Goで作る大量プロセス管理機構

Go Conference'19 Summer in Fukuoka

Transcript

1. (PͰ࡞Δ
   େྔϓϩηε؅ཧػߏ
   
   ໟརܒଠ
   

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2. 
   
   ‣ 'VTJD$P -UE
   ‣ ൃҊऀϓϩμΫτΦʔφʔ
   ‣ *P5ܥͷडୗҊ݅΋
   ‣ (P 3VCZ "84 403"$0.
   ໟརܒଠʢ΋͏Γ͚͍ͨʣ
   

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3. 
   
   

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4. 
   
   ࣗࣾαʔϏε
   

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5. 
   
   ࣗࣾαʔϏε
   डୗ։ൃ
   8FCαΠτ &$αΠτ
   FUD
   ۀ຿ΞϓϦ
   ίϯαϧ "3
   Ϋϥ΢υ
   *P5 'JO5FDI
   "*
   ΠϯλϥΫςΟϒίϯςϯπ εϚϗΞϓϦ
   

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6. ࣗࣾαʔϏε
   डୗ։ൃ
   8FCαΠτ &$αΠτ
   FUD
   ۀ຿ΞϓϦ
   ίϯαϧ "3
   Ϋϥ΢υ
   *P5 'JO5FDI
   "*
   ΠϯλϥΫςΟϒίϯςϯπ εϚϗΞϓϦ
   ύʔτφʔ
   

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7. ࠓ೔͓࿩͍ͨ͜͠ͱ
   

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8. 
   
   ͷલʹʜ
   

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9. ͬͯͳʹʁ
   

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10. 
    
    *P5։ൃऀ޲͚
    ٙࣅσʔλੜ੒αʔϏε
    

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11. 
    
    *P5ͷ࿩
    

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12. 
    
    Ϟϊ͕
    Thing
    

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13. 
    
    Πϯλʔωοτܦ༝Ͱ
    Thing
    

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14. 
    
    αʔόʹσʔλΛૹΓ
    Backend
    Thing
    D a t a
    

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15. 
    
    ղੳͨ͠Γͯ͠
    Backend
    Thing
    D a t a
    
    

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16. 
    
    Կ͔͢Δ
    Backend
    Thing
    D a t a
    
    

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17. 
    
    *P5ͷ࿩
    ͓ΘΓ
    

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18. 
    
    *P5
    ։ൃ͠·͢
    

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19. 
    
    ςετ͍ͨ͠
    Backend
    Thing
    D a t a
    

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20. 
    
    σʔλૹͬͯ΄͍͠
    Backend
    Thing
    D a t a
    

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21. 
    
    Ͱ΋
    

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22. 
    
    Ϟϊʹͩͬͯ
    ౎߹͸͋Δ
    

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23. 
    
    ͑͐ͬɺ
    ։ൃʹ൒೥΋͔͔Δͷʂʁ
    

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24. 
    
    ͑͐ͬɺ
    ϗϯτʹյ͞ͳ͍ͱ
    Τϥʔσʔλग़ͤͳͷʂʁ
    

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25. 
    
    ෛՙࢼݧ༻ʹ୆
    ཉ͍͚͠Ͳʜ
    ݸສԁʂʁ
    

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26. 
    
    ෛՙࢼݧ༻ʹ୆
    ༻ҙ͚ͨ͠Ͳʜ
    ୭͕ૢ࡞͢Δͷ͜Εʂʁ
    

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27. 
    
    ςετʹࠔΔ
    

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28. 
    
    ͦ͏ͩʂ
    

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29. 
    
    γϛϡϨʔλʔΛ࡞Ζ͏ʂ
    Backend
    Simulator
    D a t a
    

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30. 
    
    ΍͹͍ɺ
    ϦϦʔεʹؒʹ߹Θͳ͍ʂ
    

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31. 
    
    ೉͗ͯ͢͠
    ʓʓ͞Μ ࡞ͬͨਓ
    ͔͠
    ಈ͔ͤͳ͍ʜ
    

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32. 
    
    ٱ͠ͿΓʹಈ͔ͨ͠Β
    શવಈ͔ͳ͍ʜ
    

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33. 
    
    ͦ͜Ͱ
    

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34. 
    
    ࢥ͍Ͳ͓ΓʹͳΔϞϊ
    Backend
    D a t a
    

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35. 
    
    ͍ͭͰ΋
    ཉ͍͠σʔλΛ
    ཉ͍͠ྔ͚ͩ
    ૹͬͯ͘ΕΔʂ
    

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36. 
    
    ͏Ε͍͠
    

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37. ը໘Πϝʔδ
    
    
    ࢥ͍௨ΓͷϑΥʔϚοτͰ+40/σʔλΛੜ੒ Ծ૝σόΠεͷεςʔλεͱͦͷมԽΛ೚ҙʹઃఆ
    ͞·͟·ͳ࣌ܥྻσʔλੜ੒ػೳ
    

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38. ͷͬ͘͟Γͨ͠࢓૊Έ
    

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39. 
    
    PublicSubnet PrivateSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    Mock
    Mock
    Mock
    Mock
    Mock
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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40. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    mockૢ࡞JobΛ
    ൃߦ
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    

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41. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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42. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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43. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    mockىಈ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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44. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    Քಇঢ়گɾϩάૹ৴
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    mockىಈ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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45. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    ίϯιʔϧͰ
    mockΛૢ࡞
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    Քಇঢ়گɾϩάૹ৴
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    mockىಈ
    Mock
    Mock
    [ mock ]
    Go੡όΠφϦ͔Βཱͯͨ
    Ծ૝σόΠε໾ϓϩηε
    [ tower ]
    Go੡όΠφϦ͔Βཱͯͨ
    mock؅ཧϓϩηε
    

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46. ࠓ೔͓࿩͍ͨ͜͠ͱ
    վΊͯʂ
    

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47. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    Քಇঢ়گɾϩάૹ৴
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    mockىಈ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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48. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    mockαʔόʔʹ
    ૢ࡞ࢦࣔ
    Քಇঢ়گɾϩάૹ৴
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    ͳΜͰϓϩηεʁ
    ͳΜͰGoʁ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    

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49. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    Քಇঢ়گɾϩάૹ৴
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    ͳΜͰϓϩηεʁ
    ͳΜͰGoʁ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    Ͳ͏΍ͬͯ
    େྔͷϓϩηεΛૢ࡞ʁ
    

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50. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    Քಇঢ়گɾϩάૹ৴
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    ͳΜͰϓϩηεʁ
    ͳΜͰGoʁ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    Ͳ͏΍ͬͯ
    େྔͷϓϩηεΛૢ࡞ʁ
    mockͷࢮ׆؂ࢹ͸
    Ͳ͏ͯ͠Δͷʁ
    ઃఆϑΝΠϧ
    όΠφϦΛDL
    

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51. 
    
    PublicSubnet PrivateSubnet
    DynamoDB
    Lambda
    SNS
    SQS
    S3 Bucket
    (Lot)
    S3 Bucket
    (Binary)
    Web
    Web Worker
    Worker
    mockૢ࡞JobΛ
    ൃߦ
    ઃఆϑΝΠϧΛ
    Ξοϓϩʔυ
    Քಇঢ়گɾϩάૹ৴
    PrivateSubnet
    Mock
    Mock
    Mock
    Mock
    Mock
    Mock
    ͳΜͰϓϩηεʁ
    ͳΜͰGoʁ
    WebίϯιʔϧͰ
    ಈ࡞Λઃఆ
    mockΛૢ࡞
    Ͳ͏΍ͬͯ
    େྔͷϓϩηεΛૢ࡞ʁ
    mockͷࢮ׆؂ࢹ͸
    Ͳ͏ͯ͠Δͷʁ
    όΠφϦͷ
    ߋ৽͸
    Ͳ͏͢Δͷʁ
    

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52. ͳΜͰϓϩηεʁ
    ͳΜͰ(P
    

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53. ‣ NPDLJT
    αʔόʔ߽՚͗͢Δʜ
    ίϯςφएׯ໘౗ͩ͠ɺίϯςφԽ͢Δඞཁ΋ͳ͍
    ϓϩηεͪΐ͏Ͳ͍͍ʂ
    εϨουσόοάେมͦ͏ɺڞ౗Εͦ͠͏
    ͳΜͰϓϩηεʁ
    
    
    

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54. ‣ αʔόʔʹԿ΋Πϯετʔϧͨ͘͠ͳ͍
    ͨͱ͑͹3VCZͩͱ3VCZΛΠϯετʔϧ͢Δඞཁ͕ʜ
    ‣ γϯάϧόΠφϦʹ͢Ε͹ஔ͚ͩ͘Ͱىಈ͕Ͱ͖Δ
    ‣ γϯάϧόΠφϦ͕Ͱ͖Δ΍ͭͰָͦ͠͏ͳͷ
    ‣ ͱ͍͑͹(Pʂ ओ؍
    
    ͳΜͰ(Pʁ
    
    
    

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55. ‣ ίʔυͷن໛ ςετআ͘
    
    NPDL໿ߦ
    UPXFS໿ߦ
    ͪͳΈʹ
    
    
    

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56. େྔNPDLͷૢ࡞
    

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57. ‣ ϑΝΠϧϕʔεͰͷૢ࡞
    ಛఆͷσΟϨΫτϦʹϑΝΠϧΛஔ͔ΕͨͷΛݕ஌ͯ͠ॲཧΛߦ͏
    ૢ࡞͕ඞཁͳ෼͚ͩϑΝΠϧΛஔ͚͹͍͍
    NPDLͷૢ࡞
    
    
    NPDLىಈ NPDLఀࢭ
    ىಈτϦΨʔ

    ϑΝΠϧઃஔ
    tower͕ݕ஌͠
    mockΛىಈ
    ఀࢭτϦΨʔ

    ϑΝΠϧઃஔ
    ֤mock༻
    ఀࢭτϦΨʔ

    ϑΝΠϧઃஔ
    mock͕ݕ஌͠
    ࣗݾফ໓
    

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58. ‣ ݪ࢝త͚ͩͲγϯϓϧͰ৴པੑ΋ߴ͘΍Γ΍͍͢
    Կ΋Πϯετʔϧ͠ͳ͍͍ͯ͘
    ॲཧ͕׬ྃͨ͠ޙʹϑΝΠϧΛফ͢Α͏ʹ͓͚ͯ͠͹ɺ

    ΋͠UPXFS్͕தͰ࠶ىಈͯ͠΋ϑΝΠϧΛݟΕ͹ϨδϡʔϜͰ͖Δ
    ‣ ͦͷଞͷ͔ͬ͜Α͛͞ͳ΍Γํ͸ΊΜͲ͍͘͞ؾ͕͢Δ
    )551αʔόʔ
    1VC4VC2VFVF
    NPDLͷૢ࡞
    
    
    ૹ৴ࣦഊͨ͠ͱ͖ͷ࠶ૹʜ
    ૢ࡞׬ྃલʹUPXFS͕ࢮΜͩ৔߹ʜ
    

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59. ‣ https://github.com/fsnotify/fsnotify
    ‣ ϑΝΠϧมߋݕ஌ϥΠϒϥϦ
    GTOPUJGZ
    
    
    

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60. GTOPUJGZ
    
    
    watcher, err := fsnotify.NewWatcher()
    defer watcher.Close()
    err = watcher.Add("path/to/trigger/directory")
    // ϝΠϯϧʔϓ
    for {
    select {
    case ev := <-watcher.Events:
    // ϑΝΠϧ࡞੒Ҏ֎͸ແࢹ
    if (ev.Op & fsnotify.Create) == 0 {
    continue
    }
    // τϦΨʔϑΝΠϧͷॲཧ
    runTriggerProcessor(ev.Name)
    // Ұ੪ʹmock͕ىಈ͢Δͱड͚ଆ͕େมͳͷͰద੾ʹsleep
    // (ུ)
    case err := <-watcher.Errors:
    // Τϥʔॲཧ
    case //ͦͷଞॾʑͷॲཧ
    }
    }
    

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61. watcher, err := fsnotify.NewWatcher()
    defer watcher.Close()
    err = watcher.Add("path/to/trigger/directory")
    // ϝΠϯϧʔϓ
    for {
    select {
    case ev := <-watcher.Events:
    // ϑΝΠϧ࡞੒Ҏ֎͸ແࢹ
    if (ev.Op & fsnotify.Create) == 0 {
    continue
    }
    // τϦΨʔϑΝΠϧͷॲཧ
    runTriggerProcessor(ev.Name)
    // Ұ੪ʹmock͕ىಈ͢Δͱड͚ଆ͕େมͳͷͰద੾ʹsleep
    // (ུ)
    case err := <-watcher.Errors:
    // Τϥʔॲཧ
    case //ͦͷଞॾʑͷॲཧ
    }
    }
    GTOPUJGZ
    
    
    ؂ࢹର৅ͷσΟϨΫτϦΛઃఆ
    func (w *Watcher) Add(name string) error
    

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62. watcher, err := fsnotify.NewWatcher()
    defer watcher.Close()
    err = watcher.Add("path/to/trigger/directory")
    // ϝΠϯϧʔϓ
    for {
    select {
    case ev := <-watcher.Events:
    // ϑΝΠϧ࡞੒Ҏ֎͸ແࢹ
    if (ev.Op & fsnotify.Create) == 0 {
    continue
    }
    // τϦΨʔϑΝΠϧͷॲཧ
    runTriggerProcessor(ev.Name)
    // Ұ੪ʹmock͕ىಈ͢Δͱड͚ଆ͕େมͳͷͰద੾ʹsleep
    // (ུ)
    case err := <-watcher.Errors:
    // Τϥʔॲཧ
    case //ͦͷଞॾʑͷॲཧ
    }
    }
    GTOPUJGZ
    
    
    ؂ࢹର৅ͷσΟϨΫτϦΛઃఆ
    func (w *Watcher) Add(name string) error
    type Event struct {
    Name string // Πϕϯτ͕͋ͬͨ file/directory
    Op Op // ૢ࡞छผΛද͢Ϗοτྻ
    }
    

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63. GTOPUJGZ
    
    
    watcher, err := fsnotify.NewWatcher()
    defer watcher.Close()
    err = watcher.Add("path/to/trigger/directory")
    // ϝΠϯϧʔϓ
    for {
    select {
    case ev := <-watcher.Events:
    // ϑΝΠϧ࡞੒Ҏ֎͸ແࢹ
    if (ev.Op & fsnotify.Create) == 0 {
    continue
    }
    // τϦΨʔϑΝΠϧͷॲཧ
    runTriggerProcessor(ev.Name)
    // Ұ੪ʹmock͕ىಈ͢Δͱड͚ଆ͕େมͳͷͰద੾ʹsleep
    // (ུ)
    case err := <-watcher.Errors:
    // Τϥʔॲཧ
    case //ͦͷଞॾʑͷॲཧ
    }
    }
    ؂ࢹର৅ͷσΟϨΫτϦΛઃఆ
    func (w *Watcher) Add(name string) error
    ev.OpʹϏοτϚεΫΛ͔͚Δ͜ͱͰૢ࡞छผΛ֬ೝ
    type Op uint32
    const (
    Create Op = 1 << iota
    Write
    Remove
    Rename
    Chmod
    )
    type Event struct {
    Name string // Πϕϯτ͕͋ͬͨ file/directory
    Op Op // ૢ࡞छผΛද͢Ϗοτྻ
    }
    

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64. watcher, err := fsnotify.NewWatcher()
    defer watcher.Close()
    err = watcher.Add("path/to/trigger/directory")
    // ϝΠϯϧʔϓ
    for {
    select {
    case ev := <-watcher.Events:
    // ϑΝΠϧ࡞੒Ҏ֎͸ແࢹ
    if (ev.Op & fsnotify.Create) == 0 {
    continue
    }
    // τϦΨʔϑΝΠϧͷॲཧ
    runTriggerProcessor(ev.Name)
    // Ұ੪ʹmock͕ىಈ͢Δͱड͚ଆ͕େมͳͷͰద੾ʹsleep
    // (ུ)
    case err := <-watcher.Errors:
    // Τϥʔॲཧ
    case //ͦͷଞॾʑͷॲཧ
    }
    }
    GTOPUJGZ
    
    
    ؂ࢹର৅ͷσΟϨΫτϦΛઃఆ
    func (w *Watcher) Add(name string) error
    ev.OpʹϏοτϚεΫΛ͔͚Δ͜ͱͰૢ࡞छผΛ֬ೝ
    type Op uint32
    const (
    Create Op = 1 << iota
    Write
    Remove
    Rename
    Chmod
    )
    type Event struct {
    Name string // Πϕϯτ͕͋ͬͨ file/directory
    Op Op // ૢ࡞छผΛද͢Ϗοτྻ
    }
    sleepೖΕͯ΋ͪΌΜͱશ෦௨஌ͯ͘͠ΕΔͷͰ
    QueueͬΆ͍ײ͡ʹͳΔ
    

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65. NPDLͷࢮ׆؂ࢹ
    

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66. ‣ NPDLఀࢭॲཧͰਖ਼ৗʹఀࢭͰ͖͔ͨ
    NPDL༻ͷఀࢭτϦΨʔϑΝΠϧΛઃஔ
    ࣗવఀࢭ
    w ࠷େՔಇ࣌ؒܦա
    w ఀࢭεςʔλε΁ͷભҠ
    ‣ NPDL͕ҟৗऴ͍ྃͯ͠ͳ͍͔
    NPDL͕ಥવͷࢮΛܴ͑ΔՄೳੑ΋θϩͰ͸ͳ͍
    ద੾ʹݕ஌ɾ௨஌͠ͳ͚Ε͹
    NPDLͷࢮ׆؂ࢹ
    
    
    

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67. ‣ NPDLఀࢭॲཧͰਖ਼ৗʹఀࢭͰ͖͔ͨ
    NPDL༻ͷఀࢭτϦΨʔϑΝΠϧΛઃஔ
    ࣗવఀࢭ
    w ࠷େՔಇ࣌ؒܦա
    w ఀࢭεςʔλε΁ͷભҠ
    ‣ NPDL͕ҟৗऴ͍ྃͯ͠ͳ͍͔
    NPDL͕ಥવͷࢮΛܴ͑ΔՄೳੑ΋θϩͰ͸ͳ͍
    ద੾ʹݕ஌ɾ௨஌͠ͳ͚Ε͹
    NPDLͷࢮ׆؂ࢹ
    
    
    ϓϩηεͷ
    ঢ়ଶมԽΛ؂ࢹ
    

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68. NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    processExitChannel chan int
    func (t *Tower) mockExec(mock MockCode, version string, ...) {
    // ىಈઃఆϑΝΠϧͷऔಘͱ͔(ུ)
    // ϓϩηεىಈ
    var proc *os.Process
    proc, err = os.StartProcess(binPath, args, attr)
    // PidΛอଘ
    mockProcessTable[proc.Pid] = mock
    // goroutineͰऴྃ؂ࢹ
    go func(t *Tower, mock MockCode, pid int) {
    for {
    var status syscall.WaitStatus
    var rusage syscall.Rusage
    wpid, err := syscall.Wait4(pid, &status, syscall.WNOHANG, &rusage)
    if err != nil || (wpid != 0 && status.Exited()) {
    processExitChannel <- pid
    return
    }
    time.Sleep(intervalMsec)
    }
    }(t, mock, proc.Pid)
    

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69. processExitChannel chan int
    func (t *Tower) mockExec(mock MockCode, version string, ...) {
    // ىಈઃఆϑΝΠϧͷऔಘͱ͔(ུ)
    // ϓϩηεىಈ
    var proc *os.Process
    proc, err = os.StartProcess(binPath, args, attr)
    // PidΛอଘ
    mockProcessTable[proc.Pid] = mock
    // goroutineͰऴྃ؂ࢹ
    go func(t *Tower, mock MockCode, pid int) {
    for {
    var status syscall.WaitStatus
    var rusage syscall.Rusage
    wpid, err := syscall.Wait4(pid, &status, syscall.WNOHANG, &rusage)
    if err != nil || (wpid != 0 && status.Exited()) {
    processExitChannel <- pid
    return
    }
    time.Sleep(intervalMsec)
    }
    }(t, mock, proc.Pid)
    NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    ϓϩηεىಈޙɺgoroutineΛ૸Βͤͯ؂ࢹ͢Δ
    (ىಈ͍ͯ͠Δmockͷ਺͚ͩgoroutineΛ૸Β͍ͤͯΔ)
    

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70. NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    processExitChannel chan int
    func (t *Tower) mockExec(mock MockCode, version string, ...) {
    // ىಈઃఆϑΝΠϧͷऔಘͱ͔(ུ)
    // ϓϩηεىಈ
    var proc *os.Process
    proc, err = os.StartProcess(binPath, args, attr)
    // PidΛอଘ
    mockProcessTable[proc.Pid] = mock
    // goroutineͰऴྃ؂ࢹ
    go func(t *Tower, mock MockCode, pid int) {
    for {
    var status syscall.WaitStatus
    var rusage syscall.Rusage
    wpid, err := syscall.Wait4(pid, &status, syscall.WNOHANG, &rusage)
    if err != nil || (wpid != 0 && status.Exited()) {
    processExitChannel <- pid
    return
    }
    time.Sleep(intervalMsec)
    }
    }(t, mock, proc.Pid)
    ϓϩηεىಈޙɺgoroutineΛ૸Βͤͯ؂ࢹ͢Δ
    (ىಈ͍ͯ͠Δmockͷ਺͚ͩgoroutineΛ૸Β͍ͤͯΔ)
    WNOHANGΦϓγϣϯ:
    ঢ়ଶมԽ͕ىͬͨ͜ࢠϓϩηε͕ͳ͍৔߹ʹ͙͢ʹ෮ؼ
    

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71. processExitChannel chan int
    func (t *Tower) mockExec(mock MockCode, version string, ...) {
    // ىಈઃఆϑΝΠϧͷऔಘͱ͔(ུ)
    // ϓϩηεىಈ
    var proc *os.Process
    proc, err = os.StartProcess(binPath, args, attr)
    // PidΛอଘ
    mockProcessTable[proc.Pid] = mock
    // goroutineͰऴྃ؂ࢹ
    go func(t *Tower, mock MockCode, pid int) {
    for {
    var status syscall.WaitStatus
    var rusage syscall.Rusage
    wpid, err := syscall.Wait4(pid, &status, syscall.WNOHANG, &rusage)
    if err != nil || (wpid != 0 && status.Exited()) {
    processExitChannel <- pid
    return
    }
    time.Sleep(intervalMsec)
    }
    }(t, mock, proc.Pid)
    NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    ϓϩηεىಈޙɺgoroutineΛ૸Βͤͯ؂ࢹ͢Δ
    (ىಈ͍ͯ͠Δmockͷ਺͚ͩgoroutineΛ૸Β͍ͤͯΔ)
    WNOHANGΦϓγϣϯ:
    ঢ়ଶมԽ͕ىͬͨ͜ࢠϓϩηε͕ͳ͍৔߹ʹ͙͢ʹ෮ؼ
    status.ExitStatus()Ͱҟৗऴྃ֬ೝ΋ͨ͠Γ͢Δ
    

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72. processExitChannel chan int
    func (t *Tower) mockExec(mock MockCode, version string, ...) {
    // ىಈઃఆϑΝΠϧͷऔಘͱ͔(ུ)
    // ϓϩηεىಈ
    var proc *os.Process
    proc, err = os.StartProcess(binPath, args, attr)
    // PIDΛอଘ
    mockProcessTable[proc.Pid] = mock
    // goroutineͰऴྃ؂ࢹ
    go func(t *Tower, mock MockCode, pid int) {
    for {
    var status syscall.WaitStatus
    var rusage syscall.Rusage
    wpid, err := syscall.Wait4(pid, &status, syscall.WNOHANG, &rusage)
    if err != nil || (wpid != 0 && status.Exited()) {
    processExitChannel <- pid
    return
    }
    time.Sleep(intervalMsec)
    }
    }(t, mock, proc.Pid)
    NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    ϓϩηεىಈޙɺgoroutineΛ૸Βͤͯ؂ࢹ͢Δ
    (ىಈ͍ͯ͠Δmockͷ਺͚ͩgoroutineΛ૸Β͍ͤͯΔ)
    ऴྃͨ͠ΒprocessExitChannelʹ௨஌
    WNOHANGΦϓγϣϯ:
    ঢ়ଶมԽ͕ىͬͨ͜ࢠϓϩηε͕ͳ͍৔߹ʹ͙͢ʹ෮ؼ
    status.ExitStatus()Ͱҟৗऴྃ֬ೝ΋ͨ͠Γ͢Δ
    

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73. NPDLϓϩηεͷঢ়ଶมԽΛ؂ࢹ
    
    
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔
    case pid := <-processExitChannel:
    mock := mockProcessTable[pid]
    // ऴྃޙͷ͓ย෇͚΋Ζ΋Ζ
    delete(mockProcessTable, pid)
    }
    }
    

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74. ‣ NPDLఀࢭॲཧͰਖ਼ৗʹఀࢭͰ͖͔ͨ
    NPDL༻ͷఀࢭτϦΨʔϑΝΠϧΛઃஔ
    ࣗવఀࢭ
    w ࠷େՔಇ࣌ؒܦա
    w ఀࢭεςʔλε΁ͷભҠ
    ‣ NPDL͕ҟৗऴ͍ྃͯ͠ͳ͍͔
    NPDL͕ಥવͷࢮΛܴ͑ΔՄೳੑ΋θϩͰ͸ͳ͍
    ద੾ʹݕ஌ɾ௨஌͠ͳ͚Ε͹
    NPDLͷࢮ׆؂ࢹ
    
    
    ϓϩηεͷ
    ঢ়ଶมԽΛ؂ࢹ
    ఀࢭτϦΨʔϑΝΠϧͱ
    ಈ࡞தͷϓϩηεΛൺֱ
    

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75. ఀࢭτϦΨʔϑΝΠϧͷফԽ֬ೝ
    
    
    ticker := time.NewTicker(tickerIntervalMsec)
    defer ticker.Stop()
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔
    case tickTime := <-ticker.C:
    // τϦΨʔϑΝΠϧ͕͋Δͷʹ࢒͍ͬͯΔϓϩηεΛ֬ೝ
    t.processLeftMock(tickTime)
    }
    }
    func (t *Tower) processLeftMock(cur time.Time) {
    for mock, term := range t.terminateTable {
    if cur.Before(term.triggeredAt.Add(ForceTerminateTime)) {
    continue
    }
    pid, processExist := t.mockTable[mock]
    proc, err := os.FindProcess(pid)
    err = proc.Signal(os.Kill)
    delete(t.terminateTable, mock)
    }
    }
    

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76. ఀࢭτϦΨʔϑΝΠϧͷফԽ֬ೝ
    
    
    ticker := time.NewTicker(tickerIntervalMsec)
    defer ticker.Stop()
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔
    case tickTime := <-ticker.C:
    // τϦΨʔϑΝΠϧ͕͋Δͷʹ࢒͍ͬͯΔϓϩηεΛ֬ೝ
    t.processLeftMock(tickTime)
    }
    }
    func (t *Tower) processLeftMock(cur time.Time) {
    for mock, term := range t.terminateTable {
    if cur.Before(term.triggeredAt.Add(ForceTerminateTime)) {
    continue
    }
    pid, processExist := t.mockTable[mock]
    proc, err := os.FindProcess(pid)
    err = proc.Signal(os.Kill)
    delete(t.terminateTable, mock)
    }
    }
    tickerΛ࢖ͬͯఆظతʹະফԽτϦΨʔϑΝΠϧΛ֬ೝ
    

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77. ఀࢭτϦΨʔϑΝΠϧͷফԽ֬ೝ
    
    
    ticker := time.NewTicker(tickerIntervalMsec)
    defer ticker.Stop()
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔
    case tickTime := <-ticker.C:
    // τϦΨʔϑΝΠϧ͕͋Δͷʹ࢒͍ͬͯΔϓϩηεΛ֬ೝ
    t.processLeftMock(tickTime)
    }
    }
    func (t *Tower) processLeftMock(cur time.Time) {
    for mock, term := range t.terminateTable {
    if cur.Before(term.triggeredAt.Add(ForceTerminateTime)) {
    continue
    }
    pid, processExist := t.mockTable[mock]
    proc, err := os.FindProcess(pid)
    err = proc.Signal(os.Kill)
    delete(t.terminateTable, mock)
    }
    }
    tickerΛ࢖ͬͯఆظతʹະফԽτϦΨʔϑΝΠϧΛ֬ೝ
    ઃஔޙҰఆ͕࣌ؒܦաͨ͠΋ͷͷΈ͕֬ೝର৅
    

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78. ఀࢭτϦΨʔϑΝΠϧͷফԽ֬ೝ
    
    
    ticker := time.NewTicker(tickerIntervalMsec)
    defer ticker.Stop()
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔
    case tickTime := <-ticker.C:
    // τϦΨʔϑΝΠϧ͕͋Δͷʹ࢒͍ͬͯΔϓϩηεΛ֬ೝ
    t.processLeftMock(tickTime)
    }
    }
    func (t *Tower) processLeftMock(cur time.Time) {
    for mock, term := range t.terminateTable {
    if cur.Before(term.triggeredAt.Add(ForceTerminateTime)) {
    continue
    }
    pid, processExist := t.mockTable[mock]
    proc, err := os.FindProcess(pid)
    err = proc.Signal(os.Kill)
    delete(t.terminateTable, mock)
    }
    }
    tickerΛ࢖ͬͯఆظతʹະফԽτϦΨʔϑΝΠϧΛ֬ೝ
    ઃஔޙҰఆ͕࣌ؒܦաͨ͠΋ͷͷΈ͕֬ೝର৅
    ϓϩηεڧ੍ऴྃ
    

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79. όΠφϦͷߋ৽
    

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80. ‣ NPDL
    Քಇத͸ߋ৽ෆཁ ಉ͡ઃఆͰಈ͖ଓ͚ΔͷͰ
    
    ىಈ࣌ʹ࠷৽൛ͷόΠφϦΛ࣋ͬͯ͘Ε͹0,
    ‣ UPXFS
    NPDL͕ՔಇதͰ΋ߋ৽͍ͨ͠
    ࠶ىಈ چUPXFSΛఀࢭ৽UPXFSΛىಈ
    Ͱ͖ΔΑ͏ʹ͓ͯ͘͠
    NPDL؂ࢹঢ়گͷϨδϡʔϜΛ͕Μ͹Δʂ
    όΠφϦͷߋ৽
    
    
    

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81. ‣ ࠶ىಈखॱ
    <چ>UPXFSͷ࠶ىಈτϦΨʔϑΝΠϧͷݕ஌
    <چ>τϦΨʔϑΝΠϧʹॻ͔Ε͍ͯΔόʔδϣϯΛ4͔Β%-ͯ͠ىಈ
    <چ>ऴྃ
    <৽>NPDLͷ؂ࢹঢ়گΛϨδϡʔϜ
    ‣ ϨδϡʔϜ͠ͳ͍ͱ͍͚ͳ͍΋ͷ
    NPDL$PEFͱ1*%Λؔ࿈෇͚ΔNBQ
    NPDLϓϩηεΛ؂ࢹ͢ΔHPSPVUJOF
    UPXFSͷ࠶ىಈ
    
    
    

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82. ࠶ىಈτϦΨʔϑΝΠϧݕ஌dऴྃ
    
    
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔ఆظॲཧͱ͔
    case ev := <-t.towerReboot.Events:
    if (ev.Op & fsnotify.Create) == 0 || (base != towerRebootName) {
    continue
    }
    rebootStrs, err := ioutil.ReadFile(ev.Name)
    reboot := strings.Split(strings.TrimSpace(string(rebootStrs)), " ")
    // ࠶ىಈ࣌ʹόΠφϦ͕ଘࡏ͠ͳ͍৔߹͸μ΢ϯϩʔυͯ͘͠Δ(ུ)
    // ৽towerىಈ
    _, err = os.StartProcess(binPath, args, attr)
    // ϝΠϯϧʔϓ͔Βൈ͚Δ
    return
    }
    }
    

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83. ࠶ىಈτϦΨʔϑΝΠϧݕ஌dऴྃ
    
    
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔ఆظॲཧͱ͔
    case ev := <-t.towerReboot.Events:
    if (ev.Op & fsnotify.Create) == 0 || (base != towerRebootName) {
    continue
    }
    rebootStrs, err := ioutil.ReadFile(ev.Name)
    reboot := strings.Split(strings.TrimSpace(string(rebootStrs)), " ")
    // ࠶ىಈ࣌ʹόΠφϦ͕ଘࡏ͠ͳ͍৔߹͸μ΢ϯϩʔυͯ͘͠Δ(ུ)
    // ৽towerىಈ
    _, err = os.StartProcess(binPath, args, attr)
    // ϝΠϯϧʔϓ͔Βൈ͚Δ
    return
    }
    }
    ࠶ىಈτϦΨʔϑΝΠϧͷ࡞੒ΠϕϯτҎ֎͸ແࢹ
    

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84. ࠶ىಈτϦΨʔϑΝΠϧݕ஌dऴྃ
    
    
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔ఆظॲཧͱ͔
    case ev := <-t.towerReboot.Events:
    if (ev.Op & fsnotify.Create) == 0 || (base != towerRebootName) {
    continue
    }
    rebootStrs, err := ioutil.ReadFile(ev.Name)
    reboot := strings.Split(strings.TrimSpace(string(rebootStrs)), " ")
    // ࠶ىಈ࣌ʹόΠφϦ͕ଘࡏ͠ͳ͍৔߹͸μ΢ϯϩʔυͯ͘͠Δ(ུ)
    // ৽towerىಈ
    _, err = os.StartProcess(binPath, args, attr)
    // ϝΠϯϧʔϓ͔Βൈ͚Δ
    return
    }
    }
    ࠶ىಈτϦΨʔϑΝΠϧͷ࡞੒ΠϕϯτҎ֎͸ແࢹ
    τϦΨʔϑΝΠϧͷத਎ΛݺΜͰόʔδϣϯΛऔಘ
    

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85. ࠶ىಈτϦΨʔϑΝΠϧݕ஌dऴྃ
    
    
    // ϝΠϯϧʔϓ
    for {
    select {
    case // τϦΨʔϑΝΠϧͷݕ஌ॲཧͱ͔ϓϩηεऴྃ࣌ͷॲཧͱ͔ఆظॲཧͱ͔
    case ev := <-t.towerReboot.Events:
    if (ev.Op & fsnotify.Create) == 0 || (base != towerRebootName) {
    continue
    }
    rebootStrs, err := ioutil.ReadFile(ev.Name)
    reboot := strings.Split(strings.TrimSpace(string(rebootStrs)), " ")
    // ࠶ىಈ࣌ʹόΠφϦ͕ଘࡏ͠ͳ͍৔߹͸μ΢ϯϩʔυͯ͘͠Δ(ུ)
    // ৽towerىಈ
    _, err = os.StartProcess(binPath, args, attr)
    // ϝΠϯϧʔϓ͔Βൈ͚Δ
    return
    }
    }
    ࠶ىಈτϦΨʔϑΝΠϧͷ࡞੒ΠϕϯτҎ֎͸ແࢹ
    τϦΨʔϑΝΠϧͷத਎ΛݺΜͰόʔδϣϯΛऔಘ
    ϝΠϯϧʔϓ͔Βൈ͚Δͱͦͷ··ऴྃ
    

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86. NPDL؂ࢹঢ়گͷϨδϡʔϜ
    
    
    func NewTower() *Tower {
    // ͍Ζ͍ΖॳظԽ(ུ)
    // PIDϑΝΠϧΛऔಘ
    pidFiles, err := filepath.Glob(filepath.Join(t.PidsDir(), "mk-*"))
    for _, pidFile := range pidFiles {
    mock := MockCode(filepath.Base(pidFile))
    // PIDϑΝΠϧ͔ΒPIDΛಡΈऔΓ
    pidStr, err := ioutil.ReadFile(pidFile)
    pid, err := strconv.Atoi(strings.TrimSpace(string(pidStr)))
    // PID͔Β࣮ࡍͷϓϩηεΛݟ͚ͭͯอଘ
    proc, err := os.FindProcess(pid)
    t.mockProcessTable[pid] = mock
    // ϓϩηεऴྃ௨஌goroutineΛ௥Ճ
    go func(t *Tower, mock MockCode, pid int) {
    // (ུ)
    }(&t, mock, pid)
    }
    }
    

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87. NPDL؂ࢹঢ়گͷϨδϡʔϜ
    
    
    func NewTower() *Tower {
    // ͍Ζ͍ΖॳظԽ(ུ)
    // PIDϑΝΠϧΛऔಘ
    pidFiles, err := filepath.Glob(filepath.Join(t.PidsDir(), "mk-*"))
    for _, pidFile := range pidFiles {
    mock := MockCode(filepath.Base(pidFile))
    // PIDϑΝΠϧ͔ΒPIDΛಡΈऔΓ
    pidStr, err := ioutil.ReadFile(pidFile)
    pid, err := strconv.Atoi(strings.TrimSpace(string(pidStr)))
    // PID͔Β࣮ࡍͷϓϩηεΛݟ͚ͭͯอଘ
    proc, err := os.FindProcess(pid)
    t.mockProcessTable[pid] = mock
    // ϓϩηεऴྃ௨஌goroutineΛ௥Ճ
    go func(t *Tower, mock MockCode, pid int) {
    // (ུ)
    }(&t, mock, pid)
    }
    }
    ֤mock͸ىಈ࣌ʹPIDϑΝΠϧΛ࡞Δ
    

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88. NPDL؂ࢹঢ়گͷϨδϡʔϜ
    
    
    func NewTower() *Tower {
    // ͍Ζ͍ΖॳظԽ(ུ)
    // PIDϑΝΠϧΛऔಘ
    pidFiles, err := filepath.Glob(filepath.Join(t.PidsDir(), "mk-*"))
    for _, pidFile := range pidFiles {
    mock := MockCode(filepath.Base(pidFile))
    // PIDϑΝΠϧ͔ΒPIDΛಡΈऔΓ
    pidStr, err := ioutil.ReadFile(pidFile)
    pid, err := strconv.Atoi(strings.TrimSpace(string(pidStr)))
    // PID͔Β࣮ࡍͷϓϩηεΛݟ͚ͭͯอଘ
    proc, err := os.FindProcess(pid)
    t.mockProcessTable[pid] = mock
    // ϓϩηεऴྃ௨஌goroutineΛ௥Ճ
    go func(t *Tower, mock MockCode, pid int) {
    // (ུ)
    }(&t, mock, pid)
    }
    }
    ֤mock͸ىಈ࣌ʹPIDϑΝΠϧΛ࡞Δ
    লུͯ͠Δ͚Ͳɺ
    ϓϩηε͕ݟ͔ͭΒͳ͔ͬͨΒPIDϑΝΠϧΛ࡟আ
    

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89. ·ͱΊ
    

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90. ‣ ɹɹʹ͓͍ͯɺ(PΛ࢖ͬͯ

    େྔͷϓϩηεΛͲͷΑ͏ʹ؅ཧ͍ͯ͠Δ͔Λ঺հ
    ͦ΋ͦ΋ͳΜͰϓϩηεʁͳΜͰ(P
    ϑΝΠϧϕʔεͷNPDLૢ࡞
    NPDLͷࢮ׆؂ࢹ
    όΠφϦͷߋ৽
    ‣ ʮ໌೔͔Β࢖͑ΔʯΑ͏ͳ಺༰Ͱ͸ͳ͍͸͚ͣͩͲɺ

    ָ͠ΜͰ΋Β͑ͨͳΒ޾͍Ͱ͢
    ‣ (Pͨͷ͍͠ʂ
    ·ͱΊ
    
    
    

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91. ΛҰॹʹ
    ։ൃͯ͘͠ΕΔ஥ؒΛืूதʂ
    ͝ڵຯ͋Δํ͸ໟར·Ͱʂ
    Go Ruby AWS IoT
    ΋ͬͱ͏·͘΍ΕΔʂ
    ͓΋͠Ζͦ͏ʂ
    @Fukuoka
    

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