Search

Chapter 74. Mail

download PDF

Mail Component

The mail component provides access to Email via Spring's Mail support and the underlying JavaMail system.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-mail</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>
Geronimo mail .jar
We have discovered that the geronimo mail .jar (v1.6) has a bug when polling mails with attachments. It cannot correctly identify the Content-Type. So, if you attach a .jpeg file to a mail and you poll it, the Content-Type is resolved as text/plain and not as image/jpeg. For that reason, we have added an org.apache.camel.component.ContentTypeResolver SPI interface which enables you to provide your own implementation and fix this bug by returning the correct Mime type based on the file name. So if the file name ends with jpeg/jpg, you can return image/jpeg.
You can set your custom resolver on the MailComponent instance or on the MailEndpoint instance.
POP3 or IMAP
POP3 has some limitations and end users are encouraged to use IMAP if possible.
Using mock-mail for testing
You can use a mock framework for unit testing, which allows you to test without the need for a real mail server. However you should remember to not include the mock-mail when you go into production or other environments where you need to send mails to a real mail server. Just the presence of the mock-javamail.jar on the classpath means that it will kick in and avoid sending the mails.

URI format

Mail endpoints can have one of the following URI formats (for the protocols, SMTP, POP3, or IMAP, respectively):
smtp://[username@]host[:port][?options]
pop3://[username@]host[:port][?options]
imap://[username@]host[:port][?options]
The mail component also supports secure variants of these protocols (layered over SSL). You can enable the secure protocols by adding s to the scheme:
smtps://[username@]host[:port][?options]
pop3s://[username@]host[:port][?options]
imaps://[username@]host[:port][?options]
You can append query options to the URI in the following format, ?option=value&option=value&...

Sample endpoints

Typically, you specify a URI with login credentials as follows (taking SMTP as an example):
smtp://[username@]host[:port][?password=somepwd]
Alternatively, it is possible to specify both the user name and the password as query options:
smtp://host[:port]?password=somepwd&username=someuser
For example:
smtp://mycompany.mailserver:30?password=tiger&username=scott

Default ports

Default port numbers are supported. If the port number is omitted, Camel determines the port number to use based on the protocol.
Protocol Default Port Number
SMTP 25
SMTPS 465
POP3 110
POP3S 995
IMAP 143
IMAPS 993

Options

Property Default Description
host The host name or IP address to connect to.
port See DefaultPorts The TCP port number to connect on.
username The user name on the email server.
password null The password on the email server.
ignoreUriScheme false If false, Camel uses the scheme to determine the transport protocol (POP, IMAP, SMTP etc.)
defaultEncoding null The default encoding to use for Mime Messages.
contentType text/plain The mail message content type. Use text/html for HTML mails.
folderName INBOX The folder to poll.
destination username@host @deprecated Use the to option instead. The TO recipients (receivers of the email).
to username@host The TO recipients (the receivers of the mail). Separate multiple email addresses with a comma.
replyTo alias@host As of Camel 2.8.4, 2.9.1\+, the Reply-To recipients (the receivers of the response mail). Separate multiple email addresses with a comma.
CC null The CC recipients (the receivers of the mail). Separate multiple email addresses with a comma.
BCC null The BCC recipients (the receivers of the mail). Separate multiple email addresses with a comma.
from camel@localhost The FROM email address.
subject As of Camel 2.3, the Subject of the message being sent. Note: Setting the subject in the header takes precedence over this option.
delete false Deletes the messages after they have been processed. This is done by setting the DELETED flag on the mail message. If false, the SEEN flag is set instead. As of Camel 2.10 you can override this configuration option by setting a header with the key delete to determine if the mail should be deleted or not.
unseen true It is possible to configure a consumer endpoint so that it processes only unseen messages (that is, new messages) or all messages. Note that Camel always skips deleted messages. The default option of true will filter to only unseen messages. POP3 does not support the SEEN flag, so this option is not supported in POP3; use IMAP instead. Important: This option is not in use if you also use searchTerm options. Instead if you want to disable unseen when using searchTerm's then add searchTerm.unseen=false as a term.
copyTo null Camel 2.10: Consumer only. After processing a mail message, it can be copied to a mail folder with the given name. You can override this configuration value, with a header with the key copyTo, allowing you to copy messages to folder names configured at runtime.
fetchSize \-1 Sets the maximum number of messages to consume during a poll. This can be used to avoid overloading a mail server, if a mailbox folder contains a lot of messages. Default value of \-1 means no fetch size and all messages will be consumed. Setting the value to 0 is a special corner case, where Camel will not consume any messages at all.
alternativeBodyHeader CamelMailAlternativeBody Specifies the key to an IN message header that contains an alternative email body. For example, if you send emails in text/html format and want to provide an alternative mail body for non-HTML email clients, set the alternative mail body with this key as a header.
debugMode false Enable debug mode on the underlying mail framework. The SUN Mail framework logs the debug messages to System.out by default.
connectionTimeout 30000 The connection timeout in milliseconds. Default is 30 seconds.
consumer.initialDelay 1000 Milliseconds before the polling starts.
consumer.delay 60000 Camel will poll the mailbox only once a minute by default to avoid overloading the mail server.
consumer.useFixedDelay false Set to true to use a fixed delay between polls, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details.
disconnect false Camel 2.8.3/2.9: Whether the consumer should disconnect after polling. If enabled this forces Camel to connect on each poll.
closeFolder true Camel 2.10.4: Whether the consumer should close the folder after polling. Setting this option to false and having disconnect=false as well, then the consumer keep the folder open between polls.
mail.XXX null Set any additional java mail properties. For instance if you want to set a special property when using POP3 you can now provide the option directly in the URI such as: mail.pop3.forgettopheaders=true. You can set multiple such options, for example: mail.pop3.forgettopheaders=true&mail.mime.encodefilename=true.
mapMailMessage true Camel 2.8: Specifies whether Camel should map the received mail message to Camel body/headers. If set to true, the body of the mail message is mapped to the body of the Camel IN message and the mail headers are mapped to IN headers. If this option is set to false then the IN message contains a raw javax.mail.Message. You can retrieve this raw message by calling exchange.getIn().getBody(javax.mail.Message.class).
maxMessagesPerPoll 0 Specifies the maximum number of messages to gather per poll. By default, no maximum is set. Can be used to set a limit of e.g. 1000 to avoid downloading thousands of files when the server starts up. Set a value of 0 or negative to disable this option.
javaMailSender null Specifies a pluggable org.springframework.mail.javamail.JavaMailSender instance in order to use a custom email implementation. If none provided, Camel uses the default org.springframework.mail.javamail.JavaMailSenderImpl.
ignoreUnsupportedCharset false Option to let Camel ignore unsupported charset in the local JVM when sending mails. If the charset is unsupported then charset=XXX (where XXX represents the unsupported charset) is removed from the content-type and it relies on the platform default instead.
sslContextParameters null Camel 2.10: Reference to a org.apache.camel.util.jsse.SSLContextParameters in the Registry. This reference overrides any configured SSLContextParameters at the component level. See Using the JSSE Configuration Utility.
searchTerm null Camel 2.11: Refers to a javax.mail.search.SearchTerm which allows to filter mails based on search criteria such as subject, body, from, sent after a certain date etc. See further below for examples.
searchTerm.xxx null Camel 2.11: To configure search terms directly from the endpoint uri, which supports a limited number of terms defined by the org.apache.camel.component.mail.SimpleSearchTerm class. See further below for examples.

SSL support

The underlying mail framework is responsible for providing SSL support.  ou may either configure SSL/TLS support by completely specifying the necessary Java Mail API configuration options, or you may provide a configured SSLContextParameters through the component or endpoint configuration.

Using the JSSE Configuration Utility

As of Camel 2.10, the mail component supports SSL/TLS configuration through the Camel JSSE Configuration Utility. This utility greatly decreases the amount of component specific code you need to write and is configurable at the endpoint and component levels. The following examples demonstrate how to use the utility with the mail component.

Programmatic configuration of the endpoint

KeyStoreParameters ksp = new KeyStoreParameters();
ksp.setResource("/users/home/server/truststore.jks");
ksp.setPassword("keystorePassword");
TrustManagersParameters tmp = new TrustManagersParameters();
tmp.setKeyStore(ksp);
SSLContextParameters scp = new SSLContextParameters();
scp.setTrustManagers(tmp);
Registry registry = ...
registry.bind("sslContextParameters", scp);
...
from(...)
  .to("smtps://smtp.google.com?username=user@gmail.com&password=password&sslContextParameters=#sslContextParameters");

Spring DSL based configuration of endpoint

...
<camel:sslContextParameters id="sslContextParameters">
  <camel:trustManagers>
    <camel:keyStore resource="/users/home/server/truststore.jks" password="keystorePassword"/>
  </camel:trustManagers>
</camel:sslContextParameters>...
...
<to uri="smtps://smtp.google.com?username=user@gmail.com&password=password&sslContextParameters=#sslContextParameters"/>...

Configuring JavaMail Directly

Camel uses SUN JavaMail, which only trusts certificates issued by well known Certificate Authorities (the default JVM trust configuration). If you issue your own certificates, you have to import the CA certificates into the JVM's Java trust/key store files, override the default JVM trust/key store files (see SSLNOTES.txt in JavaMail for details).

Mail Message Content

Camel uses the message exchange's IN body as the MimeMessage text content. The body is converted to String.class.
Camel copies all of the exchange's IN headers to the MimeMessage headers.
The subject of the MimeMessage can be configured using a header property on the IN message. The code below demonstrates this:
from("direct:a").setHeader("subject", constant(subject)).to("smtp://james2@localhost");
The same applies for other MimeMessage headers such as recipients, so you can use a header property as To:
Map<String, Object> map = new HashMap<String, Object>();
map.put("To", "davsclaus@apache.org");
map.put("From", "jstrachan@apache.org");
map.put("Subject", "Camel rocks");

String body = "Hello Claus.\nYes it does.\n\nRegards James.";
template.sendBodyAndHeaders("smtp://davsclaus@apache.org", body, map);
Since Camel 2.11 When using the MailProducer the send the mail to server, you should be able to get the message id of the MimeMessage with the key CamelMailMessageId from the Camel message header.

Headers take precedence over pre-configured recipients

The recipients specified in the message headers always take precedence over recipients pre-configured in the endpoint URI. The idea is that if you provide any recipients in the message headers, that is what you get. The recipients pre-configured in the endpoint URI are treated as a fallback.
In the sample code below, the email message is sent to davsclaus@apache.org, because it takes precedence over the pre-configured recipient, info@mycompany.com. Any CC and BCC settings in the endpoint URI are also ignored and those recipients will not receive any mail. The choice between headers and pre-configured settings is all or nothing: the mail component either takes the recipients exclusively from the headers or exclusively from the pre-configured settings. It is not possible to mix and match headers and pre-configured settings.
        Map<String, Object> headers = new HashMap<String, Object>();
        headers.put("to", "davsclaus@apache.org");

        template.sendBodyAndHeaders("smtp://admin@localhost?to=info@mycompany.com", "Hello World", headers);

Multiple recipients for easier configuration

It is possible to set multiple recipients using a comma-separated or a semicolon-separated list. This applies both to header settings and to settings in an endpoint URI. For example:
        Map<String, Object> headers = new HashMap<String, Object>();
        headers.put("to", "davsclaus@apache.org ; jstrachan@apache.org ; ningjiang@apache.org");
The preceding example uses a semicolon, ;, as the separator character.

Setting sender name and email

You can specify recipients in the format, name <email>, to include both the name and the email address of the recipient.
For example, you define the following headers on the a Message:
Map headers = new HashMap();
map.put("To", "Claus Ibsen <davsclaus@apache.org>");
map.put("From", "James Strachan <jstrachan@apache.org>");
map.put("Subject", "Camel is cool");

SUN JavaMail

SUN JavaMail is used under the hood for consuming and producing mails. We encourage end-users to consult these references when using either POP3 or IMAP protocol. Note particularly that POP3 has a much more limited set of features than IMAP.

Samples

We start with a simple route that sends the messages received from a JMS queue as emails. The email account is the admin account on mymailserver.com.
from("jms://queue:subscription").to("smtp://admin@mymailserver.com?password=secret");
In the next sample, we poll a mailbox for new emails once every minute. Notice that we use the special consumer option for setting the poll interval, consumer.delay, as 60000 milliseconds = 60 seconds.
from("imap://admin@mymailserver.com
     password=secret&unseen=true&consumer.delay=60000")
    .to("seda://mails");
In this sample we want to send a mail to multiple recipients:
// all the recipients of this mail are:
// To: camel@riders.org , easy@riders.org
// CC: me@you.org
// BCC: someone@somewhere.org
String recipients = "&To=camel@riders.org,easy@riders.org&CC=me@you.org&BCC=someone@somewhere.org";

from("direct:a").to("smtp://you@mymailserver.com?password=secret&From=you@apache.org" + recipients);

Sending mail with attachment sample

Attachments are not support by all Camel components
The Attachments API is based on the Java Activation Framework and is generally only used by the Mail API. Since many of the other Camel components do not support attachments, the attachments could potentially be lost as they propagate along the route. The rule of thumb, therefore, is to add attachments just before sending a message to the mail endpoint.
The mail component supports attachments. In the sample below, we send a mail message containing a plain text message with a logo file attachment.
// create an exchange with a normal body and attachment to be produced as email
Endpoint endpoint = context.getEndpoint("smtp://james@mymailserver.com?password=secret");

// create the exchange with the mail message that is multipart with a file and a Hello World text/plain message.
Exchange exchange = endpoint.createExchange();
Message in = exchange.getIn();
in.setBody("Hello World");
in.addAttachment("logo.jpeg", new DataHandler(new FileDataSource("src/test/data/logo.jpeg")));

// create a producer that can produce the exchange (= send the mail)
Producer producer = endpoint.createProducer();
// start the producer
producer.start();
// and let it go (processes the exchange by sending the email)
producer.process(exchange);

SSL sample

In this sample, we want to poll our Google mail inbox for mails. To download mail onto a local mail client, Google mail requires you to enable and configure SSL. This is done by logging into your Google mail account and changing your settings to allow IMAP access. Google have extensive documentation on how to do this.
from("imaps://imap.gmail.com?username=YOUR_USERNAME@gmail.com&password=YOUR_PASSWORD"
    + "&delete=false&unseen=true&consumer.delay=60000").to("log:newmail");
The preceding route polls the Google mail inbox for new mails once every minute and logs the received messages to the newmail logger category. Running the sample with DEBUG logging enabled, we can monitor the progress in the logs:
2008-05-08 06:32:09,640 DEBUG MailConsumer - Connecting to MailStore imaps//imap.gmail.com:993 (SSL enabled), folder=INBOX
2008-05-08 06:32:11,203 DEBUG MailConsumer - Polling mailfolder: imaps//imap.gmail.com:993 (SSL enabled), folder=INBOX
2008-05-08 06:32:11,640 DEBUG MailConsumer - Fetching 1 messages. Total 1 messages.
2008-05-08 06:32:12,171 DEBUG MailConsumer - Processing message: messageNumber=[332], from=[James Bond <007@mi5.co.uk>], to=YOUR_USERNAME@gmail.com], subject=[...
2008-05-08 06:32:12,187 INFO  newmail - Exchange[MailMessage: messageNumber=[332], from=[James Bond <007@mi5.co.uk>], to=YOUR_USERNAME@gmail.com], subject=[...

Consuming mails with attachment sample

In this sample we poll a mailbox and store all attachments from the mails as files. First, we define a route to poll the mailbox. As this sample is based on google mail, it uses the same route as shown in the SSL sample:
from("imaps://imap.gmail.com?username=YOUR_USERNAME@gmail.com&password=YOUR_PASSWORD"
    + "&delete=false&unseen=true&consumer.delay=60000").process(new MyMailProcessor());
Instead of logging the mail we use a processor where we can process the mail from java code:
    public void process(Exchange exchange) throws Exception {
        // the API is a bit clunky so we need to loop
        Map<String, DataHandler> attachments = exchange.getIn().getAttachments();
        if (attachments.size() > 0) {
            for (String name : attachments.keySet()) {
                DataHandler dh = attachments.get(name);
                // get the file name
                String filename = dh.getName();

                // get the content and convert it to byte[]
                byte[] data = exchange.getContext().getTypeConverter()
                                  .convertTo(byte[].class, dh.getInputStream());

                // write the data to a file
                FileOutputStream out = new FileOutputStream(filename);
                out.write(data);
                out.flush();
                out.close();
            }
        }
   }
As you can see the API to handle attachments is a bit clunky but it's there so you can get the javax.activation.DataHandler so you can handle the attachments using standard API.

How to split a mail message with attachments

In this example we consume mail messages which may have a number of attachments. What we want to do is to use the Splitter EIP per individual attachment, to process the attachments separately. For example if the mail message has 5 attachments, we want the Splitter to process five messages, each having a single attachment. To do this we need to provide a custom Expression to the Splitter where we provide a List<Message> that contains the five messages with the single attachment.
The code is provided out of the box in Camel 2.10 onwards in the camel-mail component. The code is in the class: org.apache.camel.component.mail.SplitAttachmentsExpression, which you can find the source code here
In the Camel route you then need to use this Expression in the route as shown below:
from("pop3://james@mymailserver.com?password=secret&consumer.delay=1000")
    .to("log:email")
    // use the SplitAttachmentsExpression which will split the message per attachment
    .split(new SplitAttachmentsExpression())
        // each message going to this mock has a single attachment
        .to("mock:split")
    .end();
If you use XML DSL then you need to declare a method call expression in the Splitter as shown below
<split>
  <method beanType="org.apache.camel.component.mail.SplitAttachmentsExpression"/>
  <to uri="mock:split"/>
</split>

Using custom SearchTerm

Available as of Camel 2.11
You can configure a searchTerm on the MailEndpoint which allows you to filter out unwanted mails.
For example to filter mails to contain Camel in either Subject or Text you can do as follows:
<route>
  <from uri="imaps://mymailseerver?username=foo&password=secret&searchTerm.subjectOrBody=Camel"/>
  <to uri="bean:myBean"/>
</route>
Notice we use the "searchTerm.subjectOrBody" as parameter key to indicate that we want to search on mail subject or body, to contain the word "Camel". The class org.apache.camel.component.mail.SimpleSearchTerm has a number of options you can configure:
Or to get the new unseen emails going 24 hours back in time you can do. Notice the "now-24h" syntax. See the table below for more details.
<route>
  <from uri="imaps://mymailseerver?username=foo&password=secret&searchTerm.fromSentDate=now-24h"/>
  <to uri="bean:myBean"/>
</route>
You can have multiple searchTerm in the endpoint uri configuration. They would then be combined together using AND operator, eg so both conditions must match. For example to get the last unseen emails going back 24 hours which has Camel in the mail subject you can do:
<route>
  <from uri="imaps://mymailseerver?username=foo&password=secret&searchTerm.subject=Camel&searchTerm.fromSentDate=now-24h"/>
  <to uri="bean:myBean"/>
</route>
Option Default Description
unseen true Whether to limit by unseen mails only.
subjectOrBody null To limit by subject or body to contain the word.
subject null The subject must contain the word.
body null The body must contain the word.
from null The mail must be from a given email pattern.
to null The mail must be to a given email pattern.
fromSentDate null The mail must be sent after or equals (GE) a given date. The date pattern is yyyy-MM-dd HH:mm:SS, eg use "2012-01-01 00:00:00" to be from the year 2012 onwards. You can use "now" for current timestamp. The "now" syntax supports an optional offset, that can be specified as either + or - with a numeric value. For example for last 24 hours, you can use "now - 24h" or without spaces "now-24h". Notice that Camel supports shorthands for hours, minutes, and seconds.
toSentDate null The mail must be sent before or equals (BE) a given date. The date pattern is yyyy-MM-dd HH:mm:SS, eg use "2012-01-01 00:00:00" to be before the year 2012. You can use "now" for current timestamp. The "now" syntax supports an optional offset, that can be specified as either + or - with a numeric value. For example for last 24 hours, you can use "now - 24h" or without spaces "now-24h". Notice that Camel supports shorthands for hours, minutes, and seconds.
The SimpleSearchTerm is designed to be easily configurable from a POJO, so you can also configure it using a <bean> style in XML
<bean id="mySearchTerm" class="org.apache.camel.component.mail.SimpleSearchTerm">
  <property name="subject" value="Order"/>
  <property name="to" value="acme-order@acme.com"/>
  <property name="fromSentDate" value="now"/>
 </bean>
You can then refer to this bean, using #beanId in your Camel route as shown:
<route>
  <from uri="imaps://mymailseerver?username=foo&password=secret&searchTerm=#mySearchTerm"/>
  <to uri="bean:myBean"/>
</route>
In Java there is a builder class to build compound SearchTerms using the org.apache.camel.component.mail.SearchTermBuilder class. This allows you to build complex terms such as:
// we just want the unseen mails which is not spam
SearchTermBuilder builder = new SearchTermBuilder();

builder.unseen().body(Op.not, "Spam").subject(Op.not, "Spam")
  // which was sent from either foo or bar
  .from("foo@somewhere.com").from(Op.or, "bar@somewhere.com");
  // .. and we could continue building the terms

SearchTerm term = builder.build();
Red Hat logoGithubRedditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

© 2024 Red Hat, Inc.