feat(pool): ability to designate a new master

See vatesfr/xo-web#2213

src/api/pool.js

@@ -54,6 +54,25 @@ setDefaultSr.params = {
 setDefaultSr.resolve = {
   sr: ['sr', 'SR']
 }
+
+// -------------------------------------------------------------------
+
+export async function setPoolMaster ({ host }) {
+  await this.hasPermissions(this.user.id, [ [ host.$pool, 'administrate' ] ])
+
+  await this.getXapi(host).setPoolMaster(host._xapiId)
+}
+
+setPoolMaster.params = {
+  host: {
+    type: 'string'
+  }
+}
+
+setPoolMaster.resolve = {
+  host: ['host', 'host']
+}
+
 // -------------------------------------------------------------------
 
 export async function installPatch ({pool, patch: patchUuid}) {

src/xapi/index.js

@@ -350,6 +350,12 @@ export default class Xapi extends XapiBase {
 
   // =================================================================
 
+  async setPoolMaster (hostId) {
+    await this.call('pool.designate_new_master', this.getObject(hostId).$ref)
+  }
+
+  // =================================================================
+
   async joinPool (masterAddress, masterUsername, masterPassword, force = false) {
     await this.call(
       force ? 'pool.join_force' : 'pool.join',