feat(api): change volume mount for networking to a simpler one

makes the old volume mount invalid and needs a new one to make the networking graph work correctly
again

BREAKING CHANGE: volume mount for networking graph is different now
close #58

README.md

@@ -60,7 +60,7 @@ To read more about configuration options, you can visit [the configuration secti
 docker container run -it \
   -p 80:3001 \
   -v /etc/os-release:/etc/os-release:ro \
-  --mount type=bind,source=$(readlink -f /sys/class/net/$(ip addr show | awk '/inet.*brd/{print $NF; exit}')),destination=/mnt/eth0 \
+  -v /proc/1/ns/net:/mnt/host_ns_net:ro \
   --privileged \
   mauricenino/dashdot
 ```
@@ -69,19 +69,18 @@ docker container run -it \
 
 <!-- -->
 
-> Note: The `--mount` flag is needed to correctly determine the network info.
-> If the source part does not correctly resolve for you, you can manually get the
-> path by executing `readlink -f /sys/class/net/DEFAULT_INTERFACE`, where the default
-> interface is mostly named "eth0". If you don't want to use this flag, you can instead
-> use `--network host`, but then you will not be able to use custom docker networking
-> any more.
+> Note: The volume mount on `/proc/1/ns/net:/host_ns_net:ro` is needed to
+> correctly determine the network info. If you are not able to use this mount,
+> you will need to fall back to `--net host`, or you will only get the network
+> stats of the container instead of the host.
 
 <!-- -->
 
 > Note: The volume mount on `/etc/os-release:/etc/os-release:ro` is for the
 > dashboard to show the OS version of the host instead of the OS of the docker
 > container (which is running on Alpine Linux). If you wish to show the docker
-> container OS instead, just remove this line.
+> container OS instead, just remove this line. If you are not able to use this
+> mount, you can pass a custom OS with the `DASHDOT_OVERRIDE_OS` flag.
 
 ### Docker-Compose
 
@@ -104,16 +103,7 @@ services:
       - '80:3001'
     volumes:
       - /etc/os-release:/etc/os-release:ro
-      - type: bind
-        source: ${DEFAULT_INTERFACE_PATH}
-        target: /mnt/eth0
-```
-
-After setting up your `docker-compose.yml` file, you have to run the following
-command to start the dashboard:
-
-```bash
-DEFAULT_INTERFACE_PATH=$(readlink -f /sys/class/net/$(ip addr show | awk '/inet.*brd/{print $NF; exit}')) docker-compose up
+      - /proc/1/ns/net:/mnt/host_ns_net:ro
 ```
 
 ### Git

apps/api/src/dynamic-info.ts

@@ -1,10 +1,10 @@
 import { CpuLoad, NetworkLoad, RamLoad, StorageLoad } from '@dash/common';
 import { exec as cexec } from 'child_process';
-import * as fs from 'fs';
 import { interval, mergeMap, Observable, ReplaySubject } from 'rxjs';
 import * as si from 'systeminformation';
 import { inspect, promisify } from 'util';
 import { CONFIG } from './config';
+import { NET_INTERFACE } from './setup-networking';
 import { getStaticServerInfo } from './static-info';
 
 const exec = promisify(cexec);
@@ -91,9 +91,10 @@ export const netowrkObs = createBufferedInterval(
   CONFIG.network_shown_datapoints,
   CONFIG.network_poll_interval,
   async (): Promise<NetworkLoad> => {
-    if (fs.existsSync('/mnt/eth0/')) {
+    if (NET_INTERFACE !== 'unknown') {
       const { stdout } = await exec(
-        `cat /mnt/eth0/statistics/rx_bytes;cat /mnt/eth0/statistics/tx_bytes;`
+        `cat /mnt/host_sys/class/net/${NET_INTERFACE}/statistics/rx_bytes;` +
+          `cat /mnt/host_sys/class/net/${NET_INTERFACE}/statistics/tx_bytes;`
       );
       const [rx, tx] = stdout.split('\n').map(Number);
 

apps/api/src/index.ts

@@ -8,6 +8,7 @@ import { inspect } from 'util';
 import { CONFIG } from './config';
 import { cpuObs, netowrkObs, ramObs, storageObs } from './dynamic-info';
 import { environment } from './environments/environment';
+import { setupNetworking } from './setup-networking';
 import { getStaticServerInfo, runSpeedTest } from './static-info';
 
 const app = express();
@@ -32,9 +33,6 @@ if (environment.production) {
 app.get('/system-info', async (_, res) => {
   res.send(await getStaticServerInfo());
 });
-app.get('/ping', async (_, res) => {
-  res.send('pong');
-});
 
 // Send current system status
 io.on('connection', socket => {
@@ -75,6 +73,8 @@ server.listen(CONFIG.port, async () => {
     })
   );
 
+  await setupNetworking();
+
   console.log('Running speed-test (this may take a few minutes)...');
   try {
     console.log(

apps/api/src/setup-networking.ts

@@ -0,0 +1,33 @@
+import { exec as exaca } from 'child_process';
+import * as fs from 'fs';
+import { promisify } from 'util';
+
+const exec = promisify(exaca);
+
+export let NET_INTERFACE = 'unknown';
+
+export const setupNetworking = async () => {
+  if (fs.existsSync('/mnt/host_ns_net')) {
+    try {
+      await exec('mkdir -p /mnt/host_sys');
+      await exec(
+        'mountpoint -q /mnt/host_sys || nsenter --net=/mnt/host_ns_net mount -t sysfs nodevice /mnt/host_sys'
+      );
+    } catch (e) {
+      console.warn(e);
+    }
+
+    try {
+      const { stdout } = await exec(
+        "nsenter --net=/mnt/host_ns_net route | grep default | awk '{print $8}'"
+      );
+      NET_INTERFACE = stdout.trim();
+
+      console.log(`Using network interface "${NET_INTERFACE}"`);
+    } catch (e) {
+      console.warn(e);
+    }
+  } else {
+    console.log(`Using default container network interface`);
+  }
+};

docker-compose.yml

@@ -22,6 +22,4 @@ services:
     volumes:
       - ./:/app
       - /etc/os-release:/etc/os-release:ro
-      - type: bind
-        source: ${DEFAULT_INTERFACE_PATH}
-        target: /mnt/eth0
+      - /proc/1/ns/net:/mnt/host_ns_net:ro

package.json

@@ -21,8 +21,7 @@
     "start": "node .",
     "build": "nx run-many --target=build --configuration=production --all=true --parallel=true",
     "serve": "nx run-many --target=serve --all=true --parallel=true",
-    "start-dev": "docker-compose -p dashdot_dev -f ./docker-compose.yml up --remove-orphans",
-    "dev": "DEFAULT_INTERFACE_PATH=$(readlink -f /sys/class/net/$(ip addr show | awk '/inet.*brd/{print $NF; exit}')) yarn run start-dev",
+    "dev": "docker-compose -p dashdot_dev -f ./docker-compose.yml up --remove-orphans",
     "test": "nx run-many --target=test --all=true --parallel=true",
     "postinstall": "husky install",
     "commit": "git-cz"