first commit

.gitignore

@@ -0,0 +1,37 @@
+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/

build.gradle

@@ -0,0 +1,40 @@
+plugins {
+    id 'java'
+    id 'org.springframework.boot' version '3.1.3'
+    id 'io.spring.dependency-management' version '1.1.3'
+}
+
+group = 'com.danielbohry'
+version = '0.0.1'
+
+java {
+    sourceCompatibility = '17'
+}
+
+configurations {
+    compileOnly {
+        extendsFrom annotationProcessor
+    }
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation 'org.springframework.boot:spring-boot-starter-data-mongodb'
+    implementation 'org.springframework.boot:spring-boot-starter-web'
+    implementation 'org.springframework.boot:spring-boot-starter-security'
+    implementation 'io.jsonwebtoken:jjwt:0.9.1'
+    implementation 'com.google.guava:guava:31.1-jre'
+    implementation 'org.springdoc:springdoc-openapi-ui:1.6.11'
+    implementation 'javax.xml.bind:jaxb-api:2.4.0-b180830.0359'
+
+    compileOnly 'org.projectlombok:lombok'
+    annotationProcessor 'org.projectlombok:lombok'
+    testImplementation 'org.springframework.boot:spring-boot-starter-test'
+}
+
+tasks.named('test') {
+    useJUnitPlatform()
+}

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.2.1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -0,0 +1,248 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original 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 POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | 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: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# 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"'
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

gradlew.bat

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+@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=.
+@rem This is normally unused
+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% equ 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% equ 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!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

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+rootProject.name = 'auth-service'

src/main/java/com/danielbohry/authservice/App.java

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

src/main/java/com/danielbohry/authservice/api/AuthController.java

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+package com.danielbohry.authservice.api;
+
+import com.danielbohry.authservice.service.auth.AuthService;
+import lombok.AllArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@Slf4j
+@RestController
+@AllArgsConstructor
+@CrossOrigin
+@RequestMapping("api")
+public class AuthController {
+
+    private final AuthService service;
+
+    @PostMapping("register")
+    public ResponseEntity<AuthenticationResponse> signup(@RequestBody AuthenticationRequest request) {
+        log.info("New signup for username [{}]", request.getUsername());
+        var response = service.signup(request);
+        return ResponseEntity.ok(response);
+    }
+
+    @PostMapping("authenticate")
+    public ResponseEntity<AuthenticationResponse> signin(@RequestBody AuthenticationRequest request) {
+        log.info("New signin for username [{}]", request.getUsername());
+        var response = service.signin(request);
+        return ResponseEntity.ok(response);
+    }
+
+}

src/main/java/com/danielbohry/authservice/api/AuthenticationRequest.java

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+package com.danielbohry.authservice.api;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class AuthenticationRequest {
+
+    private String username;
+    private String password;
+
+}

src/main/java/com/danielbohry/authservice/api/AuthenticationResponse.java

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+package com.danielbohry.authservice.api;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Data
+@Builder
+public class AuthenticationResponse {
+
+    private final String token;
+
+}

src/main/java/com/danielbohry/authservice/common/ControllerAdvisor.java

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+package com.danielbohry.authservice.common;
+
+import com.danielbohry.authservice.exceptions.NotFoundException;
+import io.jsonwebtoken.ExpiredJwtException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.multipart.MultipartException;
+import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
+
+import java.time.LocalDateTime;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+@ControllerAdvice
+public class ControllerAdvisor extends ResponseEntityExceptionHandler {
+
+    @ExceptionHandler(NotFoundException.class)
+    protected ResponseEntity<Object> handleNotFoundException(RuntimeException ex) {
+        Map<String, Object> body = new LinkedHashMap<>();
+        body.put("timestamp", LocalDateTime.now());
+        body.put("message", ex.getMessage());
+
+        return new ResponseEntity<>(body, HttpStatus.NOT_FOUND);
+    }
+
+    @ExceptionHandler(MultipartException.class)
+    protected ResponseEntity<Object> handleMultipartException(RuntimeException ex) {
+        Map<String, Object> body = new LinkedHashMap<>();
+        body.put("timestamp", LocalDateTime.now());
+        body.put("message", ex.getMessage());
+
+        return new ResponseEntity<>(body, HttpStatus.BAD_REQUEST);
+    }
+
+    @ExceptionHandler(ExpiredJwtException.class)
+    protected ResponseEntity<Object> handleExpiredJwtException(RuntimeException ex) {
+        Map<String, Object> body = new LinkedHashMap<>();
+        body.put("timestamp", LocalDateTime.now());
+        body.put("message", ex.getMessage());
+
+        return new ResponseEntity<>(body, HttpStatus.UNAUTHORIZED);
+    }
+
+}

src/main/java/com/danielbohry/authservice/config/SecurityConfig.java

@@ -0,0 +1,58 @@
+package com.danielbohry.authservice.config;
+
+import com.danielbohry.authservice.service.auth.JwtAuthenticationFilter;
+import com.danielbohry.authservice.service.user.UserService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.AuthenticationProvider;
+import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
+import org.springframework.security.config.annotation.authentication.configuration.AuthenticationConfiguration;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+import static org.springframework.security.config.http.SessionCreationPolicy.STATELESS;
+
+@Configuration
+@EnableWebSecurity
+@RequiredArgsConstructor
+public class SecurityConfig {
+
+    private final JwtAuthenticationFilter jwtAuthenticationFilter;
+    private final UserService userService;
+
+    @Bean
+    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
+        http.csrf().disable()
+                .authorizeHttpRequests(request -> request.requestMatchers("/api/**")
+                        .permitAll().anyRequest().authenticated())
+                .sessionManagement(manager -> manager.sessionCreationPolicy(STATELESS))
+                .authenticationProvider(authenticationProvider())
+                .addFilterBefore(jwtAuthenticationFilter, UsernamePasswordAuthenticationFilter.class);
+        return http.build();
+    }
+
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+
+    @Bean
+    public AuthenticationProvider authenticationProvider() {
+        DaoAuthenticationProvider authProvider = new DaoAuthenticationProvider();
+        authProvider.setUserDetailsService(userService.userDetailsService());
+        authProvider.setPasswordEncoder(passwordEncoder());
+        return authProvider;
+    }
+
+    @Bean
+    public AuthenticationManager authenticationManager(AuthenticationConfiguration config) throws Exception {
+        return config.getAuthenticationManager();
+    }
+
+}

src/main/java/com/danielbohry/authservice/domain/ApplicationUser.java

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+package com.danielbohry.authservice.domain;
+
+import lombok.Builder;
+import lombok.Data;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+
+import java.util.Collection;
+import java.util.List;
+
+@Data
+@Builder
+public class ApplicationUser implements UserDetails {
+
+    private String id;
+    private String username;
+    private String password;
+    private String email;
+    private Role role;
+    private boolean active;
+
+    @Override
+    public Collection<? extends GrantedAuthority> getAuthorities() {
+        return List.of(new SimpleGrantedAuthority(role.name()));
+    }
+
+    @Override
+    public boolean isAccountNonExpired() {
+        return this.active;
+    }
+
+    @Override
+    public boolean isAccountNonLocked() {
+        return this.active;
+    }
+
+    @Override
+    public boolean isCredentialsNonExpired() {
+        return this.active;
+    }
+
+    @Override
+    public boolean isEnabled() {
+        return this.active;
+    }
+}

src/main/java/com/danielbohry/authservice/domain/Role.java

@@ -0,0 +1,7 @@
+package com.danielbohry.authservice.domain;
+
+public enum Role {
+
+    ADMIN, USER
+
+}

src/main/java/com/danielbohry/authservice/exceptions/BadRequestException.java

@@ -0,0 +1,12 @@
+package com.danielbohry.authservice.exceptions;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(value = HttpStatus.BAD_REQUEST)
+public class BadRequestException extends RuntimeException {
+
+    public BadRequestException(String message) {
+        super(message);
+    }
+}

src/main/java/com/danielbohry/authservice/exceptions/NotFoundException.java

@@ -0,0 +1,12 @@
+package com.danielbohry.authservice.exceptions;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(value = HttpStatus.NOT_FOUND)
+public class NotFoundException extends RuntimeException {
+
+    public NotFoundException(String message) {
+        super(message);
+    }
+}

src/main/java/com/danielbohry/authservice/repository/UserRepository.java

@@ -0,0 +1,16 @@
+package com.danielbohry.authservice.repository;
+
+import com.danielbohry.authservice.domain.ApplicationUser;
+import org.springframework.data.mongodb.repository.MongoRepository;
+import org.springframework.stereotype.Repository;
+
+import java.util.Optional;
+
+@Repository
+public interface UserRepository extends MongoRepository<ApplicationUser, String> {
+
+    boolean existsByUsername(String username);
+
+    Optional<ApplicationUser> findByUsernameAndActiveTrue(String username);
+
+}

src/main/java/com/danielbohry/authservice/service/auth/AuthService.java

@@ -0,0 +1,53 @@
+package com.danielbohry.authservice.service.auth;
+
+import com.danielbohry.authservice.api.AuthenticationRequest;
+import com.danielbohry.authservice.api.AuthenticationResponse;
+import com.danielbohry.authservice.service.user.UserService;
+import lombok.AllArgsConstructor;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Service;
+
+import static com.danielbohry.authservice.service.auth.UserConverter.convert;
+import static java.util.Collections.singletonList;
+
+@Service
+@AllArgsConstructor
+public class AuthService implements UserDetailsService {
+
+    private final UserService service;
+    private final JwtService jwtService;
+    private final AuthenticationManager authenticationManager;
+    private final PasswordEncoder passwordEncoder;
+
+    @Override
+    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
+        var user = service.findByUsername(username);
+        var authority = new SimpleGrantedAuthority("ROLE_" + user.getRole());
+
+        return new User(user.getUsername(), user.getPassword(), singletonList(authority));
+    }
+
+    public AuthenticationResponse signup(AuthenticationRequest request) {
+        var user = User.builder().username(request.getUsername()).password(passwordEncoder.encode(request.getPassword())).build();
+        service.save(convert(user));
+        var jwt = jwtService.generateToken(user);
+        return AuthenticationResponse.builder().token(jwt).build();
+    }
+
+    public AuthenticationResponse signin(AuthenticationRequest request) {
+        authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(
+                request.getUsername(), request.getPassword())
+        );
+        var user = service.findByUsername(request.getUsername());
+        var jwt = jwtService.generateToken(user);
+        return AuthenticationResponse.builder().token(jwt).build();
+    }
+
+}

src/main/java/com/danielbohry/authservice/service/auth/JwtAuthenticationFilter.java

@@ -0,0 +1,55 @@
+package com.danielbohry.authservice.service.auth;
+
+import com.danielbohry.authservice.service.user.UserService;
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import lombok.RequiredArgsConstructor;
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import java.io.IOException;
+
+@Component
+@RequiredArgsConstructor
+public class JwtAuthenticationFilter extends OncePerRequestFilter {
+
+    private final JwtService jwtService;
+    private final UserService userService;
+
+    @SuppressWarnings("NullableProblems")
+    @Override
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
+        final String authHeader = request.getHeader("Authorization");
+        final String jwt;
+        final String username;
+        if (StringUtils.isEmpty(authHeader) || !StringUtils.startsWith(authHeader, "Bearer ")) {
+            filterChain.doFilter(request, response);
+            return;
+        }
+        jwt = authHeader.substring(7);
+        username = jwtService.extractUsername(jwt);
+        if (StringUtils.isNotEmpty(username)
+                && SecurityContextHolder.getContext().getAuthentication() == null) {
+            UserDetails userDetails = userService.userDetailsService()
+                    .loadUserByUsername(username);
+            if (jwtService.isTokenValid(jwt, userDetails)) {
+                SecurityContext context = SecurityContextHolder.createEmptyContext();
+                UsernamePasswordAuthenticationToken authToken = new UsernamePasswordAuthenticationToken(
+                        userDetails, null, userDetails.getAuthorities()
+                );
+                authToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
+                context.setAuthentication(authToken);
+                SecurityContextHolder.setContext(context);
+            }
+        }
+        filterChain.doFilter(request, response);
+    }
+}

src/main/java/com/danielbohry/authservice/service/auth/JwtService.java

@@ -0,0 +1,66 @@
+package com.danielbohry.authservice.service.auth;
+
+import io.jsonwebtoken.Claims;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.SignatureAlgorithm;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.stereotype.Service;
+
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Function;
+
+import static java.util.stream.Collectors.toSet;
+
+@Service
+public class JwtService {
+
+    @Value("${jwt.secret}")
+    private String secret;
+
+    public String extractUsername(String token) {
+        return extractClaim(token, Claims::getSubject);
+    }
+
+    public Date extractExpiration(String token) {
+        return extractClaim(token, Claims::getExpiration);
+    }
+
+    public <T> T extractClaim(String token, Function<Claims, T> claimsResolver) {
+        final Claims claims = extractAllClaims(token);
+        return claimsResolver.apply(claims);
+    }
+
+    public String generateToken(UserDetails userDetails) {
+        Map<String, Object> claims = new HashMap<>();
+        claims.put(
+                "authorities", userDetails.getAuthorities().stream()
+                        .map(GrantedAuthority::getAuthority)
+                        .collect(toSet())
+        );
+        return generateToken(claims, userDetails);
+    }
+
+    public Boolean isTokenValid(String token, UserDetails userDetails) {
+        final String username = extractUsername(token);
+        return (username.equals(userDetails.getUsername())) && !isTokenExpired(token);
+    }
+
+    private String generateToken(Map<String, Object> claims, UserDetails userDetails) {
+        return Jwts.builder().setClaims(claims).setSubject(userDetails.getUsername()).setIssuedAt(new Date(System.currentTimeMillis()))
+                .setExpiration(new Date(System.currentTimeMillis() + 1000 * 60 * 60 * 48))
+                .signWith(SignatureAlgorithm.HS256, secret).compact();
+    }
+
+    private Claims extractAllClaims(String token) {
+        return Jwts.parser().setSigningKey(secret).parseClaimsJws(token).getBody();
+    }
+
+    private Boolean isTokenExpired(String token) {
+        return extractExpiration(token).before(new Date());
+    }
+
+}

src/main/java/com/danielbohry/authservice/service/auth/UserConverter.java

@@ -0,0 +1,17 @@
+package com.danielbohry.authservice.service.auth;
+
+import com.danielbohry.authservice.domain.ApplicationUser;
+import lombok.experimental.UtilityClass;
+import org.springframework.security.core.userdetails.UserDetails;
+
+@UtilityClass
+public class UserConverter {
+
+    public static ApplicationUser convert(UserDetails user) {
+        return ApplicationUser.builder()
+                .username(user.getUsername())
+                .password(user.getPassword())
+                .build();
+    }
+
+}

src/main/java/com/danielbohry/authservice/service/user/UserService.java

@@ -0,0 +1,55 @@
+package com.danielbohry.authservice.service.user;
+
+import com.danielbohry.authservice.domain.ApplicationUser;
+import com.danielbohry.authservice.exceptions.BadRequestException;
+import com.danielbohry.authservice.exceptions.NotFoundException;
+import com.danielbohry.authservice.repository.UserRepository;
+import lombok.AllArgsConstructor;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.stereotype.Service;
+
+import java.util.UUID;
+
+import static com.danielbohry.authservice.domain.Role.USER;
+
+@Service
+@AllArgsConstructor
+public class UserService {
+
+    private final UserRepository repository;
+
+    public UserDetailsService userDetailsService() {
+        return username -> repository.findByUsernameAndActiveTrue(username)
+                .orElseThrow(() -> new NotFoundException("User not found"));
+    }
+
+    public ApplicationUser findByUsername(String username) {
+        return repository.findByUsernameAndActiveTrue(username)
+                .orElseThrow(() -> new NotFoundException("User not found"));
+    }
+
+    public void save(ApplicationUser applicationUser) {
+        validateUsername(applicationUser);
+
+        applicationUser.setId(UUID.randomUUID().toString());
+        applicationUser.setPassword(applicationUser.getPassword());
+        applicationUser.setRole(USER);
+        applicationUser.setActive(true);
+
+        repository.save(applicationUser);
+    }
+
+    public ApplicationUser update(ApplicationUser applicationUser) {
+        validateUsername(applicationUser);
+        return repository.save(applicationUser);
+    }
+
+    private void validateUsername(ApplicationUser applicationUser) {
+        boolean exists = repository.existsByUsername(applicationUser.getUsername());
+
+        if (exists) {
+            throw new BadRequestException("Username is already in use");
+        }
+    }
+
+}

src/main/resources/application.yml

@@ -0,0 +1,11 @@
+server:
+  port: ${port:8080}
+
+spring:
+  data:
+    mongodb:
+      uri: ${mongo:}
+      database: ${database:auth}
+
+jwt:
+  secret: ${jwt_secret}

src/test/java/com/danielbohry/authservice/AppTests.java

@@ -0,0 +1,13 @@
+package com.danielbohry.authservice;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class AppTests {
+
+    @Test
+    void contextLoads() {
+    }
+
+}