Class: CodeZauker::FileScanner

Inherits:
Object
  • Object
show all
Defined in:
lib/code_zauker.rb

Overview

Scan a file and push it inside redis... then it can provide handy method to find file scontaining the trigram...

Instance Method Summary (collapse)

Constructor Details

- (FileScanner) initialize(redisConnection = nil)

A new instance of FileScanner



112
113
114
115
116
117
118
# File 'lib/code_zauker.rb', line 112

def initialize(redisConnection=nil)
  if redisConnection==nil
    @redis=Redis.new
  else
    @redis=redisConnection
  end
end

Instance Method Details

- (Object) disconnect



121
122
123
# File 'lib/code_zauker.rb', line 121

def disconnect()    
  @redis.quit
end

- (Object) isearch(term)

Do a case-insenitive search

using the special set of trigrams "trigram:ci:*" all downcase



282
283
284
285
286
287
288
289
290
# File 'lib/code_zauker.rb', line 282

def isearch(term)
  termLowercase=term.downcase()
  trigramInAnd=split_in_trigrams(termLowercase,"trigram:ci")
  if trigramInAnd.length==0
    return []
  end      
  fileIds=    @redis.sinter(*trigramInAnd)
  return map_ids_to_files(fileIds)      
end

- (Object) load(filename, noReload = false)



184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
# File 'lib/code_zauker.rb', line 184

def load(filename, noReload=false)
  # Define my redis id...      
  # Already exists?...
  fid=@redis.get "fscan:id:#{filename}"
  if fid==nil 
    @redis.setnx "fscan:nextId",0
    fid=@redis.incr "fscan:nextId"
    # BUG: Consider storing it at the END of the processing
    @redis.set "fscan:id:#{filename}", fid
    @redis.set "fscan:id2filename:#{fid}",filename
  else
    if noReload 
      #puts "Already found #{filename} as id:#{fid} and NOT RELOADED"
      return nil
    end
  end      
  # fid is the set key!...
  trigramScanned=0
  # TEST_LICENSE.txt: 3290 Total Scanned: 24628
  # The ratio is below 13% of total trigrams are unique for very big files
  # So we avoid a huge roundtrip to redis, and store the trigram on a memory-based set
  # before sending it to redis. This avoid
  # a lot of spourios work      
  s=Set.new
  util=Util.new()
  lines=util.get_lines(filename)
  adaptiveSize= TRIGRAM_DEFAULT_PUSH_SIZE

  lines.each do  |lineNotUTF8|
    l= util.ensureUTF8(lineNotUTF8)
    # Split each line into 3-char chunks, and store in a redis set
    i=0
    for istart in 0...(l.length-GRAM_SIZE) 
      trigram = l[istart, GRAM_SIZE]
      # Avoid storing the 3space guy enterely
      if trigram==SPACE_GUY
        next
      end
      # push the trigram to redis (highly optimized)
      s.add(trigram)
      if s.length > adaptiveSize
        pushTrigramsSet(s,fid,filename)
        s=Set.new()             
      end
      trigramScanned += 1
      #puts "#{istart} Trigram fscan:#{trigram}/  FileId: #{fid}"
    end
  end
  

  if s.length > 0
    pushTrigramsSet(s,fid,filename)
    s=nil
    #puts "Final push of #{s.length}"
  end


  trigramsOnFile=@redis.scard "fscan:trigramsOnFile:#{fid}"
  @redis.sadd "fscan:processedFiles", "#{filename}"
  trigramRatio=( (trigramsOnFile*1.0) / trigramScanned )* 100.0
  if trigramRatio < 10 or trigramRatio >75        
    puts "#{filename}\n\tRatio:#{trigramRatio.round}%  Unique Trigrams:#{trigramsOnFile} Total Scanned: #{trigramScanned} ?Binary" if trigramRatio >90 and trigramsOnFile>70
  end
  return nil
end

- (Object) map_ids_to_files(fileIds)



264
265
266
267
268
269
270
271
272
273
# File 'lib/code_zauker.rb', line 264

def map_ids_to_files(fileIds)
  filenames=[]
  # fscan:id2filename:#{fid}....
  fileIds.each do | id |
    file_name=@redis.get("fscan:id2filename:#{id}")
    filenames.push(file_name)  if !file_name.nil?
  end      
  #puts " ** Files found:#{filenames} from ids #{fileIds}"
  return filenames
end

- (Object) reindex(fileList)



312
313
314
315
316
317
318
# File 'lib/code_zauker.rb', line 312

def reindex(fileList)
  #puts "Reindexing... #{fileList.length} files..."
  fileList.each do |current_file |
    self.remove([current_file])        
    self.load(current_file,noReload=false)
  end
end

- (Object) remove(filePaths = nil)

Remove the files from the index, updating trigrams



333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
# File 'lib/code_zauker.rb', line 333

def remove(filePaths=nil)
  if filePaths==nil
    fileList=[]
    storedFiles=@redis.keys "fscan:id:*"
    storedFiles.each do |fileKey|
      filename=fileKey.split("fscan:id:")[1]
      fileList.push(filename)
    end
  else
    fileList=filePaths
  end
  # puts "Files to remove from index...#{fileList.length}"      
  fileList.each do |filename|
    fid=@redis.get "fscan:id:#{filename}"
    trigramsToExpurge=@redis.smembers "fscan:trigramsOnFile:#{fid}"
    if trigramsToExpurge.length==0
      puts "?Nothing to do on #{filename}"
    end
    puts "#{filename} id=#{fid} Trigrams: #{trigramsToExpurge.length} Expurging..."        
    trigramsToExpurge.each do | ts |
      @redis.srem "trigram:#{ts}", fid
      begin
        @redis.srem "trigram:ci:#{ts.downcase}",fid
        #putc "."
      rescue ArgumentError
        # Ignore  "ArgumentError: invalid byte sequence in UTF-8"
        # and proceed...
      end
    end
    #putc "\n"
    
    @redis.del  "fscan:id:#{filename}", "fscan:trigramsOnFile:#{fid}", "fscan:id2filename:#{fid}"
    @redis.srem "fscan:processedFiles",  filename
  end
  return nil
end

- (Object) removeAll

Remove all the keys



321
322
323
324
325
326
327
328
329
330
# File 'lib/code_zauker.rb', line 321

def removeAll()
  tokill=[]
  tokill=@redis.keys("fscan:*")
  tokill.push(*(@redis.keys("trigram*")))      
  tokill.each do | x |
    @redis.del x
    #puts "Deleted #x"
  end
  @redis.del "fscan:processedFiles"
end

- (Object) search(term)

search

Find a list of file candidates to a search string The search string is padded into trigrams



296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
# File 'lib/code_zauker.rb', line 296

def search(term)
  if term.length < GRAM_SIZE
    raise "FATAL: #{term} is shorter then the minimum size of #{GRAM_SIZE} character"
  end
  #puts " ** Searching: #{term}"
  trigramInAnd=split_in_trigrams(term,"trigram")
  #puts "Trigam conversion /#{term}/ into #{trigramInAnd}"
  if trigramInAnd.length==0
    return []
  end      
  fileIds=    @redis.sinter(*trigramInAnd)
  fileNames=map_ids_to_files(fileIds)
  #puts "DEBUG #{fileIds} #{fileNames}"
  return fileNames
end