Class BinaryBlocker::Encoder
In: lib/blocker.rb
Parent: Object
GroupEncoder ListOfEncoder Blocker FixedArrayEncoder CountedArrayEncoder Encoder SimpleEncoder BitFieldEncoder OneOfEncoder PackedNumberEncoder PackedDateEncoder PackedDateTimeEncoder FixedStringEncoder FixedUTF16StringEncoder BinaryBlocker Module: BinaryBlocker

This is the base class for all the various encoders. It supports a variety of options (as Symbols in a Hash):

pre_block:passed the value before being blocked
post_block:passed the blocked value before returned
pre_deblock:passed the io before attempting to deblock it (hard to imagine why you would need this but I was compelled by orthaganality)
post_deblock:passed the deblocked value before being stored internally
get_filter:more info
set_filter:all done

It also supports either a string or io parameter which will be used to initialize the class

Methods

block   deblock   initialize_data   initialize_options   internal_block   internal_deblock   new   valid?   value   value=   with_guarded_io_pos  

Public Class methods

new(*opts)

Parameters: (io | buf, options_hash)

Options (lambda):

pre_block:passed the value before being blocked
post_block:passed the blocked value before returned
pre_deblock:passed the io before attempting to deblock it (hard to imagine why you would need this but I was compelled by orthaganality)
post_deblock:passed the deblocked value before being stored internally
get_filter:more info
set_filter:all done

[Source]

     # File lib/blocker.rb, line 108
108:     def initialize(*opts)
109:       initialize_options(*opts)
110:       initialize_data(*opts)
111:     end

Public Instance methods

block(io=nil)

[Source]

     # File lib/blocker.rb, line 114
114:     def block(io=nil)
115:       val = if @pre_block
116:         @pre_block.call(self.value)
117:       else
118:         self.value
119:       end
120:       result = internal_block(val)
121:       if @post_block
122:         result = @post_block.call(result)
123:       end
124:       io.write(result) if io
125:       result
126:     end
deblock(io)

This routine takes an io and will parse the stream on success it returns the object, on failure it returns a nil

[Source]

     # File lib/blocker.rb, line 131
131:     def deblock(io)
132:       with_guarded_io_pos(io) do
133:         if @pre_deblock
134:           # does this serve any real purpose? other
135:           # than making me feel good and orthoginal
136:           io = @pre_deblock.call(io)
137:         end
138:         self.value = internal_deblock(io)
139:         if @post_deblock
140:           self.value = @post_deblock.call(self.value)
141:         end
142:         self.value
143:       end
144:     end

Protected Instance methods

initialize_data(*opts)

[Source]

     # File lib/blocker.rb, line 184
184:     def initialize_data(*opts)
185:       data = opts.find { |o| !o.respond_to? :to_hash }
186:       if data.respond_to? :to_str
187:         raise "Unable to parse block" unless deblock(StringIO.new(data))
188:       elsif data.respond_to? :read
189:         raise "Unable to parse block" unless deblock(data)        
190:       end
191:     end
initialize_options(*opts)

[Source]

     # File lib/blocker.rb, line 168
168:     def initialize_options(*opts)
169:       @opts ||= {}
170:       opts = opts.find { |o| o.respond_to? :to_hash }
171:       if opts
172:         @opts = @opts.merge(opts)
173:         @pre_block = @opts[:pre_block]
174:         @pre_deblock = @opts[:pre_deblock]
175:         
176:         @get_filter = @opts[:get_filter]
177:         @set_filter = @opts[:set_filter]
178:         
179:         @post_block = @opts[:post_block]
180:         @post_deblock = @opts[:post_deblock]
181:       end
182:     end
internal_block(value)

[Source]

     # File lib/blocker.rb, line 201
201:     def internal_block(value) 
202:       value
203:     end
internal_deblock(io)

[Source]

     # File lib/blocker.rb, line 205
205:     def internal_deblock(io)
206:       ''
207:     end
valid?()

Override valid? to allow check constraints on a particular record type, on failure

[Source]

     # File lib/blocker.rb, line 150
150:     def valid?
151:       true
152:     end
value()

[Source]

     # File lib/blocker.rb, line 154
154:     def value
155:       v = @value
156:       if @get_filter
157:         @get_filter.call(v) 
158:       else
159:         v
160:       end
161:     end
value=(val)

[Source]

     # File lib/blocker.rb, line 163
163:     def value=(val)
164:       val = @set_filter.call(val) if @set_filter
165:       @value = val
166:     end
with_guarded_io_pos(io) {|io| ...}

[Source]

     # File lib/blocker.rb, line 193
193:     def with_guarded_io_pos(io)
194:       result = nil
195:       BinaryBlocker.with_guarded_io_pos(io) do
196:         result = yield io
197:         valid?
198:       end && result
199:     end

[Validate]