Here is a reproducer using the maven archetype:
https://github.com/artnaseef/camel-invalid-content-encoding
Art
On Fri, Feb 16, 2024 at 3:12 PM Arthur Naseef <artnas...@apache.org> wrote:
>
> Looking into an integration that was updated from camel v2 to v4, and having
> problems with outbound "http" component requests being rejected downstream
> due to an invalid Content-Encoding field.
>
> The request is including the following header:
>
> Content-Encoding: us-ascii
>
>
> Based on research, this is invalid. Content-Encoding does not accept charset
> names. The Camel v2 version of the project does not set Content-Encoding.
> No functional changes were made to the route - only necessary changes to
> update to v4.
>
> After digging through the Camel code with the debugger and comparing the
> original version of the integration and the updated one, I tracked down the
> code in HttpProducer that used to set chartset but now sets encoding in the
> StringEntity class. Below is a minimal program that reproduces the issue.
>
> // Sample route that incorrectly generates Content-Encoding: UTF-8
>
> public static void main(String[] args) {
> org.apache.camel.CamelContext camelContext = new
> org.apache.camel.impl.DefaultCamelContext();
>
> try {
> camelContext.addRoutes(new RouteBuilder() {
> @Override
> public void configure() throws Exception {
> from("direct:AAA")
> .setProperty(Exchange.CHARSET_NAME, constant("UTF-8"))
> .to("http://localhost:9999/redacted/endpoint/path";)
> ;
> }
> }
> );
>
> camelContext.start();
> camelContext.createProducerTemplate().sendBody("direct:AAA", "");
> Thread.sleep(2000);
> } catch (Exception e) {
> e.printStackTrace();
> }
> }
>
> To test:
>
> 1. run nc -l 0.0.0.0 9999
>
> 2. compile and run that code (I personally used Intellij to run it out of
> another class that already had all the necessary dependencies to run it)
>
> 3. profit (notice the Content-Encoding header)
>
>
> More Details...
>
> Camel v2
> Here is a little more detail on the history behind this change:
>
> In httpcore-4.4.15 the following constructor was being used by camel:
>
> public StringEntity(final String string, final String charset)
>
>
> Note the "charset" argument. Here is the Camel HttpProducer line that calls
> it:
>
> StringEntity entity = new StringEntity((String) data, charset);
>
>
> Camel v4
> In httpcore5-5.2.1, the following constructor is not being used by camel:
>
> public StringEntity(
> final String string, final ContentType contentType, final String
> contentEncoding, final boolean chunked) {
>
>
> Note the lack of a "charset" argument. Here is the Camel HttpProducer line
> that calls it:
>
> answer = new StringEntity(content, contentType, charset, false);
>
>
> It appears the following commit changed the call to the StringEntity
> constructor in HttpProducer:
>
> c33a140ce51aa9bc9a8205429b78e00a39041967
>
>
> Finding which versions contain that commit:
>
> $ git tag --contains c33a140ce51aa9bc9a8205429b78e00a39041967
>
> camel-4.0.0
>
> camel-4.0.0-M3
>
> camel-4.0.0-RC1
>
> camel-4.0.0-RC2
>
> camel-4.0.1
>
> camel-4.0.2
>
> camel-4.0.3
>
> camel-4.1.0
>
> camel-4.2.0
>
> camel-4.3.0
>
>
> I would submit a PR to fix it if I knew how to correctly obtain the desired
> result - that is, that both the charset and content-encoding are set on the
> StringEntity.
>
> Art
>
