[kotlin-client] add spotless plugin (#16645)

* add spotless plugin to kotlin client

* add spotless plugin to kotlin client

* use 6.13.0

modules/openapi-generator/src/main/resources/kotlin-client/build.gradle.mustache

@@ -37,6 +37,7 @@ buildscript {
     {{/useSpringBoot3}}
     ext.reactor_version = "3.5.6"
     {{/jvm-spring-webclient}}
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
@@ -46,6 +47,7 @@ buildscript {
         {{#kotlinx_serialization}}
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
         {{/kotlinx_serialization}}
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
@@ -63,6 +65,7 @@ apply plugin: 'kotlinx-serialization'
 apply plugin: 'idea'
 {{/idea}}
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 {{^useSettingsGradle}}
 
 repositories {
@@ -70,6 +73,27 @@ repositories {
 }
 {{/useSettingsGradle}}
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/others/kotlin-jvm-okhttp-parameter-tests/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-allOff-discriminator/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-array-simple-string-jvm-okhttp3/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-array-simple-string-jvm-okhttp4/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-bigdecimal-default-okhttp4/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-default-values-jvm-okhttp3/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-default-values-jvm-okhttp4/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-default-values-jvm-retrofit2/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.retrofitVersion = '2.9.0'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-enum-default-value/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-gson/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jackson/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-json-request-string/build.gradle

@@ -8,6 +8,7 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
@@ -15,6 +16,7 @@ buildscript {
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
@@ -22,11 +24,33 @@ apply plugin: 'kotlin'
 apply plugin: 'kotlin-parcelize'
 apply plugin: 'kotlinx-serialization'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-jackson/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.retrofitVersion = '2.9.0'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-ktor-gson/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.ktor_version = '2.1.3'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-ktor-jackson/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.ktor_version = '2.1.3'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-ktor-kotlinx_serialization/build.gradle

@@ -9,6 +9,7 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.ktor_version = '2.1.3'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
@@ -16,17 +17,40 @@ buildscript {
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'kotlinx-serialization'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-okhttp4-coroutines/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-spring-2-webclient/build.gradle

@@ -10,22 +10,46 @@ buildscript {
     ext.kotlin_version = '1.8.10'
     ext.spring_boot_version = "2.7.12"
     ext.reactor_version = "3.5.6"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-spring-3-webclient/build.gradle

@@ -10,22 +10,46 @@ buildscript {
     ext.kotlin_version = '1.8.10'
     ext.spring_boot_version = "3.1.0"
     ext.reactor_version = "3.5.6"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-vertx-gson/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.vertx_version = "4.3.3"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-vertx-jackson-coroutines/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.vertx_version = "4.3.3"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-vertx-jackson/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.vertx_version = "4.3.3"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-jvm-vertx-moshi/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.vertx_version = "4.3.3"
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-modelMutable/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-moshi-codegen/build.gradle

@@ -8,23 +8,47 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'kotlin-kapt'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-name-parameter-mappings/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-nonpublic/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-nullable/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-okhttp3/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-retrofit2-kotlinx_serialization/build.gradle

@@ -9,6 +9,7 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.retrofitVersion = '2.9.0'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
@@ -16,17 +17,40 @@ buildscript {
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'kotlinx-serialization'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-retrofit2-rx3/build.gradle

@@ -10,22 +10,46 @@ buildscript {
     ext.kotlin_version = '1.8.10'
     ext.retrofitVersion = '2.9.0'
     ext.rxJava3Version = '3.0.12'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-retrofit2/build.gradle

@@ -9,22 +9,46 @@ wrapper {
 buildscript {
     ext.kotlin_version = '1.8.10'
     ext.retrofitVersion = '2.9.0'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-string/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-threetenbp/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin-uppercase-enum/build.gradle

@@ -8,6 +8,7 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
@@ -15,17 +16,40 @@ buildscript {
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'kotlinx-serialization'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }

samples/client/petstore/kotlin/build.gradle

@@ -8,22 +8,46 @@ wrapper {
 
 buildscript {
     ext.kotlin_version = '1.8.10'
+    ext.spotless_version = "6.13.0"
 
     repositories {
         maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
     }
 }
 
 apply plugin: 'kotlin'
 apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
 
 repositories {
     maven { url "https://repo1.maven.org/maven2" }
 }
 
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
 test {
     useJUnitPlatform()
 }