  if data.is_a? Digest::Instance
    # note the self; this would have been a bug lol
    self.algorithm = algorithm ||= algo_for data, algorithm
    ctx  = data
    data = nil # unset data
  else
    # make sure we're all on the same page hurr
    self.algorithm = algorithm ||= self.algorithm || :"sha-256"
    raise URI::InvalidComponentError,
      "Can't resolve a Digest context for the algorithm #{algorithm}." unless
      ctx = DIGESTS[algorithm]
    ctx = ctx.new
  end

  # deal with authority component
  if authm = AUTH_RE.match(authority.to_s)
    userinfo, host, port = authm.captures
    set_userinfo userinfo
    set_host     host.to_s
    set_port     port
  end

  # coerce data to something non-null
  data = data.to_s if (data.class.ancestors & [String, IO, NilClass]).empty?
  if data
    data = StringIO.new data unless data.is_a? IO

    # give us a default block
    block ||= -> x, y { x << y } # unless block_given?

    while buf = data.read(blocksize)
      block.call ctx, buf
    end
  elsif block
    block.call ctx, nil
  end

  set_digest ctx.digest

  self
end

#digest(radix: 256, alt: false) ⇒ String

Return the digest in the hash. Optionally takes a radix: argument to specify binary, base64, base32, or hexadecimal representations. Another optional flag will return alternative representations for each: base64url (vanilla base64 is canonical), base32 in lowercase (uppercase is canonical), hexadecimal in uppercase (lowercase is canonical). The binary representation naturally has no alternative form. Base64/base32 values will be appropriately padded.

Parameters:

  • radix (256, 64, 32, 16) (defaults to: 256) —

    The radix of the representation

  • alt (false, true) (defaults to: false) —

    Return the alternative representation

Returns:

  • (String) —

    The digest of the URI in the given representation



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# File 'lib/uri/ni.rb', line 398

def digest radix: 256, alt: false
  assert_radix radix
  transcode raw_digest, from: 64, to: radix, alt: alt
end

#digest=(value) ⇒ String, ...

Set the digest to the data. Data may either be a Digest::Instance or a binary string. Digest::Instance objects will just be run through #compute, with all that entails.

Parameters:

  • value (String, nil, Digest::Instance) —

    the new digest

Returns:

  • (String, nil, Digest::Instance) —

    the value passed in



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# File 'lib/uri/ni.rb', line 445

def digest= value
  return set_digest value
end

#hexdigest(alt: false) ⇒ String

Return the digest in its hexadecimal notation. Optionally give alt: a truthy value to return an alternate (uppercase) representation.

Parameters:

  • alt (false, true) (defaults to: false) —

    Return the alternative representation

Returns:

  • (String) —

    The hexadecimal digest



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# File 'lib/uri/ni.rb', line 456

def hexdigest alt: false
  transcode raw_digest, from: 64, to: 16, alt: alt
end

#hexdigest=(value) ⇒ String, ...

Set the digest value, assuming a hexadecimal input.

Parameters:

  • value (String, nil, Digest::Instance) —

    the new digest

Returns:

  • (String, nil, Digest::Instance) —

    the value passed in



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# File 'lib/uri/ni.rb', line 463

def hexdigest= value
  set_digest value, radix: 16
end

#set_digest(value, radix: 256) ⇒ String

Set the digest to the data, with an optional radix. Data may either be a Digest::Instance—in which case the radix is ignored—a string, or nil. Digest::Instance objects will just be run through #compute, with all that entails.

Parameters:

  • value (String, nil, Digest::Instance) —

    The new digest

  • radix (256, 64, 32, 16) (defaults to: 256) —

    The radix of the encoding (default 256)

Returns:

  • (String) —

    The old digest in the given radix



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# File 'lib/uri/ni.rb', line 412

def set_digest value, radix: 256
  assert_radix radix

  a, d = assert_path

  case value
  when Digest::Instance
    compute value
  when String
    value = transcode value, from: radix
    value = value[0, LENGTHS[a.to_sym]] # deal with truncation
    value = transcode value, to: 64

    self.path = a ? "/#{a};#{value}" : "/;#{value}"
  when nil
    self.path = a ? "/#{a}" : ?/
  else
    raise ArgumentError,
      "Value must be a string or Digest::Instance, not #{value.class}"
  end

  # bail out if nil
  return unless d
  transcode d, from: 64, to: radix
end

#to_http(authority: nil) ⇒ URI::HTTP

Unconditionally returns an HTTP URL.

Parameters:

  • authority (#to_s, URI) (defaults to: nil) —

    Override the authority part of the URI

Returns:

  • (URI::HTTP) 


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# File 'lib/uri/ni.rb', line 566

def to_http authority: nil
  to_www https: false, authority: authority
end

#to_https(authority: nil) ⇒ URI::HTTPS

Unconditionally returns an HTTPS URL.

Parameters:

  • authority (#to_s, URI) (defaults to: nil) —

    Override the authority part of the URI

Returns:

  • (URI::HTTPS) 


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# File 'lib/uri/ni.rb', line 556

def to_https authority: nil
  # note we don't simply alias this
  to_www authority: authority
end

#to_www(https: true, authority: nil) ⇒ URI::HTTPS, URI::HTTP

Returns a /.well-known/..., either HTTPS or HTTP URL, given the contents of the ni: URI.

Parameters:

  • authority (#to_s, URI) (defaults to: nil) —

    Override the authority part of the URI

  • https (true, false) (defaults to: true) —

    Whether the URL is to be HTTPS.

Returns:

  • (URI::HTTPS, URI::HTTP) —

    The generated URL.



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# File 'lib/uri/ni.rb', line 511

def to_www https: true, authority: nil
  a, d = assert_path
  components = {
    scheme:   "http#{https ? ?s : ''}",
    userinfo: userinfo,
    host:     host,
    port:     port,
    path:     "/.well-known/ni/#{a}/#{d}",
    query:    query,
    fragment: fragment,
  }

  if authority
    uhp = []
    if authority.is_a? URI
      raise URI::InvalidComponentError, "Bad authority #{authority}" unless
        %i[userinfo host port].all? {|c| authority.respond_to? c }
      uhp = [authority.userinfo, authority.host, authority.port]
      uhp[2] = nil if authority.port == authority.class::DEFAULT_PORT
    else
      authority = authority.to_s
      uhp = AUTH_RE.match(authority) or raise URI::InvalidComponentError,
        "Invalid authority #{authority}"
      uhp = uhp.captures
    end
    components[:userinfo] = uhp[0]
    components[:host]     = uhp[1]
    components[:port]     = uhp[2]
  end

  # pick the class
  cls = https ? URI::HTTPS : URI::HTTP

  # `normalize` should do this but doesn't
  components[:port] = nil if
    components[:port] and components[:port] == cls::DEFAULT_PORT

  cls.build(components).normalize
end

#truncated? ⇒ false, true

Returns true if the algorithm is a truncated one.

Returns:

  • (false, true) 


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# File 'lib/uri/ni.rb', line 333

def truncated?
  TRUNCATED.include? algorithm
end

#valid? ⇒ false, true

Returns true if the digest length matches the algorithm.

Returns:

  • (false, true) 


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# File 'lib/uri/ni.rb', line 325

def valid?
  LENGTHS[algorithm] and LENGTHS[algorithm] == digest.length
end