Slide 1
Slide 1 text
Web Application
Good Error Message
(and Bad Error Message)
@moznion
Slide 2
Slide 2 text
@moznion
Slide 3
Slide 3 text
Error Message
Slide 4
Slide 4 text
Error Messageͱ?
- Τϥʔ͕ى͖ͨ࣌ʹग़ͯ͘Δϝοηʔδ
- (جຊతʹ) ਓ͕ؒಡΉ
- ҟৗܥͷॲཧ
- Τϥʔϝοηʔδ͕པΓ……
Slide 5
Slide 5 text
Example
{
"code": "500",
"message": "Internal Server Error"
}
Slide 6
Slide 6 text
Error Messageͷ༻్
- ঢ়گͷද໌
- τϥϒϧγϡʔςΟϯάͷख͕͔Γ
- αʔϏεͷ݈߁ͷࢦඪ
Slide 7
Slide 7 text
Error MessageपΓͷ
- Ͳ͏ॻ͚ྑ͍ͷ͔͍·͍ͪ……
- ޙखʹճΓ͕ͪ……
- ίετ͕……
Slide 8
Slide 8 text
Error Messageͷಛੑ
Slide 9
Slide 9 text
Error Messageͷ࣍ݩ
Slide 10
Slide 10 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
Slide 11
Slide 11 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
ଞͷΤϥʔͱͷ۠ผ
Slide 12
Slide 12 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
Slide 13
Slide 13 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
Կ͕ى͖͍ͯΔ͔ͷఏࣔ
Slide 14
Slide 14 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
Slide 15
Slide 15 text
Error Messageͷ࣍ݩ
1࣍ݩ: Τϥʔίʔυ (ࣝผࢠ)
2࣍ݩ: Τϥʔϝοηʔδ (ঢ়گ)
3࣍ݩ: ϦΧόϦɾ࠶ݱใ (ରॲɾղܾ)
ରॲɾղܾͷख๏ͷఏࣔ
Slide 16
Slide 16 text
Error Messageͷํੑ
Slide 17
Slide 17 text
Error Messageͷํੑ
- ͳͥग़͢ͷ͔
- ԿΛग़͢ͷ͔ (࣍ݩʹؔΘΔ)
- ͍ͭग़͢ͷ͔ (ϩάϨϕϧ)
- Ͳ͜ʹग़͢ͷ͔ (ϩάऩूɼUI)
Slide 18
Slide 18 text
Error Messageͷํੑ
- ͳͥग़͢ͷ͔
- ԿΛग़͢ͷ͔ (࣍ݩʹؔΘΔ)
- ͍ͭग़͢ͷ͔ (ϩάϨϕϧ)
- Ͳ͜ʹग़͢ͷ͔ (ϩάऩूɼUI)
Slide 19
Slide 19 text
Error Messageͷํੑ
- ͳͥग़͢ͷ͔
- ԿΛग़͢ͷ͔ (࣍ݩʹؔΘΔ)
- ͍ͭग़͢ͷ͔ (Ϩϕϧɼྔ)
- Ͳ͜ʹग़͢ͷ͔ (ϩάऩूɼUI)
Slide 20
Slide 20 text
Error Messageͷํੑ
- ͳͥग़͢ͷ͔
- ԿΛग़͢ͷ͔ (࣍ݩʹؔΘΔ)
- ͍ͭग़͢ͷ͔ (Ϩϕϧɼྔ)
- Ͳ͜ʹ (୭ʹ) ग़͢ͷ͔ (ϩάऩूɼUI)
Slide 21
Slide 21 text
Error Messageͷ
ϥΠϑαΠΫϧ
Slide 22
Slide 22 text
- ण໋
- ͦͷͰͷରॲʹར༻
- ଈԠ
- ण໋
- ࠜຊతͳղܾʹར༻
- ϝτϦΫεతʹ
- ͋ͱͰݕࡧͰ͖Δ
Error MessageͷϥΠϑαΠΫϧ
Slide 23
Slide 23 text
- ण໋
- ͦͷͰͷରॲʹར༻
- ଈԠ
- ण໋
- ࠜຊతͳղܾʹར༻
- ϩάɾϝτϦΫεత
- ͋ͱͰݕࡧͰ͖Δ
Error MessageͷϥΠϑαΠΫϧ
Slide 24
Slide 24 text
- ण໋
- ͦͷͰͷରॲʹར༻
- ଈԠ
- ण໋
- ࠜຊతͳղܾʹར༻
- ϩάɾϝτϦΫεత
- ͋ͱͰݕࡧͰ͖Δ
Error MessageͷϥΠϑαΠΫϧ
Slide 25
Slide 25 text
- ण໋
- ͦͷͰͷରॲʹར༻
- ଈԠ
- ण໋
- ࠜຊతͳղܾʹར༻
- ϩάɾϝτϦΫεత
- ͋ͱͰݕࡧͰ͖Δ
Error MessageͷϥΠϑαΠΫϧ
ErrorͷྲྀΛ
ࢹͯ͠alertͱ͔
Slide 26
Slide 26 text
Good Error Message
Slide 27
Slide 27 text
ྑ͍Error Messageͱ?
- Կ͕ى͖͍ͯΔ͔͔Δ (ඞਢ)
- ؆ܿͰ͋Δ͜ͱ (·͍͠)
- ରॲखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
- ղܾखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
Slide 28
Slide 28 text
ྑ͍Error Messageͱ?
- Կ͕ى͖͍ͯΔ͔͔Δ (ඞਢ)
- ؆ܿͰ͋Δ͜ͱ (·͍͠)
- ରॲखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
- ղܾखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
Slide 29
Slide 29 text
"ରॲ"ͱ"ղܾ"ͷҧ͍
Slide 30
Slide 30 text
ղܾ͢ΔͨΊͷError Message
- ࠜຊతͳमਖ਼ͷॿ͚ʹͳΔϝοηʔδ
- e.g. RDBMS͕ग़͢ϝοηʔδ
- ։ൃऀ͚
- ໋ϥΠϑαΠΫϧ
Slide 31
Slide 31 text
ରॲ͢ΔͨΊͷError Message
- ͦͷͰൃੜ͍ͯ͠ΔΛଧ͢Δ
- e.g. ʮωοτϫʔΫྑ͍ͱ͜ΖͰࢼͯ͠ʂʯ
- ղܾʹܨ͕Δ߹͋Δ
- ར༻ऀ͕ετϨεແ͘ιϑτΣΞΛར༻͢Δ
ͨΊͷखॿ͚ => Ϣʔβମݧ
- ։ൃऀɾར༻ऀํ͚
- ໋ϥΠϑαΠΫϧ
Slide 32
Slide 32 text
ྑ͍Error Messageͱ?
- Կ͕ى͖͍ͯΔ͔͔Δ (ඞਢ)
- ؆ܿͰ͋Δ͜ͱ (·͍͠)
- ରॲखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
- ղܾखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
Slide 33
Slide 33 text
Bad Error Message
Slide 34
Slide 34 text
ѱ͍Error Messageͱ
- ·ͬͨ͘ঢ়گ͕Θ͔Βͳ͍
- e.g. "Something wrong!"
- Ͳ͏͢Εྑ͍ͱ͍͏ͷͩ……
- e.g. "Invalid parameter", "Query is too big"
- ใྔ͕ଟ͗͢Δ
- ੌ·͍͡ྔͷstack trace͕ग़Δͱ͔……
- ΫϦεϚεπϦʔݱ
Slide 35
Slide 35 text
ਅͷѱ͍Error Message
Slide 36
Slide 36 text
ਅͷѱ͍Error Message
Error Message͕ແ͍
Slide 37
Slide 37 text
ਅͷѱ͍Error Message
Error Message͕ແ͍
ແ͍ΑΓ͋ͬͨํ͕ྑ͍
Slide 38
Slide 38 text
ࣄྫ
Slide 39
Slide 39 text
Client Side
Slide 40
Slide 40 text
HTTP Status Code
- 1xx, 2xx, 3xx, 4xx, 5xx
- ίʔυʹΑΔ1࣍ݩใ
- (↑ͱ͍͏ͷਖ਼͘͠ͳ͍ɽHTTP Status
CodeʹηϚϯςΟΫε͕͋Δ)
Slide 41
Slide 41 text
- Over HTTPͳrequestͷerror response
- e.g.
{
"code": 1212,
"error": "Not permitted operation"
}
API Response
Slide 42
Slide 42 text
ཧը໘্ͷදࣔ
- ཧը໘ͷૢ࡞தʹΤϥʔ͕ى͖Δ
- ओʹΦϖϨʔλͷਓ͚Έ͍ͨͳ߹
Slide 43
Slide 43 text
ཧը໘্ͷදࣔ
- ཧը໘ͷૢ࡞தʹΤϥʔ͕ى͖Δ
- ओʹΦϖϨʔλͷਓ͚Έ͍ͨͳ߹
Slide 44
Slide 44 text
ཧը໘্ͷදࣔ
- ཧը໘ͷૢ࡞தʹΤϥʔ͕ى͖Δ
- ओʹΦϖϨʔλͷਓ͚Έ͍ͨͳ߹
ଐਓੑͩ...
(ٞ͠·ͤΜ)
Slide 45
Slide 45 text
Facebook Graph API
- APIͷΦʔϓϯϓϥοτϑΥʔϜ
- fbtrace_idʹΑΔΤϥʔใͷఏࣔ&
τϥοΩϯά
Slide 46
Slide 46 text
Server Side
Slide 47
Slide 47 text
Exit status
- `$ echo $?`
- 0ͩͬͨΒޭ
- ͦͷଞࣦഊ (ਈ࢜ڠఆ)
- http://moznion.hatenadiary.com/
entry/2017/06/30/181433
Slide 48
Slide 48 text
୯७ͳError Log
[12:29:14] DBI Exception: DBD::mysql::st execute
failed: Duplicate entry 'XXXXXXXXXXXXXX' for key
'user' [for Statement "INSERT /* ./local/lib/perl5/
Try/Tiny.pm line 77 */ INTO user (id) VALUES (?)" with
ParamValues: 0="XXXXXXXXXXXXXX"] at ./lib/MyApp/Infra/
UserRepository/.pm line 123
Slide 49
Slide 49 text
GitͷError Message
$ git push origin test
To github.com:moznion/sandbox.git
! [rejected] test -> test (non-fast-forward)
error: failed to push some refs to '[email protected]:moznion/
sandbox.git'
hint: Updates were rejected because the tip of your current
branch is behind
hint: its remote counterpart. Integrate the remote changes
(e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help'
for details.
Slide 50
Slide 50 text
·ͱΊ
Slide 51
Slide 51 text
ྑ͍Error Messageͱ?
- Կ͕ى͖͍ͯΔ͔͔Δ (ඞਢ)
- ؆ܿͰ͋Δ͜ͱ (·͍͠)
- ରॲखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
- ղܾखஈ͕ఏҊ͞Ε͍ͯΔ͜ͱ (࠷ߴ)
Slide 52
Slide 52 text
ྑ͍Error MessageΛॻ͘ʹ
- ͳΔ࣍͘ݩͷߴ͍ใΛࣔ͢
- ݟͨਓ͕ٽ͔ͳ͍Α͏ʹ
- తΛ໌֬ʹɼͳΔ͘؆ܿʹ
- ୭͕ݟΔͷ͔ɼԿʹΘΕΔͷ͔
- ͱ͍͑ग़͠ौΒͳ͍
Slide 53
Slide 53 text
ͱ͍͑
- ৗʹ࣍ݩͷߴ͍ΤϥʔϝοηʔδΛॻ͘
ͷ͍͠
- ίετͷ݉Ͷ߹͍
- ݁ہϏδωευϝΠϯΛॻ͔ͳ͍ͱ
Ͳ͏͠Α͏ͳ͍ͷͰ……
Slide 54
Slide 54 text
ίετײͱత
- ৄࡉͳΤϥʔϝοηʔδ͕ग़͢ͱ
ϖΠͰ͖Δ෦खް͘ॻ͘
- ͦ͏͡Όͳ͍ͱ͜ΖͦΕͳΓʹ
(ͱ͍͑ঢ়گ͘Β͍ͪΌΜͱॻ͘)
- ྟػԠมʹ͍ͬͯ͘
Slide 55
Slide 55 text
Q?
Slide 56
Slide 56 text
Misc
Slide 57
Slide 57 text
Error Message༁
Slide 58
Slide 58 text
Error Message༁
- ҃ΔΤϥʔΛʮड͚औΓଆʯʹ;͞Θ͍͠
༰ʹม͢Δ
- e.g. αʔό෦Ͱൃੜͨ͠ΤϥʔΛ
Ϣʔβʹࣔ͢߹
- e.g. ଞͷαʔϏε͔Βड͚औͬͨ
ΤϥʔΛࣗͷจ຺ʹม͢Δ߹
Slide 59
Slide 59 text
Error Message༁
- "SQL Error" => "500 αʔϏεʹ͕ੜ͡
͍ͯ·͢"
- status 5963 => "૬खͷαʔό͕Ωϟύγ
ςΟΦʔόͰࢮΜͰΔʂʂ"
- status code͔Βঢ়گͷจݴʹى͜͢ͳͲ
ͱ͍ͬͨ࣍ݩͷΞηϯγϣϯى͖͕ͪ
Slide 60
Slide 60 text
Stack TraceΛ
Client͚Error Message
ʹಥͬࠐΉ
Slide 61
Slide 61 text
ClientͷError Messageͱͯ͠
Stack traceΛಥͬࠐΉ
- ։ൃ࣌ͷςΫχοΫ (ςΫχοΫ?)
- αʔό͕ྫ֎Λ্͛ͨ࣌ͷελοΫτϨʔ
εΛbodyʹ٧Ίͯ500Λฦ͢
Slide 62
Slide 62 text
ClientͷError Messageͱͯ͠
Stack traceΛಥͬࠐΉ
- Client։ൃऀʮͳΜ͔͓͔͍͠ΜͰ͚͢
ͲʙʯΈ͍ͨͳ࣌ʹελοΫτϨʔεΛ
ͦͷ··ͯ͠Β͑ΔͷͰศར
- ProductionͰdisableʹ͠ΕΔͱ͠͵
Slide 63
Slide 63 text
Q?