checkin files after meeting...

Author: Allen Maxwell

README.md

@@ -39,6 +39,9 @@ Basic things to discuss and watch out for:
 *	uploading csv files to server in rails apps - timeout issues.   I've had to deal with this using the delayed_jobs gem because rails will time out if the csv file is too large.  
 
 # Coding Exercise - let's build a csv parser! (oh boy!!!)
+
+###### the code can be published for other users by adding it to this gist: https://gist.github.com/aamax/3fdf85c50407bad9c630
+
 The challenge this month is to build a parser to read csv files.  The parameters are as follows:
 *	You may NOT use any external libraries for reading csv files (like faster csv) to solve the challenge.
 *	You must account for quoted strings (quotes will always be double quote chars: "") and allow the file delimiter to be embedded within the quotes

import_files/final_transactions.csv

@@ -0,0 +1,9 @@
+product_id,name
+1,MacBook Pro
+2,Dell PC Laptop
+3,HP Desktop PC
+4,BlueTooth Keyboard and Mouse
+5,"21"" flat screen LCD Monitor"
+6,"""All in One Printer, Scanner, Fax"""
+7,"""Office Furniture: chair, desk, lamp"""
+8,business card holder

import_files/prodfile.csv

@@ -0,0 +1,14 @@
+product_id,date,quantity,price
+1,1/1/13,3,2400
+1,1/15/13,1,900
+2,2/12/13,1,1000
+3,4/1/13,1,1250
+4,5/2/14,15,65
+2,6/16/14,3,750
+8,6/30/14,5,12.5
+6,9/3/14,3,225
+6,9/4/14,2,235
+7,9/15/14,25,1200
+5,9/16/14,25,175
+5,9/20/14,3,195
+7,9/21/14,3,1300

import_files/product_file1.csv

@@ -0,0 +1,53 @@
+product_id,date,price,quantity
+1,1/1/13,2400,"""3"""
+1,1/15/13,900,1
+2,2/12/13,1000,1
+3,4/1/13,1250,1
+4,5/2/14,65,15
+2,6/16/14,750,3
+8,6/30/14,12.5,5
+6,9/3/14,225,3
+6,9/4/14,235,2
+7,9/15/14,1200,25
+5,9/16/14,175,25
+5,9/20/14,195,3
+7,9/21/14,1300,3
+1,1/1/13,2400,3
+1,1/15/13,900,1
+2,2/12/13,1000,1
+3,4/1/13,1250,1
+4,5/2/14,65,"""15"""
+2,6/16/14,750,3
+8,6/30/14,12.5,5
+6,9/3/14,225,3
+6,9/4/14,235,2
+7,9/15/14,1200,25
+5,9/16/14,175,25
+5,9/20/14,195,3
+7,9/21/14,"""1300""",3
+1,1/1/13,2400,3
+1,1/15/13,900,1
+2,2/12/13,1000,1
+3,4/1/13,1250,1
+4,5/2/14,65,15
+2,6/16/14,750,3
+8,6/30/14,12.5,5
+6,9/3/14,225,3
+6,9/4/14,235,2
+7,9/15/14,1200,25
+5,9/16/14,175,25
+5,9/20/14,195,3
+7,9/21/14,1300,3
+1,1/1/13,2400,3
+1,1/15/13,"""900""",1
+2,2/12/13,1000,1
+3,4/1/13,1250,1
+4,5/2/14,65,15
+2,6/16/14,750,3
+"""8""",6/30/14,12.5,5
+6,9/3/14,225,3
+6,9/4/14,235,2
+7,9/15/14,1200,25
+5,9/16/14,175,25
+5,9/20/14,195,3
+"""7""",9/21/14,1300,3

import_files/trans.csv

@@ -0,0 +1,85 @@
+class Parser
+  def initialize filename, delimiter=","
+    @fhandle = File.open(filename, 'r')
+    @delim = delimiter
+    @header = []
+    @arr_val = []
+    line_str = @fhandle.readline
+    @header = parse_row(line_str)
+  end
+  
+  def header
+    @header
+  end
+  
+  def eof?
+    @fhandle.eof?
+  end
+  
+  def read
+    line_str = @fhandle.readline
+    parse_row(line_str)
+  end
+  
+  def parse_row(line)
+    ret_val = []
+    while !line.nil? && line.length > 0
+      result = parse_field(line)
+      line = result[1]
+      ret_val << result[0]
+    end
+    ret_val
+  end
+  
+  def parse_field(str)
+    str.chomp!
+    ret_val = []
+    if str[0] != '"'
+      field = str.split(@delim)[0]
+      ret_val << field
+      ret_val << str[field.length + 1, str.length]
+    else
+      idx = 1
+      
+puts " idx: #{idx} quoted field: #{str}"      if str[0] == '"'
+
+
+      while true
+        if str[idx] == '"'
+          # read to quote followed by delim or eol
+          if (idx == str.length - 1) || (str[idx + 1] == @delim)
+            fld = str[1..idx]
+            str = str[idx + 2, str.length]
+            ret_val = [fld, str]
+            break
+          end
+          idx += 1
+        else
+          # read to next delim or eol
+          if (idx == str.length - 1) || (str[idx] == @delim)
+            fld = str[0..idx - 1]
+            str = str[idx + 1, str.length]
+            ret_val = [fld, str]
+            break
+          end
+          idx += 1
+        end       
+        break if str.empty?
+      end      
+    
+    end
+    ret_val
+  end
+  
+  def close
+    @fhandle.close if @fhandle
+  end
+  
+end
+
+p = Parser.new('./import_files/prodfile.csv')
+puts "Header: #{p.header}"
+until p.eof?
+  puts p.read.map {|v| v}.join(',')
+end
+p.close