Register websocket endpoints for /mapping/ for /mapping/* servlets

[Artur-]

Another attempt for #2316

Only adds a root mapping for the servlet and not the unsupported /{path1}/{path2}/ type paths

[jfarcand]

@Artur- I did try that here

3a6a9bc

But it regressed existing apps as well.

[Artur-]

Interesting... in what way as / or /servlet/ should be valid mappings?

[jfarcand]

@Artur- Actually do you have a test/app I can play with that fail to deploy properly? The issue here is we may need to bump the release to 2.5 to prevent breaking compatibility.

[Artur-]

Have not tested with atmosphere samples but I guess if you deploy a servlet to /* and try to use / for the websocket connection, it won’t work

[fenik17]

Static analizer in IntelliJ IDEA found that regexp for cleaning servlet path contains unclosed character class:

atmosphere/modules/runtime/src/main/java/org/atmosphere/util/IOUtils.java

Line 59 in e0cdc9f

private final static Pattern SERVLET_PATH_PATTERN = Pattern.compile("([\\/]?[\\w-[.]]+|[\\/]\\*\\*)+");

@Artur- you can try to use this fixed pattern:

private final static Pattern SERVLET_PATH_PATTERN = Pattern.compile("([/]?[a-zA-Z_0-9.]+?|[/]\\*\\*)+");

Does this solve your issue?

[fenik17]

@Artur- ping

[fenik17]

@Artur-
copy of my question from #2331:

Can you describe the core problem that you are trying to solve?

We can looking for other solutions. Or let me close this PR.

[Artur-]

The core problem: Deploying a servlet using "/*" should deploy a websocket endpoint at /. Similarly, deployingn a servlet as /foo/* should deploy a websocket endpoint at /foo/

[fenik17]

should deploy

But where does this requirement come from?
From javadoc of the ServerEndpointConfig.Builder' constructor [1]:

path - The URI or URI template where the endpoint will be deployed. A trailing "/" will be ignored and the path must begin with /.

This means that, as a minimum, there is no difference beetwen /foo and /foo/.

[1] https://docs.oracle.com/javaee/7/api/javax/websocket/server/ServerEndpointConfig.Builder.html#create-java.lang.Class-java.lang.String-

[Artur-]

JSR356AsyncSupport.java:

if (servletPath == null) {
    servletPath = IOUtils.guestServletPath(config);
    if (servletPath.equals("") || servletPath.equals("/") || servletPath.equals("/*")) {
        servletPath = PATH +"}";
    }
}

For /*, IOUtils.guestServletPath(config); returns "" and servletPath becomes /{path}. This matches /something but not /. This is quite unexpected.

Might be that a /foo/* mapping actually works correctly with current master. I can't see directly why it would not, as servletPath will then become /foo, without any initially added {path}