Class: ValuesReader

Inherits:

Object

• Object
• ValuesReader

Includes:

LogUtils::Logging, TextUtils::ValueHelper

Defined in:

lib/textutils/reader/values_reader.rb

Instance Method Summary

• #each_line ⇒ Object

  support multi line records.

• #find_values(line) ⇒ Object

  todo: move to helper for reuse a la find_key_n_title ??? use different/better name ?? e.g.

• #initialize(path, more_attribs = {}) ⇒ ValuesReader constructor

  A new instance of ValuesReader.

Methods included from TextUtils::ValueHelper

#find_grade, #find_key_n_title, #is_address?, #is_region?, #is_taglist?, #is_website?, #is_year?, #match_abv, #match_brewery, #match_city, #match_country, #match_hl, #match_kcal, #match_km_squared, #match_metro, #match_metro_flag, #match_metro_pop, #match_number, #match_og, #match_region_for_country, #match_supra, #match_supra_flag, #match_website, #match_year

Constructor Details

#initialize(path, more_attribs = {}) ⇒ ValuesReader

Returns a new instance of ValuesReader.

# File 'lib/textutils/reader/values_reader.rb', line 60

def initialize( path, more_attribs={} )
  @more_attribs = more_attribs

  ### workaround/hack
  #  if path includes newline assume it's a string buffer not a file name
  #  fix: use  from_file an from_string etc. for  ctor
  #   check  what is the best convention (follow  ???)

  if path =~ /\n/m
    @path = 'stringio'   # what name to use ???
    @data = path.dup   # make a duplicate ?? why? why not?
  else
    @path = path
    @data = File.read_utf8( @path )
  end
end

Instance Method Details

#each_line ⇒ Object

support multi line records

# File 'lib/textutils/reader/values_reader.rb', line 86

def each_line   # support multi line records

  inside_record  = false
  blank_counter  = 0    # count of number of blank lines (note: 1+ blank lines clear multi-line record)
  values         = []

  @data.each_line do |line|

    ## allow alternative comment lines
    ## e.g. -- comment or
    ##      % comment
    ##  why?  # might get used by markdown for marking headers, for example

    ## NB: for now alternative comment lines not allowed as end of line style e.g
    ##  some data, more data   -- comment here

    if line =~ /^\s*#/  ||
       line =~ /^\s*--/ ||
       line =~ /^\s*%/  ||
       line =~ /^\s*__/
      # skip komments and do NOT copy to result (keep comments secret!)
      logger.debug 'skipping comment line'
      next
    end

    if line =~ /^\s*$/
      # kommentar oder leerzeile überspringen 
      blank_counter += 1
      logger.debug "skipping blank line (#{blank_counter})"
      next
    end

    # pass 1) remove possible trailing eol comment
    ##  e.g    -> nyc, New York   # Sample EOL Comment Here (with or without commas,,,,)
    ## becomes -> nyc, New York

    line = line.sub( /\s+#.+$/, '' )

    # pass 2) remove leading and trailing whitespace
    
    line = line.strip


    if line =~ /^-\s/   # check for group headers  e.g.  - St. James Brewery
      logger.info "  skip group header #{line} for now (fix/add soon)"
      next
    elsif line =~ /^\[([a-z][a-z]+)\]/
    ### check for multiline record
    ##    must start with key e.g. [guiness]
    ##   for now only supports key with letter a-z (no digits/numbers or underscore or dots)
 
      if values.length > 0  # check if we already processed a record? if yes; yield last record (before reset)
        attribs, more_values = find_key_n_title( values )
        attribs = attribs.merge( @more_attribs )  # e.g. merge country_id and other defaults if present
        yield( attribs, more_values )
        values         = []
      end

      inside_record  = true
      blank_counter  = 0

      # NB: every additional line is one value e.g. city:wien, etc.
      #  allows you to use any chars
      logger.debug "   multi-line record w/ key »#{$1}«"

      values         = [$1.dup]    # add key as first value in ary
    elsif inside_record && blank_counter == 0 && line =~ /\/{2}/ # check address line (must contain //)
      values += [line.dup]     # assume single value column (no need to escape commas)
    elsif inside_record && blank_counter == 0 && line =~ /^[a-z][a-z0-9.]*[a-z0-9]:/ # check key: value pair
      values += [line.dup]     # assume single value column (no need to escape commas)
    else
      if inside_record && blank_counter == 0   # continue adding more values
        values += find_values( line )
      else                                     # assume single-line (stand-alone / classic csv) record          
        if values.length > 0
          attribs, more_values = find_key_n_title( values )
          attribs = attribs.merge( @more_attribs )  # e.g. merge country_id and other defaults if present
          yield( attribs, more_values )
          values         = []
        end
        inside_record  = false
        blank_counter  = 0
        values = find_values( line )
      end
    end

  end # each lines

  # do NOT forget to yield last line (if present/processed)
  if values.length > 0
    attribs, more_values = find_key_n_title( values )
    attribs = attribs.merge( @more_attribs )  # e.g. merge country_id and other defaults if present
    yield( attribs, more_values )
  end

end

#find_values(line) ⇒ Object

todo:

 move to helper for reuse a la find_key_n_title ???  
use different/better name ?? e.g. find_values_in_line  or split_line_into_values ??

# File 'lib/textutils/reader/values_reader.rb', line 187

def find_values( line )
  ## note returns an array of values (strings)

  meta_comma     = '«KOMMA»'
  meta_separator = '« »'

  # guard escaped commas
  #  e.g. convert \, to «KOMMA»
  line = line.gsub( '\,', meta_comma )

  # note: use generic separator (allow us to configure separator)
  #  e.g « »
  line = line.gsub( ',', meta_separator )

  # restore escaped commas (before split)
  line = line.gsub( meta_comma, ',' )

  logger.debug "line: |»#{line}«|"

  values = line.split( meta_separator )

  # pass 1) remove leading and trailing whitespace for values

  values = values.map { |value| value.strip }


  ##### todo/fix:
  #  !!!REMOVE!!!
  # remove support of comment column? (NB: must NOT include commas)
  # pass 2) remove comment columns
  #
  #  todo/fix: check if still possible ?? - add an example here how it looks like/works

  values = values.select do |value|
    if value =~ /^#/  ## start with # treat it as a comment column; e.g. remove it
      logger.info "   removing column with value »#{value}«"
      false
    else
      true
    end
  end

  logger.debug "  values: |»#{values.join('« »')}«|"
  values
end