Implement chart rendering

resources/js/main.js

@@ -51,6 +51,7 @@ async function startup() {
 
             let row_device = document.createElement('tr');
 
+            // create device name column
             let device_name_entry = document.createElement('td');
             let device_name = document.createElement('input');
             device_name.value = device_descriptor;
@@ -73,6 +74,7 @@ async function startup() {
             device_name_entry.appendChild(device_name_edit);
             row_device.appendChild(device_name_entry);
 
+            // get plug status
             const device_status_response = await fetch(
                 "/plug_state/" + device_id,
                 {
@@ -82,6 +84,7 @@ async function startup() {
 
             let device_state = JSON.parse(await device_status_response.json());
 
+            // create device led state column
             let device_led_state_entry = document.createElement('td');
             let device_led_state = document.createElement('label');
             device_led_state.innerText = device_state["led"];
@@ -98,6 +101,7 @@ async function startup() {
             device_led_state_entry.appendChild(device_led_off);
             row_device.appendChild(device_led_state_entry);
 
+            // create device power state column
             let device_power_state_entry = document.createElement('td');
             let device_power_state = document.createElement('label');
             device_power_state.innerText = device_state["power"];
@@ -114,11 +118,18 @@ async function startup() {
             device_power_state_entry.appendChild(device_power_off);
             row_device.appendChild(device_power_state_entry);
 
+            // create device power draw column
             let device_power_draw_entry = document.createElement('td');
-            let device_power_draw_ = document.createElement('label');
+            let device_power_draw = document.createElement('label');
-            device_power_draw_.innerText = device_state["power_draw"] + " W";
+            device_power_draw.innerText = device_state["power_draw"] + " W";
+            let device_power_draw_graph_button = document.createElement('button');
+            device_power_draw_graph_button.onclick = async () => { await render_graph(device_id) };
+            let device_power_draw_graph_button_icon = document.createElement('i');
+            device_power_draw_graph_button_icon.className = "fa fa-chart-bar";
 
-            device_power_draw_entry.appendChild(device_power_draw_);
+            device_power_draw_graph_button.appendChild(device_power_draw_graph_button_icon);
+            device_power_draw_entry.appendChild(device_power_draw);
+            device_power_draw_entry.appendChild(device_power_draw_graph_button);
             row_device.appendChild(device_power_draw_entry);
 
             table.appendChild(row_device);
@@ -163,7 +174,7 @@ async function power_on(plug) {
 }
 
 async function power_off(plug) {
-    await change_plug_state(plug, "pwoer", "off")
+    await change_plug_state(plug, "power", "off")
 }
 
 async function change_device_name(plug, name) {
@@ -178,3 +189,54 @@ async function change_device_name(plug, name) {
         console.error(response.body);
     }
 }
+
+async function render_graph(plug) {
+    // remove old graph, if present
+    let old = document.getElementById("chart");
+
+    if (old !== null) {
+        old.remove();
+    }
+
+    // create new chart div
+    let chart = document.createElement('canvas');
+    chart.id = "chart";
+
+    const response = await fetch(
+        "/plug_data/" + plug,
+        {
+            method: "GET"
+        }
+    );
+
+    const j = await response.json();
+    const data = JSON.parse(j);
+
+    let y = [];
+    let x = [];
+
+    for (let i = 0; i < data.length; i++) {
+        let [time, watts] = data[i];
+
+        x.push(time);
+        y.push(watts);
+    }
+
+    const chart_data = {
+        labels: x,
+        datasets: [{
+            label: plug,
+            data: y,
+            fill: false,
+            borderColor: 'rgb(75, 192, 192)',
+            tension: 0.1
+        }]
+    };
+
+    new Chart(chart, {
+        type: 'line',
+        data: chart_data,
+    });
+
+    document.getElementById("chart_div").appendChild(chart);
+}

resources/static/index.html

@@ -9,6 +9,8 @@
 
 <body>
     <div id="main"></div>
+    <div id="chart_div"></div>
+    <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
     <script type="text/javascript" src="/js/main.js"></script>
 </body>
 

src/db.rs

@@ -153,9 +153,11 @@ impl DataBase {
         self.sql
             .prepare(&format!(
                 "
-                    SELECT time, watts
+                    SELECT data.time, data.watts
                     FROM data
-                    WHERE device=\"{device}\"
+                    INNER JOIN devices
+                        ON data.device_id=devices.id
+                    WHERE devices.device=\"{device}\"
                 "
             ))?
             .query_map([], |row| Ok((row.get(0)?, row.get(1)?)))?

src/devices.rs

@@ -14,10 +14,6 @@ impl Devices {
         Ok(from_str(&fs::read_to_string(file)?)?)
     }
 
-    pub fn to_json(&self) -> Result<String> {
-        Ok(to_string(self)?)
-    }
-
     #[allow(unused)]
     pub fn save(&self, file: &str) -> Result<()> {
         fs::write(file, to_string_pretty(self)?)?;

src/main.rs

@@ -18,7 +18,9 @@ use anyhow::Result;
 use devices::Devices;
 use futures::{future::try_join_all, try_join, Future};
 use tasmota::Tasmota;
-use web_server::{change_device_name, change_plug_state, device_query, index, plug_state};
+use web_server::{
+    change_device_name, change_plug_state, device_query, index, plug_data, plug_state,
+};
 
 fn since_epoch() -> Result<u64> {
     Ok(SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs())
@@ -64,6 +66,7 @@ async fn run_web_server(
             .service(plug_state)
             .service(change_plug_state)
             .service(change_device_name)
+            .service(plug_data)
     })
     .bind(("0.0.0.0", 8062))
     .map_err(|err| anyhow::Error::msg(format!("failed binding to address: {err:#?}")))?

src/web_server.rs

@@ -2,7 +2,7 @@ use actix_files::NamedFile;
 use actix_web::{
     get, post,
     web::{Data, Json, Path},
-    Responder, ResponseError,
+    Error, Responder, ResponseError,
 };
 use serde::Serialize;
 use serde_json::to_string;
@@ -151,6 +151,22 @@ async fn change_plug_state(
     })
 }
 
+#[get("/plug_data/{plug}")]
+async fn plug_data(
+    param: Path<String>,
+    db: Data<Arc<Mutex<DataBase>>>,
+) -> Result<impl Responder, Error> {
+    let plug = param.into_inner();
+
+    let data = db
+        .lock()
+        .unwrap()
+        .read(&plug)
+        .map_err(|err| MyError::from(err))?;
+
+    Ok(Json(to_string(&data)?))
+}
+
 #[cfg(test)]
 mod test {
     use actix_web::{http::header::ContentType, test, App};