Class: Flydata::MysqlCompatibilityCheck

Inherits:
CompatibilityCheck show all
Defined in:
lib/flydata/compatibility_check.rb

Defined Under Namespace

Classes: MysqlCompatibilityError

Constant Summary collapse

SELECT_QUERY_TMPLT = 
"SELECT %s"
BINLOG_RETENTION_HOURS = 
24

Instance Method Summary collapse

Methods inherited from CompatibilityCheck

#check

Methods included from CommandLoggable

#before_logging, #log_error_stderr, #log_info_stdout, #log_warn_stderr

Constructor Details

#initialize(dp_hash, de_hash, options = {}) ⇒ MysqlCompatibilityCheck

def initialize(de_hash, dump_dir=nil)



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# File 'lib/flydata/compatibility_check.rb', line 81

def initialize(dp_hash, de_hash, options={})
  super
  @db_opts = [:host, :port, :username, :password, :database].inject({}) {|h, sym| h[sym] = de_hash[sym.to_s]; h}
  @dump_dir = options['dump_dir'] || nil
end

Instance Method Details

#check_mysql_binlog_retention ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 173

def check_mysql_binlog_retention
  client = Mysql2::Client.new(@db_opts)
  begin
    if is_rds?(@db_opts[:host])
      run_rds_retention_check(client)
    else
      run_mysql_retention_check(client)
    end
  ensure
    client.close
  end
end

#check_mysql_protocol_tcp_compat ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 119

def check_mysql_protocol_tcp_compat
  query = "MYSQL_PWD=\"#{@db_opts[:password]}\" mysql -u #{@db_opts[:username]} -h #{@db_opts[:host]} -P #{@db_opts[:port]} #{@db_opts[:database]} -e \"SHOW GRANTS;\" --protocol=tcp"

  Open3.popen3(query) do |stdin, stdout, stderr|
    stdin.close
    while !stderr.eof?
      lines = []
      while line = stderr.gets; lines << line.strip; end
      err_reason = lines.join(" ")
      log_error("Error occured during access to mysql server.", {err: err_reason})

      unless /Warning: Using a password on the command line interface can be insecure/ === err_reason
        raise MysqlCompatibilityError, "Cannot connect to MySQL database. Please make sure you can connect with this command:\n      $ mysql -u #{@db_opts[:username]} -h #{@db_opts[:host]} -P #{@db_opts[:port]} #{@db_opts[:database]} --protocol=tcp -p"
      end
    end
  end
end

#check_mysql_row_mode_compat ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 137

def check_mysql_row_mode_compat
  sys_var_to_check = {'@@binlog_format'=>'ROW', '@@binlog_checksum'=>'NONE', '@@log_bin_use_v1_row_events'=>1}
  errors={}

  client = Mysql2::Client.new(@db_opts)

  begin
    sys_var_to_check.each_key do |sys_var|
      sel_query = SELECT_QUERY_TMPLT % sys_var
      begin
        result = client.query(sel_query)
        unless result.first[sys_var] == sys_var_to_check[sys_var]
          errors[sys_var]=result.first[sys_var]
        end
      rescue Mysql2::Error => e
        if e.message =~ /Unknown system variable/
          unless e.message =~ /(binlog_checksum|log_bin_use_v1_row_events)/
            errors[sys_var] = false
          end
        else
          raise e
        end
      end
    end
  ensure
    client.close
  end
  unless errors.empty?
    error_explanation = ""
    errors.each_key do |err_key|
      error_explanation << "\n    * #{err_key} is #{errors[err_key]} but should be #{sys_var_to_check[err_key]}"
    end
    raise MysqlCompatibilityError, "These system variable(s) are not the correct value: #{error_explanation}\n   Please change these system variables for FlyData Sync to run correctly"
  end
end

#check_mysql_user_compat ⇒ Object

Raises:



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# File 'lib/flydata/compatibility_check.rb', line 96

def check_mysql_user_compat
  client = Mysql2::Client.new(@db_opts)
  grants_sql = "SHOW GRANTS"
  correct_db = ["ON (\\*|#{@db_opts[:database]})","TO '#{@db_opts[:username]}"]
  necessary_permission_fields= ["SELECT","RELOAD","LOCK TABLES","REPLICATION SLAVE","REPLICATION CLIENT"]
  all_privileges_field= ["ALL PRIVILEGES"]
  result = client.query(grants_sql)
  # Do not catch MySQL connection problem because check should stop if no MySQL connection can be made.
  client.close
  missing_priv = []
  result.each do |res|
    # SHOW GRANTS should only return one column
    res_value = res.values.first
    if correct_db.all? {|perm| res_value.match(perm)}
      necessary_permission_fields.each do |priv|
        missing_priv << priv unless res_value.match(priv)
      end
      return true if missing_priv.empty? or all_privileges_field.all? {|d| res_value.match(d)}
    end
  end
  raise MysqlCompatibilityError, "The user '#{@db_opts[:username]}' does not have the correct permissions to run FlyData Sync\n    * These privileges are missing: #{missing_priv.join(", ")}"
end

#check_writing_permissions ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 186

def check_writing_permissions
  write_errors = []
  paths_to_check = ["~/.flydata"]
  paths_to_check << @dump_dir unless @dump_dir.to_s.empty?
  paths_to_check.each do |path|
    full_path = File.expand_path(path)
    full_path = File.dirname(full_path) unless File.directory?(full_path)
    write_errors << full_path unless File.writable?(full_path)
  end
  unless write_errors.empty?
    error_dir = write_errors.join(", ")
    raise MysqlCompatibilityError, "We cannot access the directories: #{error_dir}"
  end
end

#is_rds?(hostname) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/flydata/compatibility_check.rb', line 239

def is_rds?(hostname)
  hostname.match(/rds.amazonaws.com$/) != nil
end

#print_errors ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 87

def print_errors
  return if @errors.empty?
  log_error_stderr "There may be some compatibility issues with your MySQL credentials: "
  @errors.each do |error|
    log_error_stderr "  * #{error.message}"
  end
  raise "Please correct these errors if you wish to run FlyData Sync"
end

#run_mysql_retention_check(mysql_client) ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 201

def run_mysql_retention_check(mysql_client)
  expire_logs_days_limit = BINLOG_RETENTION_HOURS / 24
  sel_query = SELECT_QUERY_TMPLT % '@@expire_logs_days'
  result = mysql_client.query(sel_query)
  if result.first["@@expire_logs_days"]!=0 and result.first["@@expire_logs_days"] <= expire_logs_days_limit
    raise MysqlCompatibilityError, "Binary log retention is too short\n " +
      "  We recommend the system variable '@@expire_logs_days' to be either set to 0 or at least #{expire_logs_days_limit} days"
  end
end

#run_rds_retention_check(mysql_client) ⇒ Object 



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# File 'lib/flydata/compatibility_check.rb', line 211

def run_rds_retention_check(mysql_client)
  sql_query =  "call mysql.rds_show_configuration;"

  begin
    result = mysql_client.query(sql_query)
    if result.first["name"]=="binlog retention hours"
      if result.first["value"].nil? or result.first["value"].to_i <= BINLOG_RETENTION_HOURS
        raise MysqlCompatibilityError, "Binary log retention is too short\n" +
                                       "  We recommend setting RDS binlog retention to be at least #{BINLOG_RETENTION_HOURS} hours. To do this, run this on your RDS MySQL database:\n" +
                                       "  $> call mysql.rds_set_configuration('binlog retention hours', 94);"
      end
    end
  rescue Mysql2::Error => e
    if e.message =~ /command denied to user/
      log_warn_stderr("[WARNING]Cannot verify RDS retention period on currend MySQL user account.\n" +
                      "To see retention period, please run this on your RDS:\n" +
                      "  $> call mysql.rds_show_configuration;\n" +
                      "Please verify that the hours is not nil and is at least #{BINLOG_RETENTION_HOURS} hours\n" +
                      "To set binlog retention hours, you can run this on your RDS:\n" +
                      "  $> call mysql.rds_set_configuration('binlog retention hours', #{BINLOG_RETENTION_HOURS});\n"
                     )
    else
      raise e
    end
  end

end