--- /dev/null
+.. _grpc-dev:
+
+***************
+Northbound gRPC
+***************
+
+.. _grpc-languages-bindings:
+
+Programming Language Bindings
+=============================
+
+The gRPC supported programming language bindings can be found here:
+https://grpc.io/docs/languages/
+
+After picking a programming language that supports gRPC bindings, the
+next step is to generate the FRR northbound bindings. To generate the
+northbound bindings you'll need the programming language binding
+generator tools and those are language specific.
+
+Next sections will use Ruby as an example for writing scripts to use
+the northbound.
+
+
+.. _grpc-ruby-generate:
+
+Generating Ruby FRR Bindings
+----------------------------
+
+Generating FRR northbound bindings for Ruby example:
+
+::
+
+ # Install the required gems:
+ # - grpc: the gem that will talk with FRR's gRPC plugin.
+ # - grpc-tools: the gem that provides the code generator.
+ gem install grpc
+ gem install grpc-tools
+
+ # Create your project/scripts directory:
+ mkdir /tmp/frr-ruby
+
+ # Go to FRR's grpc directory:
+ cd grpc
+
+ # Generate the ruby bindings:
+ grpc_tools_ruby_protoc \
+ --ruby_out=/tmp/frr-ruby \
+ --grpc_out=/tmp/frr-ruby \
+ frr-northbound.proto
+
+
+.. _grpc-ruby-if-sample:
+
+Using Ruby To Get Interfaces State
+----------------------------------
+
+Here is a sample script to print all interfaces FRR discovered:
+
+::
+
+ require 'frr-northbound_services_pb'
+
+ # Create the connection with FRR's gRPC:
+ stub = Frr::Northbound::Stub.new('localhost:50051', :this_channel_is_insecure)
+
+ # Create a new state request to get interface state:
+ request = Frr::GetRequest.new
+ request.type = :STATE
+ request.path.push('/frr-interface:lib')
+
+ # Ask FRR.
+ response = stub.get(request)
+
+ # Print the response.
+ response.each do |result|
+ result.data.data.each_line do |line|
+ puts line
+ end
+ end
+
+
+.. note::
+
+ The generated files will assume that they are in the search path (e.g.
+ inside gem) so you'll need to either edit it to use ``require_relative`` or
+ tell Ruby where to look for them. For simplicity we'll use ``-I .`` to tell
+ it is in the current directory.
+
+
+The previous script will output something like this:
+
+::
+
+ $ cd /tmp/frr-ruby
+ # Add `-I.` so ruby finds the FRR generated file locally.
+ $ ruby -I. interface.rb
+ {
+ "frr-interface:lib": {
+ "interface": [
+ {
+ "name": "eth0",
+ "vrf": "default",
+ "state": {
+ "if-index": 2,
+ "mtu": 1500,
+ "mtu6": 1500,
+ "speed": 1000,
+ "metric": 0,
+ "phy-address": "11:22:33:44:55:66"
+ },
+ "frr-zebra:zebra": {
+ "state": {
+ "up-count": 0,
+ "down-count": 0
+ }
+ }
+ },
+ {
+ "name": "lo",
+ "vrf": "default",
+ "state": {
+ "if-index": 1,
+ "mtu": 0,
+ "mtu6": 65536,
+ "speed": 0,
+ "metric": 0,
+ "phy-address": "00:00:00:00:00:00"
+ },
+ "frr-zebra:zebra": {
+ "state": {
+ "up-count": 0,
+ "down-count": 0
+ }
+ }
+ }
+ ]
+ }
+ }
+
+
+.. _grpc-ruby-bfd-profile-sample:
+
+Using Ruby To Create BFD Profiles
+---------------------------------
+
+In this example you'll learn how to edit configuration using JSON
+and programmatic (XPath) format.
+
+::
+
+ require 'frr-northbound_services_pb'
+
+ # Create the connection with FRR's gRPC:
+ stub = Frr::Northbound::Stub.new('localhost:50051', :this_channel_is_insecure)
+
+ # Create a new candidate configuration change.
+ new_candidate = stub.create_candidate(Frr::CreateCandidateRequest.new)
+
+ # Use JSON to configure.
+ request = Frr::LoadToCandidateRequest.new
+ request.candidate_id = new_candidate.candidate_id
+ request.type = :MERGE
+ request.config = Frr::DataTree.new
+ request.config.encoding = :JSON
+ request.config.data = <<-EOJ
+ {
+ "frr-bfdd:bfdd": {
+ "bfd": {
+ "profile": [
+ {
+ "name": "test-prof",
+ "detection-multiplier": 4,
+ "required-receive-interval": 800000
+ }
+ ]
+ }
+ }
+ }
+ EOJ
+
+ # Load configuration to candidate.
+ stub.load_to_candidate(request)
+
+ # Commit candidate.
+ stub.commit(
+ Frr::CommitRequest.new(
+ candidate_id: new_candidate.candidate_id,
+ phase: :ALL,
+ comment: 'create test-prof'
+ )
+ )
+
+ #
+ # Now lets delete the previous profile and create a new one.
+ #
+
+ # Create a new candidate configuration change.
+ new_candidate = stub.create_candidate(Frr::CreateCandidateRequest.new)
+
+ # Edit the configuration candidate.
+ request = Frr::EditCandidateRequest.new
+ request.candidate_id = new_candidate.candidate_id
+
+ # Delete previously created profile.
+ request.delete.push(
+ Frr::PathValue.new(
+ path: "/frr-bfdd:bfdd/bfd/profile[name='test-prof']",
+ )
+ )
+
+ # Add new profile with two configurations.
+ request.update.push(
+ Frr::PathValue.new(
+ path: "/frr-bfdd:bfdd/bfd/profile[name='test-prof-2']/detection-multiplier",
+ value: 5.to_s
+ )
+ )
+ request.update.push(
+ Frr::PathValue.new(
+ path: "/frr-bfdd:bfdd/bfd/profile[name='test-prof-2']/desired-transmission-interval",
+ value: 900_000.to_s
+ )
+ )
+
+ # Modify the candidate.
+ stub.edit_candidate(request)
+
+ # Commit the candidate configuration.
+ stub.commit(
+ Frr::CommitRequest.new(
+ candidate_id: new_candidate.candidate_id,
+ phase: :ALL,
+ comment: 'replace test-prof with test-prof-2'
+ )
+ )
+
+
+And here is the new FRR configuration:
+
+::
+
+ $ sudo vtysh -c 'show running-config'
+ ...
+ bfd
+ profile test-prof-2
+ detect-multiplier 5
+ transmit-interval 900
+ !
+ !
--- /dev/null
+.. _grpc:
+
+***************
+Northbound gRPC
+***************
+
+.. program:: configure
+
+*gRPC* provides a combined front end to all FRR daemons using the YANG
+northbound. It is currently disabled by default due its experimental
+stage, but it can be enabled with :option:`--enable-grpc` option in the
+configure script.
+
+
+.. _grpc-features:
+
+Northbound gRPC Features
+========================
+
+* Get/set configuration using JSON/XML/XPath encondings.
+* Execute YANG RPC calls.
+* Lock/unlock configuration.
+* Create/edit/load/update/commit candidate configuration.
+* List/get transactions.
+
+
+.. note::
+
+ There is currently no support for YANG notifications.
+
+
+.. note::
+
+ You can find more information on how to code programs to interact
+ with FRR by reading the gRPC Programming Language Bindings section
+ in the `developer's documentation
+ <http://docs.frrouting.org/projects/dev-guide/en/latest/grpc.html>`_.
+
+
+.. _grpc-config:
+
+Daemon gRPC Configuration
+=========================
+
+The *gRPC* module accepts the following run time option:
+
+- ``port``: the port to listen to (defaults to ``50051``).
+
+
+.. note::
+
+ At the moment only localhost connections with no SSL/TLS are
+ supported.
+
+
+To configure FRR daemons to listen to gRPC you need to append the
+following parameter to the daemon's command line: ``-M grpc``
+(optionally ``-M grpc:PORT`` to specify listening port).
+
+To do that in production you need to edit the ``/etc/frr/daemons`` file
+so the daemons get started with the command line argument. Example:
+
+::
+
+ # other daemons...
+ bfdd_options=" --daemon -A 127.0.0.1 -M grpc"