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GoͰ࣮͢Δ
ܰྔϚʔΫΞοϓݴޠ
ύʔαʔ
id:aereal @ builderscon tokyo 2017
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͢͜ͱ
• ܰྔϚʔΫΞοϓݴޠͱͯͳه๏ʹ͍ͭͯ
• ςΩετॲཧͱύʔαʔδΣωϨʔλʔͷඞཁੑ
• Go/goyaccʹΑΔͯͳه๏ύʔαʔͷհ
• goyaccͷԠ༻ࣝ
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ࣗݾհ
• id:aereal
• GitHub: aereal
• גࣜձࣾͯͳ
ΞϓϦέʔγϣϯΤϯδχΞ
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⚠͓͜ͱΘΓ⚠
• αʔϏεΛ৮͍ͬͯͯײͨ͡
ݸਓతͳ՝ҙࣝʹجͮ͘ϓϥΠϕʔτϫʔΫͰ͢
• αʔϏεʹ࠾༻͞ΕΔ͔ෆ໌
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ࢀߟใ
• http://b.hatena.ne.jp/aereal/2017gokyoto/
• ͯͳϒοΫϚʔΫͰλάΛ͚ͯϒΫϚ͍ͯ͠·͢
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ܰྔϚʔΫΞοϓݴޠͱ
ͯͳه๏
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ܰྔϚʔΫΞοϓݴޠͱ
• LML = Lightweight Markup Language
• HTMLXMLͱϓϨʔϯςΩετͷதؒʹ͋Δ
• Markdown, Textile, ͯͳه๏, etc.
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ܰྔϚʔΫΞοϓݴޠͱ
• LML = Lightweight Markup Language
• HTMLXMLͱϓϨʔϯςΩετͷதؒʹ͋Δ
• Markdown, Textile, ͯͳه๏, etc.
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ͯͳه๏ͱ
• ͯͳ͕ఏڙ͢Δ͍͔ͭ͘ͷαʔϏεͰ͑ΔLML
• ͯͳϒϩάɺͯͳμΠΞϦʔɺetc.
• HTMLʹม͞ΕΔศརͳه๏
• org-modeͱͪΐͬͱࣅ͍ͯΔจ๏
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* ݟग़͠1
** ݟग़͠2
[http://127.0.0.1/:title=΅͘ͷIPͰ͢]
- Ruby
- Perl
- Go
+ ى
+ ঝ
+ స
+ ݁
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࣮͍Ζ͍Ζ
• ͯͳϒϩάɺͯͳμΠΞϦʔɺͯͳάϧʔϓ
• Text-Hatena (CPAN)
• Text-Xatena (CPAN)
• chris4403/WikiTextConverter
• motemen/pandoc
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࣮͍Ζ͍Ζ
• ༷ ≈ ࣮
• ࣮͕͍Ζ͍Ζ͋Δ
• ͭ·Γ
• ࣮ͷ͚༷͕ͩଘࡏ͢Δ
• ༷ΛΔʹPerlͱਖ਼نදݱΛಡΈղ͘ඞཁ͕͋Δ
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खࠒͳ࣮͕ແͯ͘ࠔΔ
• PerlҎ֎Ͱॻ͔ΕͨΞϓϦέʔγϣϯͰ
ͯͳه๏Λ͑ΔΑ͏ʹ͍ͨ͠ɺ͚Ͳ……
• Perlͷ֦ுਖ਼نදݱΛۦ͍ͯ͠ΔͷͰҠ২େม
• HTMLม·ͰΔύʔαʔ͕ଟ͍
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ϙʔλϏϦςΟ
• ϒϥβͰϥΠϒϓϨϏϡʔͱ͔͍ͨ͠͡ΌΜ
• ೖྗʹର͢Δग़ྗ (AST) ͚ͩΛܾΊ͍ͨ
• PerlGoScala, JavaScriptͦͷଞͰॻ͖͍ͨ
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HTMLม·ͰΓͨ͘ͳ͍
• ଟ͘ͷύʔαʔ࣮͕HTMLม·Ͱߦ͏
• ҰํɺೖྗʹͲΕ͘Β͍HTMLΛڐՄ͢Δ͔
αʔϏεຖ (!= ύʔαʔ࣮ຖ) ʹҟͳΔ
• → ύʔαʔͱHTMLมΛ͍ͨ͠
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͜Μͳͯͳه๏ύʔαʔ͕
΄͍͠
• ϦϑΝϨϯεͨΓ͏Δૉͳ࣮
• = ਖ਼نදݱͰͳΜͱ͔͠Α͏ͱ͍͗ͯ͢͠ͳ͍
• ύʔε݁Ռ͕HTMLͰͳ͘தؒදݱ͕ಘΒΕΔ
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ࡾߦͰ·ͱΊΔͱ
• AST͘Ε!!!
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࣍ճ༧ࠂ
• ಛఆͷݴޠʹґଘ͠ͳ͍
ྑ͍͔Μ͡ͷςΩετॲཧάοζͳ͍ͷ͔
• ͨͩ͠ (֦ு) ਖ਼نදݱҎ֎
• Αͦ͞͏ͳςΩετॲཧٕज़Λ୳͠ʹ͍͖·͢
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ςΩετॲཧͱ
ύʔαʔδΣωϨʔλʔ
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ςΩετॲཧͻͱΊ͙Γ
• ςΩετॲཧͷςΫχοΫΛ͍Ζ͍Ζհ
• έʔεʹΑͬͯύʔαʔΛॻ͘·Ͱͳ͔ͬͨΓ͢Δ
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τʔΫϯͷग़ݱҐஔ
"id:aereal".substring(3) // => "aereal"
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τʔΫϯͷग़ݱҐஔ
• τʔΫϯͷग़ݱҐஔ͕ݻఆͳΒ͜Ε͘Β͍Ͱ
• Մมͩͱഁ͢Δ
• ͓ͦͯ͠Αͦͷจ๏ՄมͷτʔΫϯ͔Γ
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ਖ਼نදݱ
/id:(.+)/.match("id:aereal")[1]
// => "aereal"
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ਖ਼نදݱ
• ׅހͷඇରԠݕग़Ͱ͖ͳ͍
• (POSIXͷਖ਼نදݱͰෆՄɺ
Perlͷ֦ுਖ਼نදݱͰͰ͖ͨͣ)
• ҰຊΓ͕Ͱ͖ͳ͔ͬͨΒɺ
ޙड़ͷঢ়ଶཧΛߦ͏ඞཁ͕͋Δ
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ঢ়ଶભҠΛཧ
var isInIdNotation = false;
while (1) {
if (isInIdNotation) {
var name = readText(); // => "aereal"
} else {
switch (readChar()) {
case ':':
isInIdNotation = true;
default:
// ...
}
}
}
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ঢ়ଶભҠΛཧ
var isInIdNotation = false;
var isInHeading = false;
var isInUnorderedList = false;
var isInOrderedList = false;
while (1) {
if (isInIdNotation)
if (isInHeading)
if (isInUnorderedList)
if (isInOrderedList)
}
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No content
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• ͲΕจ๏Λ၆ᛌͮ͠Β͍
• ϞδϡʔϧԽ͕͍͠
• → খ͍͞෦ΛੵΈ্͍͛ͯ͘ελΠϧͰ࡞ΕͨΒ……
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ͦ͜Ͱyacc
• ύʔαʔδΣωϨʔλʔͷ1ͭ
• BNFʹࣅͨߏจنଇ͔ΒύʔαʔΛੜ͢Δ
• ෳͷنଇΛΈ߹Θͤͯ1ͭͷنଇΛ࡞Γ্͛Δ
• ίʔϧόοΫελΠϧͰ
نଇΛϓϩάϥϜʹม͢Δ (ؐݩɺreduce)
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https://tools.ietf.org/html/rfc7230
HTTP-Message = start-line
*( header-field CRLF)
CRLF
[ message-body]
start-line = request-line / status-line
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yacc
• BNFͱ͍͏நతͳํ๏Ͱطड़Ͱ͖Δͷ͕Α͍
• ݴޠDSLʹରͯ͠ϙʔλϏϦςΟͰ༏Δ
• ϨΩαʔ (ࣈ۟ղੳث) ผ్࣮͢Δඞཁ͕͋Δ
• ߏจنଇͷίʔϧόοΫ෦͕
ΤσΟλͰϋΠϥΠτ͞Εͳ͍ (ͳʹ͔͍͍ํ๏͋Γͦ͏)
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࣍ճ༧ࠂ
• yaccΑͦ͞͏ͱ͍͏͜ͱ͕Θ͔ͬͨ
• GoͱyaccΛΈ߹ΘͤΒΕΔͷ͔
• ͨͯͯ͠ͳه๏ύʔαʔΛ࡞Δ͜ͱ͕Ͱ͖Δͷ͔
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https://git.io/v7gcD
github.com/aereal/gohn
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gohn
• Written in Go w/goyacc
• pronounce as `gone`
• ओཁͳه๏࣮ࡁΈ
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gohnͷσβΠϯ
• ඪ४ೖྗ͔Βͯͳه๏Λड͚औΓɺ
• ඪ४ग़ྗʹASTΛJSONʹγϦΞϥΠζͯ͠ग़ྗ͢Δ
• → HTMLͷมผ్࣮͢Δ
• ͱͯUNIXత
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AST
• JSONʹγϦΞϥΠζ
• JSON schemaΛެ։͍ͯ͠Δ
• εΩʔϚ͔ΒHTMLมثΛࣗಈੜ͢Δ͜ͱͰ͖ͦ͏
• https://github.com/aereal/gohn/blob/master/schema.json
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Goͱyacc
• goyaccͱ͍͏πʔϧ͕͋Δ
• go get golang.org/x/tools/cmd/goyacc
• ΞΫγϣϯΛGoͰॻ͚Δ
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Goͱࣈ۟ղੳ
• ࣈ۟ղੳ = ಡΜͩจࣈ͕ͲΜͳҙຯΛ࣋ͭͷ͔ฦ͢
• text/scannerͱ͍͏ඪ४ύοέʔδ͕ศར
• ڍಈΛΧελϚΠζͰ͖Δ
• τʔΫϯΛফඅͨ͠࠷ޙͷҐஔΛهͯ͘͠ΕΔͷͰ
Τϥʔϝοηʔδͷߏஙָ͕
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σϞ
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Ԡ༻ฤ
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HTTPه๏
[http://example.com/]
#
# http://example.com/
#
[http://127.0.0.1/:title=΅͘ͷIP]
#
# ΅͘ͷIP
#
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HTTPه๏
• ΞϯΧʔϦϯΫʹม͞ΕΔه๏
• ඌʹల։࣌ͷΦϓγϣϯΛ `:` ʹଓ͚ͯطड़Ͱ͖Δ
• `:` URLͷҰ෦ʹݱΕΔ͜ͱ͕͋Δ
• → ࣍ͷ1จࣈΛಡΉ͚ͩͰ:titleͷ։͔࢝அͰ͖ͳ͍
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࠷ॳʹݱΕΔ `:` εΩʔϜ෦ͱݟͳͯ͠ແࢹ͢Δ͜ͱʹ
if !l.seenColon {
l.seenColon = true
return false // maybe part of URL
} else {
return true
}
https://github.com/aereal/gohn/blob/master/parser/
lex.go#L100
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࠶ؼతͳϧʔϧ
• N > 1ͷࢠنଇ͔ΒͳΔنଇͷॻ͖ํ
• appendͷॱ൪͚ͩؒҧ͑ͳ͍Α͏ʹ
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http_options:
http_option
{
$$ = []string{$1}
}
| http_option http_options
{
options := $2
$$ = append([]string{$1}, options...)
}
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ςετ
• Table-driven tests͕Φεεϝ
• https://github.com/golang/go/wiki/TableDrivenTests
• lexerΛؚΉparserͷػೳςετ͚ͩͰेͩͱࢥ͏
• https://github.com/aereal/gohn/blob/master/parser/
parser_test.go#L17
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σόοά
• tokenͷࣝผࢠ (int) ͔Β໊લ (string) Λ
ٯҾ͖͢ΔϝιουΛఆ͓ٛͯ͘͠ͱศར
• print͢ΔʹͤΑσόοΨΛ͏ʹͤΑ
• https://github.com/aereal/gohn/blob/master/parser/
lex.go#L29
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·ͱΊ
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Go/goyaccศར
• GoෳࡶͳCLIΛϙʔλϒϧʹ࡞Δͷʹ͍͍ͯΔ
• goyacc (yacc) ෳࡶͳจ๏ͷύʔαʔʹ͍͍ͯΔ
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ܰྔϚʔΫΞοϓݴޠ
͍͠
• ਓؒʹͱͬͯͷಡΈॻ͖͢͠͞ͱ
ػցʹͱͬͯͷಡΈॻ͖͢͠͞ҟͳΔ
• ݫ֨ͳจ๏نଇʹैΘͤΔύʔαʔΑΓ
ޡΓగਖ਼ͯ͘͠ΕΔ΄͏͕࣮༻తͳͷͰ?
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ύʔαʔ࡞Γָ͍͠
• Ͱ͖Δ͜ͱɺΓ͍ͨ͜ͱɺؔ৺ͷ͋Δ͜ͱ͕
͏·͘όϥϯε͞Εͨඪ
• WebͱςΩετॲཧ
• খ͞ͳඪΛগͣͭ͠ੵΈॏͶ͍͚ͯΔ
• ʮࠓϦετه๏ͷ࣮͕Ͱ͖ͨͧʯ
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ڵຯΛ࣋ͬͯ͘Εͨਓ
• ·ͣJSONͷύʔαʔΛॻ͍ͯΈΔͱΑͦ͞͏
• RFC, relaxed JSON, etc. ʹൃలͤͯ͞ΈΔ
• ࣍ࣈ۟ղੳثΛखॻ͖ͯ͠ΈΔ
• ࣍ߏจղੳثखॻ͖ͯ͠ΈΔ
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