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Crystal
in
Operation
Crystal
2018/07/18 Crystal.tokyo #7
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61:+
• ʕ·ᴥ·ʔAKJ )C
@arcage arcage
• =A37.8(/>D &$"
• .80!' 2,95*=A
?
• B/ 0
• ;/ &$"
• & 4
• 6@- %4<#'
2018/07/18 Crystal.tokyo #7
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:6* !.
maillog
)$ #
SMTP AUTH ;/(
IP "
%8
9&0.
-
+,"
'
/)51
23
10742"
1$ 43"
24$ 44"
2018/07/18 Crystal.tokyo #7
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https://crystal-lang.org/api/
2018/07/18 Crystal.tokyo #7
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UTF-8
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IO#set_encoding
#
• #set_encoding
• encoding: ICONV.-"
• invalid: :skip or nil
&)$UTF-8,
• ' / +
File.open("./data.txt") do |file|
# Shift_JIS* 0 %
# (!0
file.set_ecoding("Shift_JIS", :skip)
end
# File.open
#
File.open("./data.txt", "w"
encoding: "Shift_JIS",
invalid: :skip)
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2018/07/18 Crystal.tokyo #7
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File::Info#modification_time
&
0.24File::Stat
•
%
• #ino # ?
• #mtime → #modification_time
• #atime#utime # ?
f_info = File.info("./README.md")
f_info.modification_time
#=> 2018-02-02 05:11:53.379574681 UTC
f_info.permissions
#=> rw-r--r-- (0o644)
f_info.size
#=> 11325_u64
# ! "( inode$)
f_info.same_file?(other_f_info)
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gz
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class Zlib::Reader
gz
•
•
Zlib::Reader
IO
•
require "zlib"
File.open("./maillog.gz") do |file|
Zlib::Reader.open(file) do |gz|
gz.each_line do |line|
# ...
end
end
end
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zip
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class Zip::Reader
zip
•
• !
Zip::Reader::Entry
• Zip /
• #io
require "zip"
Zip::Reader.open("./logs.zip") do |zip|
zip.each_entry do |entry|
entry.io.each_line do |line|
# ...
end
end
end
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method system
• 0
true
• 0 false
system("which", ["cc"])
#=> true
#
system("whic", ["cc"])
#=> false
# (Process::Status)
$?.exit_code
#=> 32512
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method ` ←
•
cc_path = `which cc`
#=> "/usr/bin/cc\n"
#
cc_path = `whic cc`
#=> ""
#
$?.exit_code
#=> 32512
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class Process
•
• #wait
• STDIN/OUT/ERR
prc = Process.new("which", ["cc"])
exit_status = prc.wait
exit_status.exit_code
#=> 0
String.build { |io|
Process.new("which", ["cc"]
output: io).wait
}
#=> "/usr/bin/cc\n"
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ID
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class Process
• ID
•
• CPU
…
•
• kill
Process.pid
#=> 9651
Process.executable_path
#=> "/home/user/bin/exec_file"
Process.times
#=> Process::Tms(@utime=0.0, @stime=0.0,
@cutime=0.0, @cstime=0.0)
Process.find_executable("cc")
#=> "/usr/bin/cc"
Process.kill(6523)
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UNIX
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enum Signal
$ !
!
• #trap do ... end
• #reset
Signal::INT.trap do
# Ctrl+C
"
end
Signal::HUP.trap do
# ! #
end
#
Signal::INT.reset
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module System
CPU Sytem.hostname
#=> "myhost.example.org"
Sytem.cpu_count
#=> 8_u64
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97-I3F
• 8.BG#$ @
• )*6(;&:5 Ruby 90D → Crystal 25D
• =2H % '!%8.4
• crystal run trial & error +C
• 0EA 1C?
,
• "& %-I /
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……
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https://guthub.com/arcage/***
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crystal-logreader
• !
•
tail -F
require "logreader"
log = LogReader.new("/var/log/maillog")
log.each do |line|
#...
end
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ip2country
•
• en/fr/es/de/ja/zh/ko
! /
RIR delegations
umpirsky/country-list
require "ip2country"
ip2c = IP2Country.new
ip2c.lookup("8.8.8.8")
#=> "United Status"
ip2c.lookup("8.8.8.8", "ja")
#=> "
"
ip2c = IP2Country.new("ja")
ip2c.lookup("8.8.8.8")
#=> "
"
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%(
crystal-email
• UTF-8#
• $&
• HTML
• AUTH PLAIN/LOGIN #
• STARTTLS #
• ' concurrent"
Gmail
• Thanks @sdogruyol!
require "email"
EMail.send("smtp.example.org") do
from "[email protected]"
to "[email protected]"
subject ") !"
message "" "
attach "photo.jpg"
end
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crystal-patlite
• PATLITE
• PHN
/ /
//
require "patlite"
ip = "192.169.100.100"
port = 10000
plite = Patlite::PHN.new(ip, port)
plite.set do
green_on
end
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8
#
29
-
+,"
(!
/ *51
10642"
1% 43"
24% 44"
maillog
*% $
SMTP AUTH :/)
IP "
&7
9' 0.
23
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2018/07/18 Crystal.tokyo #7