The code here is now obsolete. It has been replaced by "native" support in the CogServer. A JSON+websoockets interface is provided on port 18080. See the websockets demo in the CogServer examples directory. The code below was an older, earlier attempt to prove WebSockets.
This is a simple project that provides Websockets access to the OpenCog AtomSpace to execute pattern matching queries. It also allows users to create multiple atomspaces and access them separately. Users can use a JSON config file to specify the id and the directory containing the atomese code to load. An example config looks like the following:
[
{
"id": "asp1",
"pathDir": "/path/to/atomese/code/"
},
{
"id": "asp2",
"pathDir": "/path/to/another/atomese/code"
}
]
You can use the above JSON to start the server like this:
$ atom_server --config /path/to/setting.json
This will create to AtomSpaces with idsasp1
& asp2
and can be accessed via WebSockets. An example Javascript to
access an AtomSpace containing the sample_dataset.scm
can be:
<!DOCTYPE html>
<html>
<body>
<script type="text/javascript">
var ws = new WebSocket("ws://localhost:9001/asp1"); //endpoint to access asp1 AtomSpace
var patt = `(GetLink
(EvaluationLink
(Predicate "is_part")
(ListLink
(Concept "A")
(Variable "$x"))))`; //this pattern searches for all ConceptNodes where A has
//is_part relationship
console.log("initialized websocket");
ws.onmessage = function(evt) {
if(evt.data !== "eof"){
console.log("received message");
document.getElementById("res").innerHTML += "<p>" + evt.data + "</p>";
console.log(evt);
} else {
console.log("End of message received");
}
};
ws.onopen = function() {
console.log("connected");
//Send the pattern to be executed
ws.send(patt);
};
ws.onclose = function() {
console.log("closed websocket");
}
</script>
<p id="res">Results are: </p>
</body>
</html>
This project depends on the following libraries:
- AtomSpace
- Boost
- uWebSockets -- make sure you check out the
v18
branch- Note: uSockets library is needed which uWebSockets depends on it. After building the uSockets, you need to copy the static library to a library search path (e.g /usr/local/lib)
- nlohmann_json
- Agi-bio - this is OPTIONAL and will be required if you are working with bio related atomspace
$ cd atomspace_server
$ mkdir build && cd build
$ cmake ..
$ make
$ make install
This project is inspired by the already existing CogServer. However , this project is intended provide to a very simple, high-level access to the AtomSpace to run pattern matching queries via Websockets and the ability to load multiple atomspaces at once. It doesn't support the use Scheme or Python REPL to access an AtomSpace and you can't do anything complex(yet) such as job monitoring, loading other scheme modules ..etc that you can do with CogServer. If you are looking for such functionality please check out CogServer.