docs/user-manual/modules/faq/pages/how-to-use-a-dynamic-uri-in-to.adoc

[[HowtouseadynamicURIinto-HowtouseadynamicURIinto]]
= How to use a dynamic URI in `to()`

A dynamic URI is an endpoint URI that varies depending on inflight
routing information, such as Exchange properties, message headers, the
body, the Camel Context, etc.

For example, if you're using a Freemarker producer and the template
location is provided inside the current message, you might expect the
following code to work, *but it will not*.

[WARNING]
====
*This is not valid code*

This snippet is not valid code. Read on.
====

[source,java]
----
.to("freemarker://templateHome/${body.templateName}.ftl")
----

In this case, you must use an EIP (Enterprise Integration Pattern) that
is capable of computing a dynamic URI using
an xref:ROOT:expression.adoc[Expression], such as
the xref:{eip-vc}:eips:toD-eip.adoc[ToD] or xref:{eip-vc}:eips:recipientList-eip.adoc[Recipient List] EIP pattern.

[TIP]
====
*This is valid code*

This snippet is valid code.
====

To fix the above problem we can use either toD or recipientList.
Using toD is easier as shown below:

[source,java]
----
.toD("freemarker://templateHome/${body.templateName}.ftl")
----

When using recipient list:
[source,java]
----
.recipientList(simple("freemarker://templateHome/${body.templateName}.ftl"))
----