From bfd4ccbeaa4d5e99ae535b4c3c7deb8004328de4 Mon Sep 17 00:00:00 2001
From: Erwan Miran <mirwan@users.noreply.github.com>
Date: Wed, 17 Oct 2018 00:32:26 +0200
Subject: [PATCH] Calico: Ability to define global peers (#3493)

---
 docs/calico.md                                |  7 +++
 roles/network_plugin/calico/tasks/install.yml | 48 +++++++++++++++++--
 2 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/docs/calico.md b/docs/calico.md
index e826ddc8b..d213f1f72 100644
--- a/docs/calico.md
+++ b/docs/calico.md
@@ -79,6 +79,13 @@ you'll need to edit the inventory and add a hostvar `local_as` by node.
 node1 ansible_ssh_host=95.54.0.12 local_as=xxxxxx
 ```
 
+##### Optional : Defining BGP peers
+
+Peers can be defined using the `peers` variable (see docs/calico_peer_example examples).
+In order to define global peers, the `peers` variable can be defined in group_vars with the "scope" attribute of each global peer set to "global".
+In order to define peers on a per node basis, the `peers` variable must be defined in hostvars.
+NB: Ansible's `hash_behaviour` is by default set to "replace", thus defining both global and per node peers would end up with having only per node peers. If having both global and per node peers defined was meant to happen, global peers would have to be defined in hostvars for each host (as well as per node peers)
+
 ##### Optional : Define global AS number
 
 Optional parameter `global_as_num` defines Calico global AS number (`/calico/bgp/v1/global/as_num` etcd key).
diff --git a/roles/network_plugin/calico/tasks/install.yml b/roles/network_plugin/calico/tasks/install.yml
index fc359366c..a76a0650d 100644
--- a/roles/network_plugin/calico/tasks/install.yml
+++ b/roles/network_plugin/calico/tasks/install.yml
@@ -205,7 +205,7 @@
     - local_as is defined
     - groups['calico-rr'] | default([]) | length == 0
 
-- name: Calico | Configure peering with router(s)
+- name: Calico | Configure peering with router(s) at node scope
   shell: >
    echo '{
    "apiVersion": "projectcalico.org/v3",
@@ -221,13 +221,13 @@
   retries: 4
   delay: "{{ retry_stagger | random + 3 }}"
   with_items:
-    - "{{ peers|default([]) }}"
+    - "{{ peers|rejectattr('scope','equalto', 'global')|default([]) }}"
   when:
     - calico_version | version_compare('v3.0.0', '>=')
     - peer_with_router|default(false)
     - inventory_hostname in groups['k8s-cluster']
 
-- name: Calico | Configure peering with router(s) (legacy)
+- name: Calico | Configure peering with router(s) at node scope (legacy)
   shell: >
    echo '{
    "kind": "bgpPeer",
@@ -238,7 +238,47 @@
    | {{ bin_dir }}/calicoctl create --skip-exists -f -
   retries: 4
   delay: "{{ retry_stagger | random + 3 }}"
-  with_items: "{{ peers|default([]) }}"
+  with_items: "{{ peers|rejectattr('scope','equalto', 'global')|default([]) }}"
+  when:
+    - calico_version | version_compare('v3.0.0', '<')
+    - peer_with_router|default(false)
+    - inventory_hostname in groups['k8s-cluster']
+
+- name: Calico | Configure peering with router(s) at global scope
+  shell: >
+   echo '{
+   "apiVersion": "projectcalico.org/v3",
+   "kind": "BGPPeer",
+   "metadata": {
+      "name": "global-{{ item.router_id }}"
+   },
+   "spec": {
+      "asNumber": "{{ item.as }}",
+      "peerIP": "{{ item.router_id }}"
+   }}' | {{ bin_dir }}/calicoctl create --skip-exists -f -
+  retries: 4
+  delay: "{{ retry_stagger | random + 3 }}"
+  with_items:
+    - "{{ peers|selectattr('scope','equalto', 'global')|default([]) }}"
+  run_once: true
+  when:
+    - calico_version | version_compare('v3.0.0', '>=')
+    - peer_with_router|default(false)
+    - inventory_hostname in groups['k8s-cluster']
+
+- name: Calico | Configure peering with router(s) at global scope (legacy)
+  shell: >
+   echo '{
+   "kind": "bgpPeer",
+   "spec": {"asNumber": "{{ item.as }}"},
+   "apiVersion": "v1",
+   "metadata": {"scope": "global", "peerIP": "{{ item.router_id }}"}
+   }'
+   | {{ bin_dir }}/calicoctl create --skip-exists -f -
+  retries: 4
+  delay: "{{ retry_stagger | random + 3 }}"
+  with_items: "{{ peers|selectattr('scope','equalto', 'global')|default([]) }}"
+  run_once: true
   when:
     - calico_version | version_compare('v3.0.0', '<')
     - peer_with_router|default(false)