Race condition in Client

[Hagen]

Next bug:

The way I read the API is that I can use one instance of
node.http.Client and issue several requests. However, these requests
are not synchronized, i.e. if they overlap, I do get:

http.js:390: Socket is not open for writing
connection.send(out[0], out[1]);

But thanks to the asynchronous nature of node.js, it's almost
impossible to do the synchronization myself. Do you consider this a
bug in node.js? If no, reusing a client is almost impossible and I
will have to resort to calling new node.http.Client every time, which
in turn will probably cause a new connection instead of pipelining the
requests on a single connection (which I was expecting).

[ry]

Hi Hagen,

> The way I read the API is that I can use one instance of
> node.http.Client and issue several requests. However, these requests
> are not synchronized, i.e. if they overlap, I do get:

I don't understand. What do you mean by overlap? http.Client ought to
queue the requests and issue them sequentially. At the moment there is
no pipelining, it restarts the connection after each response - but
that will hopefully be added in the future. (I also want to allow for
the possibility of using up to 2 connections per http.Client to issue
multiple requests at a time.)

> http.js:390: Socket is not open for writing
> connection.send(out[0], out[1]);

It's probably a bug. Can you show me how to reproduce?

ry

[Hagen Overdick]

> http.js:390: Socket is not open for writing
>         connection.send(out[0], out[1]);

It's probably a bug. Can you show me how to reproduce?

var client = new node.http.Client(5984);

function fetch(data) {

return {

execute : function(groupHandler) {

var fetchCounter = 0;

for (var key in data) {

if (data.hasOwnProperty(key)) {

var job = data[key];

var path = job[0];

var callHandler = job[1];

fetchCounter += 1;

client.get(path).finish(function(response) {

puts("Finishing request to " + path);

response.setBodyEncoding("utf8");

var result = "";

response.onBody = function(chunk) {

result += chunk;

};

response.onBodyComplete = function() {

data[key] = callHandler(response, result);

fetchCounter -= 1;

if (fetchCounter === 0) {

puts("Group Handler");

groupHandler(data);

}

};

});

}

};

}

};

}

fetch({

foo : [

"/", 

function(response,result) {

return result;

}

]

}).execute(function(result) {

fetch({

foo : [

"/", 

function(response,result) {

return result;

}

]

}).execute(function(result) {

puts("Success");

});

});

---

brickmirror:proxy sixtus$ node /Users/sixtus/temp/clientbug.js 

http.js:390: Socket is not open for writing

Finishing request to /

        connection.send(out[0], out[1]);

                   ^

---

Creating a new client helps.

 

[ry]

Hi Hagen:

Thanks for pointing this out. It looks like a bug. I'll check it out
tomorrow.

ry

[ryan dahl]

On Mon, Jun 15, 2009 at 2:01 PM, Hagen<six...@gmail.com> wrote:
>
> Next bug:
>
> The way I read the API is that I can use one instance of
> node.http.Client and issue several requests. However, these requests
> are not synchronized, i.e. if they overlap, I do get:
>
> http.js:390: Socket is not open for writing
>        connection.send(out[0], out[1]);
>

Fixed in d77f75774516fc9dfefe6c6523a94960df5100b5