feat(data_generator): Build your own data based on the last state and…

… attributes of your entity (#14)

Fixes #6

.devcontainer/ui-lovelace.yaml

@@ -182,3 +182,15 @@ views:
             group_by:
               func: avg
               fill: 'null'
+
+      - type: custom:apexcharts-card
+        span:
+          start: day
+        series:
+          - entity: sensor.pvpc
+            data_generator: |
+              return [...Array(22).keys()].map((hour) => {
+                const attr = 'price_' + `${hour}`.padStart(2, '0') + 'h';
+                const value = entity.attributes[attr];
+                return [moment().startOf('day').hours(hour).valueOf(), value];
+              })

README.md

@@ -26,6 +26,7 @@ However, some things might be broken :grin:
   - [`group_by` Options](#group_by-options)
   - [`func` Options](#func-options)
   - [`span` Options](#span-options)
+  - [`data_generator` Option](#data_generator-option)
   - [Apex Charts Options Example](#apex-charts-options-example)
   - [Layouts](#layouts)
 - [Known issues](#known-issues)
@@ -117,6 +118,7 @@ The card stricly validates all the options available (but not for the `apex_conf
 | `unit` | string | | v1.0.0 | Override the unit of the sensor |
 | `group_by` | object | | v1.0.0 | See [group_by](#group_by-options) |
 | `invert` | boolean | `false` | NEXT_VERSION | Negates the data (`1` -> `-1`). Usefull to display opposites values like network in (standard)/out (inverted) |
+| `data_generator` | string | | NEXT_VERSION | See [data_generator](#data_generator-option) |
 
 
 ### `show` Options
@@ -211,6 +213,80 @@ Eg:
     end: day
   ```
 
+### `data_generator` Option
+
+Before we start, to learn javascript, google is your friend or ask for help on the [forum](https://community.home-assistant.io/t/apexcharts-card-a-highly-customizable-graph-card/272877) :slightly_smiling_face:
+
+`data_generator` is an advanced feature. It enables you to build your own data out of the last state of a sensor. It completely bypasses the history retrieval and caching mecanism.
+
+You'll need to write a javascript function which returns a `[timestamp, value][]`:
+* `timestamp` is the timestamp of the data in ms
+* `value` is the value of the data as a number or a float, make sure you parse it if it's a string.
+
+Inside your javascript code, you'll have access to those variables:
+* `entity`: the entity object
+* `start` (Date object): the start Date object of the graph currently displayed
+* `end` (Date object): the end Date object of the graph currently displayed
+* `hass`: the complete `hass` object
+* `moment`: the [Moment.JS](https://momentjs.com/) object to help you manipulate time and dates
+
+Let's take this example:
+* My sensor (`sensor.test`) has this state as its last state:
+  ```yaml
+  FirstPeak: High
+  PeakTimes:
+    - '2021-01-27 03:43:00'
+    - '2021-01-27 10:24:00'
+    - '2021-01-27 16:02:00'
+    - '2021-01-27 22:38:00'
+    - '2021-01-28 04:21:00'
+    - '2021-01-28 11:06:00'
+    - '2021-01-28 16:40:00'
+    - '2021-01-28 23:18:00'
+    - '2021-01-29 05:00:00'
+    - '2021-01-29 11:45:00'
+    - '2021-01-29 17:19:00'
+    - '2021-01-29 23:58:00'
+    - '2021-01-30 05:39:00'
+    - '2021-01-30 12:25:00'
+    - '2021-01-30 17:59:00'
+  PeakHeights:
+    - 4.99
+    - 1.41
+    - 4.96
+    - 1.33
+    - 5.22
+    - 1.19
+    - 5.15
+    - 1.14
+    - 5.42
+    - 1.01
+    - 5.3
+    - 0.99
+    - 5.57
+    - 0.87
+    - 5.39
+  unit_of_measurement: m
+  friendly_name: Tides
+  ```
+* This is data in the future, but I want to display them so I need to build them myself using `data_generator`:
+  ```yaml
+  type: custom:apexcharts-card
+  graph_span: 4d # I have 4 days worth of data in the future in the attributes
+  span:
+    start: hour # I want to display from the start of the current hours 4 days into the future
+  series:
+    - entity: sensor.test
+      data_generator: | # This is what builds the data
+        return entity.attributes.PeakTimes.map((peak, index) => {
+          return [new Date(peak), entity.attributes.PeakHeights[index]];
+        });
+  ```
+  The result of this function call would be something like: <br/>
+  `[[1611718980000, 4.99], [1611743040000, 1.41], [1611763320000, 4.96], ...]`
+
+* And this is all you need :tada:
+
 ### Apex Charts Options Example
 
 This is how you could change some options from ApexCharts as described on the [`Options (Reference)` menu entry](https://apexcharts.com/docs/installation/).

src/apexcharts-card.ts

@@ -151,6 +151,10 @@ class ChartsCard extends LitElement {
       if (entityState && this._entities[index] !== entityState) {
         this._entities[index] = entityState;
         updated = true;
+        if (this._graphs && this._graphs[index]) {
+          // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+          this._graphs[index]!.hass = this._hass!;
+        }
       }
     });
     if (updated) {

src/graphEntry.ts

@@ -122,9 +122,6 @@ export default class GraphEntry {
   }
 
   public async _updateHistory(start: Date, end: Date): Promise<boolean> {
-    this._realStart = start;
-    this._realEnd = end;
-
     let startHistory = new Date(start);
     if (this._config.group_by.func !== 'raw') {
       const range = end.getTime() - start.getTime();
@@ -134,62 +131,70 @@ export default class GraphEntry {
     if (!this._entityState || this._updating) return false;
     this._updating = true;
     this._timeRange = moment.range(startHistory, end);
+    let history: EntityEntryCache | undefined = undefined;
 
-    let skipInitialState = false;
+    if (this._config.data_generator) {
+      this._history = this._generateData(start, end);
+    } else {
+      this._realStart = start;
+      this._realEnd = end;
 
-    let history = this._cache ? await this._getCache(this._entityID, this._useCompress) : undefined;
+      let skipInitialState = false;
 
-    if (history && history.span === this._graphSpan) {
-      const currDataIndex = history.data.findIndex((item) => item && new Date(item[0]).getTime() > start.getTime());
-      if (currDataIndex !== -1) {
-        // skip initial state when fetching recent/not-cached data
-        skipInitialState = true;
-      }
-      if (currDataIndex > 4) {
-        // >4 so that the graph has some more history
-        history.data = history.data.slice(currDataIndex === 0 ? 0 : currDataIndex - 4);
-      } else if (currDataIndex === -1) {
-        // there was no state which could be used in current graph so clearing
-        history.data = [];
-      }
-    } else {
-      history = undefined;
-    }
-    const newHistory = await this._fetchRecent(
-      // if data in cache, get data from last data's time + 1ms
-      history && history.data && history.data.length !== 0 && history.data.slice(-1)[0]
-        ? // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-          new Date(history.data.slice(-1)[0]![0] + 1)
-        : startHistory,
-      end,
-      skipInitialState,
-    );
-    if (newHistory && newHistory[0] && newHistory[0].length > 0) {
-      const newStateHistory: EntityCachePoints = newHistory[0].map((item) => {
-        const stateParsed = parseFloat(item.state);
-        return [new Date(item.last_changed).getTime(), !Number.isNaN(stateParsed) ? stateParsed : null];
-      });
-      if (history?.data.length) {
-        history.span = this._graphSpan;
-        history.last_fetched = new Date();
-        history.card_version = pjson.version;
-        if (history.data.length !== 0) {
-          history.data.push(...newStateHistory);
+      history = this._cache ? await this._getCache(this._entityID, this._useCompress) : undefined;
+
+      if (history && history.span === this._graphSpan) {
+        const currDataIndex = history.data.findIndex((item) => item && new Date(item[0]).getTime() > start.getTime());
+        if (currDataIndex !== -1) {
+          // skip initial state when fetching recent/not-cached data
+          skipInitialState = true;
+        }
+        if (currDataIndex > 4) {
+          // >4 so that the graph has some more history
+          history.data = history.data.slice(currDataIndex === 0 ? 0 : currDataIndex - 4);
+        } else if (currDataIndex === -1) {
+          // there was no state which could be used in current graph so clearing
+          history.data = [];
         }
       } else {
-        history = {
-          span: this._graphSpan,
-          card_version: pjson.version,
-          last_fetched: new Date(),
-          data: newStateHistory,
-        };
+        history = undefined;
       }
-
-      if (this._cache) {
-        this._setCache(this._entityID, history, this._useCompress).catch((err) => {
-          log(err);
-          localForage.clear();
+      const newHistory = await this._fetchRecent(
+        // if data in cache, get data from last data's time + 1ms
+        history && history.data && history.data.length !== 0 && history.data.slice(-1)[0]
+          ? // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+            new Date(history.data.slice(-1)[0]![0] + 1)
+          : startHistory,
+        end,
+        skipInitialState,
+      );
+      if (newHistory && newHistory[0] && newHistory[0].length > 0) {
+        const newStateHistory: EntityCachePoints = newHistory[0].map((item) => {
+          const stateParsed = parseFloat(item.state);
+          return [new Date(item.last_changed).getTime(), !Number.isNaN(stateParsed) ? stateParsed : null];
         });
+        if (history?.data.length) {
+          history.span = this._graphSpan;
+          history.last_fetched = new Date();
+          history.card_version = pjson.version;
+          if (history.data.length !== 0) {
+            history.data.push(...newStateHistory);
+          }
+        } else {
+          history = {
+            span: this._graphSpan,
+            card_version: pjson.version,
+            last_fetched: new Date(),
+            data: newStateHistory,
+          };
+        }
+
+        if (this._cache) {
+          this._setCache(this._entityID, history, this._useCompress).catch((err) => {
+            log(err);
+            localForage.clear();
+          });
+        }
       }
     }
 
@@ -218,6 +223,37 @@ export default class GraphEntry {
     return this._hass?.callApi('GET', url);
   }
 
+  private _generateData(start: Date, end: Date): EntityEntryCache {
+    let data;
+    try {
+      data = new Function(
+        'entity',
+        'start',
+        'end',
+        'hass',
+        'moment',
+        `'use strict'; ${this._config.data_generator}`,
+      ).call(this, this._entityState, start, end, this._hass, moment);
+    } catch (e) {
+      const funcTrimmed =
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        this._config.data_generator!.length <= 100
+          ? // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+            this._config.data_generator!.trim()
+          : // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+            `${this._config.data_generator!.trim().substring(0, 98)}...`;
+      e.message = `${e.name}: ${e.message} in '${funcTrimmed}'`;
+      e.name = 'Error';
+      throw e;
+    }
+    return {
+      span: 0,
+      card_version: pjson.version,
+      last_fetched: new Date(),
+      data,
+    };
+  }
+
   private _dataBucketer(): HistoryBuckets {
     const ranges = Array.from(this._timeRange.reverseBy('milliseconds', { step: this._groupByDurationMs })).reverse();
     // const res: EntityCachePoints[] = [[]];

src/types-config-ti.ts

@@ -35,6 +35,7 @@ export const ChartCardSeriesExternalConfig = t.iface([], {
   "extend_to_end": t.opt("boolean"),
   "unit": t.opt("string"),
   "invert": t.opt("boolean"),
+  "data_generator": t.opt("string"),
   "group_by": t.opt(t.iface([], {
     "duration": t.opt("string"),
     "func": t.opt("GroupByFunc"),

src/types-config.ts

@@ -29,6 +29,7 @@ export interface ChartCardSeriesExternalConfig {
   extend_to_end?: boolean;
   unit?: string;
   invert?: boolean;
+  data_generator?: string;
   group_by?: {
     duration?: string;
     func?: GroupByFunc;