The provided code is a Node.js module for a Jupyter kernel that handles messages between the kernel and the front-end, including setting up sockets, sending responses, and handling incoming messages.
Alternatively, you can break it down into two sentences:
The code initializes the kernel by setting up sockets, binding them to the kernel, and sending an idle status message back to the front-end. It also handles incoming messages from the front-end, sending responses and handling different message types, including control, shell, and stdin messages.
do_init: (kernel, config) => {
console.log('starting wire sockets');
return setupSockets(config)
.then(bindSockets)
.then(() => kernel.meta_kernel.do_init(kernel, config))
.then(() => this.do_respond(kernel, {
status: {execution_state: 'idle'}
}));
},
do_respond: (kernel, message) => {
var result = {};
var msg_type = Object.keys(message)[0];
result[msg_type] = {content: message[msg_type]};
return wireRespond(kernel, result);
},
do_message: wireMessage,
// TODO: bubble response messages from child to front-end
function bindSockets(sockets) {
console.log('connecting sockets');
this.sockets = sockets;
sockets.heartbeat.on('message', sockets.heartbeat.send);
[sockets.control, sockets.shell, sockets.stdin]
.forEach(socket => socket.on('message', addCB.bind(
null,
parseMessage,
parsed => this.do_message(this, parsed))))
// iopub appears to be write to only
}
function wireRespond(kernel, message) {
console.log(`response`, message);
var msg_type = Object.keys(message)[0];
var encoded = collapseMessage(kernel.kernel_config.key, message);
if(msg_type === 'shutdown_reply')
kernel.sockets.control.send(encoded);
else if(msg_type.substr(-6) === '_reply')
kernel.sockets.shell.send(encoded);
else if(msg_type === 'input_request')
kernel.sockets.stdin.send(encoded);
else
kernel.sockets.iopub.send(encoded);
}
function wireMessage(kernel, message) {
var msg_type = Object.keys(message)[0];
console.log(message);
// TODO: need to pass arguments, that's why callback was used
// TODO: add execution count recorder, also to do_respond maybe
/*
kernel.do_respond = (message) => kernel.do_respond(
kernel, message,
// assign the responder
var result = {};
var execution_count = Object.values(message)[0].execution_count;
delete Object.values(message)[0].execution_count;
result[Object.keys(message)[0]] = {
execution_count,
content: Object.values(message)[0],
respond: responders[execution_count]
};
*/
nativeMetaKernel.prototype.do_message(Object.assign({}, kernel, {
do_respond: (response) => {
var result = {};
var res_type = Object.keys(response)[0];
result[res_type] = {
parent: message[msg_type].header,
metadata: message[msg_type].metadata,
content: response[res_type]
};
return wireRespond(kernel, result);
}
}), message);
}
class Kernel {
/**
* Initialize kernel and setup sockets.
*
* @param {Object} kernel The kernel instance.
* @param {Object} config The configuration object.
*/
do_init(kernel, config) {
console.log('Starting wire sockets...');
return setupSockets(config)
.then(sockets => this.bindSockets(sockets))
.then(() => kernel.meta_kernel.do_init(kernel, config))
.then(() => this.do_respond(kernel, { status: { execution_state: 'idle' } }));
}
/**
* Respond to kernel message.
*
* @param {Object} kernel The kernel instance.
* @param {Object} message The message object.
* @returns {Promise} The response promise.
*/
do_respond(kernel, message) {
const { [msg_type]: content } = message;
return this.wireRespond(kernel, { [msg_type]: { content } });
}
/**
* Handle message sent to kernel.
*
* @param {Object} kernel The kernel instance.
* @param {Object} message The message object.
* @returns {Promise} The response promise.
*/
do_message(kernel, message) {
return nativeMetaKernel.prototype.do_message(Object.assign({}, kernel, {
do_respond: (response) => {
const { [res_type]: content } = response;
return this.wireRespond(kernel, {
[res_type]: {
parent: message[res_type].header,
metadata: message[res_type].metadata,
content
}
});
}
}), message);
}
/**
* Bind sockets to kernel.
*
* @param {Object} sockets The socket object.
*/
bindSockets(sockets) {
console.log('Connecting sockets...');
this.sockets = sockets;
sockets.heartbeat.on('message', () => sockets.heartbeat.send({}));
[sockets.control, sockets.shell, sockets.stdin]
.forEach(socket => socket.on('message', (data) => this.parseMessage(data, this.do_message.bind(this))));
}
/**
* Send response to kernel.
*
* @param {Object} kernel The kernel instance.
* @param {Object} message The response object.
* @returns {Promise} The response promise.
*/
wireRespond(kernel, message) {
console.log(`Response:`, message);
const msg_type = Object.keys(message)[0];
const encoded = this.collapseMessage(kernel.kernel_config.key, message);
if (msg_type ==='shutdown_reply') {
kernel.sockets.control.send(encoded);
} else if (msg_type.endsWith('_reply')) {
kernel.sockets.shell.send(encoded);
} else if (msg_type === 'input_request') {
kernel.sockets.stdin.send(encoded);
} else {
kernel.sockets.iopub.send(encoded);
}
}
/**
* Parse message and handle accordingly.
*
* @param {Object} data The message data.
* @param {Function} callback The callback function.
*/
parseMessage(data, callback) {
console.log(`Parsed message:`, data);
// Add execution count recorder logic here
return callback(data);
}
/**
* Collapse message for sending.
*
* @param {string} key The key for collapsing.
* @param {Object} message The message object.
* @returns {string} The collapsed message.
*/
collapseMessage(key, message) {
// Implement message collapsing logic here
return JSON.stringify(message);
}
}The provided code appears to be a part of a Node.js module, possibly for a Jupyter kernel. It contains several functions related to handling messages between the kernel and the front-end.
The do_init function is called when the kernel is initialized. It performs the following steps:
setupSockets function to set up the sockets.bindSockets function.do_init function on the kernel's meta kernel.do_respond function to send an idle status message back to the front-end.The do_respond function sends a response message back to the front-end. It takes two parameters: kernel and message.
wireRespond function to send the response message to the correct socket.This function is not defined in the provided code, but it's likely related to handling incoming messages from the front-end.
The bindSockets function is used to bind the sockets to the kernel. It takes a sockets object as a parameter.
The wireRespond function sends a response message to the correct socket. It takes two parameters: kernel and message.
collapseMessage function.The wireMessage function is not implemented in the provided code, but it's likely related to handling incoming messages from the front-end.
There are several TODO comments in the code, indicating tasks that need to be completed:
wireMessage.The code uses the following functions:
setupSockets: Not defined in the provided code.bindSockets: Defined in the code.wireRespond: Defined in the code.wireMessage: Not implemented in the provided code.collapseMessage: Not defined in the provided code.do_init: Defined in the code.do_respond: Defined in the code.do_message: Not defined in the provided code.