Reimplement Monitor view as React functional component with hooks

[yurishkuro]

packages/jaeger-ui/src/components/Monitor/ServicesView/index.tsx is a class based component with pretty convoluted state management. It can be simplified if implemented as a functional component with hooks.

References:

• https://www.jaegertracing.io/docs/1.51/spm/
• https://github.com/jaegertracing/jaeger/tree/main/docker-compose/monitor#http-api

Related/similar PRs:

• replace match.params with useParams hook #1837

[takuabonn]

hi @yurishkuro
I want to work in this issue. will u assign it to me?

[yurishkuro]

Go ahead

[Sweetdevil144]

So, we're gonna flip the MonitorATMServicesViewImpl class to a functional component. Here's the game plan of how I would proceed with this issue:

1. State with useState: For each state variable in your class component, we'll switch to using useState. It's pretty straightforward. Like, if you have a state variable graphWidth in your class, it turns into:

   const [graphWidth, setGraphWidth] = useState(300);

   Repeat this for each piece of state (serviceOpsMetrics, searchOps, etc.).

2. Lifecycle Methods with useEffect: Your componentDidMount, componentDidUpdate, and componentWillUnmount all get replaced by useEffect. Here's an example that covers component mounting and unmounting logic:

   useEffect(() => {
       fetchServices(); // Replace with your actual data fetching or setup code
       // Any additional setup code goes here
   
       return () => {
           // This is your cleanup code, like componentWillUnmount
           // e.g., remove event listeners
       };
   }, []); // The empty array makes it run only once on mount and unmount

3. Refactor Methods to Functions: Convert class methods into functions. For instance, if you have a method for updating dimensions in your class, it would be something like:

   const updateDimensions = () => {
       // Your logic to update dimensions
   };

4. Handling Redux: If you're using Redux, you'll use useSelector for selecting state and useDispatch for dispatching actions. Like this:

   const services = useSelector(state => state.services);
   const dispatch = useDispatch();
   
   // When you need to dispatch an action
   const fetchMetrics = () => {
       dispatch(fetchMetricsAction());
   };

5. Testing: After refactoring, test to ensure all functionalities work as expected. Check if state updates correctly, effects run as intended, and the component behaves as it did before.

The goal is to keep the logic intact but just translate it into the functional component style. Hope this helps you envision how the refactored component will look! Let me know if there's a specific part you want more detail on.

[EshaanAgg]

Hi! Is this issue available to work on?

[yurishkuro]

@EshaanAgg yes, since there is no PR attached

[RISHIKESHk07]

@yurishkuro how to check if my code is running correct after changing the component

[RISHIKESHk07]

@yurishkuro i did rewrite the monitor , i don 't see any error except for the below , is there anything i missed
'''
7:56:27 PM [vite] http proxy error at /api/services:
Error: connect ECONNREFUSED 127.0.0.1:16686
at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1595:16) (x2)
'''

[yurishkuro]

why would making Reach changes result in any network-related errors?