Chapter 38. Mail
Both producer and consumer are supported
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>{CamelSBVersion}</version> <!-- use the same version as your Camel core version --> </dependency>
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.
38.1. 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]
38.2. Configuring Options
Camel components are configured on two separate levels:
- component level
- endpoint level
38.2.1. Configuring Component Options
The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example a component may have security settings, credentials for authentication, urls for network connection and so forth.
Some components only have a few options, and others may have many. Because components typically have pre configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.
Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.
38.2.2. Configuring Endpoint Options
Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.
Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL as a type safe way of configuring endpoints.
A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.
The following two sections lists all the options, firstly for the component followed by the endpoint.
38.3. Component Options
The Mail component supports 43 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
bridgeErrorHandler (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean |
closeFolder (consumer) | 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. | true | boolean |
copyTo (consumer) | 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. | String | |
decodeFilename (consumer) | If set to true, the MimeUtility.decodeText method will be used to decode the filename. This is similar to setting JVM system property mail.mime.encodefilename. | false | boolean |
delete (consumer) | 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. | false | boolean |
disconnect (consumer) | Whether the consumer should disconnect after polling. If enabled this forces Camel to connect on each poll. | false | boolean |
handleFailedMessage (consumer) | If the mail consumer cannot retrieve a given mail message, then this option allows to handle the caused exception by the consumer’s error handler. By enable the bridge error handler on the consumer, then the Camel routing error handler can handle the exception instead. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | boolean |
mimeDecodeHeaders (consumer) | This option enables transparent MIME decoding and unfolding for mail headers. | false | boolean |
moveTo (consumer) | After processing a mail message, it can be moved to a mail folder with the given name. You can override this configuration value, with a header with the key moveTo, allowing you to move messages to folder names configured at runtime. | String | |
peek (consumer) | Will mark the javax.mail.Message as peeked before processing the mail message. This applies to IMAPMessage messages types only. By using peek the mail will not be eager marked as SEEN on the mail server, which allows us to rollback the mail message if there is an error processing in Camel. | true | boolean |
skipFailedMessage (consumer) | If the mail consumer cannot retrieve a given mail message, then this option allows to skip the message and move on to retrieve the next mail message. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | boolean |
unseen (consumer) | Whether to limit by unseen mails only. | true | boolean |
fetchSize (consumer (advanced)) | 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. | -1 | int |
folderName (consumer (advanced)) | The folder to poll. | INBOX | String |
mapMailMessage (consumer (advanced)) | Specifies whether Camel should map the received mail message to Camel body/headers/attachments. If set to true, the body of the mail message is mapped to the body of the Camel IN message, the mail headers are mapped to IN headers, and the attachments to Camel IN attachment message. 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). | true | boolean |
bcc (producer) | Sets the BCC email address. Separate multiple email addresses with comma. | String | |
cc (producer) | Sets the CC email address. Separate multiple email addresses with comma. | String | |
from (producer) | The from email address. | camel@localhost | String |
lazyStartProducer (producer) | Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | false | boolean |
replyTo (producer) | The Reply-To recipients (the receivers of the response mail). Separate multiple email addresses with a comma. | String | |
subject (producer) | The Subject of the message being sent. Note: Setting the subject in the header takes precedence over this option. | String | |
to (producer) | Sets the To email address. Separate multiple email addresses with comma. | String | |
javaMailSender (producer (advanced)) | To use a custom org.apache.camel.component.mail.JavaMailSender for sending emails. | JavaMailSender | |
additionalJavaMailProperties (advanced) | Sets additional java mail properties, that will append/override any default properties that is set based on all the other options. This is useful if you need to add some special options but want to keep the others as is. | Properties | |
alternativeBodyHeader (advanced) | 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. | CamelMailAlternativeBody | String |
attachmentsContentTransferEncodingResolver (advanced) | To use a custom AttachmentsContentTransferEncodingResolver to resolve what content-type-encoding to use for attachments. | AttachmentsContentTransferEncodingResolver | |
authenticator (advanced) | The authenticator for login. If set then the password and username are ignored. Can be used for tokens which can expire and therefore must be read dynamically. | MailAuthenticator | |
autowiredEnabled (advanced) | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. | true | boolean |
configuration (advanced) | Sets the Mail configuration. | MailConfiguration | |
connectionTimeout (advanced) | The connection timeout in milliseconds. | 30000 | int |
contentType (advanced) | The mail message content type. Use text/html for HTML mails. | text/plain | String |
contentTypeResolver (advanced) | Resolver to determine Content-Type for file attachments. | ContentTypeResolver | |
debugMode (advanced) | Enable debug mode on the underlying mail framework. The SUN Mail framework logs the debug messages to System.out by default. | false | boolean |
ignoreUnsupportedCharset (advanced) | 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. | false | boolean |
ignoreUriScheme (advanced) | 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. | false | boolean |
javaMailProperties (advanced) | Sets the java mail options. Will clear any default properties and only use the properties provided for this method. | Properties | |
session (advanced) | Specifies the mail session that camel should use for all mail interactions. Useful in scenarios where mail sessions are created and managed by some other resource, such as a JavaEE container. When using a custom mail session, then the hostname and port from the mail session will be used (if configured on the session). | Session | |
useInlineAttachments (advanced) | Whether to use disposition inline or attachment. | false | boolean |
headerFilterStrategy (filter) | To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter header to and from Camel message. | HeaderFilterStrategy | |
password (security) | The password for login. See also setAuthenticator(MailAuthenticator). | String | |
sslContextParameters (security) | To configure security using SSLContextParameters. | SSLContextParameters | |
useGlobalSslContextParameters (security) | Enable usage of global SSL context parameters. | false | boolean |
username (security) | The username for login. See also setAuthenticator(MailAuthenticator). | String |
38.4. Endpoint Options
The Mail endpoint is configured using URI syntax:
imap:host:port
with the following path and query parameters:
38.4.1. Path Parameters (2 parameters)
Name | Description | Default | Type |
---|---|---|---|
host (common) | Required The mail server host name. | String | |
port (common) | The port number of the mail server. | int |
38.4.2. Query Parameters (66 parameters)
Name | Description | Default | Type |
---|---|---|---|
bridgeErrorHandler (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean |
closeFolder (consumer) | 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. | true | boolean |
copyTo (consumer) | 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. | String | |
decodeFilename (consumer) | If set to true, the MimeUtility.decodeText method will be used to decode the filename. This is similar to setting JVM system property mail.mime.encodefilename. | false | boolean |
delete (consumer) | 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. | false | boolean |
disconnect (consumer) | Whether the consumer should disconnect after polling. If enabled this forces Camel to connect on each poll. | false | boolean |
handleFailedMessage (consumer) | If the mail consumer cannot retrieve a given mail message, then this option allows to handle the caused exception by the consumer’s error handler. By enable the bridge error handler on the consumer, then the Camel routing error handler can handle the exception instead. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | boolean |
maxMessagesPerPoll (consumer) | 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. | int | |
mimeDecodeHeaders (consumer) | This option enables transparent MIME decoding and unfolding for mail headers. | false | boolean |
moveTo (consumer) | After processing a mail message, it can be moved to a mail folder with the given name. You can override this configuration value, with a header with the key moveTo, allowing you to move messages to folder names configured at runtime. | String | |
peek (consumer) | Will mark the javax.mail.Message as peeked before processing the mail message. This applies to IMAPMessage messages types only. By using peek the mail will not be eager marked as SEEN on the mail server, which allows us to rollback the mail message if there is an error processing in Camel. | true | boolean |
sendEmptyMessageWhenIdle (consumer) | If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead. | false | boolean |
skipFailedMessage (consumer) | If the mail consumer cannot retrieve a given mail message, then this option allows to skip the message and move on to retrieve the next mail message. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | boolean |
unseen (consumer) | Whether to limit by unseen mails only. | true | boolean |
exceptionHandler (consumer (advanced)) | To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. | ExceptionHandler | |
exchangePattern (consumer (advanced)) | Sets the exchange pattern when the consumer creates an exchange. Enum values:
| ExchangePattern | |
fetchSize (consumer (advanced)) | 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. | -1 | int |
folderName (consumer (advanced)) | The folder to poll. | INBOX | String |
mailUidGenerator (consumer (advanced)) | A pluggable MailUidGenerator that allows to use custom logic to generate UUID of the mail message. | MailUidGenerator | |
mapMailMessage (consumer (advanced)) | Specifies whether Camel should map the received mail message to Camel body/headers/attachments. If set to true, the body of the mail message is mapped to the body of the Camel IN message, the mail headers are mapped to IN headers, and the attachments to Camel IN attachment message. 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). | true | boolean |
pollStrategy (consumer (advanced)) | A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel. | PollingConsumerPollStrategy | |
postProcessAction (consumer (advanced)) | Refers to an MailBoxPostProcessAction for doing post processing tasks on the mailbox once the normal processing ended. | MailBoxPostProcessAction | |
bcc (producer) | Sets the BCC email address. Separate multiple email addresses with comma. | String | |
cc (producer) | Sets the CC email address. Separate multiple email addresses with comma. | String | |
from (producer) | The from email address. | camel@localhost | String |
lazyStartProducer (producer) | Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | false | boolean |
replyTo (producer) | The Reply-To recipients (the receivers of the response mail). Separate multiple email addresses with a comma. | String | |
subject (producer) | The Subject of the message being sent. Note: Setting the subject in the header takes precedence over this option. | String | |
to (producer) | Sets the To email address. Separate multiple email addresses with comma. | String | |
javaMailSender (producer (advanced)) | To use a custom org.apache.camel.component.mail.JavaMailSender for sending emails. | JavaMailSender | |
additionalJavaMailProperties (advanced) | Sets additional java mail properties, that will append/override any default properties that is set based on all the other options. This is useful if you need to add some special options but want to keep the others as is. | Properties | |
alternativeBodyHeader (advanced) | 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. | CamelMailAlternativeBody | String |
attachmentsContentTransferEncodingResolver (advanced) | To use a custom AttachmentsContentTransferEncodingResolver to resolve what content-type-encoding to use for attachments. | AttachmentsContentTransferEncodingResolver | |
authenticator (advanced) | The authenticator for login. If set then the password and username are ignored. Can be used for tokens which can expire and therefore must be read dynamically. | MailAuthenticator | |
binding (advanced) | Sets the binding used to convert from a Camel message to and from a Mail message. | MailBinding | |
connectionTimeout (advanced) | The connection timeout in milliseconds. | 30000 | int |
contentType (advanced) | The mail message content type. Use text/html for HTML mails. | text/plain | String |
contentTypeResolver (advanced) | Resolver to determine Content-Type for file attachments. | ContentTypeResolver | |
debugMode (advanced) | Enable debug mode on the underlying mail framework. The SUN Mail framework logs the debug messages to System.out by default. | false | boolean |
headerFilterStrategy (advanced) | To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter headers. | HeaderFilterStrategy | |
ignoreUnsupportedCharset (advanced) | 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. | false | boolean |
ignoreUriScheme (advanced) | 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. | false | boolean |
javaMailProperties (advanced) | Sets the java mail options. Will clear any default properties and only use the properties provided for this method. | Properties | |
session (advanced) | Specifies the mail session that camel should use for all mail interactions. Useful in scenarios where mail sessions are created and managed by some other resource, such as a JavaEE container. When using a custom mail session, then the hostname and port from the mail session will be used (if configured on the session). | Session | |
useInlineAttachments (advanced) | Whether to use disposition inline or attachment. | false | boolean |
idempotentRepository (filter) | A pluggable repository org.apache.camel.spi.IdempotentRepository which allows to cluster consuming from the same mailbox, and let the repository coordinate whether a mail message is valid for the consumer to process. By default no repository is in use. | IdempotentRepository | |
idempotentRepositoryRemoveOnCommit (filter) | When using idempotent repository, then when the mail message has been successfully processed and is committed, should the message id be removed from the idempotent repository (default) or be kept in the repository. By default its assumed the message id is unique and has no value to be kept in the repository, because the mail message will be marked as seen/moved or deleted to prevent it from being consumed again. And therefore having the message id stored in the idempotent repository has little value. However this option allows to store the message id, for whatever reason you may have. | true | boolean |
searchTerm (filter) | 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. | SearchTerm | |
backoffErrorThreshold (scheduler) | The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in. | int | |
backoffIdleThreshold (scheduler) | The number of subsequent idle polls that should happen before the backoffMultipler should kick-in. | int | |
backoffMultiplier (scheduler) | To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured. | int | |
delay (scheduler) | Milliseconds before the next poll. | 60000 | long |
greedy (scheduler) | If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages. | false | boolean |
initialDelay (scheduler) | Milliseconds before the first poll starts. | 1000 | long |
repeatCount (scheduler) | Specifies a maximum limit of number of fires. So if you set it to 1, the scheduler will only fire once. If you set it to 5, it will only fire five times. A value of zero or negative means fire forever. | 0 | long |
runLoggingLevel (scheduler) | The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that. Enum values:
| TRACE | LoggingLevel |
scheduledExecutorService (scheduler) | Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool. | ScheduledExecutorService | |
scheduler (scheduler) | To use a cron scheduler from either camel-spring or camel-quartz component. Use value spring or quartz for built in scheduler. | none | Object |
schedulerProperties (scheduler) | To configure additional properties when using a custom scheduler or any of the Quartz, Spring based scheduler. | Map | |
startScheduler (scheduler) | Whether the scheduler should be auto started. | true | boolean |
timeUnit (scheduler) | Time unit for initialDelay and delay options. Enum values:
| MILLISECONDS | TimeUnit |
useFixedDelay (scheduler) | Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details. | true | boolean |
password (security) | The password for login. See also setAuthenticator(MailAuthenticator). | String | |
sslContextParameters (security) | To configure security using SSLContextParameters. | SSLContextParameters | |
username (security) | The username for login. See also setAuthenticator(MailAuthenticator). | String | |
sortTerm (sort) | Sorting order for messages. Only natively supported for IMAP. Emulated to some degree when using POP3 or when IMAP server does not have the SORT capability. | SortTerm[] |
38.4.3. 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
38.4.4. Component alias names
- IMAP
- IMAPs
- POP3s
- SMTP
- SMTPs
38.4.5. 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 |
---|---|
|
|
|
|
|
|
|
|
|
|
|
|
38.5. SSL support
The underlying mail framework is responsible for providing SSL support. You 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.
38.5.1. Using the JSSE Configuration Utility
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"/>...
38.5.2. Configuring JavaMail Directly
Camel uses Jakarta 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).
38.6. 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:
The same applies for other MimeMessage headers such as recipients, so you can use a header property as To:
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.
38.7. 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);
38.8. 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.
38.9. 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");
38.10. JavaMail API (ex SUN JavaMail)
JavaMail API 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.
- JavaMail POP3 API
- JavaMail IMAP API
- And generally about the MAIL Flags
38.11. 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.
from("imap://admin@mymailserver.com?password=secret&unseen=true&delay=60000") .to("seda://mails");
38.12. 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.
38.13. 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&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=[...
38.14. 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&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 AttachmentMessage attachmentMessage = exchange.getMessage(AttachmentMessage.class); Map<String, DataHandler> attachments = attachmentMessage.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.
38.15. 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 in the source code here.
In the Camel route you then need to use this Expression in the route as shown below:
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>
You can also split the attachments as byte[] to be stored as the message body. This is done by creating the expression with boolean true
SplitAttachmentsExpression split = SplitAttachmentsExpression(true);
And then use the expression with the splitter EIP.
38.16. Using custom SearchTerm
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>
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();
38.17. Polling Optimization
The parameter maxMessagePerPoll and fetchSize allow you to restrict the number message that should be processed for each poll. These parameters should help to prevent bad performance when working with folders that contain a lot of messages. In previous versions these parameters have been evaluated too late, so that big mailboxes could still cause performance problems. With Camel 3.1 these parameters are evaluated earlier during the poll to avoid these problems.
38.18. Using headers with additional Java Mail Sender properties
When sending mails, then you can provide dynamic java mail properties for the JavaMailSender
from the Exchange as message headers with keys starting with java.smtp.
.
You can set any of the java.smtp
properties which you can find in the Java Mail documentation.
For example to provide a dynamic uuid in java.smtp.from
(SMTP MAIL command):
.setHeader("from", constant("reply2me@foo.com")); .setHeader("java.smtp.from", method(UUID.class, "randomUUID")); .to("smtp://mymailserver:1234");
This is only supported when not using a custom JavaMailSender
.
38.19. Spring Boot Auto-Configuration
When using imap with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:
<dependency> <groupId>org.apache.camel.springboot</groupId> <artifactId>camel-mail-starter</artifactId> </dependency>
The component supports 50 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
camel.component.mail.additional-java-mail-properties | Sets additional java mail properties, that will append/override any default properties that is set based on all the other options. This is useful if you need to add some special options but want to keep the others as is. The option is a java.util.Properties type. | Properties | |
camel.component.mail.alternative-body-header | 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. | CamelMailAlternativeBody | String |
camel.component.mail.attachments-content-transfer-encoding-resolver | To use a custom AttachmentsContentTransferEncodingResolver to resolve what content-type-encoding to use for attachments. The option is a org.apache.camel.component.mail.AttachmentsContentTransferEncodingResolver type. | AttachmentsContentTransferEncodingResolver | |
camel.component.mail.authenticator | The authenticator for login. If set then the password and username are ignored. Can be used for tokens which can expire and therefore must be read dynamically. The option is a org.apache.camel.component.mail.MailAuthenticator type. | MailAuthenticator | |
camel.component.mail.autowired-enabled | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. | true | Boolean |
camel.component.mail.bcc | Sets the BCC email address. Separate multiple email addresses with comma. | String | |
camel.component.mail.bridge-error-handler | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | Boolean |
camel.component.mail.cc | Sets the CC email address. Separate multiple email addresses with comma. | String | |
camel.component.mail.close-folder | 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. | true | Boolean |
camel.component.mail.configuration | Sets the Mail configuration. The option is a org.apache.camel.component.mail.MailConfiguration type. | MailConfiguration | |
camel.component.mail.connection-timeout | The connection timeout in milliseconds. | 30000 | Integer |
camel.component.mail.content-type | The mail message content type. Use text/html for HTML mails. | text/plain | String |
camel.component.mail.content-type-resolver | Resolver to determine Content-Type for file attachments. The option is a org.apache.camel.component.mail.ContentTypeResolver type. | ContentTypeResolver | |
camel.component.mail.copy-to | 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. | String | |
camel.component.mail.debug-mode | Enable debug mode on the underlying mail framework. The SUN Mail framework logs the debug messages to System.out by default. | false | Boolean |
camel.component.mail.decode-filename | If set to true, the MimeUtility.decodeText method will be used to decode the filename. This is similar to setting JVM system property mail.mime.encodefilename. | false | Boolean |
camel.component.mail.delete | 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. | false | Boolean |
camel.component.mail.disconnect | Whether the consumer should disconnect after polling. If enabled this forces Camel to connect on each poll. | false | Boolean |
camel.component.mail.enabled | Whether to enable auto configuration of the mail component. This is enabled by default. | Boolean | |
camel.component.mail.fetch-size | 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. | -1 | Integer |
camel.component.mail.folder-name | The folder to poll. | INBOX | String |
camel.component.mail.from | The from email address. | camel@localhost | String |
camel.component.mail.handle-failed-message | If the mail consumer cannot retrieve a given mail message, then this option allows to handle the caused exception by the consumer’s error handler. By enable the bridge error handler on the consumer, then the Camel routing error handler can handle the exception instead. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | Boolean |
camel.component.mail.header-filter-strategy | To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter header to and from Camel message. The option is a org.apache.camel.spi.HeaderFilterStrategy type. | HeaderFilterStrategy | |
camel.component.mail.ignore-unsupported-charset | 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. | false | Boolean |
camel.component.mail.ignore-uri-scheme | 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. | false | Boolean |
camel.component.mail.java-mail-properties | Sets the java mail options. Will clear any default properties and only use the properties provided for this method. The option is a java.util.Properties type. | Properties | |
camel.component.mail.java-mail-sender | To use a custom org.apache.camel.component.mail.JavaMailSender for sending emails. The option is a org.apache.camel.component.mail.JavaMailSender type. | JavaMailSender | |
camel.component.mail.lazy-start-producer | Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | false | Boolean |
camel.component.mail.map-mail-message | Specifies whether Camel should map the received mail message to Camel body/headers/attachments. If set to true, the body of the mail message is mapped to the body of the Camel IN message, the mail headers are mapped to IN headers, and the attachments to Camel IN attachment message. 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). | true | Boolean |
camel.component.mail.mime-decode-headers | This option enables transparent MIME decoding and unfolding for mail headers. | false | Boolean |
camel.component.mail.move-to | After processing a mail message, it can be moved to a mail folder with the given name. You can override this configuration value, with a header with the key moveTo, allowing you to move messages to folder names configured at runtime. | String | |
camel.component.mail.password | The password for login. See also setAuthenticator(MailAuthenticator). | String | |
camel.component.mail.peek | Will mark the javax.mail.Message as peeked before processing the mail message. This applies to IMAPMessage messages types only. By using peek the mail will not be eager marked as SEEN on the mail server, which allows us to rollback the mail message if there is an error processing in Camel. | true | Boolean |
camel.component.mail.reply-to | The Reply-To recipients (the receivers of the response mail). Separate multiple email addresses with a comma. | String | |
camel.component.mail.session | Specifies the mail session that camel should use for all mail interactions. Useful in scenarios where mail sessions are created and managed by some other resource, such as a JavaEE container. When using a custom mail session, then the hostname and port from the mail session will be used (if configured on the session). The option is a javax.mail.Session type. | Session | |
camel.component.mail.skip-failed-message | If the mail consumer cannot retrieve a given mail message, then this option allows to skip the message and move on to retrieve the next mail message. The default behavior would be the consumer throws an exception and no mails from the batch would be able to be routed by Camel. | false | Boolean |
camel.component.mail.ssl-context-parameters | To configure security using SSLContextParameters. The option is a org.apache.camel.support.jsse.SSLContextParameters type. | SSLContextParameters | |
camel.component.mail.subject | The Subject of the message being sent. Note: Setting the subject in the header takes precedence over this option. | String | |
camel.component.mail.to | Sets the To email address. Separate multiple email addresses with comma. | String | |
camel.component.mail.unseen | Whether to limit by unseen mails only. | true | Boolean |
camel.component.mail.use-global-ssl-context-parameters | Enable usage of global SSL context parameters. | false | Boolean |
camel.component.mail.use-inline-attachments | Whether to use disposition inline or attachment. | false | Boolean |
camel.component.mail.username | The username for login. See also setAuthenticator(MailAuthenticator). | String | |
camel.dataformat.mime-multipart.binary-content | Defines whether the content of binary parts in the MIME multipart is binary (true) or Base-64 encoded (false) Default is false. | false | Boolean |
camel.dataformat.mime-multipart.enabled | Whether to enable auto configuration of the mime-multipart data format. This is enabled by default. | Boolean | |
camel.dataformat.mime-multipart.headers-inline | Defines whether the MIME-Multipart headers are part of the message body (true) or are set as Camel headers (false). Default is false. | false | Boolean |
camel.dataformat.mime-multipart.include-headers | A regex that defines which Camel headers are also included as MIME headers into the MIME multipart. This will only work if headersInline is set to true. Default is to include no headers. | String | |
camel.dataformat.mime-multipart.multipart-sub-type | Specify the subtype of the MIME Multipart. Default is mixed. | mixed | String |
camel.dataformat.mime-multipart.multipart-without-attachment | Defines whether a message without attachment is also marshaled into a MIME Multipart (with only one body part). Default is false. | false | Boolean |