# `Monitorex.Cluster`

Cluster support for Monitorex — provides multi-node data aggregation
across distributed Erlang nodes.

Use `fetch_from_all_nodes/2` to query all nodes in the cluster, then
pass the results to the appropriate `merge_*` function to produce
consolidated aggregates.

# `connected_nodes`

```elixir
@spec connected_nodes() :: [node()]
```

Returns all reachable nodes including `Node.self()`.

When `cluster_mode` config is `:single`, returns only `[Node.self()]`.
Otherwise returns `[Node.self() | Node.list()]`.

# `fetch_from_all_nodes`

```elixir
@spec fetch_from_all_nodes(atom(), list()) :: [{node(), term()}]
```

Calls the given `Storage` function on **all** connected nodes via RPC.

Returns a list of `{node, result}` tuples for successful calls.
Nodes that return `{:badrpc, _}` are silently omitted.

## Parameters

  * `func_name` — atom name of a function on `Monitorex.Storage`
    (e.g. `:list_hosts`, `:list_routes`, `:list_recent_outbound`)
  * `args` — list of arguments to pass to the function

## Configuration

  * `:cluster_max_concurrency` — max concurrent RPC calls (default `3`)
  * `:cluster_rpc_timeout` — per-call timeout in ms (default `5_000`)

# `merge_consumers`

```elixir
@spec merge_consumers([{node(), [map()]}]) :: [map()]
```

Merges consumer aggregates from multiple nodes.

Same merge strategy as `merge_hosts/1` but for consumer data.

# `merge_endpoints`

```elixir
@spec merge_endpoints([{node(), [map()]}]) :: [map()]
```

Merges endpoint aggregates from multiple nodes.

Same merge strategy as `merge_hosts/1` but for endpoint data.

# `merge_hosts`

```elixir
@spec merge_hosts([{node(), [map()]}]) :: [map()]
```

Merges host aggregates collected from multiple nodes.

## Input

A list of `{node, [host_map]}` tuples — as returned by
`fetch_from_all_nodes(:list_hosts, [])`.

## Merge strategy

  * `requests`, `errors`, `total_duration` are summed
  * `avg_latency` is recomputed as `total_duration / requests`
  * `p50`, `p95`, `p99` are weighted by each node's request count
  * `:node` is set to a list of all source nodes that contributed

# `merge_recent`

```elixir
@spec merge_recent([{node(), [map()]}], pos_integer()) :: [map()]
```

Merges recent event lists from multiple nodes.

## Input

A list of `{node, [event_struct]}` tuples.

## Merge strategy

  * All events are flattened into a single list
  * Each event is tagged with its source `:node`
  * Sorted by `timestamp` descending
  * Returns the top `top_n` events (default `50`)

# `merge_routes`

```elixir
@spec merge_routes([{node(), [map()]}]) :: [map()]
```

Merges route aggregates from multiple nodes.

Same merge strategy as `merge_hosts/1` but for route data.

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*Consult [api-reference.md](api-reference.md) for complete listing*