Camel file uri using property - properties

Question

I'm trying to use property file for routing from folder :
My property file has some property :
from.file = D:/Develop/resources
and I want to use it in camel context xml as file routing,
I tried:
<camel:route id="Main-Route">
<camel:from uri="file:${from.file}" />
<camel:to uri="seda:fooQueue" />
</camel:route>
But camel throws me exception :
Dynamic expressions with ${ } placeholders is not allowed. Use the fileName option to set the dynamic expression.
How can I do this ?

Answer 1

In Camel, you use {{property}} to inject properties in your routes.
Please read more here http://camel.apache.org/properties.html.
Your example would change to:
<camel:route id="Main-Route">
<camel:from uri="file:{{from.file}}" />
<camel:to uri="seda:fooQueue" />
</camel:route>
You also need to tell Camel where it can find your properties file. From the link above:
Spring XML offers two variations to configure. You can define a spring bean as a PropertiesComponent which resembles the way done in Java DSL. Or you can use the tag.
<bean id="properties" class="org.apache.camel.component.properties.PropertiesComponent">
<property name="location" value="classpath:com/mycompany/myprop.properties"/>
</bean>
Using the tag makes the configuration a bit more fresh such as:
<camelContext ...>
<propertyPlaceholder id="properties" location="com/mycompany/myprop.properties"/>
</camelContext>

Answer 2

In file component of apache camel,the starting directory should not contain dynamic expressions. If you want to provide dynamic starting directory also,you can set the whole path into CamelFileName header of file component from properties file with fileComponent defined as <to uri="file://">

Answer 3

the problem with this is that for reading place holder as :
${some-property} for some bean for example :
<bean id="bean" class="">
<property name="field Constructor" value="${some.property}" />
</bean>
I get error.
Solved it by defining also PropertyPlaceholderConfigurer:
<bean id="proprty" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<value>file:/D:/Proj/resources/myprop.properties
</value>
</bean>
<bean id="beanId" class="com.viewlinks.eim.properties.MyBean">
<property name="fieldConstructor" value="${some.property}" />
</bean>
<camel:camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
<propertyPlaceholder id="properties" location="file:/D:/Proj/resources/myprop.properties"/>
<camel:route id="Main-Route">
<camel:from uri="file:{{from.file}}" />
<camel:to uri="file:{{to.file}}" />
</camel:route>
</camel:camelContext>