Class: CsvHashReader

Inherits:
Object
  • Object
show all
Extended by:
Forwardable
Includes:
Enumerable
Defined in:
lib/csvreader/base.rb,
lib/csvreader/builder.rb,
lib/csvreader/reader_hash.rb

Defined Under Namespace

Classes: Builder

Constant Summary collapse

DEFAULT =

pre-define CsvReader (built-in) formats/dialect

Builder.new( Parser::DEFAULT )
NUMERIC = 
Builder.new( Parser::NUMERIC )
STRICT = 
Builder.new( Parser::STRICT )
RFC4180 = 
Builder.new( Parser::RFC4180 )
EXCEL = 
Builder.new( Parser::EXCEL )
MYSQL = 
Builder.new( Parser::MYSQL )
POSTGRES = 
POSTGRESQL           = Builder.new( Parser::POSTGRESQL )
POSTGRES_TEXT = 
POSTGRESQL_TEXT = Builder.new( Parser::POSTGRESQL_TEXT )
TAB = 
Builder.new( Parser::TAB )
TABLE = 
Builder.new( Parser::TABLE )
FIXED = 
Builder.new( Parser::FIXED )
Parser =

add convenience shortcuts / aliases for CsvReader support classes

CsvReader::Parser
ParserFixed = 
CsvReader::ParserFixed
Converter = 
CsvReader::Converter

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(str_or_readable, headers: nil, sep: nil, converters: nil, header_converters: nil, parser: nil, **kwargs) ⇒ CsvHashReader

Returns a new instance of CsvHashReader.

Raises:

  • (ArgumentError) 


108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
 
# File 'lib/csvreader/reader_hash.rb', line 108

def initialize( str_or_readable, headers: nil, sep: nil,
                      converters: nil,
                      header_converters: nil,
                      parser: nil,
                      **kwargs )
      raise ArgumentError.new( "Cannot parse nil as CSV" )  if str_or_readable.nil?
      ## todo: use (why? why not) - raise ArgumentError, "Cannot parse nil as CSV"     if data.nil?

      # create the IO object we will read from
      @io = str_or_readable.is_a?(String) ? StringIO.new(str_or_readable) : str_or_readable

      ## pass in headers as array e.g. ['A', 'B', 'C']
      ##  double check: run header_converters on passed in headers?
      ##    for now - do NOT auto-convert passed in headers - keep them as-is (1:1)
      @names = headers ? headers : nil

      @sep    = sep
      @kwargs = kwargs

      @converters        = Converter.create_converters( converters )
      @header_converters = Converter.create_header_converters( header_converters )

      @parser = parser.nil? ? Parser::DEFAULT : parser
end

Class Method Details

.default ⇒ Object

alternative alias for DEFAULT



152
 
# File 'lib/csvreader/base.rb', line 152

def self.default()         DEFAULT;         end

.excel ⇒ Object

alternative alias for EXCEL



158
 
# File 'lib/csvreader/base.rb', line 158

def self.excel()           EXCEL;           end

.f ⇒ Object 



168
 
# File 'lib/csvreader/base.rb', line 168

def self.f()               fixed;           end

.fix ⇒ Object 



167
 
# File 'lib/csvreader/base.rb', line 167

def self.fix()             fixed;           end

.fixed ⇒ Object 



166
 
# File 'lib/csvreader/base.rb', line 166

def self.fixed()           FIXED;           end

.foreach(path, headers: nil, sep: nil, converters: nil, header_converters: nil, parser: nil, **kwargs, &block) ⇒ Object 



57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
 
# File 'lib/csvreader/reader_hash.rb', line 57

def self.foreach( path, headers: nil,
                        sep: nil,
                        converters: nil,
                        header_converters: nil,
                        parser: nil, **kwargs, &block )
  csv = open( path,
              headers: headers,
              sep: sep,
              converters: converters,
              header_converters: header_converters,
              parser: parser,
              **kwargs )

  if block_given?
    begin
      csv.each( &block )
    ensure
      csv.close
    end
  else
    csv.to_enum    ## note: caller (responsible) must close file!!!
    ## remove version without block given - why? why not?
    ## use Csv.open().to_enum  or Csv.open().each
    ##   or Csv.new( File.new() ).to_enum or Csv.new( File.new() ).each ???
  end
end

.mysql ⇒ Object 



159
 
# File 'lib/csvreader/base.rb', line 159

def self.mysql()           MYSQL;           end

.n ⇒ Object 



155
 
# File 'lib/csvreader/base.rb', line 155

def self.n()               numeric;         end

.num ⇒ Object 



154
 
# File 'lib/csvreader/base.rb', line 154

def self.num()             numeric;         end

.numeric ⇒ Object 



153
 
# File 'lib/csvreader/base.rb', line 153

def self.numeric()         NUMERIC;         end

.open(path, mode = nil, headers: nil, sep: nil, converters: nil, header_converters: nil, parser: nil, **kwargs, &block) ⇒ Object 



13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
 
# File 'lib/csvreader/reader_hash.rb', line 13

def self.open( path, mode=nil,
               headers: nil,
               sep: nil,
               converters: nil,
               header_converters: nil,
               parser: nil, **kwargs, &block )   ## rename path to filename or name - why? why not?

    ## note: default mode (if nil/not passed in) to 'r:bom|utf-8'
    f = File.open( path, mode ? mode : 'r:bom|utf-8' )
    csv = new(f, headers: headers,
                 sep: sep,
                 converters: converters,
                 header_converters: header_converters,
                 parser: parser, **kwargs )

    # handle blocks like Ruby's open(), not like the (old old) CSV library
    if block_given?
      begin
        block.call( csv )
      ensure
        csv.close
      end
    else
      csv
    end
end

.parse(str_or_readable, headers: nil, sep: nil, converters: nil, header_converters: nil, parser: nil, **kwargs, &block) ⇒ Object 



85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
 
# File 'lib/csvreader/reader_hash.rb', line 85

def self.parse( str_or_readable, headers: nil,
                      sep: nil,
                      converters: nil,
                      header_converters: nil,
                      parser: nil, **kwargs, &block )
  csv = new( str_or_readable,
             headers: headers,
             sep: sep,
             converters: converters,
             header_converters: header_converters,
             parser: parser, **kwargs )

  if block_given?
    csv.each( &block )  ## note: caller (responsible) must close file!!! - add autoclose - why? why not?
  else  # slurp contents, if no block is given
    csv.read            ## note: caller (responsible) must close file!!! - add autoclose - why? why not?
  end
end

.postgres ⇒ Object 



161
 
# File 'lib/csvreader/base.rb', line 161

def self.postgres()        postgresql;      end

.postgres_text ⇒ Object 



163
 
# File 'lib/csvreader/base.rb', line 163

def self.postgres_text()   postgresql_text; end

.postgresql ⇒ Object 



160
 
# File 'lib/csvreader/base.rb', line 160

def self.postgresql()      POSTGRESQL;      end

.postgresql_text ⇒ Object 



162
 
# File 'lib/csvreader/base.rb', line 162

def self.postgresql_text() POSTGRESQL_TEXT; end

.read(path, headers: nil, sep: nil, converters: nil, header_converters: nil, parser: nil, **kwargs) ⇒ Object 



41
42
43
44
45
46
47
48
49
50
51
52
53
 
# File 'lib/csvreader/reader_hash.rb', line 41

def self.read( path, headers: nil,
                     sep: nil,
                     converters: nil,
                     header_converters: nil,
                     parser: nil,
                     **kwargs )
    open( path,
          headers: headers,
          sep: sep,
          converters: converters,
          header_converters: header_converters,
          parser: parser, **kwargs ) { |csv| csv.read }
end

.rfc4180 ⇒ Object

alternative alias for RFC4180



157
 
# File 'lib/csvreader/base.rb', line 157

def self.rfc4180()         RFC4180;         end

.strict ⇒ Object

alternative alias for STRICT



156
 
# File 'lib/csvreader/base.rb', line 156

def self.strict()          STRICT;          end

.tab ⇒ Object 



164
 
# File 'lib/csvreader/base.rb', line 164

def self.tab()             TAB;             end

.table ⇒ Object 



165
 
# File 'lib/csvreader/base.rb', line 165

def self.table()           TABLE;           end

Instance Method Details

#each(&block) ⇒ Object 



152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
 
# File 'lib/csvreader/reader_hash.rb', line 152

def each( &block )

  ## todo/fix:
  ##   add case for headers/names.size != values.size
  ##   - add rest option? for if less headers than values (see python csv.DictReader - why? why not?)
  ##
  ##   handle case with duplicate and empty header names etc.


  if block_given?
    kwargs = {}
    ## note: only add separator if present/defined (not nil)
    ##  todo/fix: change sep keyword to "known" classes!!!!
    kwargs[:sep] = @sep    if @sep && @parser.respond_to?( :'sep=' )

    kwargs[:width] = @kwargs[:width]    if @parser.is_a?( ParserFixed )


    @parser.parse( @io, kwargs ) do |raw_values|     # sep: sep
       if @names.nil?    ## check for (first) headers row
         if @header_converters.empty?
           @names = raw_values   ## store header row / a.k.a. field/column names
         else
           values = []
           raw_values.each_with_index do |value,i|
             values << @header_converters.convert( value, i )
           end
           @names = values
         end
       else    ## "regular" record
         raw_record = @names.zip( raw_values ).to_h    ## todo/fix: check for more values than names/headers!!!
         if @converters.empty?
           block.call( raw_record )
         else
           ## add "post"-processing with converters pipeline
           ##   that is, convert all strings to integer, float, date, ... if wanted
           record = {}
           raw_record.each do | key, value |
             record[ key ] = @converters.convert( value, key )
           end
           block.call( record )
         end
       end
    end
  else
    to_enum
  end
end

#read ⇒ Object

method each



201
 
# File 'lib/csvreader/reader_hash.rb', line 201

def read() to_a; end