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ϓϩΛࢦ͢ਓͷͨΊͷྫ֎ॲཧʢ࠶ʣೖ
ҏ౻३Ұ (@jnchito)
2018.01.13 ୈ80ճ Rubyؔ ษڧձ
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About Me
• ҏ౻३Ұ
• RailsϓϩάϥϚ@SonicGarden
• ϦϞʔτϫʔΧʔ
• Ϊλʔ͖
• Blog: give IT a try
• Twitter: @jnchito
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ฌݿݝࢢࡏॅʢग़େࡕ๛தࢢʣ
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everyday Rails
RSpecʹΑΔRails
ςετೖ
Rails 5.1 + RSpec 3.6ʹ
ۙΞοϓσʔτ༧ఆʂ
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ϓϩΛࢦ͢ਓͷ
ͨΊͷRubyೖ
ධൃചதʂʂ
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ࠓ͓͢͠Δ͜ͱ
• ྫ֎ͱྫ֎ॲཧʹ͍͓ͭͯ͞Β͍
• ຊʹ͋ͬͨා͍
• ྫ֎ॲཧͷόουϓϥΫςΟεˍϕετϓϥΫςΟε
• ྫ֎ॲཧʢओʹઃܭʣʹؔ͢ΔߴͳτϐοΫ
• ۀΤϥʔͱγεςϜΤϥʔͷҧ͍
• ྫ֎ॲཧͱϩʔϧόοΫͷؔ
• ߈Ίͷྫ֎ʢҙਤతʹྫ֎Λൃੜͤ͞Δʣ
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ྫ֎ͱྫ֎ॲཧʹ͍͓ͭͯ͞Β͍
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ྫ֎ͱྫ֎ॲཧʹ͍͓ͭͯ͞Β͍
• ྫ֎(Exception)ͱ
• ͦΕҎ্ϓϩάϥϜΛଓߦͰ͖ͳ͍ྫ֎తͳঢ়گ
• ࡶʹݴ͑ϓϩάϥϜͷΤϥʔ
• ྫ֎ॲཧͱ
• ൃੜͨ͠ྫ֎Λదʹॲཧ͢Δ͜ͱ
• ΤϥʔͱແԑͰ͍ΒΕΔϓϩάϥϜͳ͍
• Αͬͯਖ਼͍͠ྫ֎ॲཧΛֶͿ͜ͱඇৗʹॏཁ
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Rubyʹ͓͚Δྫ֎ॲཧͷجຊߏจ
begin
# Τϥʔ͕ൃੜ͢Δ͔͠Εͳ͍ॲཧ
a = 1 / 0
rescue => e
# Τϥʔ͕ى͖ͨ߹ͷॲཧ
puts "Τϥʔ͕ൃੜ͠·ͨ͠: #{e.message}”
end
# ϝιουશମ͕ྫ֎ॲཧͷରʹͳΔ߹begin/endΛলུͰ͖Δ
def some_method
1 / 0
rescue ZeroDivisionError => e
puts "ZeroDivisionError͕ൃੜ͠·ͨ͠: #{e.message}"
end
# ্ͷίʔυͱԼͷίʔυಉ͡
def some_method
begin
1 / 0
rescue ZeroDivisionError => e
puts "ZeroDivisionError͕ൃੜ͠·ͨ͠: #{e.message}"
end
end
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ͨͩ͠ɺ͜ΕͰऴΘΔͱ͍
• ʮϋϯϚʔΛ࣋ͭਓʹ͕ͯ͢ఝʹݟ͑Δʯ
• ྫ֎ॲཧΛ֮͑ͨਓྫ֎ॲཧΛ͍ͨ͘ͳΔ
• Τϥʔ͕ى͖ͨΒrescue͢Ε͍͍ͱצҧ͍͢Δ
• ͋ͬͪͬͪ͜ʹbegin/rescueΛຒΊࠐΉ
• ʮΤϥʔʹڧ͍ϓϩάϥϜ͕Ͱ͖ͨYOʂʘ(^O^)ʗʯ
• Ͱ͋Γ·ͤΜʂʂ!
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ຊʹ͋ͬͨා͍
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ຊʹ͋ͬͨා͍ʢલ৬Ͱͷମݧஊʣ
• ͱ͋ΔWebγεςϜʢࣾγεςϜʣΛड͚ܧ͍ͩ
• ͦͷγεςϜͳ͘ಈ͍͍ͯͨʢΑ͏ʹݟ͑ͨʣ
• γεςϜվमͷͨΊݱͷਓͱ͢ػձΛͬͨ
• ݱͷਓͷ͍ํΛݟͤͯΒͬͨ
• อଘϘλϯΛΫϦοΫˠʮγεςϜΤϥʔ: -1ʯ
• ʮ͑ͬɺԿ͜Εʁʯ
• ݱͷਓʮ͜Ε͕ग़ͨΒϘλϯΛ࠶ΫϦοΫ͠·͢ʯ
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Πϝʔδతʹ͜͏ʢ࣮ࡍASP.NETʣ
• Τϥʔ͕ൃੜͨ͠ΒΤϥʔίʔυΛදࣔͯ͠ऴΘΓ
• ௨͞Εͳ͍ɺϩάʹ·ͬͨ͘ใ͕Βͳ͍
• ݱʮΤϥʔ͕ग़ͨΒ࠶ΫϦοΫʯΛϚχϡΞϧԽ
• ͦͷޙͷௐࠪˠઃܭϛεͰσουϩοΫ͕සൃͯͨ͠
def create
@post = Post.new(post_params)
@post.save!
redirect_to post_path(@post)
rescue => e
flash.now[:alert] = "γεςϜΤϥʔ: #{e.error_code}"
render action: :new
end
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ଞʹ͜Μͳͷͱ͔ʢ࣮ࡍC#ʣ
class PostService
def find_data(id)
# औಘͨ͠σʔλͳ͔ͥΠϯελϯεมʹηοτ͞ΕΔ
@data = Post.find(id)
# ޭ·ࣦͨഊΛͰฦ͢
return 1
rescue => e
# Τϥʔ͕ى͖ͨΒϝοηʔδ͚ͩ֨ೲͯ͠0Λฦ͢
@error_message = e.message
return 0
end
def save_data(data)
# ΄͔ͷϝιουಉ͡Α͏ͳྫ֎ॲཧ͕ॻ͔Ε͍ͯΔ
end
end
# ҰԠΓड͚औΔ͕ɺ1͔0ͷνΣοΫ͠ͳ͍
ret = post_service.find_data(id)
# Կߟ͑ͣʹσʔλΛऔͬͯ͘Δ
post = post_service.data
# औಘʹࣦഊͨ͠ΒpostnilͳͷͰɺ͜͜ͰΤϥʔ͕ى͖Δ
title = post.title
☠
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͜ͷ݅ͷڭ܇ͱྫ֎ॲཧͷجຊతͳߟ͑ํ
• ྫ֎ॲཧ͍ํΛؒҧ͑Δͱɺͷํ͕େ͖͘ͳΔ
• Ͱ͖Δ͜ͱͱɺ͍͍ͬͯ͜ͱҟͳΔ
• ྫ֎ॲཧͷجຊతͳߟ͑ํ
• ૉਓrescue͢Μͳʂʂ
• Τϥʔ͕ग़ͨΒͦ͜ͰʓͶʂʂ
• ྫ֎ॲཧϑϨʔϜϫʔΫͷڞ௨ॲཧʹ·͔ͤΖʂʂ
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ྫ֎ॲཧΛͬͯڐ͞ΕΔέʔεɾͦͷ1
• ଞͷؒΛಓͮΕʹͨ͘͠ͳ͍߹
# ෳͷϢʔβʔʹҰׅͰϝʔϧΛૹ৴͢Δ
users.each do |user|
begin
# ଞͷϢʔβʔΛಓͮΕʹ͠ͳ͍Α͏ɺΤϥʔ͕ى͖ͯଓߦ͢Δ
send_mail_to(user)
rescue => e
puts "#{e.class}: #{e.message}"
puts e.backtrace
end
end
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ྫ֎ॲཧΛͬͯڐ͞ΕΔέʔεɾͦͷ2
• ྫ֎ͷ༗ແͰ͔͠ཁ݅Λຬͨͤͳ͍߹
require 'json'
def valid_json_format?(text)
# ࣮ࡍʹύʔεͯ͠Τϥʔ͕ൃੜ͢Δ͔Ͳ͏͔νΣοΫ͢Δ͔͠ͳ͍
JSON.parse(text)
true
rescue JSON::ParserError
false
end
valid_json_format?('{ "a": 1 }') #=> true
valid_json_format?('{ "a": 1') #=> false
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ྫ֎ॲཧͷόουϓϥΫςΟε☠
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1. ྫ֎ͷѲΓͭͿ͠☠
• ୭Τϥʔʹؾ͔ͮͳ͍ɺ͋ͱͰௐࠪͰ͖ͳ͍
• ্ͷྫۃ͕ͩɺ݁Ռతʹແࢹ͞ΕΔ߹͋Δ
• Γ͕ແࢹ͞Εͨ߹ͳͲ
user = build_user(data)
# ൃੜͨ͠Τϥʔશʹແࢹ͞ΕΔ
begin
save(user)
rescue
end
# Կࣄͳ͔͔ͬͨͷΑ͏ʹॲཧΛଓߦ
send_mail_to(user)
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2. ExceptionΫϥεΛrescue͍ͯ͠Δ☠
• StandardErrorҎԼΛัଊ͢Δͷ͕ਖ਼ղ
begin
save(user)
rescue Exception => e
# ԿΒ͔ͷΤϥʔॲཧ
end
ϓϩΛࢦ͢ਓͷͨΊͷRubyೖ
ୈ9ষʹొ͢Δਤ
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ࢀߟ
# ໌ࣔతʹStandardErrorΛࢦఆ͢Δ
begin
save(user)
rescue StandardError => e
# ԿΒ͔ͷΤϥʔॲཧ
end
# ྫ֎ΫϥεΛࢦఆ͠ͳ͚ΕStandardErrorͱͦͷαϒΫϥε͕rescue͞ΕΔ
begin
save(user)
rescue => e
# ԿΒ͔ͷΤϥʔॲཧ
end
• ্ͷ2͍ͭͬͯΔ͜ͱಉ͡
• ͳͷͰɺԼͷΑ͏ʹStandardErrorলུ͢Εྑ͍
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3-1. begin͔Βrescue·Ͱͷൣғ͕ແବʹ͍☠
• Ͳ͜Ͱൃੜ͢ΔΤϥʔΛัଊ͍ͨ͠ͷ͔Θ͔Βͳ͍
# ฏͷจࣈྻΛDateΦϒδΣΫτʹม͢Δ
def convert_heisei_to_date(heisei_text)
begin
m = heisei_text.match(/ฏ(?\d+)(?\d+)݄(?\d+)/)
year = m[:jp_year].to_i + 1988
month = m[:month].to_i
day = m[:day].to_i
Date.new(year, month, day)
rescue
# ྫ֎͕ى͖ͨΒʢʹແޮͳ͕͞ΕͨΒʣnilΛฦ͍ͨ͠
nil
end
end
}
{
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3-2. rescueઅʹྫ֎ΫϥεΛԿࢦఆ͠ͳ͍☠
• λΠϓϛε͕ݪҼͰൃੜͨ͠ྫ֎ัଊ͞Εͯ͠·͏
# ฏͷจࣈྻΛDateΦϒδΣΫτʹม͢Δ
def convert_heisei_to_date(heisei_text)
begin
m = heisei_text.match(/ฏ(?\d+)(?\d+)݄(?\d+)/)
year = m[:jp_year].to_i + 1988
month = m[:month].to_i
day = m[:day].to_i
Date.new(year, month, day)
rescue
# ྫ֎͕ى͖ͨΒʢʹແޮͳ͕͞ΕͨΒʣnilΛฦ͍ͨ͠
nil
end
end
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4. ྫ֎ॲཧΛςετ͠ͳ͍☠
• ؊৺ͷຊ൪ڥͰॳΊͯྫ֎ॲཧͷόάʹؾͮ͘
• ͱͱൃੜ͍ͯͨ͠ΤϥʔͷݪҼ͕ࣦΘΕͯ͠·͏
• લ৬Ͱܦݧ͋ΓʢҾ͖ܧ͍ͩγεςϜͰɾɾɾʣ
def some_method
1 / 0
rescue => e
# messageͱॻͭ͘Γ͕mesageͱॻ͍ͯ͠·ͬͨ
puts "Τϥʔ͕ൃੜ͠·ͨ͠: #{e.mesage}"
puts e.backtrace
end
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ωοτͷهࣄʹཁҙ
• όουϓϥΫςΟεΛհ͍ͯ͠Δهࣄଟ͍
• ͦΜͳهࣄͰάάͬͨͱ͖ʹ্Ґʹग़͖ͯͯ͠·͏
• ExceptionΛrescueͯ͠Δهࣄͱ͔ɺΑ͘ݟ͔͚Δ
• ͦΜͳهࣄΛӏವΈʹ͠ͳ͍Α͏ʹʂ
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ྫ֎ॲཧͷϕετϓϥΫςΟε
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1. ݪଇͱͯ͠rescue͠ͳ͍
• ྫ֎ॲཧͷجຊతͳߟ͑ํʢ࠶ܝʣ
• ૉਓrescue͢Μͳʂʂ
• Τϥʔ͕ग़ͨΒͦ͜ͰʓͶʂʂ
• ྫ֎ॲཧϑϨʔϜϫʔΫͷڞ௨ॲཧʹ·͔ͤΖʂʂ
• Ҏ߱rescue͕Ͳ͏ͯ͠ඞཁͳঢ়گΛఆ
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2. ྫ֎ͷใΛϩάʹ͢ˍ௨͢Δ
• ྫ֎Ϋϥε໊ɺϝοηʔδɺόοΫτϨʔεΛϩάग़ྗ
• BugsnagRollbarɺErrbitͳͲͰ։ൃऀʹ௨͢Δ
• Τϥʔʹ͙͢ؾ͖ͮɺ͙͢ௐࠪͰ͖ΔΑ͏ʹ͢Δ
begin
save(user)
rescue => e
# ϩάʹ͢
logger.error "#{e.class} / #{e.message}"
logger.error e.backtrace.join("\n")
# ௨͢Δ
Bugsnag.notify(e)
end
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3. ྫ֎ॲཧͷରൣғͱରΫϥεΛߜΓࠐΉ
• ัଊ͍ͨ͠Τϥʔ͚ͩΛ࣮֬ʹૂ͍ܸͪ͢Δ
• ͦΕҎ֎ͷΤϥʔ͕ग़ͨΒଈɺҟৗऴྃͤ͞Δ
def convert_heisei_to_date(heisei_text)
m = heisei_text.match(/ฏ(?\d+)(?\d+)݄(?\d+)/)
year = m[:jp_year].to_i + 1988
month = m[:month].to_i
day = m[:day].to_i
# ྫ֎ॲཧͷൣғΛڱΊɺัଊ͢Δྫ֎ΫϥεΛݶఆ͢Δ
begin
Date.new(year, month, day)
rescue ArgumentError
# ແޮͳͰ͋ΕnilΛฦ͢
nil
end
end
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ࢀߟ
• ྫ֎ॲཧΛΘͣʹࡁΉํ๏͕͋ΕͦΕΛ͏͖
def convert_heisei_to_date(heisei_text)
m = heisei_text.match(/ฏ(?\d+)(?\d+)݄(?\d+)/)
year = m[:jp_year].to_i + 1988
month = m[:month].to_i
day = m[:day].to_i
# ྫ֎ॲཧͰͳ͘ɺ݅ذΛ͏
if Date.valid_date?(year, month, day)
Date.new(year, month, day)
end
end
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4. ྫ֎ॲཧςετ͢Δ
• ྫ֎ॲཧͷڍಈΛ֬ೝͰ͖ΔςετίʔυΛॻ͘
• ࠶ݱ͕͍͠߹ϞοΫΛ׆༻͢Δ
def some_method
1 / 0
rescue => e
puts "Τϥʔ͕ൃੜ͠·ͨ͠: #{e.message}"
puts e.backtrace
end
class SampleTest < Minitest::Test
def test_some_method
assert_output /Τϥʔ͕ൃੜ͠·ͨ͠/ do
some_method
end
end
end
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ྫ֎ॲཧʢओʹઃܭʣʹؔ͢ΔߴͳτϐοΫ
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1. ۀΤϥʔͱγεςϜΤϥʔͷҧ͍
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Τϥʔʹ2छྨͷΤϥʔ͕͋Δ
• ۀΤϥʔʢϏδωεྫ֎ʣ
• ೖྗϑΥʔϜʹ͓͚ΔϢʔβʔͷೖྗϛε
• ݖݶҧʢݖݶͷͳ͍ϖʔδͷΞΫηεʣ
• γεςϜΤϥʔʢٕज़తྫ֎ʣ
• ϓϩάϥϜͷϛεʢ͍ΘΏΔόάʣ
• ωοτϫʔΫΤϥʔɺσʔλϕʔεͷμϯ
• ։ൃऀ͜ͷ۠ผΛ͚ͳͯ͘ͳΒͳ͍
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ۀΤϥʔͷରॲʢը໘ઃܭʣ
• ϢʔβʔʹΓͤ͠͞Δʢ͓લ͕ѱ͍ͱ͑Δʣ
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ۀΤϥʔͷରॲʢ෦ઃܭɾͦͷ1ʣ
• ྫ֎ॲཧݪଇͱͯ͠Θͳ͍
• ޭ or ࣦഊϝιουͷΓͰදݱ͢Δ
• ݺͼग़͠ଆඞͣΓΛݕূ͢Δ
def create
@event = Event.new(event_params)
# saveϝιουͷΓΛνΣοΫ
if @event.save
# Γ͕trueͳͷͰޭ
redirect_to @event, notice: 'Event was successfully created.'
else
# Γ͕falseͳͷͰࣦഊ
render :new
end
end
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ۀΤϥʔͷରॲʢ෦ઃܭɾͦͷ2ʣ
• ෆඞཁʹྫ֎ॲཧΛΘͳ͍͜ͱ
• ྫ֎ॲཧΛͳͯ͘͠ۀΤϥʔʹରॲͰ͖Δ͔ʁ
• NOͳΒॲཧϑϩʔͷ੍ޚʹྫ֎ॲཧΛ͍ͬͯΔ
# ϓϩδΣΫτͷશؔऀʹରͯ͠కΊΓͷมߋΛࢼΈΔϝιου
def extend_deadline_for_all_stakeholders(project, new_deadline)
project.developers.each do |developer|
developer.update!(deadline: new_deadline)
end
project.customer.update!(deadline: new_deadline)
project.manager.update!(deadline: new_deadline)
true
rescue ActiveRecord::RecordInvalid
# ۀΤϥʔͳͷʹྫ֎ॲཧΛ͍ͬͯΔʢNGʣ
false
end
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ࢀߟ
• ྫ֎ॲཧΛΘͣʹ࣮͢Δ߹ͷίʔυྫ
def extend_deadline_for_all_stakeholders(project, new_deadline)
all_success = true
project.developers.each do |developer|
all_success &= developer.update(deadline: new_deadline)
end
all_success &= project.customer.update(deadline: new_deadline)
all_success &= project.manager.update(deadline: new_deadline)
# ্ͷॲཧͰ1ͭͰfalse͕ฦΕɺall_successfalseʹมΘΔ
# ʢຊདྷσʔλϕʔετϥϯβΫγϣϯͷϩʔϧόοΫߟྀ͖͢ɻৄࡉޙड़ʣ
all_success
end
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γεςϜΤϥʔͷରॲʢը໘ઃܭʣ
• ͝ΊΜɺͬͪ͜Ͱରॲ͢Δ͔Βͬͯͯɺͱ͑Δ
• ͍ΘΏΔ500Τϥʔը໘Λදࣔ͢Δ
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γεςϜΤϥʔͷରॲʢ෦ઃܭʣ
• ݪଇԿ͠ͳ͍
• ଈ࠲ʹۓٸఀࢭͤ͞ɺڞ௨ॲཧʹ·͔ͤΔ
• ΉΛಘͳ͍߹ͷΈɺrescueͯ͠ଓߦ͢Δ
• ͪΖΜϩάग़ྗ௨ඞਢʂ
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2. ྫ֎ॲཧͱϩʔϧόοΫͷؔ
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ྫ֎ॲཧͱϩʔϧόοΫͷؔ
• ʮΞτϛοΫૢ࡞Կ͔ʯΛৗʹҙࣝ͢Δ
• ΞτϛοΫૢ࡞ʢෆՄૢ࡞ʣͱ
• શͯͷมߋ͕ޭͨ͠ͱ͖ͷΈɺมߋΛ֬ఆ
• 1ͭͰࣦഊ͢Εશ෦ΩϟϯηϧʢϩʔϧόοΫʣ
• ྫ
• ෳͷϨίʔυΛಉ࣌ʹߋ৽͢Δ߹
• σʔλϕʔεߋ৽ޙʹ՝ܾۚࡁAPIΛݺͼग़͢߹
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RailsͰෳͷϨίʔυΛಉ࣌ʹߋ৽͢Δ߹
• transactionϝιουͱRollbackྫ֎Λ׆༻͢Δ
• γεςϜΤϥʔ͕ى͖ͨΒͦ͜ͰϩʔϧόοΫ
• ۀΤϥʔͳΒRollbackྫ֎Ͱ໌ࣔతʹϩʔϧόοΫ
def extend_deadline_for_all_stakeholders(project, new_deadline)
all_success = true
transaction do
project.developers.each do |developer|
all_success &= developer.update(deadline: new_deadline)
end
all_success &= project.customer.update(deadline: new_deadline)
all_success &= project.manager.update(deadline: new_deadline)
unless all_success
# ໌ࣔతʹϩʔϧόοΫͤ͞Δʢtransactionϝιου͕rescue͢ΔͷͰॲཧଓߦ͞ΕΔʣ
raise ActiveRecord::Rollback
end
end
all_success
end
]
[
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3. ߈Ίͷྫ֎ʢҙਤతʹྫ֎Λൃੜͤ͞Δʣ
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߈Ίͷྫ֎ ͦͷ1: ༧ظͤ͵݅ذΛ͢
• ༧ظͤ͵݅ذʹೖͬͨΒྫ֎Λൃੜͤ͞Δ
• ࢮ͵ͣͷϓϩάϥϜΛແཧʹੜ͔͍͚ͯ͠ͳ͍
# elseʹೖͬͨΒྫ֎Λൃੜͤ͞Δύλʔϯʢྑ͍ྫʣ
def currency_of(country)
case country
when :japan
'yen'
when :us
'dollar'
when :india
'rupee'
else
raise ArgumentError, "ແޮͳࠃ໊Ͱ͢ɻ#{country}"
end
end
# ྫ֎͕ൃੜ͢Δ
currency_of(:italy) #=> ArgumentError: ແޮͳࠃ໊Ͱ͢ɻitaly
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ࢀߟ: ࢮ͵ͣͳͷʹɺࢮͳͳ͍έʔεɾͦͷ1
• else͕ͳ͍ → nil͕ฦͬͯ͠·͏
# elseΛ༻ҙ͠ͳ͍ύλʔϯʢྑ͘ͳ͍ྫʣ
def currency_of(country)
case country
when :japan
'yen'
when :us
'dollar'
when :india
'rupee'
end
end
# ఆ֎ͷࠃ໊Λ͢ͱnil͕ฦΔ
currency = currency_of(:italy)
#=> nil
# ༧ظͤ͵λΠϛϯάͰΤϥʔ͕ൃੜ͢Δ
currency.upcase
#=> NoMethodError: undefined method `upcase' for nil:NilClass
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ࢀߟ: ࢮ͵ͣͳͷʹɺࢮͳͳ͍έʔεɾͦͷ2
• elseͰಛఆͷΛฦ͢ → ໃ६͕ͨ͠ฦͬͯ͠·͏
# elseΛ:indiaͱͯ͠ѻ͏ύλʔϯʢྑ͘ͳ͍ྫʣ
def currency_of(country)
case country
when :japan
'yen'
when :us
'dollar'
else
'rupee'
end
end
# ໃ६͕ͨ͠ฦ͖ͬͯͯ͠·͏
country = :italy
currency = currency_of(country)
#=> “rupee”
price = 100
"#{country}: #{price}#{currency}"
#=> "italy: 100rupee"
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߈Ίͷྫ֎ ͦͷ2: ͋Γಘͳ͍ΤϥʔʹڧؾͰ
• ۀΤϥʔ͢ΒγεςϜΤϥʔͱݟͳͤΔ߹͋Δ
• ͦ͏͍͏έʔεͰsave!update!Λ͏
• ͨͩ͠ɺΞτϛοΫૢ࡞͚ͩҡ࣋͢ΔΑ͏ʹ
def extend_deadline_for_all_stakeholders(project, new_deadline)
# ສҰͷࣄଶʹඋ͓͑ͯ͘ʢσʔλϕʔεͷมߋΛΞτϛοΫૢ࡞ʹ͢Δʣ
transaction do
# ୭Ұਓͱͯ͠కΊΓͷԆʹจ۟ΛݴΘͳ͍ͣͩʂʢจ۟ΛݴΘΕͨΒγεςϜΤϥʔʣ
project.developers.each do |developer|
developer.update!(deadline: new_deadline)
end
project.customer.update!(deadline: new_deadline)
project.manager.update!(deadline: new_deadline)
end
end
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·ͱΊ
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·ͱΊ: ਖ਼͍͠ྫ֎ॲཧͰͤͳਓੜΛ̇
• ྫ֎ͱྫ֎ॲཧʹ͍͓ͭͯ͞Β͍
• ຊʹ͋ͬͨා͍
• ྫ֎ॲཧͷόουϓϥΫςΟεˍϕετϓϥΫςΟε
• ྫ֎ॲཧʢओʹઃܭʣʹؔ͢ΔߴͳτϐοΫ
• ۀΤϥʔͱγεςϜΤϥʔͷҧ͍
• ྫ֎ॲཧͱϩʔϧόοΫͷؔ
• ߈Ίͷྫ֎ʢҙਤతʹྫ֎Λൃੜͤ͞Δʣ
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ࢀߟจݙ
• .NETͷྫ֎ॲཧ Part.1ʢ@nakama00ɺ2008ʣ
• ྫ֎ઃܭʹ͓͚Δେࡑʢ@t_wadaɺ2012ʣ
• RailsΞϓϦέʔγϣϯʹ͓͚ΔΤϥʔॲཧʢྫ֎ઃܭʣͷߟ͑ํʢ@jnchitoʣ
• give IT a tryʢ@jnchitoʣ
• Nasty design can blast your brain!ʢ20103݄31ʣ
• ٕज़ॻՃͦͷ2ʢ20104݄10ʣ
• and…
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ϓϩΛࢦ͢ਓͷ
ͨΊͷRubyೖ
ୈ9ষ ྫ֎ॲཧΛཧղ͢Δ
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@jnchito
blog.jnito.com
'PMMPXNF