Re: Understanding continuations

[Christopher Oliver]

Try setting a breakpoint on xmlForm.js, line 178:

174        this._sendView(uri, k);
175        // _sendView creates a continuation, the invocation of which
176        // will return right here: it is used to implement
177        // <xf:submit continuation="forward">
178        if (this.dead || cocoon.request == null) {
179            // this continuation has been invalidated
180            handleInvalidContinuation();
181            suicide();
182        }
That is where you will jump to when jswk.continuation(jswk) is called.

Hope this helps,

Chris

Ugo Cei wrote:
Christopher Oliver wrote:

What do you mean by "invalid continuation error"?


I mean that the handleInvalidContinuation function in system.js is 
called and it redirects to my handler page ... BUT ... the "id" 
parameter is empty!

What I'm doing is this: I have an XMLForm with a submit button that is 
like the following:

<xf:submit id="next" continuation="forward">
    <xf:caption>OK</xf:caption>
</xf:submit>
After the XMLForm transformation, this is sent to the browser as:

<input value="OK" type="submit" 
name="cocoon-action-0d3e48210a8f347652091a6d463f6470716d154b" 
continuation="forward">

I've added a few debug statements in xmlForm.js to see what's going on:

    var command = getCommand();
    log.debug("xmlForm: command = " + command); //DEBUG
    if (command != undefined) {
        // invoke a continuation
        var continuationsMgr =
cocoon.componentManager.lookup(Packages.org.apache.cocoon.components.flow.ContinuationsManager.ROLE); 

        var wk = continuationsMgr.lookupWebContinuation(command);
        wk.display(); // DEBUG
        cocoon.componentManager.release(continuationsMgr);
        if (wk != null) {
            var jswk = wk.userObject;
            jswk.display(); // DEBUG
            jswk.continuation(jswk);
            // note: not reached
        }
        handleInvalidContinuation(command);
        return;
    }
And these are the contents of flow.log:

DEBUG   (2003-03-28) 12:34.24:737   [flow] (/cefalee/arruolamento) 
Thread-9/JSLog: xmlForm: command = 0d3e48210a8f347652091a6d463f6470716d154b
DEBUG   (2003-03-28) 12:34.24:739   [flow] (/cefalee/arruolamento) 
Thread-9/WebContinuation:
WK: Tree
WK: WebContinuation 0d3e48210a8f347652091a6d463f6470716d154b ExpireTime 
[1048854377943]
DEBUG   (2003-03-28) 12:34.24:741   [flow] (/cefalee/arruolamento) 
Thread-9/WebContinuation:
WK: Tree
WK: WebContinuation 0d3e48210a8f347652091a6d463f6470716d154b ExpireTime 
[1048854377943]

So it looks like the command is correct and both wk and jswk are valid 
continuations, but the handleInvalidContinuation handler is always 
called and with a null id! I'd like to debug this, but the debugger is 
not able to step into the "jswk.contiunation(jswk)" call.

What is stranger is that I have another application that is using the 
same Cocoon version (straight out of CVS this morning) and the same 
techniques for form handling and this one works! I've been staring at 
the code for 4 hours and still cannot see what is different between the 
two. :-(

    Ugo