[SRD] Demo project for Spring Reactive Programming

Demo project for Spring Reactive Programming

README.md

 # spring-reactive-demo
 
+Requirements
+Java - 1.8.x
+
+Maven - 3.x.x
+
+MongoDB - 3.x.x
+
+Steps to Setup
+1. Clone the application
+``
+git clone https://gitlab.mynisum.com/vrajesh/spring-reactive-demo.git
+``
+
+2. Build and run the app using maven
+
+``
+cd spring-reactive-demo
+mvn package
+java -jar target/spring-reactive-demo-1.0-SNAPSHOT.jar
+``
+
+Alternatively, you can run the app without packaging it using -
+
+``
+mvn spring-boot:run
+``
+
+``
+The server will start at http://localhost:8080.
+``
+
+Exploring the Rest APIs
+The application defines following REST APIs
+
+``
+1. GET /myTweets - Get All Tweets
+2. POST /createTweet - Create a new Tweet
+3. GET /myTweets/{tweetId} - Retrieve a Tweet by Id
+4. PUT /myTweets/{tweetId} - Update a Tweet
+5. DELETE /myTweets/{tweetId} - Delete a Tweet
+6. GET /stream/tweets - Stream tweets to a browser as Server-Sent Events
+``
+
+Running integration tests
+
+``
+The project also contains integration tests for all the Rest APIs. For running the integration tests, go to the root directory of the project and type mvn test in your terminal.
+``
\ No newline at end of file

mvnw

+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  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"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  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
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

mvnw.cmd

+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  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,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.2.4.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	
+	<groupId>com.spring.reactive</groupId>
+	<artifactId>spring-reactive-demo</artifactId>
+	<version>1.0-SNAPSHOT</version>
+	<name>spring-reactive-demo</name>
+	<description>Demo project for Spring Webflux with MongoDB</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-webflux</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>io.projectreactor</groupId>
+			<artifactId>reactor-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+            <groupId>de.flapdoodle.embed</groupId>
+            <artifactId>de.flapdoodle.embed.mongo</artifactId>
+            <scope>test</scope>
+        </dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

src/main/java/com/spring/webflux/demo/SpringReactiveDemoApplication.java

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

src/main/java/com/spring/webflux/demo/controller/TweetController.java

+/**
+ * 
+ */
+package com.spring.webflux.demo.controller;
+
+import javax.validation.Valid;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.dao.DuplicateKeyException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.spring.webflux.demo.exception.TweetNotFoundException;
+import com.spring.webflux.demo.model.Tweet;
+import com.spring.webflux.demo.payload.ErrorResponse;
+import com.spring.webflux.demo.repository.TweetRepository;
+
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+/**
+ * @author vrajesh
+ *
+ */
+@RestController
+public class TweetController {
+
+	@Autowired
+	private TweetRepository tweetRepository;
+
+	/**
+	 * Method to return all the tweets
+	 * 
+	 * @return
+	 */
+	@GetMapping("/myTweets")
+	public Flux<Tweet> getAllMyTweets() {
+		return tweetRepository.findAll();
+	}
+
+	/**
+	 * Method to create a new Tweet
+	 * 
+	 * @param myTweet
+	 * @return
+	 */
+	@PostMapping("/createTweet")
+	public Mono<Tweet> createTweet(@Valid @RequestBody Tweet myTweet) {
+		return tweetRepository.save(myTweet);
+	}
+
+	/**
+	 * Method to retrieve tweet by tweetId
+	 * 
+	 * @param tweetId
+	 * @return
+	 */
+	@GetMapping("/myTweets/{tweetId}")
+	public Mono<ResponseEntity<Tweet>> getTweetById(@PathVariable(value = "tweetId") String tweetId) {
+		return tweetRepository.findById(tweetId).map(savedTweet -> ResponseEntity.ok(savedTweet))
+				.defaultIfEmpty(ResponseEntity.notFound().build());
+	}
+
+	/**
+	 * Method to update Tweet by tweetId
+	 * 
+	 * @param tweetId
+	 * @param tweet
+	 * @return
+	 */
+	@PutMapping("/myTweets/{tweetId}")
+	public Mono<ResponseEntity<Tweet>> updateTweet(@PathVariable(value = "tweetId") String tweetId,
+			@Valid @RequestBody Tweet tweet) {
+		return tweetRepository.findById(tweetId).flatMap(existingTweet -> {
+			existingTweet.setText(tweet.getText());
+			return tweetRepository.save(existingTweet);
+		}).map(updateTweet -> new ResponseEntity<>(updateTweet, HttpStatus.OK))
+				.defaultIfEmpty(new ResponseEntity<>(HttpStatus.NOT_FOUND));
+	}
+
+	/**
+	 * Method to delete Tweet by tweetId
+	 * 
+	 * @param tweetId
+	 * @return
+	 */
+	@DeleteMapping("/myTweets/{tweetId}")
+	public Mono<ResponseEntity<Void>> deleteTweet(@PathVariable(value = "tweetId") String tweetId) {
+
+		return tweetRepository.findById(tweetId)
+				.flatMap(existingTweet -> tweetRepository.delete(existingTweet)
+						.then(Mono.just(new ResponseEntity<Void>(HttpStatus.OK))))
+				.defaultIfEmpty(new ResponseEntity<>(HttpStatus.NOT_FOUND));
+	}
+
+	/**
+	 * Tweets are Sent to the client as Server Sent Events
+	 * 
+	 * @return
+	 */
+	@GetMapping(value = "/stream/tweets", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
+	public Flux<Tweet> streamAllTweets() {
+		return tweetRepository.findAll();
+	}
+
+	/**
+	 * Exception Handling Examples (These can be put into a @ControllerAdvice to
+	 * handle exceptions globally)
+	 * 
+	 * @param ex
+	 * @return
+	 */
+
+	@SuppressWarnings("rawtypes")
+	@ExceptionHandler(DuplicateKeyException.class)
+	public ResponseEntity handleDuplicateKeyException(DuplicateKeyException ex) {
+		return ResponseEntity.status(HttpStatus.CONFLICT)
+				.body(new ErrorResponse("A Tweet with the same text already exists"));
+	}
+
+	/**
+	 * Method to handle tweet not found exception
+	 * 
+	 * @param ex
+	 * @return
+	 */
+	@SuppressWarnings("rawtypes")
+	@ExceptionHandler(TweetNotFoundException.class)
+	public ResponseEntity handleTweetNotFoundException(TweetNotFoundException ex) {
+		return ResponseEntity.notFound().build();
+	}
+}

src/main/java/com/spring/webflux/demo/exception/TweetNotFoundException.java

+/**
+ * 
+ */
+package com.spring.webflux.demo.exception;
+
+/**
+ * @author vrajesh
+ *
+ */
+public class TweetNotFoundException extends RuntimeException {
+
+	/**
+	 * 
+	 */
+	private static final long serialVersionUID = 3812753207617942991L;
+
+	public TweetNotFoundException(String tweetId) {
+		super("Tweet not found with id " + tweetId);
+	}
+}

src/main/java/com/spring/webflux/demo/model/Tweet.java

+/**
+ * 
+ */
+package com.spring.webflux.demo.model;
+
+import java.util.Date;
+
+import javax.validation.constraints.NotBlank;
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Size;
+
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+/**
+ * @author vrajesh
+ *
+ */
+@Document(collection = "mytweets")
+public class Tweet {
+
+	@Id
+	private String id;
+
+	@NotBlank
+	@Size(max = 140)
+	private String text;
+
+	@NotNull
+	private Date createdAt = new Date();
+
+	public Tweet() {
+
+	}
+
+	public Tweet(String text) {
+		this.id = id;
+		this.text = text;
+	}
+
+	/**
+	 * @return the id
+	 */
+	public String getId() {
+		return id;
+	}
+
+	/**
+	 * @param id the id to set
+	 */
+	public void setId(String id) {
+		this.id = id;
+	}
+
+	/**
+	 * @return the text
+	 */
+	public String getText() {
+		return text;
+	}
+
+	/**
+	 * @param text the text to set
+	 */
+	public void setText(String text) {
+		this.text = text;
+	}
+
+	/**
+	 * @return the createdAt
+	 */
+	public Date getCreatedAt() {
+		return createdAt;
+	}
+
+	/**
+	 * @param createdAt the createdAt to set
+	 */
+	public void setCreatedAt(Date createdAt) {
+		this.createdAt = createdAt;
+	}
+
+}

src/main/java/com/spring/webflux/demo/payload/ErrorResponse.java

+/**
+ * 
+ */
+package com.spring.webflux.demo.payload;
+
+/**
+ * @author vrajesh
+ *
+ */
+public class ErrorResponse {
+	private String errorMessage;
+
+	/**
+	 * @param errorMessage
+	 */
+	public ErrorResponse(String errorMessage) {
+		this.errorMessage = errorMessage;
+	}
+
+	/**
+	 * @return the errorMessage
+	 */
+	public String getErrorMessage() {
+		return errorMessage;
+	}
+
+	/**
+	 * @param errorMessage the errorMessage to set
+	 */
+	public void setErrorMessage(String errorMessage) {
+		this.errorMessage = errorMessage;
+	}
+
+}

src/main/java/com/spring/webflux/demo/repository/TweetRepository.java

+/**
+ * 
+ */
+package com.spring.webflux.demo.repository;
+
+import org.springframework.data.mongodb.repository.ReactiveMongoRepository;
+import org.springframework.stereotype.Repository;
+
+import com.spring.webflux.demo.model.Tweet;
+
+/**
+ * @author vrajesh
+ *
+ */
+@Repository
+public interface TweetRepository extends ReactiveMongoRepository<Tweet, String> {
+
+}

src/main/resources/application.properties

+spring.data.mongodb.uri=mongodb://localhost:27017/spring_reactive_demo
\ No newline at end of file

src/test/java/com/spring/webflux/demo/SpringReactiveDemoApplicationTests.java

+package com.spring.webflux.demo;
+
+import java.util.Collections;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+import com.spring.webflux.demo.model.Tweet;
+import com.spring.webflux.demo.repository.TweetRepository;
+
+import reactor.core.publisher.Mono;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+class SpringReactiveDemoApplicationTests {
+
+	@Autowired
+	private WebTestClient webTestClient;
+
+	@Autowired
+	TweetRepository tweetRepository;
+
+	@Test
+	public void testCreateTweet() {
+		Tweet tweet = new Tweet("This is a Test Tweet");
+
+		webTestClient.post().uri("/createTweet").contentType(MediaType.APPLICATION_JSON)
+				.accept(MediaType.APPLICATION_JSON).body(Mono.just(tweet), Tweet.class).exchange().expectStatus()
+				.isOk().expectHeader().contentType(MediaType.APPLICATION_JSON).expectBody().jsonPath("$.id")
+				.isNotEmpty().jsonPath("$.text").isEqualTo("This is a Test Tweet");
+	}
+
+	@Test
+	public void testGetAllTweets() {
+		webTestClient.get().uri("/myTweets").accept(MediaType.APPLICATION_JSON).exchange().expectStatus().isOk()
+				.expectHeader().contentType(MediaType.APPLICATION_JSON).expectBodyList(Tweet.class);
+	}
+
+	@Test
+	public void testGetSingleTweet() {
+		Tweet tweet = tweetRepository.save(new Tweet("Hello, World!")).block();
+
+		webTestClient.get().uri("/myTweets/{id}", Collections.singletonMap("id", tweet.getId())).exchange()
+				.expectStatus().isOk().expectBody()
+				.consumeWith(response -> Assertions.assertThat(response.getResponseBody()).isNotNull());
+	}
+
+	@Test
+	public void testUpdateTweet() {
+		Tweet tweet = tweetRepository.save(new Tweet("Initial Tweet")).block();
+
+		Tweet newTweetData = new Tweet("Updated Tweet");
+
+		webTestClient.put().uri("/myTweets/{id}", Collections.singletonMap("id", tweet.getId()))
+				.contentType(MediaType.APPLICATION_JSON).accept(MediaType.APPLICATION_JSON)
+				.body(Mono.just(newTweetData), Tweet.class).exchange().expectStatus().isOk().expectHeader()
+				.contentType(MediaType.APPLICATION_JSON).expectBody().jsonPath("$.text")
+				.isEqualTo("Updated Tweet");
+	}
+
+	@Test
+	public void testDeleteTweet() {
+		Tweet tweet = tweetRepository.save(new Tweet("To be deleted")).block();
+
+		webTestClient.delete().uri("/myTweets/{id}", Collections.singletonMap("id", tweet.getId())).exchange()
+				.expectStatus().isOk();
+	}
+
+}