This is an automated email from the ASF dual-hosted git repository.
davsclaus pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/camel.git
The following commit(s) were added to refs/heads/main by this push:
new eff41a2 CAMEL-16861: Polished SpEL language
eff41a2 is described below
commit eff41a237e68d572c003c0d2a1d5c4933c1a0f67
Author: Claus Ibsen <claus.ib...@gmail.com>
AuthorDate: Tue Sep 14 10:30:39 2021 +0200
CAMEL-16861: Polished SpEL language
---
.../camel-mvel/src/main/docs/mvel-language.adoc | 2 +
.../camel-spring/src/main/docs/spel-language.adoc | 133 ++++++++++-----------
.../org/apache/camel/language/spel/RootObject.java | 13 ++
3 files changed, 75 insertions(+), 73 deletions(-)
diff --git a/components/camel-mvel/src/main/docs/mvel-language.adoc
b/components/camel-mvel/src/main/docs/mvel-language.adoc
index e315ff0..ff5b577 100644
--- a/components/camel-mvel/src/main/docs/mvel-language.adoc
+++ b/components/camel-mvel/src/main/docs/mvel-language.adoc
@@ -51,6 +51,8 @@ The MVEL language supports 1 options, which are listed below.
== Variables
+The following Camel related variables are made available:
+
[width="100%",cols="10%,10%,80%",options="header",]
|=======================================================================
|Variable |Type |Description
diff --git a/components/camel-spring/src/main/docs/spel-language.adoc
b/components/camel-spring/src/main/docs/spel-language.adoc
index b147142..b64ddff 100644
--- a/components/camel-spring/src/main/docs/spel-language.adoc
+++ b/components/camel-spring/src/main/docs/spel-language.adoc
@@ -16,41 +16,10 @@ to be used as an Expression or Predicate in the DSL or XML
Configuration.
[NOTE]
====
It is recommended to use SpEL in Spring runtimes. However, you can
-use SpEL in other runtimes (there may be functionality SpEL cannot do when not
running in a Spring runtime)
+use SpEL in other runtimes (there are some functionality which SpEL can only
do in a Spring runtime)
====
-== Variables
-
-The following variables are available in expressions and predicates written in
SpEL:
-
-[width="100%",cols="10%,10%,80%",options="header",]
-|===
-|Variable |Type |Description
-
-|this |Exchange |the Exchange is the root object
-
-|exchange |Exchange |the Exchange object
-
-|exception |Throwable |the Exchange exception (if any)
-
-|exchangeId |String |the exchange id
-
-|fault |Message |the Fault message (if any)
-
-|body |Object | The IN message body.
-
-|request |Message |the exchange.in message
-
-|response |Message |the exchange.out message (if any)
-
-|properties |Map |the exchange properties
-
-|property(name) |Object |the property by the given name
-
-|property(name, type) |Type |the property by the given name as the given type
-|===
-
-== Options
+== SpEL Options
// language options: START
The SpEL language supports 1 options, which are listed below.
@@ -64,7 +33,53 @@ The SpEL language supports 1 options, which are listed below.
|===
// language options: END
-== Samples
+== Variables
+
+The following Camel related variables are made available:
+
+[width="100%",cols="10%,10%,80%",options="header",]
+|=======================================================================
+|Variable |Type |Description
+|*this* |Exchange |the Exchange is the root object
+|context |CamelContext |the CamelContext
+|exchange |Exchange |the Exchange
+|exchangeId |String |the exchange id
+|exception |Throwable |the Exchange exception (if any)
+|request |Message |the message
+|message |Message |the message
+|headers |Map |the message headers
+|header(name) |Object |the message header by the given name
+|header(name, type) |Type |the message header by the given name as the given
type
+|properties |Map |the exchange properties
+|property(name) |Object |the exchange property by the given name
+|property(name, type) |Type |the exchange property by the given name as the
given type
+|=======================================================================
+
+== Example
+
+You can use SpEL as an expression for
xref:{eip-vc}:eips:recipientList-eip.adoc[Recipient
+List] or as a predicate inside a xref:{eip-vc}:eips:filter-eip.adoc[Message
+Filter]:
+
+[source,xml]
+----
+<route>
+ <from uri="direct:foo"/>
+ <filter>
+ <spel>#{request.headers.foo == 'bar'}</spel>
+ <to uri="direct:bar"/>
+ </filter>
+</route>
+----
+
+And the equivalent in Java DSL:
+
+[source,java]
+----
+from("direct:foo")
+ .filter().spel("#{request.headers.foo == 'bar'}")
+ .to("direct:bar");
+----
=== Expression templating
@@ -82,9 +97,9 @@ from("direct:example")
.to("mock:result");
----
-In the route above, notice spel is a static method which we need to
+In the route above, notice `spel` is a static method which we need to
import from `org.apache.camel.language.spel.SpelExpression.spel`, as we
-use spel as an Expression passed in as a parameter
+use `spel` as an Expression passed in as a parameter
to the `setBody` method. Though if we use the fluent API we can do this
instead:
@@ -96,10 +111,9 @@ from("direct:example")
----
Notice we now use the `spel` method from the `setBody()` method. And
-this does not require us to static import the spel method from
-`org.apache.camel.language.spel.SpelExpression.spel`.
+this does not require us to static import the `spel` method.
-And sent a message with the string "World" in the body, and a header
+Then we send a message with the string "World" in the body, and a header
"dayOrNight" with value "day":
[source,java]
@@ -112,50 +126,23 @@ day"_
=== Bean integration
-You can reference beans defined in the Registry
-(most likely an `ApplicationContext`) in your SpEL expressions. For
-example if you have a bean named "foo" in your `ApplicationContext` you
-can invoke the "bar" method on this bean like this:
+You can reference beans defined in the xref:manual::registry.adoc[Registry]
+in your SpEL expressions. For example if you have a bean named "foo"
+registered in the Spring `ApplicationContext`. You
+can then invoke the "bar" method on this bean like this:
[source,text]
----
#{@foo.bar == 'xyz'}
----
-=== SpEL in enterprise integration patterns
-
-You can use SpEL as an expression for
xref:{eip-vc}:eips:recipientList-eip.adoc[Recipient
-List] or as a predicate inside a xref:{eip-vc}:eips:filter-eip.adoc[Message
-Filter]:
-
-[source,xml]
-----
-<route>
- <from uri="direct:foo"/>
- <filter>
- <spel>#{request.headers.foo == 'bar'}</spel>
- <to uri="direct:bar"/>
- </filter>
-</route>
-----
-
-And the equivalent in Java DSL:
-
-[source,java]
-----
-from("direct:foo")
- .filter().spel("#{request.headers.foo == 'bar'}")
- .to("direct:bar");
-----
== Loading script from external resource
-*Since Camel 2.11*
-
You can externalize the script and have Camel load it from a resource
-such as `"classpath:"`, `"file:"`, or `"http:"`. +
- This is done using the following syntax: `"resource:scheme:location"`,
-eg to refer to a file on the classpath you can do:
+such as `"classpath:"`, `"file:"`, or `"http:"`.
+This is done using the following syntax: `"resource:scheme:location"`,
+e.g. to refer to a file on the classpath you can do:
[source,java]
----
diff --git
a/components/camel-spring/src/main/java/org/apache/camel/language/spel/RootObject.java
b/components/camel-spring/src/main/java/org/apache/camel/language/spel/RootObject.java
index 6d971a1..8f6c4ce 100644
---
a/components/camel-spring/src/main/java/org/apache/camel/language/spel/RootObject.java
+++
b/components/camel-spring/src/main/java/org/apache/camel/language/spel/RootObject.java
@@ -73,4 +73,17 @@ public final class RootObject {
public <T> T getProperty(String name, Class<T> type) {
return exchange.getProperty(name, type);
}
+
+ public Map<String, Object> getHeaders() {
+ return exchange.getMessage().getHeaders();
+ }
+
+ public Object getHeader(String name) {
+ return exchange.getMessage().getHeader(name);
+ }
+
+ public <T> T getHeader(String name, Class<T> type) {
+ return exchange.getMessage().getHeader(name, type);
+ }
+
}
