Mailbox Reader Exchange

This time I will show you how to read an Outlook Exchange mailbox using Exchange Web Services Java API ews-java-api. First you need to define your build.gradle as follow:

def configurationDirectory = "${System.getProperty('user.home')}/.mailboxi-reader"

buildscript {
  ext {
    springBootVersion = '1.5.1.RELEASE'
    cglibVersion = '3.2.4'
    javaMailVersion = '1.4'
    ewsJavaApiVersion = '2.0'
  }
  repositories {
    mavenCentral()
  }
  dependencies {
    classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
  }
}

apply plugin: "groovy"
apply plugin: "application"
apply plugin: 'org.springframework.boot'

jar {
  baseName = 'mailbox-reader'
  version = '0.0.1-SNAPSHOT'
}

sourceCompatibility = 1.8

repositories {
  mavenCentral()
}

dependencies {
  compile 'org.springframework.boot:spring-boot-starter'
  compile 'org.codehaus.groovy:groovy'
  compile "javax.mail:mail:$javaMailVersion"
  compile "com.microsoft.ews-java-api:ews-java-api:$ewsJavaApiVersion"
  testCompile 'org.springframework.boot:spring-boot-starter-test'
  testCompile 'org.spockframework:spock-spring'
  testCompile "cglib:cglib-nodep:$cglibVersion"
}

task settingEnvironment(type:Copy) {
  from configurationDirectory
  into 'src/main/resources'
  include "application.properties"
}

processResources.dependsOn "settingEnvironment"

This is the Exchange mailbox reader implementation

package com.jos.dem.mailbox.reader.service.impl

import org.springframework.stereotype.Service
import org.springframework.beans.factory.annotation.Value
import org.springframework.beans.factory.annotation.Autowired

import microsoft.exchange.webservices.data.core.ExchangeService
import microsoft.exchange.webservices.data.core.PropertySet
import microsoft.exchange.webservices.data.core.service.item.Item
import microsoft.exchange.webservices.data.core.service.folder.Folder
import microsoft.exchange.webservices.data.core.service.item.EmailMessage
import microsoft.exchange.webservices.data.credential.WebCredentials
import microsoft.exchange.webservices.data.credential.ExchangeCredentials
import microsoft.exchange.webservices.data.misc.ImpersonatedUserId
import microsoft.exchange.webservices.data.search.ItemView
import microsoft.exchange.webservices.data.search.FindItemsResults
import microsoft.exchange.webservices.data.property.complex.Mailbox
import microsoft.exchange.webservices.data.property.complex.FolderId
import microsoft.exchange.webservices.data.core.enumeration.misc.ConnectingIdType
import microsoft.exchange.webservices.data.autodiscover.IAutodiscoverRedirectionUrl
import microsoft.exchange.webservices.data.core.enumeration.property.WellKnownFolderName

import javax.annotation.PostConstruct

import com.jos.dem.mailbox.reader.service.InboxReader

import org.slf4j.Logger
import org.slf4j.LoggerFactory

@Service
class InboxReaderExchange implements InboxReader {

  private static final Integer MAX_ITEMS=50

  @Value('${ews.username}')
  String username
  @Value('${ews.password}')
  String password
  @Value('${ews.server}')
  String server
  @Value('${ews.protocol}')
  String protocol

  ExchangeService service = new ExchangeService()

  Logger log = LoggerFactory.getLogger(this.class)

  @PostConstruct
  void setup(){
    service.setUrl(new URI(server))
    ExchangeCredentials credentials = new WebCredentials(username, password)
    service.setCredentials(credentials)
    service.autodiscoverUrl(username,  new RedirectionUrlCallback(protocol))
  }

  void read(){
    Folder folder = Folder.bind(service, WellKnownFolderName.Inbox)
    FindItemsResults<Item> results = service.findItems(folder.getId(), new ItemView(MAX_ITEMS))
    for (Item item : results) {
      EmailMessage emailMessage = EmailMessage.bind(service, item.getId())
      log.info("Sender: ${emailMessage.getSender()}")
      log.info("Subject: ${emailMessage.getSubject()}")
    }
  }

}

class RedirectionUrlCallback implements IAutodiscoverRedirectionUrl {

  String protocol

  RedirectionUrlCallback(String protocol){
    this.protocol = protocol
  }
  public boolean autodiscoverRedirectionUrlValidationCallback(
    String redirectionUrl) {
    return redirectionUrl.toLowerCase().startsWith(protocol)
  }

}

Output

Started MailboxReaderApplication in 9.162 seconds (JVM running for 10.01)
Reading message
Sender: TheDailyInc <noreply@outlook.com>
Subject: Team at Cannes, VIA progress report, Brand Central, and Houston groundbreaking
Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@763d9750

If the domain that the user inputs as their email address contains a CNAME that redirects the user this Exception is thrown:

microsoft.exchange.webservices.data.autodiscover.exception.AutodiscoverLocalException: Autodiscover blocked a potentially insecure redirection to URL. To allow Autodiscover to follow the redirection, use the AutodiscoverUrl(string, AutodiscoverRedirectionUrlValidationCallback) overload.

When this happens, instead of failing, the user can be prompted to accept the redirection or not. That functionality needs to be implemented inside the autodiscoverRedirectionUrlValidationCallback method.

Configuration

In your computer’s home directory: ${home}, create a directory called: .mailbox-reader then inside create a file called application.properties with this content

username=user@gmail.com
password=secret
pop3.server=pop.gmail.com
pop3.port=995
imap.server=imap.gmail.com
imap.port=993
ews.username=user@outlook.com
ews.password=secret
ews.server=https://exchange/EWS/Exchange.asmx
ews.protocol=https://

Build

gradle build

Run

 java -jar build/libs/mailbox-reader-0.0.1-SNAPSHOT.jar

To download the code:

git clone https://github.com/josdem/java-topics.git
cd mailbox-reader

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