Module: Mohair

Defined in:
lib/mohair.rb,
lib/mohair/version.rb,
lib/mohair/inserter.rb,
lib/mohair/selector.rb,
lib/mohair/sql/tree.rb,
lib/mohair/sql/parser.rb,
lib/mohair/sql/select.rb

Defined Under Namespace

Modules: Sql Classes: Column, Condition, Delete, From, Function, Group, Insert, Inserter, Order, Select, Update, Where

Constant Summary collapse

VERSION = 
"0.0.3"
MapperTemplate = 
"function(v){\n  var f = function(key, obj){\n    var ret = {};\n    <% select.each do |c| %>\n    <%=  c %>\n    <% end %>\n    ret.__key = key;\n    <%= where %>\n  };\n  var raw_obj = JSON.parse(v.values[0].data);\n  if(raw_obj instanceof Array){\n    var ret0 = [];\n    for(var i in raw_obj){\n      ret0 = ret0.concat(f(v.key, raw_obj[i]));\n    }\n    return ret0;\n  }else{\n    return f(v.key, raw_obj);\n  }\n}\n"
ReducerTemplate = 
"function(values){\n  var ret = {};\n  // init lines\n  <%= agg_init %>\n  for(var i in values){\n    var v=values[i];\n    <%= agg_fun %>\n  }\n  return [ret];\n}\n"
GetAllMapper =

if(!!(v.sum_age)){ ret.sum_age += v.sum_age; }

"function(v){\n  var f = function(key, obj){\n    var ret = obj;\n    ret.__key = key;\n    <%= where %>\n  };\n  var raw_obj = JSON.parse(v.values[0].data);\n  if(raw_obj instanceof Array){\n    var ret0 = [];\n    for(var i in raw_obj){\n      ret0 = ret0.concat(f(v.key, raw_obj[i]));\n    }\n    return ret0;\n  }else{\n    return f(v.key, raw_obj);\n  }\n}\n"
GroupByMapperTemplate = 
"function(v){\n  ejsLog('/tmp/map_reduce.log', \"startmapper>\")\n  var f = function(key, obj){\n    var ret = {};\n    <% select.each do |c| %>\n    <%=  c %>\n    <% end %>\n    ret.__key = key;\n    <%= where %>\n  };\n  var arr = [];\n  var raw_obj = JSON.parse(v.values[0].data);\n  if(raw_obj instanceof Array){\n    var ret0 = [];\n    for(var i in raw_obj){\n      ret0 = ret0.concat(f(v.key, raw_obj[i]));\n    }\n    arr = ret0;\n  }else{\n    arr = f(v.key, raw_obj);\n  }\n  var ret = {};\n  for(var i in arr){\n    //ejsLog('/tmp/map_reduce.log', JSON.stringify(arr[i].<%= col %>))\n    var col = arr[i].<%= col %>;\n    //ejsLog('/tmp/map_reduce.log', JSON.stringify(col))\n    if(ret[col]){\n      ret[col] = ret[col].push(arr[i]);\n      //ejsLog('/tmp/map_reduce.log', JSON.stringify(ret[col]))\n    }else{\n      ret[col] = [arr[i]];\n      //ejsLog('/tmp/map_reduce.log', JSON.stringify(ret[col]))\n    }\n  }\n  ejsLog('/tmp/map_reduce.log', \"<eomapper\")\n  return [ret];\n}\n"
GroupByReducerTemplate =

merge them all

{ k, v }, .…

-> v

"function(values){\n  ejsLog('/tmp/map_reduce.log', \"start>\");\n  var ret = {};\n  for(var i in values){\n  ejsLog('/tmp/map_reduce.log', JSON.stringify(i))\n    for(var a in values[i]){\n      if(ret[a]){\n        ret[a] = ret[a].concat(values[i][a]);\n      }else{\n        ret[a] = values[i][a];\n      }\n    }\n  }\n  ejsLog('/tmp/map_reduce.log', \"<end\");\n//  ejsLog('/tmp/map_reduce.log', JSON.stringify(ret))\n  return [ret];\n}\n"

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.build(tree) ⇒ Object 



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# File 'lib/mohair/sql/tree.rb', line 6

def Mohair.build tree
  case tree[:op]
  when 'select'
    Select.new tree
  when 'insert'
    Insert.new tree
  when 'update'
    Update.new tree
  when 'delete'
    Delete.new tree
  else
    LOG.error "bad :op", tree
  end
end

.do_dump ⇒ Object 



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# File 'lib/mohair.rb', line 83

def self.do_dump
  objs = JSON.load(STDIN)
  Inserter.new(ARGV[0]).insert_all(objs)
end

.format_result(results) ⇒ Object 



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# File 'lib/mohair/selector.rb', line 128

def Mohair.format_result results
  columns = Set.new
  results.each do |r|
    r.each do |k,v|
      columns.add(k)
    end
  end
  columns.delete('__key')
  cols = columns.to_a.join("\t| ")
  print "|               | #{cols}|\n"
  print "+---------------+------------------------------+\n"
  results.each do |r|
    print "| #{r['__key']}\t| "
    columns.to_a.each do |c|
      print "#{r[c]} \t| "
    end
    print "\n"
  end
end

.main ⇒ Object 



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# File 'lib/mohair.rb', line 29

def self.main

  q = nil #query!!
  index = nil

  opt = OptionParser.new
  opt.on('-q Q'){|v| q = v}
  opt.on('-i INDEX'){|v| index = v}
  opt.on('-h', '--help'){ usage }

  opt.parse!(ARGV)

  parser = Sql::Parser.new
  sql_syntax_tree =  parser.parse (q.strip)
  LOG.debug sql_syntax_tree

  case sql_syntax_tree[:op]
  when 'select'

    s = (Mohair.build sql_syntax_tree)

    LOG.debug "mapper->\n"
    LOG.debug s.mapper
    LOG.debug "reducer->\n"
    LOG.debug s.reducer
    
    client = Riak::Client.new(:protocol => "http")
    bucket = Riak::MapReduce.new(client)
      .add(client.bucket(s.bucket))## keyfilsters and so on here
    
    reducer = s.reducer
    result = nil
    if reducer.nil? then
      result = bucket.map(s.mapper, :keep => true)
        .run
    else
      result = bucket.map(s.mapper, :keep => false)
        .reduce(reducer, :keep => true)
        .run
    end

    #LOG.debug "raw query result> #{result}"
    LOG.info "query result:"
    format_result result

  # when :insert
  # when :show
  when :create
    LOG.error "CREATE sentence is unavailable at mohair"
  else
    LOG.error "bad query: ", result, "\n"
  end
end

.usage ⇒ Object 



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# File 'lib/mohair.rb', line 17

def self.usage
  print "usage:\n $ mohair -q \"select foo, bar from bucket_name\" [-i INDEX]\n $ mohair_dump <bucket_name> < sample_data.json\n\ninsert, delete sentence is future work\nmohair version \#{Mohair::VERSION}\n"
  exit -1
end

Instance Method Details

#any(arr, fun) ⇒ Object 



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# File 'lib/mohair/sql/select.rb', line 84

def any(arr, fun)
  arr.each do |e|
    if fun(e) then
      return true
    end
  end
  return false
end