Initial commit [@asegers]

- Spring Boot Api with two employee endpoints
- Dockerfile and docker-compose for building and orchestrating Docker containers and Kubernetes pod

.gitignore

+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

Dockerfile

+
+FROM openjdk:8-jdk-slim as build
+WORKDIR /build
+COPY . .
+RUN ./gradlew build -x test
+FROM openjdk:8-jdk-slim
+EXPOSE 8080
+WORKDIR /app
+COPY --from=build /build/build/libs/docker_k8_employee_service-0.0.1-SNAPSHOT.jar ./employee-service.jar
+ENTRYPOINT [ "java", "-jar", "/app/employee-service.jar" ]

README.md

+# Docker Kubernetes Spring Boot PostgreSQL Demo
+
+## Setup
+Make sure to have Docker installed and open your CLI in the project root.
+
+Build the Docker image for the Spring Boot app by running the following command:
+```bash
+    docker build -t 'asegers/employee-service:1.0' .
+```
+
+Then, build and start the Kubernetes pod by running the following command:
+```bash
+    docker-compose up
+```
+
+You're done! View the all employees endpoint at: [localhost:8080/api/v1/employees/](http://localhost:8080/api/v1/employees/)

build.gradle

+plugins {
+	id 'org.springframework.boot' version '2.4.5'
+	id 'io.spring.dependency-management' version '1.0.11.RELEASE'
+	id 'java'
+}
+
+group = 'com.nisum.asegers'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+configurations {
+	compileOnly {
+		extendsFrom annotationProcessor
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-actuator'
+	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	compileOnly 'org.projectlombok:lombok'
+	runtimeOnly 'org.postgresql:postgresql'
+	annotationProcessor 'org.projectlombok:lombok'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	// https://mvnrepository.com/artifact/com.github.javafaker/javafaker
+	implementation 'com.github.javafaker:javafaker:1.0.2'
+}
+
+test {
+	useJUnitPlatform()
+}

docker-compose.yml

+version: '3.9'
+
+services:
+  springboot_api:
+    image: asegers/employee-service:1.0
+    build: .
+    ports:
+      - "8080:8080"
+    depends_on:
+      - pg_db
+  pg_db:
+    image: postgres:13.2-alpine
+    expose:
+      - "5432"
+    environment:
+      - POSTGRES_DB=employee_service_db
+      - POSTGRES_USER=asegers
+      - POSTGRES_PASSWORD=Password123!

gradle/wrapper/gradle-wrapper.properties

+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.3-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

gradlew.bat

+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

+rootProject.name = 'docker_k8_employee_service'

src/main/java/com/nisum/asegers/docker_k8_employee_service/DockerK8EmployeeServiceApplication.java

+package com.nisum.asegers.docker_k8_employee_service;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class DockerK8EmployeeServiceApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(DockerK8EmployeeServiceApplication.class, args);
+	}
+
+}

src/main/java/com/nisum/asegers/docker_k8_employee_service/controller/EmployeeController.java

+package com.nisum.asegers.docker_k8_employee_service.controller;
+
+import com.nisum.asegers.docker_k8_employee_service.exception.ResourceNotFoundException;
+import com.nisum.asegers.docker_k8_employee_service.model.Employee;
+import com.nisum.asegers.docker_k8_employee_service.service.EmployeeService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@CrossOrigin(origins = "*")
+@RequestMapping("/api/v1/employees")
+public class EmployeeController {
+    @Autowired
+    EmployeeService employeeService;
+
+    @GetMapping("/")
+    public ResponseEntity<List<Employee>> getAllEmployees() {
+        return ResponseEntity.ok().body(employeeService.getAllEmployees());
+    }
+
+    @GetMapping("/{id}")
+    public ResponseEntity<Employee> getAllEmployees(@PathVariable(value= "id") Long id) throws ResourceNotFoundException {
+        Employee employee =  employeeService.getEmployeeById(id)
+                .orElseThrow(() ->  new ResourceNotFoundException("Employee with id: " + id + " does not exit"));
+        return ResponseEntity.ok().body(employee);
+    }
+}

src/main/java/com/nisum/asegers/docker_k8_employee_service/exception/ResourceNotFoundException.java

+package com.nisum.asegers.docker_k8_employee_service.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(value = HttpStatus.NOT_FOUND)
+public class ResourceNotFoundException extends Exception {
+    public ResourceNotFoundException(String message) { super(message); }
+}

src/main/java/com/nisum/asegers/docker_k8_employee_service/model/Employee.java

+package com.nisum.asegers.docker_k8_employee_service.model;
+
+import lombok.Data;
+
+import javax.persistence.*;
+
+@Entity
+@Table(name= "employees")
+@Data
+public class Employee {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    Long id;
+
+    String firstName, lastName;
+}

src/main/java/com/nisum/asegers/docker_k8_employee_service/repository/EmployeeRepository.java

+package com.nisum.asegers.docker_k8_employee_service.repository;
+
+import com.nisum.asegers.docker_k8_employee_service.model.Employee;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface EmployeeRepository extends JpaRepository<Employee, Long> { }

src/main/java/com/nisum/asegers/docker_k8_employee_service/repository/seeder/Seeder.java

+package com.nisum.asegers.docker_k8_employee_service.repository.seeder;
+
+import com.github.javafaker.Faker;
+import com.nisum.asegers.docker_k8_employee_service.model.Employee;
+import com.nisum.asegers.docker_k8_employee_service.repository.EmployeeRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class Seeder {
+    @Autowired
+    EmployeeRepository employeeRepository;
+
+    @EventListener
+    public void seed(ContextRefreshedEvent event) {
+        seedEmployees(10);
+    }
+
+    private Employee generateEmployee() {
+        Faker faker  = new Faker();
+        Employee employee = new Employee();
+        employee.setFirstName(faker.name().firstName());
+        employee.setLastName(faker.name().lastName());
+        return employee;
+    }
+
+    public void seedEmployees(int count) {
+        for (int n = 0; n < count; n++)
+            employeeRepository.save(generateEmployee());
+    }
+}

src/main/java/com/nisum/asegers/docker_k8_employee_service/service/EmployeeService.java

+package com.nisum.asegers.docker_k8_employee_service.service;
+
+import com.nisum.asegers.docker_k8_employee_service.model.Employee;
+import com.nisum.asegers.docker_k8_employee_service.repository.EmployeeRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+import java.util.Optional;
+
+@Service
+public class EmployeeService {
+    @Autowired
+    EmployeeRepository employeeRepository;
+
+    public List<Employee> getAllEmployees() {
+        return employeeRepository.findAll();
+    }
+
+    public Optional<Employee> getEmployeeById(Long Id) {
+        return employeeRepository.findById(Id);
+    }
+}

src/main/resources/application.properties

+spring.datasource.initialization-mode=always
+spring.datasource.continue-on-error=true
+
+spring.datasource.url=jdbc:postgresql://pg_db:5432/employee_service_db
+spring.datasource.username=asegers
+spring.datasource.password=Password123!
+
+spring.jpa.databasePlatform=org.hibernate.dialect.PostgreSQL82Dialect
+spring.jpa.properties.hibernate.show_sql=true
+spring.jpa.hibernate.ddl-auto=create-drop
+

src/test/java/com/nisum/asegers/docker_k8_employee_service/DockerK8EmployeeServiceApplicationTests.java

+package com.nisum.asegers.docker_k8_employee_service;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class DockerK8EmployeeServiceApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}