/Languages/Ruby/StdLib/ruby/1.9.1/csv.rb
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- # encoding: US-ASCII
- # = csv.rb -- CSV Reading and Writing
- #
- # Created by James Edward Gray II on 2005-10-31.
- # Copyright 2005 James Edward Gray II. You can redistribute or modify this code
- # under the terms of Ruby's license.
- #
- # See CSV for documentation.
- #
- # == Description
- #
- # Welcome to the new and improved CSV.
- #
- # This version of the CSV library began its life as FasterCSV. FasterCSV was
- # intended as a replacement to Ruby's then standard CSV library. It was
- # designed to address concerns users of that library had and it had three
- # primary goals:
- #
- # 1. Be significantly faster than CSV while remaining a pure Ruby library.
- # 2. Use a smaller and easier to maintain code base. (FasterCSV eventually
- # grew larger, was also but considerably richer in features. The parsing
- # core remains quite small.)
- # 3. Improve on the CSV interface.
- #
- # Obviously, the last one is subjective. I did try to defer to the original
- # interface whenever I didn't have a compelling reason to change it though, so
- # hopefully this won't be too radically different.
- #
- # We must have met our goals because FasterCSV was renamed to CSV and replaced
- # the original library.
- #
- # == What's Different From the Old CSV?
- #
- # I'm sure I'll miss something, but I'll try to mention most of the major
- # differences I am aware of, to help others quickly get up to speed:
- #
- # === CSV Parsing
- #
- # * This parser is m17n aware. See CSV for full details.
- # * This library has a stricter parser and will throw MalformedCSVErrors on
- # problematic data.
- # * This library has a less liberal idea of a line ending than CSV. What you
- # set as the <tt>:row_sep</tt> is law. It can auto-detect your line endings
- # though.
- # * The old library returned empty lines as <tt>[nil]</tt>. This library calls
- # them <tt>[]</tt>.
- # * This library has a much faster parser.
- #
- # === Interface
- #
- # * CSV now uses Hash-style parameters to set options.
- # * CSV no longer has generate_row() or parse_row().
- # * The old CSV's Reader and Writer classes have been dropped.
- # * CSV::open() is now more like Ruby's open().
- # * CSV objects now support most standard IO methods.
- # * CSV now has a new() method used to wrap objects like String and IO for
- # reading and writing.
- # * CSV::generate() is different from the old method.
- # * CSV no longer supports partial reads. It works line-by-line.
- # * CSV no longer allows the instance methods to override the separators for
- # performance reasons. They must be set in the constructor.
- #
- # If you use this library and find yourself missing any functionality I have
- # trimmed, please {let me know}[mailto:james@grayproductions.net].
- #
- # == Documentation
- #
- # See CSV for documentation.
- #
- # == What is CSV, really?
- #
- # CSV maintains a pretty strict definition of CSV taken directly from
- # {the RFC}[http://www.ietf.org/rfc/rfc4180.txt]. I relax the rules in only one
- # place and that is to make using this library easier. CSV will parse all valid
- # CSV.
- #
- # What you don't want to do is feed CSV invalid data. Because of the way the
- # CSV format works, it's common for a parser to need to read until the end of
- # the file to be sure a field is invalid. This eats a lot of time and memory.
- #
- # Luckily, when working with invalid CSV, Ruby's built-in methods will almost
- # always be superior in every way. For example, parsing non-quoted fields is as
- # easy as:
- #
- # data.split(",")
- #
- # == Questions and/or Comments
- #
- # Feel free to email {James Edward Gray II}[mailto:james@grayproductions.net]
- # with any questions.
- require "forwardable"
- require "English"
- require "date"
- require "stringio"
- #
- # This class provides a complete interface to CSV files and data. It offers
- # tools to enable you to read and write to and from Strings or IO objects, as
- # needed.
- #
- # == Reading
- #
- # === From a File
- #
- # ==== A Line at a Time
- #
- # CSV.foreach("path/to/file.csv") do |row|
- # # use row here...
- # end
- #
- # ==== All at Once
- #
- # arr_of_arrs = CSV.read("path/to/file.csv")
- #
- # === From a String
- #
- # ==== A Line at a Time
- #
- # CSV.parse("CSV,data,String") do |row|
- # # use row here...
- # end
- #
- # ==== All at Once
- #
- # arr_of_arrs = CSV.parse("CSV,data,String")
- #
- # == Writing
- #
- # === To a File
- #
- # CSV.open("path/to/file.csv", "wb") do |csv|
- # csv << ["row", "of", "CSV", "data"]
- # csv << ["another", "row"]
- # # ...
- # end
- #
- # === To a String
- #
- # csv_string = CSV.generate do |csv|
- # csv << ["row", "of", "CSV", "data"]
- # csv << ["another", "row"]
- # # ...
- # end
- #
- # == Convert a Single Line
- #
- # csv_string = ["CSV", "data"].to_csv # to CSV
- # csv_array = "CSV,String".parse_csv # from CSV
- #
- # == Shortcut Interface
- #
- # CSV { |csv_out| csv_out << %w{my data here} } # to $stdout
- # CSV(csv = "") { |csv_str| csv_str << %w{my data here} } # to a String
- # CSV($stderr) { |csv_err| csv_err << %w{my data here} } # to $stderr
- #
- # == CSV and Character Encodings (M17n or Multilingualization)
- #
- # This new CSV parser is m17n savvy. The parser works in the Encoding of the IO
- # or String object being read from or written to. Your data is never transcoded
- # (unless you ask Ruby to transcode it for you) and will literally be parsed in
- # the Encoding it is in. Thus CSV will return Arrays or Rows of Strings in the
- # Encoding of your data. This is accomplished by transcoding the parser itself
- # into your Encoding.
- #
- # Some transcoding must take place, of course, to accomplish this multiencoding
- # support. For example, <tt>:col_sep</tt>, <tt>:row_sep</tt>, and
- # <tt>:quote_char</tt> must be transcoded to match your data. Hopefully this
- # makes the entire process feel transparent, since CSV's defaults should just
- # magically work for you data. However, you can set these values manually in
- # the target Encoding to avoid the translation.
- #
- # It's also important to note that while all of CSV's core parser is now
- # Encoding agnostic, some features are not. For example, the built-in
- # converters will try to transcode data to UTF-8 before making conversions.
- # Again, you can provide custom converters that are aware of your Encodings to
- # avoid this translation. It's just too hard for me to support native
- # conversions in all of Ruby's Encodings.
- #
- # Anyway, the practical side of this is simple: make sure IO and String objects
- # passed into CSV have the proper Encoding set and everything should just work.
- # CSV methods that allow you to open IO objects (CSV::foreach(), CSV::open(),
- # CSV::read(), and CSV::readlines()) do allow you to specify the Encoding.
- #
- # One minor exception comes when generating CSV into a String with an Encoding
- # that is not ASCII compatible. There's no existing data for CSV to use to
- # prepare itself and thus you will probably need to manually specify the desired
- # Encoding for most of those cases. It will try to guess using the fields in a
- # row of output though, when using CSV::generate_line() or Array#to_csv().
- #
- # I try to point out any other Encoding issues in the documentation of methods
- # as they come up.
- #
- # This has been tested to the best of my ability with all non-"dummy" Encodings
- # Ruby ships with. However, it is brave new code and may have some bugs.
- # Please feel free to {report}[mailto:james@grayproductions.net] any issues you
- # find with it.
- #
- class CSV
- # The version of the installed library.
- VERSION = "2.4.7".freeze
- #
- # A CSV::Row is part Array and part Hash. It retains an order for the fields
- # and allows duplicates just as an Array would, but also allows you to access
- # fields by name just as you could if they were in a Hash.
- #
- # All rows returned by CSV will be constructed from this class, if header row
- # processing is activated.
- #
- class Row
- #
- # Construct a new CSV::Row from +headers+ and +fields+, which are expected
- # to be Arrays. If one Array is shorter than the other, it will be padded
- # with +nil+ objects.
- #
- # The optional +header_row+ parameter can be set to +true+ to indicate, via
- # CSV::Row.header_row?() and CSV::Row.field_row?(), that this is a header
- # row. Otherwise, the row is assumes to be a field row.
- #
- # A CSV::Row object supports the following Array methods through delegation:
- #
- # * empty?()
- # * length()
- # * size()
- #
- def initialize(headers, fields, header_row = false)
- @header_row = header_row
- # handle extra headers or fields
- @row = if headers.size > fields.size
- headers.zip(fields)
- else
- fields.zip(headers).map { |pair| pair.reverse }
- end
- end
- # Internal data format used to compare equality.
- attr_reader :row
- protected :row
- ### Array Delegation ###
- extend Forwardable
- def_delegators :@row, :empty?, :length, :size
- # Returns +true+ if this is a header row.
- def header_row?
- @header_row
- end
- # Returns +true+ if this is a field row.
- def field_row?
- not header_row?
- end
- # Returns the headers of this row.
- def headers
- @row.map { |pair| pair.first }
- end
- #
- # :call-seq:
- # field( header )
- # field( header, offset )
- # field( index )
- #
- # This method will fetch the field value by +header+ or +index+. If a field
- # is not found, +nil+ is returned.
- #
- # When provided, +offset+ ensures that a header match occurrs on or later
- # than the +offset+ index. You can use this to find duplicate headers,
- # without resorting to hard-coding exact indices.
- #
- def field(header_or_index, minimum_index = 0)
- # locate the pair
- finder = header_or_index.is_a?(Integer) ? :[] : :assoc
- pair = @row[minimum_index..-1].send(finder, header_or_index)
- # return the field if we have a pair
- pair.nil? ? nil : pair.last
- end
- alias_method :[], :field
- #
- # :call-seq:
- # []=( header, value )
- # []=( header, offset, value )
- # []=( index, value )
- #
- # Looks up the field by the semantics described in CSV::Row.field() and
- # assigns the +value+.
- #
- # Assigning past the end of the row with an index will set all pairs between
- # to <tt>[nil, nil]</tt>. Assigning to an unused header appends the new
- # pair.
- #
- def []=(*args)
- value = args.pop
- if args.first.is_a? Integer
- if @row[args.first].nil? # extending past the end with index
- @row[args.first] = [nil, value]
- @row.map! { |pair| pair.nil? ? [nil, nil] : pair }
- else # normal index assignment
- @row[args.first][1] = value
- end
- else
- index = index(*args)
- if index.nil? # appending a field
- self << [args.first, value]
- else # normal header assignment
- @row[index][1] = value
- end
- end
- end
- #
- # :call-seq:
- # <<( field )
- # <<( header_and_field_array )
- # <<( header_and_field_hash )
- #
- # If a two-element Array is provided, it is assumed to be a header and field
- # and the pair is appended. A Hash works the same way with the key being
- # the header and the value being the field. Anything else is assumed to be
- # a lone field which is appended with a +nil+ header.
- #
- # This method returns the row for chaining.
- #
- def <<(arg)
- if arg.is_a?(Array) and arg.size == 2 # appending a header and name
- @row << arg
- elsif arg.is_a?(Hash) # append header and name pairs
- arg.each { |pair| @row << pair }
- else # append field value
- @row << [nil, arg]
- end
- self # for chaining
- end
- #
- # A shortcut for appending multiple fields. Equivalent to:
- #
- # args.each { |arg| csv_row << arg }
- #
- # This method returns the row for chaining.
- #
- def push(*args)
- args.each { |arg| self << arg }
- self # for chaining
- end
- #
- # :call-seq:
- # delete( header )
- # delete( header, offset )
- # delete( index )
- #
- # Used to remove a pair from the row by +header+ or +index+. The pair is
- # located as described in CSV::Row.field(). The deleted pair is returned,
- # or +nil+ if a pair could not be found.
- #
- def delete(header_or_index, minimum_index = 0)
- if header_or_index.is_a? Integer # by index
- @row.delete_at(header_or_index)
- elsif i = index(header_or_index, minimum_index) # by header
- @row.delete_at(i)
- else
- [ ]
- end
- end
- #
- # The provided +block+ is passed a header and field for each pair in the row
- # and expected to return +true+ or +false+, depending on whether the pair
- # should be deleted.
- #
- # This method returns the row for chaining.
- #
- def delete_if(&block)
- @row.delete_if(&block)
- self # for chaining
- end
- #
- # This method accepts any number of arguments which can be headers, indices,
- # Ranges of either, or two-element Arrays containing a header and offset.
- # Each argument will be replaced with a field lookup as described in
- # CSV::Row.field().
- #
- # If called with no arguments, all fields are returned.
- #
- def fields(*headers_and_or_indices)
- if headers_and_or_indices.empty? # return all fields--no arguments
- @row.map { |pair| pair.last }
- else # or work like values_at()
- headers_and_or_indices.inject(Array.new) do |all, h_or_i|
- all + if h_or_i.is_a? Range
- index_begin = h_or_i.begin.is_a?(Integer) ? h_or_i.begin :
- index(h_or_i.begin)
- index_end = h_or_i.end.is_a?(Integer) ? h_or_i.end :
- index(h_or_i.end)
- new_range = h_or_i.exclude_end? ? (index_begin...index_end) :
- (index_begin..index_end)
- fields.values_at(new_range)
- else
- [field(*Array(h_or_i))]
- end
- end
- end
- end
- alias_method :values_at, :fields
- #
- # :call-seq:
- # index( header )
- # index( header, offset )
- #
- # This method will return the index of a field with the provided +header+.
- # The +offset+ can be used to locate duplicate header names, as described in
- # CSV::Row.field().
- #
- def index(header, minimum_index = 0)
- # find the pair
- index = headers[minimum_index..-1].index(header)
- # return the index at the right offset, if we found one
- index.nil? ? nil : index + minimum_index
- end
- # Returns +true+ if +name+ is a header for this row, and +false+ otherwise.
- def header?(name)
- headers.include? name
- end
- alias_method :include?, :header?
- #
- # Returns +true+ if +data+ matches a field in this row, and +false+
- # otherwise.
- #
- def field?(data)
- fields.include? data
- end
- include Enumerable
- #
- # Yields each pair of the row as header and field tuples (much like
- # iterating over a Hash).
- #
- # Support for Enumerable.
- #
- # This method returns the row for chaining.
- #
- def each(&block)
- @row.each(&block)
- self # for chaining
- end
- #
- # Returns +true+ if this row contains the same headers and fields in the
- # same order as +other+.
- #
- def ==(other)
- @row == other.row
- end
- #
- # Collapses the row into a simple Hash. Be warning that this discards field
- # order and clobbers duplicate fields.
- #
- def to_hash
- # flatten just one level of the internal Array
- Hash[*@row.inject(Array.new) { |ary, pair| ary.push(*pair) }]
- end
- #
- # Returns the row as a CSV String. Headers are not used. Equivalent to:
- #
- # csv_row.fields.to_csv( options )
- #
- def to_csv(options = Hash.new)
- fields.to_csv(options)
- end
- alias_method :to_s, :to_csv
- # A summary of fields, by header, in an ASCII compatible String.
- def inspect
- str = ["#<", self.class.to_s]
- each do |header, field|
- str << " " << (header.is_a?(Symbol) ? header.to_s : header.inspect) <<
- ":" << field.inspect
- end
- str << ">"
- begin
- str.join
- rescue # any encoding error
- str.map do |s|
- e = Encoding::Converter.asciicompat_encoding(s.encoding)
- e ? s.encode(e) : s.force_encoding("ASCII-8BIT")
- end.join
- end
- end
- end
- #
- # A CSV::Table is a two-dimensional data structure for representing CSV
- # documents. Tables allow you to work with the data by row or column,
- # manipulate the data, and even convert the results back to CSV, if needed.
- #
- # All tables returned by CSV will be constructed from this class, if header
- # row processing is activated.
- #
- class Table
- #
- # Construct a new CSV::Table from +array_of_rows+, which are expected
- # to be CSV::Row objects. All rows are assumed to have the same headers.
- #
- # A CSV::Table object supports the following Array methods through
- # delegation:
- #
- # * empty?()
- # * length()
- # * size()
- #
- def initialize(array_of_rows)
- @table = array_of_rows
- @mode = :col_or_row
- end
- # The current access mode for indexing and iteration.
- attr_reader :mode
- # Internal data format used to compare equality.
- attr_reader :table
- protected :table
- ### Array Delegation ###
- extend Forwardable
- def_delegators :@table, :empty?, :length, :size
- #
- # Returns a duplicate table object, in column mode. This is handy for
- # chaining in a single call without changing the table mode, but be aware
- # that this method can consume a fair amount of memory for bigger data sets.
- #
- # This method returns the duplicate table for chaining. Don't chain
- # destructive methods (like []=()) this way though, since you are working
- # with a duplicate.
- #
- def by_col
- self.class.new(@table.dup).by_col!
- end
- #
- # Switches the mode of this table to column mode. All calls to indexing and
- # iteration methods will work with columns until the mode is changed again.
- #
- # This method returns the table and is safe to chain.
- #
- def by_col!
- @mode = :col
- self
- end
- #
- # Returns a duplicate table object, in mixed mode. This is handy for
- # chaining in a single call without changing the table mode, but be aware
- # that this method can consume a fair amount of memory for bigger data sets.
- #
- # This method returns the duplicate table for chaining. Don't chain
- # destructive methods (like []=()) this way though, since you are working
- # with a duplicate.
- #
- def by_col_or_row
- self.class.new(@table.dup).by_col_or_row!
- end
- #
- # Switches the mode of this table to mixed mode. All calls to indexing and
- # iteration methods will use the default intelligent indexing system until
- # the mode is changed again. In mixed mode an index is assumed to be a row
- # reference while anything else is assumed to be column access by headers.
- #
- # This method returns the table and is safe to chain.
- #
- def by_col_or_row!
- @mode = :col_or_row
- self
- end
- #
- # Returns a duplicate table object, in row mode. This is handy for chaining
- # in a single call without changing the table mode, but be aware that this
- # method can consume a fair amount of memory for bigger data sets.
- #
- # This method returns the duplicate table for chaining. Don't chain
- # destructive methods (like []=()) this way though, since you are working
- # with a duplicate.
- #
- def by_row
- self.class.new(@table.dup).by_row!
- end
- #
- # Switches the mode of this table to row mode. All calls to indexing and
- # iteration methods will work with rows until the mode is changed again.
- #
- # This method returns the table and is safe to chain.
- #
- def by_row!
- @mode = :row
- self
- end
- #
- # Returns the headers for the first row of this table (assumed to match all
- # other rows). An empty Array is returned for empty tables.
- #
- def headers
- if @table.empty?
- Array.new
- else
- @table.first.headers
- end
- end
- #
- # In the default mixed mode, this method returns rows for index access and
- # columns for header access. You can force the index association by first
- # calling by_col!() or by_row!().
- #
- # Columns are returned as an Array of values. Altering that Array has no
- # effect on the table.
- #
- def [](index_or_header)
- if @mode == :row or # by index
- (@mode == :col_or_row and index_or_header.is_a? Integer)
- @table[index_or_header]
- else # by header
- @table.map { |row| row[index_or_header] }
- end
- end
- #
- # In the default mixed mode, this method assigns rows for index access and
- # columns for header access. You can force the index association by first
- # calling by_col!() or by_row!().
- #
- # Rows may be set to an Array of values (which will inherit the table's
- # headers()) or a CSV::Row.
- #
- # Columns may be set to a single value, which is copied to each row of the
- # column, or an Array of values. Arrays of values are assigned to rows top
- # to bottom in row major order. Excess values are ignored and if the Array
- # does not have a value for each row the extra rows will receive a +nil+.
- #
- # Assigning to an existing column or row clobbers the data. Assigning to
- # new columns creates them at the right end of the table.
- #
- def []=(index_or_header, value)
- if @mode == :row or # by index
- (@mode == :col_or_row and index_or_header.is_a? Integer)
- if value.is_a? Array
- @table[index_or_header] = Row.new(headers, value)
- else
- @table[index_or_header] = value
- end
- else # set column
- if value.is_a? Array # multiple values
- @table.each_with_index do |row, i|
- if row.header_row?
- row[index_or_header] = index_or_header
- else
- row[index_or_header] = value[i]
- end
- end
- else # repeated value
- @table.each do |row|
- if row.header_row?
- row[index_or_header] = index_or_header
- else
- row[index_or_header] = value
- end
- end
- end
- end
- end
- #
- # The mixed mode default is to treat a list of indices as row access,
- # returning the rows indicated. Anything else is considered columnar
- # access. For columnar access, the return set has an Array for each row
- # with the values indicated by the headers in each Array. You can force
- # column or row mode using by_col!() or by_row!().
- #
- # You cannot mix column and row access.
- #
- def values_at(*indices_or_headers)
- if @mode == :row or # by indices
- ( @mode == :col_or_row and indices_or_headers.all? do |index|
- index.is_a?(Integer) or
- ( index.is_a?(Range) and
- index.first.is_a?(Integer) and
- index.last.is_a?(Integer) )
- end )
- @table.values_at(*indices_or_headers)
- else # by headers
- @table.map { |row| row.values_at(*indices_or_headers) }
- end
- end
- #
- # Adds a new row to the bottom end of this table. You can provide an Array,
- # which will be converted to a CSV::Row (inheriting the table's headers()),
- # or a CSV::Row.
- #
- # This method returns the table for chaining.
- #
- def <<(row_or_array)
- if row_or_array.is_a? Array # append Array
- @table << Row.new(headers, row_or_array)
- else # append Row
- @table << row_or_array
- end
- self # for chaining
- end
- #
- # A shortcut for appending multiple rows. Equivalent to:
- #
- # rows.each { |row| self << row }
- #
- # This method returns the table for chaining.
- #
- def push(*rows)
- rows.each { |row| self << row }
- self # for chaining
- end
- #
- # Removes and returns the indicated column or row. In the default mixed
- # mode indices refer to rows and everything else is assumed to be a column
- # header. Use by_col!() or by_row!() to force the lookup.
- #
- def delete(index_or_header)
- if @mode == :row or # by index
- (@mode == :col_or_row and index_or_header.is_a? Integer)
- @table.delete_at(index_or_header)
- else # by header
- @table.map { |row| row.delete(index_or_header).last }
- end
- end
- #
- # Removes any column or row for which the block returns +true+. In the
- # default mixed mode or row mode, iteration is the standard row major
- # walking of rows. In column mode, interation will +yield+ two element
- # tuples containing the column name and an Array of values for that column.
- #
- # This method returns the table for chaining.
- #
- def delete_if(&block)
- if @mode == :row or @mode == :col_or_row # by index
- @table.delete_if(&block)
- else # by header
- to_delete = Array.new
- headers.each_with_index do |header, i|
- to_delete << header if block[[header, self[header]]]
- end
- to_delete.map { |header| delete(header) }
- end
- self # for chaining
- end
- include Enumerable
- #
- # In the default mixed mode or row mode, iteration is the standard row major
- # walking of rows. In column mode, interation will +yield+ two element
- # tuples containing the column name and an Array of values for that column.
- #
- # This method returns the table for chaining.
- #
- def each(&block)
- if @mode == :col
- headers.each { |header| block[[header, self[header]]] }
- else
- @table.each(&block)
- end
- self # for chaining
- end
- # Returns +true+ if all rows of this table ==() +other+'s rows.
- def ==(other)
- @table == other.table
- end
- #
- # Returns the table as an Array of Arrays. Headers will be the first row,
- # then all of the field rows will follow.
- #
- def to_a
- @table.inject([headers]) do |array, row|
- if row.header_row?
- array
- else
- array + [row.fields]
- end
- end
- end
- #
- # Returns the table as a complete CSV String. Headers will be listed first,
- # then all of the field rows.
- #
- # This method assumes you want the Table.headers(), unless you explicitly
- # pass <tt>:write_headers => false</tt>.
- #
- def to_csv(options = Hash.new)
- wh = options.fetch(:write_headers, true)
- @table.inject(wh ? [headers.to_csv(options)] : [ ]) do |rows, row|
- if row.header_row?
- rows
- else
- rows + [row.fields.to_csv(options)]
- end
- end.join
- end
- alias_method :to_s, :to_csv
- # Shows the mode and size of this table in a US-ASCII String.
- def inspect
- "#<#{self.class} mode:#{@mode} row_count:#{to_a.size}>".encode("US-ASCII")
- end
- end
- # The error thrown when the parser encounters illegal CSV formatting.
- class MalformedCSVError < RuntimeError; end
- #
- # A FieldInfo Struct contains details about a field's position in the data
- # source it was read from. CSV will pass this Struct to some blocks that make
- # decisions based on field structure. See CSV.convert_fields() for an
- # example.
- #
- # <b><tt>index</tt></b>:: The zero-based index of the field in its row.
- # <b><tt>line</tt></b>:: The line of the data source this row is from.
- # <b><tt>header</tt></b>:: The header for the column, when available.
- #
- FieldInfo = Struct.new(:index, :line, :header)
- # A Regexp used to find and convert some common Date formats.
- DateMatcher = / \A(?: (\w+,?\s+)?\w+\s+\d{1,2},?\s+\d{2,4} |
- \d{4}-\d{2}-\d{2} )\z /x
- # A Regexp used to find and convert some common DateTime formats.
- DateTimeMatcher =
- / \A(?: (\w+,?\s+)?\w+\s+\d{1,2}\s+\d{1,2}:\d{1,2}:\d{1,2},?\s+\d{2,4} |
- \d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2} )\z /x
- # The encoding used by all converters.
- ConverterEncoding = Encoding.find("UTF-8")
- #
- # This Hash holds the built-in converters of CSV that can be accessed by name.
- # You can select Converters with CSV.convert() or through the +options+ Hash
- # passed to CSV::new().
- #
- # <b><tt>:integer</tt></b>:: Converts any field Integer() accepts.
- # <b><tt>:float</tt></b>:: Converts any field Float() accepts.
- # <b><tt>:numeric</tt></b>:: A combination of <tt>:integer</tt>
- # and <tt>:float</tt>.
- # <b><tt>:date</tt></b>:: Converts any field Date::parse() accepts.
- # <b><tt>:date_time</tt></b>:: Converts any field DateTime::parse() accepts.
- # <b><tt>:all</tt></b>:: All built-in converters. A combination of
- # <tt>:date_time</tt> and <tt>:numeric</tt>.
- #
- # All built-in converters transcode field data to UTF-8 before attempting a
- # conversion. If your data cannot be transcoded to UTF-8 the conversion will
- # fail and the field will remain unchanged.
- #
- # This Hash is intentionally left unfrozen and users should feel free to add
- # values to it that can be accessed by all CSV objects.
- #
- # To add a combo field, the value should be an Array of names. Combo fields
- # can be nested with other combo fields.
- #
- Converters = { integer: lambda { |f|
- Integer(f.encode(ConverterEncoding)) rescue f
- },
- float: lambda { |f|
- Float(f.encode(ConverterEncoding)) rescue f
- },
- numeric: [:integer, :float],
- date: lambda { |f|
- begin
- e = f.encode(ConverterEncoding)
- e =~ DateMatcher ? Date.parse(e) : f
- rescue # encoding conversion or date parse errors
- f
- end
- },
- date_time: lambda { |f|
- begin
- e = f.encode(ConverterEncoding)
- e =~ DateTimeMatcher ? DateTime.parse(e) : f
- rescue # encoding conversion or date parse errors
- f
- end
- },
- all: [:date_time, :numeric] }
- #
- # This Hash holds the built-in header converters of CSV that can be accessed
- # by name. You can select HeaderConverters with CSV.header_convert() or
- # through the +options+ Hash passed to CSV::new().
- #
- # <b><tt>:downcase</tt></b>:: Calls downcase() on the header String.
- # <b><tt>:symbol</tt></b>:: The header String is downcased, spaces are
- # replaced with underscores, non-word characters
- # are dropped, and finally to_sym() is called.
- #
- # All built-in header converters transcode header data to UTF-8 before
- # attempting a conversion. If your data cannot be transcoded to UTF-8 the
- # conversion will fail and the header will remain unchanged.
- #
- # This Hash is intetionally left unfrozen and users should feel free to add
- # values to it that can be accessed by all CSV objects.
- #
- # To add a combo field, the value should be an Array of names. Combo fields
- # can be nested with other combo fields.
- #
- HeaderConverters = {
- downcase: lambda { |h| h.encode(ConverterEncoding).downcase },
- symbol: lambda { |h|
- h.encode(ConverterEncoding).downcase.gsub(/\s+/, "_").
- gsub(/\W+/, "").to_sym
- }
- }
- #
- # The options used when no overrides are given by calling code. They are:
- #
- # <b><tt>:col_sep</tt></b>:: <tt>","</tt>
- # <b><tt>:row_sep</tt></b>:: <tt>:auto</tt>
- # <b><tt>:quote_char</tt></b>:: <tt>'"'</tt>
- # <b><tt>:field_size_limit</tt></b>:: +nil+
- # <b><tt>:converters</tt></b>:: +nil+
- # <b><tt>:unconverted_fields</tt></b>:: +nil+
- # <b><tt>:headers</tt></b>:: +false+
- # <b><tt>:return_headers</tt></b>:: +false+
- # <b><tt>:header_converters</tt></b>:: +nil+
- # <b><tt>:skip_blanks</tt></b>:: +false+
- # <b><tt>:force_quotes</tt></b>:: +false+
- #
- DEFAULT_OPTIONS = { col_sep: ",",
- row_sep: :auto,
- quote_char: '"',
- field_size_limit: nil,
- converters: nil,
- unconverted_fields: nil,
- headers: false,
- return_headers: false,
- header_converters: nil,
- skip_blanks: false,
- force_quotes: false }.freeze
- #
- # This method will return a CSV instance, just like CSV::new(), but the
- # instance will be cached and returned for all future calls to this method for
- # the same +data+ object (tested by Object#object_id()) with the same
- # +options+.
- #
- # If a block is given, the instance is passed to the block and the return
- # value becomes the return value of the block.
- #
- def self.instance(data = $stdout, options = Hash.new)
- # create a _signature_ for this method call, data object and options
- sig = [data.object_id] +
- options.values_at(*DEFAULT_OPTIONS.keys.sort_by { |sym| sym.to_s })
- # fetch or create the instance for this signature
- @@instances ||= Hash.new
- instance = (@@instances[sig] ||= new(data, options))
- if block_given?
- yield instance # run block, if given, returning result
- else
- instance # or return the instance
- end
- end
- #
- # This method allows you to serialize an Array of Ruby objects to a String or
- # File of CSV data. This is not as powerful as Marshal or YAML, but perhaps
- # useful for spreadsheet and database interaction.
- #
- # Out of the box, this method is intended to work with simple data objects or
- # Structs. It will serialize a list of instance variables and/or
- # Struct.members().
- #
- # If you need need more complicated serialization, you can control the process
- # by adding methods to the class to be serialized.
- #
- # A class method csv_meta() is responsible for returning the first row of the
- # document (as an Array). This row is considered to be a Hash of the form
- # key_1,value_1,key_2,value_2,... CSV::load() expects to find a class key
- # with a value of the stringified class name and CSV::dump() will create this,
- # if you do not define this method. This method is only called on the first
- # object of the Array.
- #
- # The next method you can provide is an instance method called csv_headers().
- # This method is expected to return the second line of the document (again as
- # an Array), which is to be used to give each column a header. By default,
- # CSV::load() will set an instance variable if the field header starts with an
- # @ character or call send() passing the header as the method name and
- # the field value as an argument. This method is only called on the first
- # object of the Array.
- #
- # Finally, you can provide an instance method called csv_dump(), which will
- # be passed the headers. This should return an Array of fields that can be
- # serialized for this object. This method is called once for every object in
- # the Array.
- #
- # The +io+ parameter can be used to serialize to a File, and +options+ can be
- # anything CSV::new() accepts.
- #
- def self.dump(ary_of_objs, io = "", options = Hash.new)
- obj_template = ary_of_objs.first
- csv = new(io, options)
- # write meta information
- begin
- csv << obj_template.class.csv_meta
- rescue NoMethodError
- csv << [:class, obj_template.class]
- end
- # write headers
- begin
- headers = obj_template.csv_headers
- rescue NoMethodError
- headers = obj_template.instance_variables.sort
- if obj_template.class.ancestors.find { |cls| cls.to_s =~ /\AStruct\b/ }
- headers += obj_template.members.map { |mem| "#{mem}=" }.sort
- end
- end
- csv << headers
- # serialize each object
- ary_of_objs.each do |obj|
- begin
- csv << obj.csv_dump(headers)
- rescue NoMethodError
- csv << headers.map do |var|
- if var[0] == ?@
- obj.instance_variable_get(var)
- else
- obj[var[0..-2]]
- end
- end
- end
- end
- if io.is_a? String
- csv.string
- else
- csv.close
- end
- end
- #
- # This method is the reading counterpart to CSV::dump(). See that method for
- # a detailed description of the process.
- #
- # You can customize loading by adding a class method called csv_load() which
- # will be passed a Hash of meta information, an Array of headers, and an Array
- # of fields for the object the method is expected to return.
- #
- # Remember that all fields will be Strings after this load. If you need
- # something else, use +options+ to setup converters or provide a custom
- # csv_load() implementation.
- #
- def self.load(io_or_str, options = Hash.new)
- csv = new(io_or_str, options)
- # load meta information
- meta = Hash[*csv.shift]
- cls = meta["class".encode(csv.encoding)].split("::".encode(csv.encoding)).
- inject(Object) do |c, const|
- c.const_get(const)
- end
- # load headers
- headers = csv.shift
- # unserialize each object stored in the file
- results = csv.inject(Array.new) do |all, row|
- begin
- obj = cls.csv_load(meta, headers, row)
- rescue NoMethodError
- obj = cls.allocate
- headers.zip(row) do |name, value|
- if name[0] == ?@
- obj.instance_variable_set(name, value)
- else
- obj.send(name, value)
- end
- end
- end
- all << obj
- end
- csv.close unless io_or_str.is_a? String
- results
- end
- #
- # :call-seq:
- # filter( options = Hash.new ) { |row| ... }
- # filter( input, options = Hash.new ) { |row| ... }
- # filter( input, output, options = Hash.new ) { |row| ... }
- #
- # This method is a convenience for building Unix-like filters for CSV data.
- # Each row is yielded to the provided block which can alter it as needed.
- # After the block returns, the row is appended to +output+ altered or not.
- #
- # The +input+ and +output+ arguments can be anything CSV::new() accepts
- # (generally String or IO objects). If not given, they default to
- # <tt>ARGF</tt> and <tt>$stdout</tt>.
- #
- # The +options+ parameter is also filtered down to CSV::new() after some
- # clever key parsing. Any key beginning with <tt>:in_</tt> or
- # <tt>:input_</tt> will have that leading identifier stripped and will only
- # be used in the +options+ Hash for the +input+ object. Keys starting with
- # <tt>:out_</tt> or <tt>:output_</tt> affect only +output+. All other keys
- # are assigned to both objects.
- #
- # The <tt>:output_row_sep</tt> +option+ defaults to
- # <tt>$INPUT_RECORD_SEPARATOR</tt> (<tt>$/</tt>).
- #
- def self.filter(*args)
- # parse options for input, output, or both
- in_options, out_options = Hash.new, {row_sep: $INPUT_RECORD_SEPARATOR}
- if args.last.is_a? Hash
- args.pop.each do |key, value|
- case key.to_s
- when /\Ain(?:put)?_(.+)\Z/
- in_options[$1.to_sym] = value
- when /\Aout(?:put)?_(.+)\Z/
- out_options[$1.to_sym] = value
- else
- in_options[key] = value
- out_options[key] = value
- end
- end
- end
- # build input and output wrappers
- input = new(args.shift || ARGF, in_options)
- output = new(args.shift || $stdout, out_options)
- # read, yield, write
- input.each do |row|
- yield row
- output << row
- end
- end
- #
- # This method is intended as the primary interface for reading CSV files. You
- # pass a +path+ and any +options+ you wish to set for the read. Each row of
- # file will be passed to the provided +block+ in turn.
- #
- # The +options+ parameter can be anything CSV::new() understands. This method
- # also understands an additional <tt>:encoding</tt> parameter that you can use
- # to specify the Encoding of the data in the file to be read. You must provide
- # this unless your data is in Encoding::default_external(). CSV will use this
- # to deterime how to parse the data. You may provide a second Encoding to
- # have the data transcoded as it is read. For example,
- # <tt>encoding: "UTF-32BE:UTF-8"</tt> would read UTF-32BE data from the file
- # but transcode it to UTF-8 before CSV parses it.
- #
- def self.foreach(path, options = Hash.new, &block)
- encoding = options.delete(:encoding)
- mode = "rb"
- mode << ":#{encoding}" if encoding
- open(path, mode, options) do |csv|
- csv.each(&block)
- end
- end
- #
- # :call-seq:
- # generate( str, options = Hash.new ) { |csv| ... }
- # generate( options = Hash.new ) { |csv| ... }
- #
- # This method wraps a String you provide, or an empty default String, in a
- # CSV object which is passed to the provided block. You can use the block to
- # append CSV rows to the String and when the block exits, the final String
- # will be returned.
- #
- # Note that a passed String *is* modfied by this method. Call dup() before
- # passing if you need a new String.
- #
- # The +options+ parameter can be anything CSV::new() understands. This method
- # understands an additional <tt>:encoding</tt> parameter when not passed a
- # String to set the base Encoding for the output. CSV needs this hint if you
- # plan to output non-ASCII compatible data.
- #
- def self.generate(*args)
- # add a default empty String, if none was given
- if args.first.is_a? String
- io = StringIO.new(args.shift)
- io.seek(0, IO::SEEK_END)
- args.unshift(io)
- else
- encoding = args.last.is_a?(Hash) ? args.last.delete(:encoding) : nil
- str = ""
- str.encode!(encoding) if encoding
- args.unshift(str)
- end
- csv = new(*args) # wrap
- yield csv # yield for appending
- csv.string # return final String
- end
- #
- # This method is a shortcut for converting a single row (Array) into a CSV
- # String.
- #
- # The +options+ parameter can be anything CSV::new() understands. This method
- # understands an additional <tt>:encoding</tt> parameter to set the base
- # Encoding for the output. This method will try to guess your Encoding from
- # the first non-+nil+ field in +row+, if possible, but you may need to use
- # this parameter as a backup plan.
- #
- # The <tt>:row_sep</tt> +option+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>
- # (<tt>$/</tt>) when calling this method.
- #
- def self.generate_line(row, options = Hash.new)
- options = {row_sep: $INPUT_RECORD_SEPARATOR}.merge(options)
- encoding = options.delete(:encoding)
- str = ""
- if encoding
- str.force_encoding(encoding)
- elsif field = row.find { |f| not f.nil? }
- str.force_encoding(String(field).encoding)
- end
- (new(str, options) << row).string
- end
- #
- # :call-seq:
- # open( filename, mode = "rb", options = Hash.new ) { |faster_csv| ... }
- # open( filename, options = Hash.new ) { |faster_csv| ... }
- # open( filename, mode = "rb", options = Hash.new )
- # open( filename, options = Hash.new )
- #
- # This method opens an IO object, and wraps that with CSV. This is intended
- # as the primary interface for writing a CSV file.
- #
- # You must pass a +filename+ and may optionally add a +mode+ for Ruby's
- # open(). You may also pass an optional Hash containing any +options+
- # CSV::new() understands as the final argument.
- #
- # This method works like Ruby's open() call, in that it will pass a CSV object
- # to a provided block and close it when the block terminates, or it will
- # return the CSV object when no block is provided. (*Note*: This is different
- # from the Ruby 1.8 CSV library which passed rows to the block. Use
- # CSV::foreach() for that behavior.)
- #
- # You must provide a +mode+ with an embedded Encoding designator unless your
- # data is in Encoding::default_external(). CSV will check the Encoding of the
- # underlying IO object (set by the +mode+ you pass) to deterime how to parse
- # the data. You may provide a second Encoding to have the data transcoded as
- # it is read just as you can with a normal call to IO::open(). For example,
- # <tt>"rb:UTF-32BE:UTF-8"</tt> would read UTF-32BE data from the file but
- # transcode it to UTF-8 before CSV parses it.
- #
- # An opened CSV object will delegate to many IO methods for convenience. You
- # may call:
- #
- # * binmode()
- # * binmode?()
- # * close()
- # * close_read()
- # * close_write()
- # * closed?()
- # * eof()
- # * eof?()
- # * external_encoding()
- # * fcntl()
- # * fileno()
- # * flock()
- # * flush()
- # * fsync()
- # * internal_encoding()
- # * ioctl()
- # * isatty()
- # * path()
- # * pid()
- # * pos()
- # * pos=()
- # * reopen()
- # * seek()
- # * stat()
- # * sync()
- # * sync=()
- # * tell()
- # * to_i()
- # * to_io()
- # * truncate()
- # * tty?()
- #
- def self.open(*args)
- # find the +options+ Hash
- options = if args.last.is_a? Hash then args.pop else Hash.new end
- # default to a binary open mode
- args << "rb" if args.size == 1
- # wrap a File opened with the remaining +args+
- csv = new(File.open(*args), options)
- # handle blocks like Ruby's open(), not like the CSV library
- if block_given?
- begin
- yield csv
- ensure
- csv.close
- end
- else
- csv
- end
- end
- #
- # :call-seq:
- # parse( str, options = Hash.new ) { |row| ... }
- # parse( str, options = Hash.new )
- #
- # This method can be used to easily parse CSV out of a String. You may either
- # provide a +block+ which will be called with each row of the String in turn,
- # or just use the returned Array of Arrays (when no +block+ is given).
- #
- # You pass your +str+ to read from, and an optional +options+ Hash containing
- # anything CSV::new() understands.
- #
- def self.parse(*args, &block)
- csv = new(*args)
- if block.nil? # slurp contents, if no block is given
- begin
- csv.read
- ensure
- csv.close
- end
- else # or pass each row to a provided block
- csv.each(&block)
- end
- end
- #
- # This method is a shortcut for converting a single line of a CSV String into
- # a into an Array. Note that if +line+ contains multiple rows, anything
- # beyond the first row is ignored.
- #
- # The +options+ parameter can be anything CSV::new() understands.
- #
- def self.parse_line(line, options = Hash.new)
- new(line, options).shift
- end
- #
- # Use to slurp a CSV file into an Array of Arrays. Pass the +path+ to the
- # file and any +options+ CSV::new() understands. This method also understands
- # an additional <tt>:encoding</tt> parameter that you can use to specify the
- # Encoding of the data in the file to be read. You must provide this unless
- # your data is in Encoding::default_external(). CSV will use this to deterime
- # how to parse the data. You may provide a second Encoding to have the data
- # transcoded as it is read. For example,
- # <tt>encoding: "UTF-32BE:UTF-8"</tt> would read UTF-32BE data from the file
- # but transcode it to UTF-8 before CSV parses it.
- #
- def self.read(path, options = Hash.new)
- encoding = options.delete(:encoding)
- mode = "rb"
- mode << ":#{encoding}" if encoding
- open(path, mode, options) { |csv| csv.read }
- end
- # Alias for CSV::read().
- def self.readlines(*args)
- read(*args)
- end
- #
- # A shortcut for:
- #
- # CSV.read( path, { headers: true,
- # converters: :numeric,
- # header_converters: :symbol }.merge(options) )
- #
- def self.table(path, options = Hash.new)
- read( path, { headers: true,
- converters: :numeric,
- header_converters: :symbol }.merge(options) )
- end
- #
- # This constructor will wrap either a String or IO object passed in +data+ for
- # reading and/or writing. In addition to the CSV instance methods, several IO
- # methods are delegated. (See CSV::open() for a complete list.) If you pass
- # a String for +data+, you can later retrieve it (after writing to it, for
- # example) with CSV.string().
- #
- # Note that a wrapped String will be positioned at at the beginning (for
- # reading). If you want it at the end (for writing), use CSV::generate().
- # If you want any other positioning, pass a preset StringIO object instead.
- #
- # You may set any reading and/or writing preferences in the +options+ Hash.
- # Available options are:
- #
- # <b><tt>:col_sep</tt></b>:: The String placed between each field.
- # This String will be transcoded into
- # the data's Encoding before parsing.
- # <b><tt>:row_sep</tt></b>:: The String appended to the end of each
- # row. This can be set to the special
- # <tt>:auto</tt> setting, which req…
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