class MCollective::RPC::Helpers

Various utilities for the RPC system

Public Class Methods

add_simplerpc_options(parser, options) click to toggle source

Add SimpleRPC common options

# File lib/mcollective/rpc/helpers.rb, line 251
def self.add_simplerpc_options(parser, options)
    parser.separator ""

    # add SimpleRPC specific options to all clients that use our library
    parser.on('--np', '--no-progress', 'Do not show the progress bar') do |v|
        options[:progress_bar] = false
    end

    parser.on('--one', '-1', 'Send request to only one discovered nodes') do |v|
        options[:mcollective_limit_targets] = "1"
    end

    parser.on('--limit-nodes [COUNT]', '--ln [COUNT]', 'Send request to only a subset of nodes, can be a percentage') do |v|
        options[:mcollective_limit_targets] = v
    end
end
color(code) click to toggle source

Return color codes, if the config color= option is false just return a empty string

# File lib/mcollective/rpc/helpers.rb, line 38
def self.color(code)
    colorize = Config.instance.color

    colors = {:red => "",
              :green => "",
              :yellow => "",
              :cyan => "",
              :bold => "",
              :reset => ""}

    if colorize
        return colors[code] || ""
    else
        return ""
    end
end
colorize(code, msg) click to toggle source

Helper to return a string in specific color

# File lib/mcollective/rpc/helpers.rb, line 56
def self.colorize(code, msg)
    "#{self.color(code)}#{msg}#{self.color(:reset)}"
end
command_in_path?(command) click to toggle source

Checks in PATH returns true if the command is found

# File lib/mcollective/rpc/helpers.rb, line 6
def self.command_in_path?(command)
    found = ENV["PATH"].split(File::PATH_SEPARATOR).map do |p|
        File.exist?(File.join(p, command))
    end

    found.include?(true)
end
old_rpcresults(result, flags = {}) click to toggle source

Backward compatible display block for results without a DDL

# File lib/mcollective/rpc/helpers.rb, line 199
def self.old_rpcresults(result, flags = {})
    result_text = ""

    if flags[:flatten]
        result.each do |r|
            if r[:statuscode] <= 1
                data = r[:data]

                unless data.is_a?(String)
                    result_text << data.pretty_inspect
                else
                    result_text << data
                end
            else
                result_text << r.pretty_inspect
            end
        end

        result_text << ""
    else
        [result].flatten.each do |r|

            if flags[:verbose]
                result_text << "%-40s: %s\n" % [r[:sender], r[:statusmsg]]

                if r[:statuscode] <= 1
                    r[:data].pretty_inspect.split("\n").each {|m| result_text += "    #{m}"}
                    result_text << "\n\n"
                elsif r[:statuscode] == 2
                    # dont print anything, no useful data to display
                    # past what was already shown
                elsif r[:statuscode] == 3
                    # dont print anything, no useful data to display
                    # past what was already shown
                elsif r[:statuscode] == 4
                    # dont print anything, no useful data to display
                    # past what was already shown
                else
                    result_text << "    #{r[:statusmsg]}"
                end
            else
                unless r[:statuscode] == 0
                    result_text << "%-40s %s\n" % [r[:sender], colorize(:red, r[:statusmsg])]
                end
            end
        end
    end

    result_text << ""
end
rpcresults(result, flags = {}) click to toggle source

Returns a blob of text representing the results in a standard way

It tries hard to do sane things so you often should not need to write your own display functions

If the agent you are getting results for has a DDL it will use the hints in there to do the right thing specifically it will look at the values of display in the DDL to choose when to show results

If you do not have a DDL you can pass these flags:

printrpc exim.mailq, :flatten => true
printrpc exim.mailq, :verbose => true

If you’ve asked it to flatten the result it will not print sender hostnames, it will just print the result as if it’s one huge result, handy for things like showing a combined mailq.

# File lib/mcollective/rpc/helpers.rb, line 78
def self.rpcresults(result, flags = {})
    flags = {:verbose => false, :flatten => false}.merge(flags)

    result_text = ""
    ddl = nil

    # if running in verbose mode, just use the old style print
    # no need for all the DDL helpers obfuscating the result
    if flags[:verbose]
        result_text = old_rpcresults(result, flags)
    else
        [result].flatten.each do |r|
            begin
                ddl ||= DDL.new(r.agent).action_interface(r.action.to_s)

                sender = r[:sender]
                status = r[:statuscode]
                message = r[:statusmsg]
                display = ddl[:display]
                result = r[:data]

                # appand the results only according to what the DDL says
                case display
                    when :ok
                        if status == 0
                            result_text << text_for_result(sender, status, message, result, ddl)
                        end

                    when :failed
                        if status > 0
                            result_text << text_for_result(sender, status, message, result, ddl)
                        end

                    when :always
                        result_text << text_for_result(sender, status, message, result, ddl)

                    when :flatten
                        result_text << text_for_flattened_result(status, result)

                end
            rescue Exception => e
                # no DDL so just do the old style print unchanged for
                # backward compat
                result_text = old_rpcresults(result, flags)
            end
        end
    end

    result_text
end
terminal_dimensions() click to toggle source

Figures out the columns and liens of the current tty

Returns [0, 0] if it can’t figure it out or if you’re not running on a tty

# File lib/mcollective/rpc/helpers.rb, line 18
def self.terminal_dimensions
    return [0, 0] unless STDIN.tty?

    if ENV["COLUMNS"] && ENV["LINES"]
        return [ENV["COLUMNS"].to_i, ENV["LINES"].to_i]

    elsif ENV["TERM"] && command_in_path?("tput")
        return [%xtput cols`.to_i, %xtput lines`.to_i]

    elsif command_in_path?('stty')
        return %xstty size`.scan(%r\d+/).map {|s| s.to_i }
    else
        return [0, 0]
    end
rescue
    [0, 0]
end
text_for_flattened_result(status, result) click to toggle source

Returns text representing a flattened result of only good data

# File lib/mcollective/rpc/helpers.rb, line 186
def self.text_for_flattened_result(status, result)
    result_text = ""

    if status <= 1
        unless result.is_a?(String)
            result_text << result.pretty_inspect
        else
            result_text << result
        end
    end
end
text_for_result(sender, status, msg, result, ddl) click to toggle source

Return text representing a result

# File lib/mcollective/rpc/helpers.rb, line 130
def self.text_for_result(sender, status, msg, result, ddl)
    statusses = ["",
                 colorize(:red, "Request Aborted"),
                 colorize(:yellow, "Unknown Action"),
                 colorize(:yellow, "Missing Request Data"),
                 colorize(:yellow, "Invalid Request Data"),
                 colorize(:red, "Unknown Request Status")]

    result_text = "%-40s %s\n" % [sender, statusses[status]]
    result_text << "   %s\n" % [colorize(:yellow, msg)] unless msg == "OK"

    # only print good data, ignore data that results from failure
    if [0, 1].include?(status)
        if result.is_a?(Hash)
            # figure out the lengths of the display as strings, we'll use
            # it later to correctly justify the output
            lengths = result.keys.map do |k|
                begin
                    ddl[:output][k][:display_as].size
                rescue
                    k.to_s.size
                end
            end

            result.keys.each do |k|
                # get all the output fields nicely lined up with a
                # 3 space front padding
                begin
                    display_as = ddl[:output][k][:display_as]
                rescue
                    display_as = k.to_s
                end

                display_length = display_as.size
                padding = lengths.max - display_length + 3
                result_text << " " * padding

                result_text << "#{display_as}:"

                if result[k].is_a?(String) || result[k].is_a?(Numeric)
                    result_text << " #{result[k]}\n"
                else
                    padding = " " * (lengths.max + 5)
                    result_text << " " << result[k].pretty_inspect.split("\n").join("\n" << padding) << "\n"
                end
            end
        else
            result_text << "\n\t" + result.pretty_inspect.split("\n").join("\n\t")
        end
    end

    result_text << "\n"
    result_text
end