The prometheus metrics refractoring (#8003)

The measures are consolidated to the following metrics

- `disk_storage_used` : Disk space used by the disk.
- `disk_storage_available`: Available disk space left on the disk.
- `disk_storage_total`: Total disk space on the disk.
- `disks_offline`: Total number of offline disks in current MinIO instance.
- `disks_total`: Total number of disks in current MinIO instance.
- `s3_requests_total`: Total number of s3 requests in current MinIO instance.
- `s3_errors_total`: Total number of errors in s3 requests in current MinIO instance.
- `s3_requests_current`: Total number of active s3 requests in current MinIO instance.
- `internode_rx_bytes_total`: Total number of internode bytes received by current MinIO server instance.
- `internode_tx_bytes_total`: Total number of bytes sent to the other nodes by current MinIO server instance.
- `s3_rx_bytes_total`: Total number of s3 bytes received by current MinIO server instance.
- `s3_tx_bytes_total`: Total number of s3 bytes sent by current MinIO server instance.
- `minio_version_info`: Current MinIO version with commit-id.
- `s3_ttfb_seconds_bucket`: Histogram that holds the latency information of the requests.

And this PR also modifies the current StorageInfo queries

- Decouples StorageInfo from ServerInfo .
- StorageInfo is enhanced to give endpoint information.

NOTE: ADMIN API VERSION IS BUMPED UP IN THIS PR

Fixes #7873

browser/app/js/browser/StorageInfo.js

@@ -26,6 +26,7 @@ export class StorageInfo extends React.Component {
   }
   render() {
     const { used } = this.props.storageInfo
+    var totalUsed = used.reduce((v1, v2) => v1 + v2, 0)
     return (
       <div className="feh-used">
         <div className="fehu-chart">
@@ -34,7 +35,7 @@ export class StorageInfo extends React.Component {
         <ul>
           <li>
             <span>Used: </span>
-            {humanize.filesize(used)}
+            {humanize.filesize(totalUsed)}
           </li>
         </ul>
       </div>
@@ -54,4 +55,7 @@ const mapDispatchToProps = dispatch => {
   }
 }
 
-export default connect(mapStateToProps, mapDispatchToProps)(StorageInfo)
+export default connect(
+  mapStateToProps,
+  mapDispatchToProps
+)(StorageInfo)

browser/app/js/browser/__tests__/StorageInfo.test.js

@@ -21,10 +21,7 @@ import { StorageInfo } from "../StorageInfo"
 describe("StorageInfo", () => {
   it("should render without crashing", () => {
     shallow(
-      <StorageInfo
-        storageInfo={{ used: 60 }}
-        fetchStorageInfo={jest.fn()}
-      />
+      <StorageInfo storageInfo={{ used: [60] }} fetchStorageInfo={jest.fn()} />
     )
   })
 
@@ -32,7 +29,7 @@ describe("StorageInfo", () => {
     const fetchStorageInfo = jest.fn()
     shallow(
       <StorageInfo
-        storageInfo={{ used: 60 }}
+        storageInfo={{ used: [60] }}
         fetchStorageInfo={fetchStorageInfo}
       />
     )

browser/app/js/browser/__tests__/actions.test.js

@@ -20,7 +20,7 @@ import * as actionsCommon from "../actions"
 
 jest.mock("../../web", () => ({
   StorageInfo: jest.fn(() => {
-    return Promise.resolve({ storageInfo: { Used: 60 } })
+    return Promise.resolve({ storageInfo: { Used: [60] } })
   }),
   ServerInfo: jest.fn(() => {
     return Promise.resolve({
@@ -40,7 +40,7 @@ describe("Common actions", () => {
   it("creates common/SET_STORAGE_INFO after fetching the storage details ", () => {
     const store = mockStore()
     const expectedActions = [
-      { type: "common/SET_STORAGE_INFO", storageInfo: { used: 60 } }
+      { type: "common/SET_STORAGE_INFO", storageInfo: { used: [60] } }
     ]
     return store.dispatch(actionsCommon.fetchStorageInfo()).then(() => {
       const actions = store.getActions()

browser/app/js/browser/__tests__/reducer.test.js

@@ -22,8 +22,9 @@ describe("common reducer", () => {
     expect(reducer(undefined, {})).toEqual({
       sidebarOpen: false,
       storageInfo: {
-        total: 0,
-        free: 0
+        total: [0],
+        free: [0],
+        used: [0]
       },
       serverInfo: {}
     })
@@ -61,11 +62,11 @@ describe("common reducer", () => {
         {},
         {
           type: actionsCommon.SET_STORAGE_INFO,
-          storageInfo: { total: 100, free: 40 }
+          storageInfo: { total: [100], free: [40] }
         }
       )
     ).toEqual({
-      storageInfo: { total: 100, free: 40 }
+      storageInfo: { total: [100], free: [40] }
     })
   })
 

browser/app/js/browser/reducer.js

@@ -19,7 +19,7 @@ import * as actionsCommon from "./actions"
 export default (
   state = {
     sidebarOpen: false,
-    storageInfo: { total: 0, free: 0 },
+    storageInfo: { total: [0], free: [0], used: [0] },
     serverInfo: {}
   },
   action