Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/inputs/p4runtime/README.md

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+# P4 Runtime Input Plugin
+
+P4 is a language for programming the data plane of network devices,
+such as Programmable Switches or Programmable Network Interface Cards.
+The P4Runtime API is a control plane specification to manage
+the data plane elements of those devices dynamically by a P4 program.
+
+The `p4runtime` plugin gathers metrics about `Counter` values
+present in P4 Program loaded onto networking device.
+Metrics are collected through gRPC connection with
+[P4Runtime](https://github.com/p4lang/p4runtime) server.
+
+P4Runtime Plugin uses `PkgInfo.Name` field.
+If user wants to gather information about program name, please follow
+[6.2.1. Annotating P4 code with PkgInfo] instruction and apply changes
+to your P4 program.
+
+## Global configuration options <!-- @/docs/includes/plugin_config.md -->
+
+In addition to the plugin-specific configuration settings, plugins support
+additional global and plugin configuration settings. These settings are used to
+modify metrics, tags, and field or create aliases and configure ordering, etc.
+See the [CONFIGURATION.md][CONFIGURATION.md] for more details.
+
+[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins
+
+## Configuration
+
+```toml @sample.conf
+# P4Runtime telemetry input plugin
+[[inputs.p4runtime]]
+  ## Define the endpoint of P4Runtime gRPC server to collect metrics.
+  # endpoint = "127.0.0.1:9559"
+  ## Set DeviceID required for Client Arbitration.
+  ## https://p4.org/p4-spec/p4runtime/main/P4Runtime-Spec.html#sec-client-arbitration-and-controller-replication
+  # device_id = 1
+  ## Filter counters by their names that should be observed.
+  ## Example: counter_names_include=["ingressCounter", "egressCounter"]
+  # counter_names_include = []
+
+  ## Optional TLS Config.
+  ## Enable client-side TLS and define CA to authenticate the device.
+  # enable_tls = false
+  # tls_ca = "/etc/telegraf/ca.crt"
+  ## Set minimal TLS version to accept by the client.
+  # tls_min_version = "TLS12"
+  ## Use TLS but skip chain & host verification.
+  # insecure_skip_verify = true
+
+  ## Define client-side TLS certificate & key to authenticate to the device.
+  # tls_cert = "/etc/telegraf/client.crt"
+  # tls_key = "/etc/telegraf/client.key"
+```
+
+## Metrics
+
+P4Runtime gRPC server communicates using [p4runtime.proto] Protocol Buffer.
+Static information about P4 program loaded into programmable switch
+are collected by `GetForwardingPipelineConfigRequest` message.
+Plugin gathers dynamic metrics with `Read` method.
+`Readrequest` is defined with single `Entity` of type `CounterEntry`.
+Since P4 Counter is array, plugin collects values of every cell of array
+by [wildcard query].
+
+Counters defined in P4 Program have unique ID and name.
+Counters are arrays, thus `counter_index` informs
+which cell value of array is described in metric.
+
+Tags are constructed in given manner:
+
+- `p4program_name`: P4 program name provided by user.
+If user wants to gather information about program name, please follow
+[6.2.1. Annotating P4 code with PkgInfo] instruction and apply changes
+to your P4 program.
+- `counter_name`: Name of given counter in P4 program.
+- `counter_type`: Type of counter (BYTES, PACKETS, BOTH).
+
+Fields are constructed in given manner:
+
+- `bytes`: Number of bytes gathered in counter.
+- `packets` Number of packets gathered in counter.
+- `counter_index`: Index at which metrics are collected in P4 counter.
+
+## Example Output
+
+Expected output for p4runtime plugin instance
+running on host named `p4runtime-host`:
+
+```text
+p4_runtime,counter_name=MyIngress.egressTunnelCounter,counter_type=BOTH,host=p4 bytes=408i,packets=4i,counter_index=200i 1675175030000000000
+```
+
+[6.2.1. Annotating P4 code with PkgInfo]: https://p4.org/p4-spec/p4runtime/main/P4Runtime-Spec.html#sec-annotating-p4-code-with-pkginfo
+[p4runtime.proto]: https://github.com/p4lang/p4runtime/blob/main/proto/p4/v1/p4runtime.proto
+[wildcard query]: https://github.com/p4lang/p4runtime/blob/main/proto/p4/v1/p4runtime.proto#L379