darkfi/doc/src/learn/dchat/network-tools/get-info.md

get_info

If you run Alice now, you'll see the following output:

[DEBUG] jsonrpc-server: Trying to bind listener on tcp://127.0.0.1:55054

That indicates that our JSON-RPC server is up and running. However, there's currently no client for us to connect to. That's where dnetview comes in. dnetview implements a JSON-RPC client that calls a single method: get_info().

To use it, let's return to our JsonRpcInterface and add the following method:

{{#include ../../../../../example/dchat/src/rpc.rs:45:52}}

And add it to handle_request():

{{#include ../../../../../example/dchat/src/rpc.rs:21}}
        //...
{{#include ../../../../../example/dchat/src/rpc.rs:28:34}}

This calls the p2p function get_info() and passes the returned data into a JsonResponse.

Under the hood, this function triggers a hierarchy of get_info() calls which deliver info specific to a node, its inbound or outbound Session's, and the Channel's those Session's run.

Here's what happens:

{{#include ../../../../../src/net/p2p.rs:111:126}}

Here we return two pieces of info that are unique to a node: external_addr and state. We couple that data with SessionInfo by calling get_info() on each Session.

Session::get_info() returns data related to a Session (for example, an Inbound accept_addr in the case of an inbound Session). Session::get_info() then calls the function Channel::get_info() which returns data specific to a Channel. This happens via a child struct called ChannelInfo.

This is ChannelInfo::get_info().

{{#include ../../../../../src/net/channel.rs:48:58}}

dnetview uses the info returned from Channel and Session and node-specific info like external_addr to display an overview of the p2p network.