Service for rTorrent. (#511)

Service for rTorrent.

docs/customservices.md

@@ -25,6 +25,7 @@ within Homer:
   - [Mealie](#mealie)
   - [Healthchecks](#healthchecks)
   - [Proxmox](#proxmox)
+  - [rTorrent](#rtorrent)
   - [qBittorrent](#qbittorrent)
 
 If you experiencing any issue, please have a look to the [troubleshooting](troubleshooting.md) page.
@@ -249,6 +250,27 @@ Two lines are needed in the config.yml :
 The url must be the root url of the Healthchecks application.
 The Healthchecks API key can be found in Settings > API Access > API key (read-only). The key is needed to access Healthchecks API.
 
+## rTorrent
+
+This service displays the global upload and download rates, as well as the number of torrents
+listed in rTorrent. The service communicates with the rTorrent XML-RPC interface which needs
+to be accessible from the browser. Please consult
+[the instructions](https://github.com/rakshasa/rtorrent-doc/blob/master/RPC-Setup-XMLRPC.md)
+for setting up rTorrent and make sure the correct CORS-settings are applied. Examples for various
+servers can be found at https://enable-cors.org/server.html.
+
+```yaml
+- name: "rTorrent"
+  logo: "assets/tools/sample.png"
+  url: "http://192.168.0.151" # Your rTorrent web UI, f.e. ruTorrent or Flood.
+  xmlrpc: "http://192.168.0.151:8081" # Reverse proxy for rTorrent's XML-RPC.
+  type: "Rtorrent"
+  rateInterval: 5000 # Interval for updating the download and upload rates.
+  torrentInterval: 60000 # Interval for updating the torrent count.
+  username: "username" # Username for logging into rTorrent (if applicable).
+  password: "password" # Password for logging into rTorrent (if applicable).
+
+
 ## Proxmox
 
 This service displays status information of a Proxmox node (VMs running and disk, memory and cpu used). It uses the proxmox API and [API Tokens](https://pve.proxmox.com/pve-docs/pveum-plain.html) for authorization so you need to generate one to set in the yaml config. You can set it up in Proxmox under Permissions > API Tokens. You also need to know the realm the user of the API Token is assigned to (by default pam).

dummy-data/rtorrent/download_list

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<methodResponse>
+<params>
+<param><value><array><data>
+<value><string>2BAC78C9E10D82415142E57D24601F2FD8927816</string></value>
+<value><string>8BB10DB9EA239106D4907601C342ABBA29BE4391</string></value>
+<value><string>2790CE71493BE7083929D5A1CE9CFD6B8394F224</string></value>
+</data></array></value></param>
+</params>
+</methodResponse>

dummy-data/rtorrent/global_down

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<methodResponse>
+<params>
+<param><value><i8>149279</i8></value></param>
+</params>
+</methodResponse>

dummy-data/rtorrent/global_up

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<methodResponse>
+<params>
+<param><value><i8>45616</i8></value></param>
+</params>
+</methodResponse>

src/components/services/Rtorrent.vue

@@ -0,0 +1,153 @@
+<template>
+  <Generic :item="item">
+    <template #content>
+      <p class="title is-4">{{ item.name }}</p>
+      <p class="subtitle is-6">
+        <span v-if="error" class="error">An error has occurred.</span>
+        <template v-else>
+          <span class="down">
+            <i class="fas fa-download"></i> {{ downRate }}
+          </span>
+          <span class="up">
+            <i class="fas fa-upload"></i> {{ upRate }}
+            </span>
+        </template>
+      </p>
+    </template>
+    <template #indicator>
+      <span v-if="!error" class="count">{{ count }}
+        <template v-if="count === 1">torrent</template>
+        <template v-else>torrents</template>
+      </span>
+    </template>
+  </Generic>
+</template>
+
+<script>
+import Generic from './Generic.vue';
+
+// Units to add to download and upload rates.
+const units = ['B', 'kiB', 'MiB', 'GiB'];
+
+// Take the rate in bytes and keep dividing it by 1k until the lowest
+// value for which we have a unit is determined. Return the value with
+// up to two decimals as a string and unit/s appended.
+const displayRate = (rate) => {
+  let i = 0;
+  
+  while (rate > 1000 && i < units.length) {
+    rate /= 1000;
+    i++;
+  }
+
+  return Intl.NumberFormat(undefined, {maximumFractionDigits: 2})
+    .format(rate || 0) + ` ${units[i]}/s`;
+}
+
+export default {
+  name: 'rTorrent',
+  props: {item: Object},
+  components: {Generic},
+  // Properties for download, upload, torrent count and errors.
+  data: () => ({dl: null, ul: null, count: null, error: null}),
+  // Computed properties for the rate labels.
+  computed: {
+    downRate: function() {
+      return displayRate(this.dl);
+    },
+    upRate: function() {
+      return displayRate(this.ul);
+    },
+  },
+  created() {
+    // Set intervals if configured so the rates and/or torrent count
+    // will be updated.
+    const rateInterval = parseInt(this.item.rateInterval, 10) || 0;
+    const torrentInterval = parseInt(this.item.torrentInterval, 10) || 0;
+
+    if (rateInterval > 0) {
+      setInterval(() => this.fetchRates(), rateInterval);
+    }
+
+    if (torrentInterval > 0) {
+      setInterval(() => this.fetchCount(), torrentInterval);
+    }
+    
+    // Fetch the initial values.
+    this.fetchRates();
+    this.fetchCount();
+  },
+  methods: {
+    // Perform two calls to the XML-RPC service and fetch download
+    // and upload rates. Values are saved to the `ul` and `dl`
+    // properties.
+    fetchRates: async function() {
+      this.getRate('throttle.global_up.rate')
+        .then((ul) => this.ul = ul)
+        .catch(() => this.error = true);
+
+      this.getRate('throttle.global_down.rate')
+        .then((dl) => this.dl = dl)
+        .catch(() => this.error = true);
+    },
+    // Perform a call to the XML-RPC service to fetch the number of
+    // torrents.
+    fetchCount: async function() {
+      this.getCount().catch(() => this.error = true);
+    },
+    // Fetch a numeric value from the XML-RPC service by requesting
+    // the specified method name and parsing the XML. The response
+    // is expected to adhere to the structure of a single numeric
+    // value.
+    getRate: async function(methodName) {
+      return this.getXml(methodName)
+        .then((xml) => parseInt(xml.getElementsByTagName('value')[0].firstChild.textContent, 10));
+    },
+    // Fetch the numer of torrents by requesting the download list
+    // and counting the number of entries therein.
+    getCount: async function() {
+      return this.getXml('download_list')
+        .then((xml) => {
+          const arrayEl = xml.getElementsByTagName('array');
+          this.count = arrayEl ? arrayEl[0].getElementsByTagName('value').length : 0;
+        });
+    },
+    // Perform a call to the XML-RPC service and parse the response
+    // as XML, which is then returned.
+    getXml: async function(methodName) {
+      const headers = {'Content-Type': 'text/xml'};
+
+      if (this.item.username && this.item.password) {
+        headers['Authorization'] = `${this.item.username}:${this.item.password}`;
+      }
+
+      return fetch(`${this.item.xmlrpc.replace(/\/$/, '')}/RPC2`, {
+        method: 'POST',
+        headers,
+        body: `<methodCall><methodName>${methodName}</methodName></methodCall>`
+      })
+      .then((response) => {
+        if (!response.ok) {
+          throw Error(response.statusText);
+        }
+
+        return response.text();
+      })
+      .then((text) => Promise.resolve(new DOMParser().parseFromString(text, 'text/xml')));
+    }
+  }
+}
+</script>
+
+<style scoped lang="scss">
+.error {
+  color: #e51111 !important;
+}
+.down {
+  margin-right: 1em;
+}
+.count {
+  color: var(--text);
+  font-size: 0.8em;
+}
+</style>