Gradle BOM importでライブラリバージョン管理 / DroidKaigi2019

DroidKaigi2019 Day.2 Room3 11:20-11:50（JA / EN 同時通訳）
https://droidkaigi.jp/2019/timetable/70735
https://www.youtube.com/watch?v=bm_szoMkzMo

1. Gradle BOM import Ͱ
 ϥΠϒϥϦόʔδϣϯ؅ཧ Kohei Yamamoto DroidKaigi2019 Day2 11:20-11:50 Room3
2. ҰॠͰΘ͔Δ Gradle BOM import ͰϥΠϒϥϦόʔδϣϯ؅ཧ dependencies { implementation platform('com.squareup.okhttp3:okhttp-bom:3.12.0') implementation 'com.squareup.okhttp3:okhttp' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } dependencies { implementation 'com.squareup.okhttp3:okhttp:3.12.0' implementation 'com.squareup.okhttp3:okhttp-tls:3.12.0' implementation 'com.squareup.okhttp3:okhttp-urlconnection:3.12.0' implementation 'com.squareup.okhttp3:logging-interceptor:3.12.0' testImplementation 'com.squareup.okhttp3:mockwebserver:3.12.0' } ↓
3. Profile Name : Kohei Yamamoto Job : Android Engineer in teamLab GitHub : gyamoto Twitter : farundorl PokemonGo : 3729 7371 0759
5. About teamLab (digital art)
6. About teamLab (digital art)
7. σδλϧΞʔτ͚ͩ͡Όͳͯ͘ɺ \ ࣮͸ŊνʔϜϥϘͬͯ /
8. ΞϓϦ΍WebαʔϏε։ൃ΋ ΍ͬͯ·͢ \ ࣮͸ŊνʔϜϥϘͬͯ /
11. Gradle BOM import ͰϥΠϒϥϦόʔδϣϯ؅ཧ 1. Gradle • Gradle & Android • Dependency Management 2. BOM • Gradle BOM Import • [Q] Version Conflict? • [nits] For Gradle 4.6 • [nits] Dependency Constraint 3. Future • For Library Creator • For Team Develop ?
12. Specification • Android Studio : 3.4 Beta3 • Gradle version : 5.1.1 (and 4.6) • Gradle script : Groovy
13. Ͳ͜·Ͱ
    ϥΠϒϥϦͷόʔδϣϯΛ
    ؅ཧͯ͠·͔͢ʁ
14. Dependency management • ࡢࠓͷΞϓϦ։ൃͰ͸ϥΠϒϥϦΛ࢖͏͜ͱ͕Ұൠత • ϥΠϒϥϦͷଟ͘͸ϦϙδτϦʹϗεςΟϯά͞Ε͍ͯΔ • Gradleܦ༝ͰґଘੑΛղܾͯ͠ɺϩʔΧϧͰ࣮ߦ͍ͯ͠Δ
15. Level1: def xxx_version = '1.2.3' Dependency management dependencies { // Example: Retrofit (HTTP Client Library) implementation 'com.squareup.retrofit2:retrofit:2.5.0' implementation 'com.squareup.retrofit2:adapter-rxjava2:2.5.0' implementation 'com.squareup.retrofit2:converter-moshi:2.5.0' implementation 'com.squareup.retrofit2:retrofit-mock:2.5.0' }
16. Level1: def xxx_version = '1.2.3' Dependency management dependencies { // Example: Retrofit (HTTP Client Library) implementation 'com.squareup.retrofit2:retrofit:2.5.0' implementation 'com.squareup.retrofit2:adapter-rxjava2:2.5.0' implementation 'com.squareup.retrofit2:converter-moshi:2.5.0' implementation 'com.squareup.retrofit2:retrofit-mock:2.5.0' } ~~~~~ ~~~~~ ~~~~~ ~~~~~ '2.5.0' x 4
17. Level1: def xxx_version = '1.2.3' Dependency management dependencies { def retrofit_version = '2.5.0' implementation "com.squareup.retrofit2:retrofit:$retrofit_version" implementation "com.squareup.retrofit2:adapter-rxjava2:$retrofit…" implementation "com.squareup.retrofit2:converter-moshi:$retrofit…" implementation "com.squareup.retrofit2:retrofit-mock:$retrofit…" }
18. dependencies { implementation 'com.google.firebase:firebase-core:16.0.6' implementation 'com.google.firebase:firebase-auth:16.1.0' implementation 'com.google.firebase:firebase-perf:16.2.3' implementation 'com.google.firebase:firebase-storage:16.0.5' implementation 'com.google.firebase:firebase-firestore:18.0.0' implementation 'com.google.firebase:firebase-messaging:17.3.4' } app/build.gradle Level2: def version in ext Dependency management
19. dependencies { implementation 'com.google.firebase:firebase-core:16.0.6' implementation 'com.google.firebase:firebase-auth:16.1.0' implementation 'com.google.firebase:firebase-perf:16.2.3' implementation 'com.google.firebase:firebase-storage:16.0.5' implementation 'com.google.firebase:firebase-firestore:18.0.0' implementation 'com.google.firebase:firebase-messaging:17.3.4' } app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… Level2: def version in ext Dependency management
20. dependencies { implementation 'com.google.firebase:firebase-core:16.0.6' implementation 'com.google.firebase:firebase-auth:16.1.0' implementation 'com.google.firebase:firebase-perf:16.2.3' implementation 'com.google.firebase:firebase-storage:16.0.5' implementation 'com.google.firebase:firebase-firestore:18.0.0' implementation 'com.google.firebase:firebase-messaging:17.3.4' } app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… core: 16.0.6 auth: 16.1.0 pref: 16.2.3 storage: 16.0.5 firestore: 18.0.0 messaging: 17.3.4 16.0.2 15.1.0 16.2.0 16.0.0 17.0.0 17.3.2 16.0.3 16.0.0 16.2.1 16.0.2 17.1.5 17.3.3 15.0.2 15.0.0 16.2.3 15.0.2 16.0.0 17.1.0 Level2: def version in ext Dependency management
21. dependencies { implementation 'com.google.firebase:firebase-core:16.0.6' implementation 'com.google.firebase:firebase-auth:16.1.0' implementation 'com.google.firebase:firebase-perf:16.2.3' implementation 'com.google.firebase:firebase-storage:16.0.5' implementation 'com.google.firebase:firebase-firestore:18.0.0' implementation 'com.google.firebase:firebase-messaging:17.3.4' } app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… core: 16.0.6 auth: 16.1.0 pref: 16.2.3 storage: 16.0.5 firestore: 18.0.0 messaging: 17.3.4 16.0.2 15.1.0 16.2.0 16.0.0 17.0.0 17.3.2 16.0.3 16.0.0 16.2.1 16.0.2 17.1.5 17.3.3 15.0.2 15.0.0 16.2.3 15.0.2 16.0.0 17.1.0 Level2: def version in ext Dependency management
22. ext { kotlin_version = '1.3.20' ... firebase_core_version = '16.0.6' firebase_auth_version = '16.1.0' firebase_pref_version = '16.2.3' firebase_storage_version = '16.0.5' firebase_firestore_version = '18.0.0' firebase_messaging_version = '17.3.4' ... } dependencies.gradle Level2: def version in ext Dependency management
23. dependencies { implementation "com.google.firebase:firebase-core:$..." implementation "com.google.firebase:firebase-auth:$..." implementation "com.google.firebase:firebase-perf:$..." implementation "com.google.firebase:firebase-storage:$..." implementation "com.google.firebase:firebase-firestore:$..." implementation "com.google.firebase:firebase-messaging:$..." } app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… Level2: def version in ext Dependency management
24. app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… Level3: define dependencies in ext Dependency management dependencies { implementation "com.google.firebase:firebase-core:$..."ɹɹɹɹ implementation "com.google.firebase:firebase-auth:$..."ɹɹɹɹ implementation "com.google.firebase:firebase-perf:$..."ɹɹɹɹ implementation "com.google.firebase:firebase-storage:$..." implementation "com.google.firebase:firebase-firestore:$..." implementation "com.google.firebase:firebase-messaging:$..." } Group ID Artifact ID Version
25. ext { versions = [ kotlin : '1.3.20', okhttp : '3.12.1', ] depends = [ kotlin : [ stdlib : "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$versions.kotlin", junit : "org.jetbrains.kotlin:kotlin-test-junit:$versions.kotlin", ], firebase : [ core : 'com.google.firebase:firebase-core:16.0.6', ... ], dependencies.gradle Level3: define dependencies in ext Dependency management
26. Level3: define dependencies in ext Dependency management dependencies { implementation depends.kotlin.stdlib implementation depends.kotlin.junit implementation depends.firebase.core implementation depends.firebase.auth implementation depends.firebase.pref ... } app/build.gradle, foo/build.gradle, bar/build.gradle, piyo/build.gradle, etc… Add level4
27. Level3: define dependencies in ext Dependency management • DroidKaigi/conference-app-2019 • buildSrcʹGroupID, ArtifactID, VersionΛఆٛ • */build.gradle ͔Β `Dep.Kotlin.stdlibJvm` ͷΑ͏ʹࢀর ref: https://github.com/DroidKaigi/conference-app-2019/blob/master/buildSrc/src/main/java/dependencies/Dep.kt 
 ref: https://github.com/DroidKaigi/conference-app-2019/blob/master/frontend/android/build.gradle
28. Ͳ͜·Ͱ
    ϥΠϒϥϦͷόʔδϣϯΛ
    ؅ཧͯ͠·͔͢ʁ
29. Dependency management dependencies { def version = '1.2.3' implementation "group:artifact:$version" } ext { versions = '1.2.3' } dependencies { implementation "group:artifact:$version" } ext { version = '1.2.3' depends = "group.artifact:$version" } dependencies { implementation depends }
30. # Dependency management dependencies { def version = '1.2.3' implementation "group:artifact:$version" } ext { versions = '1.2.3' } dependencies { implementation "group:artifact:$version" } ext { version = '1.2.3' depends = "group.artifact:$version" } dependencies { implementation depends }
31. # Dependency management dependencies { def version = '1.2.3' implementation "group:artifact:$version" } ext { versions = '1.2.3' } dependencies { implementation "group:artifact:$version" } ext { version = '1.2.3' depends = "group.artifact:$version" } dependencies { implementation depends }
32. # Dependency management dependencies { def version = '1.2.3' implementation "group:artifact:$version" } ext { versions = '1.2.3' } dependencies { implementation "group:artifact:$version" } ext { version = '1.2.3' depends = "group.artifact:$version" } dependencies { implementation depends }
33. Dependency management • ͪΌΜͱϥΠϒϥϦͷόʔδϣϯΛ؅ཧ͢Δͷ͸ख͕͔͔ؒΔ • ϥΠϒϥϦͷόʔδϣϯ͕ζϨ͍ͯͯ΋໰୊ͳ͍͜ͱͷํ͕
 ଟ͍͚Ͳɺى͖Δͱ͖͸ى͖Δ… • ඞཁͳ͜ͱͳͷͰ͔ͬ͠Γ΍ͬͯɺ։ൃͷ଍ΛҾͬுΔΑ͏ͳ ͜ͱΛආ͚͍ͨ
34. Gradle \ BOMͷલʹ͓͞Β͍ʂ /
35. Gradle • ΦʔϓϯιʔεͷϏϧυπʔϧ • Groovy or Kotlin DSL • Highly customizable & Fast & Powerful \ Flexible! High Performance! /
36. Gradle & Android • AndroidͷެࣜϏϧυπʔϧͱͯ͠࠾༻ • Android Plugin for GradleʹΑͬͯΞϓϦͷίϯύΠϧɺ ϥΠϒϥϦ/ґଘؔ܎ͷղܾɺςετͷ࣮ߦɺॺ໊ɺ
 ApkͷύοέʔδઃఆͳͲΛఏڙ
37. GradleͰґଘੑͷղܾ Dependency management in Gradle \ ΋ͬͱৄ͘͠ /
38. Dependency management in Gradle android { ... } dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } app/build.gradle
39. Dependency management in Gradle android { ... } dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } app/build.gradle
40. android { ... } dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } app/build.gradle Dependency management in Gradle
41. android { ... } dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } app/build.gradle Dependency management in Gradle
42. (SBEMF
    #VJME dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } Dependency management in Gradle ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle
43. (SBEMF
    #VJME dependencies { // 1. Local binary dependency implementation fileTree(dir: 'libs', include: ['*.jar']) // 2. Dependency on the "core" module from this project implementation project(':core') // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } -PDBM
    'JMF
    3FQPTJUPSZ access artifacts Dependency management in Gradle ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle
44. (SBEMF
    #VJME /FUXPSL dependencies { ... // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' } download artifacts Dependency management in Gradle ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle
45. (SBEMF
    #VJME .BWFO
    3FQPTJUPSZ *WZ
    3FQPTJUPSZ /FUXPSL download artifacts Dependency management in Gradle ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle dependencies { ... // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' }
46. (SBEMF
    #VJME .BWFO
    3FQPTJUPSZ *WZ
    3FQPTJUPSZ /FUXPSL download artifacts Dependency management in Gradle *.module *.pom ivy.xml module metadata ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle dependencies { ... // 3. Remote binary dependency implementation 'androidx.appcompat:appcompat:1.0.2' }
47. (SBEMF
    #VJME .BWFO
    3FQPTJUPSZ (SBEMF
    $BDIF *WZ
    3FQPTJUPSZ /FUXPSL store/access artifacts download artifacts Dependency management in Gradle *.module *.pom ivy.xml module metadata ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle
48. (SBEMF
    #VJME .BWFO
    3FQPTJUPSZ (SBEMF
    $BDIF -PDBM
    'JMF
    3FQPTJUPSZ *WZ
    3FQPTJUPSZ /FUXPSL store/access artifacts download artifacts access artifacts Dependency management in Gradle *.module *.pom ivy.xml module metadata ref: https://docs.gradle.org/5.1.1/userguide/introduction_dependency_management.html#dependency_management_in_gradle
49. BOM \ ͓଴ͨͤ͠·ͨ͠ /
50. BOM? l
    #0.
    #JMMT
    PG
    NBUFSJBMT
    ͱ͸ɺ
 ੡଄ۀͰ༻͍ΒΕΔ෦඼දͷҰܗଶͰ͋Δɻ
 ੡඼Λ૊ΈཱͯΔ࣌ͷ෦඼ͷҰཡͱɺ
 ৔߹ʹΑͬͯ͸֊૚ߏ଄Λද͢ɻz
 
 ref: https://ja.wikipedia.org/wiki/BOM_(෦඼ද)
51. BOM? l
    #0.
    #JMMT
    PG
    NBUFSJBMT
    ͱ͸ɺ
 ੡଄ۀͰ༻͍ΒΕΔ෦඼දͷҰܗଶͰ͋Δɻ
 ੡඼Λ૊ΈཱͯΔ࣌ͷ෦඼ͷҰཡͱɺ
 ৔߹ʹΑͬͯ͸֊૚ߏ଄Λද͢ɻz
 
 ref: https://ja.wikipedia.org/wiki/BOM_(෦඼ද)
52. BOM • MavenͰ࢖ΘΕ͍ͯΔPOM(Project Object Model) ͷ֦ு • ؔ࿈ϥΠϒϥϦͷόʔδϣϯΛ·ͱΊͯఆٛ͢Δ࢓૊Έ • OkHttp : okhttp, okhttp-android-support, okhttp-*** • GCP : google-cloud-core, google-cloud-***, etc... • AWS : aws-java-sdk-core, aws-java-sdk-***, etc... • Gradle͔ΒModule metadataͱͯ͠ࢀরͰ͖Δ
53. e.g. 'com.squareup.okhttp3:okhttp-bom:3.12.1' BOM
54. BOM e.g. 'okhttp-bom-3.12.1.pom' <project ... > <modelVersion>4.0.0</modelVersion> <groupId>com.squareup.okhttp3</groupId> <artifactId>okhttp-bom</artifactId> <version>3.12.1</version> <packaging>pom</packaging> <name>OkHttp (Bill of Materials)</name> <dependencyManagement> <dependencies> <dependency> <groupId>${project.groupId}</groupId> <artifactId>okhttp</artifactId> <version>${project.version}</version> </dependency> <dependency> <groupId>${project.groupId}.groupId}</groupId> <artifactId>okhttp-tests</artifactId> <version>${project.version}</version> </dependency>
55. BOM e.g. 'okhttp-bom-3.12.1.pom' <project ... <dependencyManagement> <dependencies> <dependency> <groupId>${project.groupId}</groupId> <artifactId>okhttp</artifactId> <version>${project.version}</version> </dependency> <dependency> <groupId>${project.groupId}</groupId> <artifactId>okhttp-tests</artifactId> <version>${project.version}</version> </dependency> <dependency> <groupId>${project.groupId}</groupId> <artifactId>okhttp-android-support</artifactId> <version>${project.version}</version> </dependency> <dependency>
56. BOM e.g. 'com.squareup.okhttp3:okhttp-bom:3.12.1' e.g. okhttp-bom:3.12.1 | (Total: 24 dependencies) ├── okhttp:3.12.1 ├── okhttp-tests:3.12.1 ├── okhttp-android-support:3.12.1 ├── okhttp-apache:3.12.1 ├── okhttp-sse:3.12.1 ├── okhttp-testing-support:3.12.1 ├── okhttp-tls:3.12.1 ├── okhttp-urlconnection:3.12.1 ├── okhttp-logging-interceptor:3.12.1 ├── okhttp-dnsoverhttps:3.12.1
57. BOM e.g. 'com.google.cloud:google-cloud-bom:0.79.0-alpha' e.g. google-cloud-bom | (Total: 154 dependencies) ├── google-cloud-core ├── google-cloud-automl ├── google-cloud-datastore ├── google-cloud-dialogflow ├── google-cloud-pubsub ├── google-cloud-storage ├── proto-google-common-protos ├── proto-google-cloud-iot-v1 ├── grpc-google-common-protos ├── grpc-google-cloud-iot-v1
58. BOM e.g. 'com.amazonaws:aws-java-sdk-pom:1.11.490' e.g. aws-java-sdk-pom | (Total: 167 dependencies) ├── aws-java-sdk-core ├── aws-java-sdk-api-gateway ├── aws-java-sdk-s3 ├── aws-java-sdk-iot ├── aws-java-sdk-lambda ├── aws-java-sdk-appsync ├── aws-java-sdk-mobile ├── aws-java-sdk-greengrass ├── aws-java-sdk-dynamodb ├── aws-java-sdk-cognitoidentity
59. BOM • BOMϑΝΠϧࣗମ΋όʔδϣϯΛ࣋ͭɻ
 ϥΠϒϥϦ܈͕৽͘͠ͳͬͨΒόʔδϣϯΛ্ॻ͖ͯ͠ɺ
 ৽͍͠όʔδϣϯͱͯ͠BOMϑΝΠϧΛެ։͢Δɻ • όʔδϣϯ৘ใ͚ͩͳͷͰɺBOMϑΝΠϧΛࢀর͢Δ͜ͱͰ ༨෼ͳϥΠϒϥϦ͕௥Ճ͞ΕΔ͜ͱ͸ͳ͍ɻ
60. BOM • 2019೥2݄࣌఺Ͱ͸ OkHttp, SpringFramework, AWS, GoogleCloud, JUnit౳ͰBOMϑΝΠϧ͕ఏڙ͞Ε͍ͯΔ • Androidؔ࿈ͷϥΠϒϥϦͰ͸΄ͱΜͲఏڙ͞Εͯͳ͍
61. Gradle BOM import \ ΍ͬͱ͜͜·Ͱ͖ͨ /
62. Gradle BOM import
63. Gradle BOM import • Dependency Version Alignment ͱͯ͠BOM importʹରԠ • Gradle5.0͔Βਖ਼ࣜಋೖ • Gradle4.6͔Βࢼݧಋೖ͞Ε͍ͯΔͷͰ࢖༻Մೳ ref: https://docs.gradle.org/5.0/release-notes.html#dependency-version-alignment
 ref: https://docs.gradle.org/4.6/release-notes.html#bom-import
64. Gradle BOM import dependencies { implementation 'com.squareup.okhttp3:okhttp:3.12.0' implementation 'com.squareup.okhttp3:okhttp-tls:3.12.0' implementation 'com.squareup.okhttp3:okhttp-urlconnection:3.12.0' implementation 'com.squareup.okhttp3:logging-interceptor:3.12.0' testImplementation 'com.squareup.okhttp3:mockwebserver:3.12.0' } app/build.gradle
65. Gradle BOM import dependencies {
 // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' )
 implementation 'com.squareup.okhttp3:okhttp:3.12.0' implementation 'com.squareup.okhttp3:okhttp-tls:3.12.0' implementation 'com.squareup.okhttp3:okhttp-urlconnection:3.12.0' implementation 'com.squareup.okhttp3:logging-interceptor:3.12.0' testImplementation 'com.squareup.okhttp3:mockwebserver:3.12.0' } app/build.gradle
66. Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // define dependencies without versions implementation 'com.squareup.okhttp3:okhttp' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } app/build.gradle
67. ͓Θ͔Γ͍͚ͨͩͨͩΖ͏͔ʁ
68. Gradle BOM import dependencies { // ... implementation 'com.squareup.okhttp3:okhttp:3.12.0' implementation 'com.squareup.okhttp3:okhttp-tls:3.12.0' implementation 'com.squareup.okhttp3:okhttp-urlconnection:3.12.0' implementation 'com.squareup.okhttp3:logging-interceptor:3.12.0' testImplementation 'com.squareup.okhttp3:mockwebserver:3.12.0' } app/build.gradle
69. Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // define dependencies without versions implementation 'com.squareup.okhttp3:okhttp' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } app/build.gradle
70. Pros 
 Gradle BOM import • ϥΠϒϥϦؒͰద੾ͳόʔδϣϯΛఆٛͰ͖Δ
 ʢBOMϑΝΠϧ͕໢ཏ͍ͯ͠ΔϥΠϒϥϦ܈ͷதͰʣ • ϥΠϒϥϦ̍ͭ̍ͭʹόʔδϣϯΛॻ͔ͳͯ͘ࡁΉ
 ʢDSLΛ޻෉ͯ͠ఆ਺Λࢀর͠ͳͯ͘Α͘ͳΔʣ
71. Cons 
 Gradle BOM import • ͦ΋ͦ΋͋·Γීٴͯ͠ͳ͍…
72. ext { depends = [ okhttp : [ bom : 'com.squareup.okhttp3:okhttp-bom:3.12.0', okhttp : 'com.squareup.okhttp3:okhttp', tls : 'com.squareup.okhttp3:okhttp-tls', urlconnection : 'com.squareup.okhttp3:okhttp-urlconnection', logginginterceptor : 'com.squareup.okhttp3:logging-interceptor', mockwebserver : 'com.squareup.okhttp3:mockwebserver', ], ... ] } dependencies.gradle Define dependencies in ext Gradle Bom import
73. dependencies { // import a BOM implementation platform(depends.okhttp.bom) // define dependencies without versions implementation depends.okhttp.okhttp implementation depends.okhttp.okhttp-tls implementation depends.okhttp.okhttp-urlconnection implementation depends.okhttp.logging-interceptor testImplementation depends.okhttp.mockwebserver ... } app/build.gradle Define dependencies in ext Gradle Bom import
74. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) implementation('com.squareup.okhttp3:okhttp:3.12.1') { because 'Try new release' } ... }
75. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) implementation('com.squareup.okhttp3:okhttp:3.12.1') { because 'Try new release' } ... } okhttp-bom: 3.12.0 okhttp: 3.12.1
76. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation 'com.squareup.okhttp3:okhttp:3.11.0' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.0 < okhttp: 3.12.1 implementation platform(…) implementation '…'
77. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation 'com.squareup.okhttp3:okhttp:3.11.0' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.1 ? okhttp: 3.12.0 implementation platform(…) implementation '…'
78. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation 'com.squareup.okhttp3:okhttp:3.11.0' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.1 > okhttp: 3.12.0 implementation platform(…) implementation '…'
79. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation('com.squareup.okhttp3:okhttp:3.12.0') { because 'Try new release' } ... } okhttp-bom: 3.12.1 okhttp: 3.12.0 ~
80. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation('com.squareup.okhttp3:okhttp:3.12.0') { force = true } ... } okhttp-bom: 3.12.1 !! okhttp: 3.12.0 !!
81. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation platform( 'com.squareup.okhttp3:okhttp-bom:3.12.1' ) implementation('com.squareup.okhttp3:okhttp:3.12.0') { force = true } ... } 
 okhttp-bom: 3.12.1 < okhttp: 3.12.0 implementation platform(…) implementation('…') { force = true }
82. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation enforcedPlatform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // this version will be overriden by the one found in the BOM implementation 'com.squareup.okhttp3:okhttp:3.12.1' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } platform(…) → enforcedPlatform(…)
83. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation enforcedPlatform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // this version will be overriden by the one found in the BOM implementation 'com.squareup.okhttp3:okhttp:3.12.1' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.0 > okhttp: 3.12.1 implementation enforcedPlatform(…) implementation '…'
84. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation enforcedPlatform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // this version will be overriden by the one found in the BOM implementation 'com.squareup.okhttp3:okhttp:3.12.1' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.1 > okhttp: 3.12.0 implementation enforcedPlatform(…) implementation '…'
85. [Q] Version conflict?
 Gradle BOM import dependencies { // import a BOM implementation enforcedPlatform( 'com.squareup.okhttp3:okhttp-bom:3.12.0' ) // this version will be overriden by the one found in the BOM implementation 'com.squareup.okhttp3:okhttp:3.12.1' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' } 
 okhttp-bom: 3.12.1 < okhttp: 3.12.0 implementation enforcedPlatform(…) implementation('…') { force = true }
86. • Gradle4.6͔Βsettings.gradleʹ௥ه͢Δ͜ͱͰ࢖༻Մೳ ref: https://docs.gradle.org/4.6/release-notes.html#bom-import enableFeaturePreview('IMPROVED_POM_SUPPORT') [nits] For Gradle 4.6
 Gradle BOM import
87. [nits] For Gradle 4.6
 Gradle BOM import dependencies { // import a BOM (Gradle 4.6~) // No `enforced` behavior implementation 'com.squareup.okhttp3:okhttp-bom:3.12.0' // define dependencies without versions implementation 'com.squareup.okhttp3:okhttp' implementation 'com.squareup.okhttp3:okhttp-tls' implementation 'com.squareup.okhttp3:okhttp-urlconnection' implementation 'com.squareup.okhttp3:logging-interceptor' testImplementation 'com.squareup.okhttp3:mockwebserver' }
88. [nits] Dependency constraint (≒ BOM)
 Gradle BOM import dependencies { // define the version of dependencies declared in the build script constraints { implementation('org.apache.httpcomponents:httpclient:4.5.3') { because 'previous versions have a bug impact' } implementation('commons-codec:commons-codec:1.11') } 
 // define dependencies without versions implementation 'org.apache.httpcomponents:httpclient' } ref: https://docs.gradle.org/userguide/managing_transitive_dependencies.html#sec:dependency_constraints
89. Future
90. Future • ϥΠϒϥϦ܈ͷதͰద੾ͳґଘؔ܎Λઃఆ͢ΔͨΊʹɺ
 BOMϑΝΠϧ͕޿·ͬͯ΄͍͠
 ʢJetPack, Firebase, PlayService, etc...ʣ
91. For Library Creator Future ର৅ɿOkHttpͷΑ͏ͳϥΠϒϥϦ܈Λఏڙ͍ͯ͠Δଆ 1. ϥΠϒϥϦͷϦϦʔε࣌ʹBOMϑΝΠϧ(pom.xml)Λ༻ҙ 2. ଞϥΠϒϥϦͱಉ͘͡MavenϦϙδτϦʹΞοϓϩʔυ 3. [IMO] ϥΠϒϥϦͷಋೖઆ໌Ͱ `implementation platform(...)` ref: "Maven Bill Of Materials (BOM) · Issue #4329 · square/okhttp" https://github.com/square/okhttp/issues/4329
92. Q : ࣾ಺ͷશҊ݅Ͱ࢖͍ͬͯΔϥΠϒϥϦͷόʔδϣϯΛ
 BOMͰ؅ཧͰ͖Δʁ A : ͢΂ͯͷϥΠϒϥϦ͸ݱ࣮తͰ͸ͳ͍ɻ
 Ҋ݅ʹΑͬͯϥΠϒϥϦͷߋ৽λΠϛϯά͸·ͪ·ͪɻ
 ݱࡏͷ "ϥΠϒϥϦ܈" Ͱ෼͔ΕΔܗ͕ͪΐ͏ͲΑͦ͞͏ɻ For Team Develop ? Future
93. Gradle BOM import ͰϥΠϒϥϦόʔδϣϯ؅ཧ • BOMϑΝΠϧͰϥΠϒϥϦ܈ͷόʔδϣϯΛἧ͑Δ͜ͱ͕Ͱ͖Δ • ϥΠϒϥϦ܈Λӽ͑ͨґଘؔ܎ʹ͍ͭͯ͸ࠓ·ͰͲ͓Γ • ϥΠϒϥϦ܈ͱҰॹʹBOMϑΝΠϧΛఏڙ͠Α͏ʂ͍ͯͩ͘͠͞ʂ