chore(docs): Added documentation about the metadata router

docs/endpoints/list-endpoints.md

@@ -7,10 +7,11 @@ https://kekkai-api.redume.su/api/
 
 
 ## API Endpoints
-Kekkai has 3 API endpoints: `getRate`, `getChart` and `configurations`. 
+Kekkai has 3 API endpoints: `getRate`, `getChart` and `metadata`. 
 Below you will find a list of parameters that each endpoint requires and a description of what the API does.
 
 | Service      | API Endpoint                                 | Description                                                                                 |
-|--------------|--------------------------------------------------------|--------------------------------------------------------------------|
+|--------------|----------------------------------------------|---------------------------------------------------------------------------------------------|
 | Get Rate     | `https://kekkai-api.redume.su/api/getRate/`  | Get currency exchange rate for a specific day or period                                     |
-| Create Chart | `https://kekkai-api.redume.su/api/getChart`            | Creating a chart with exchange rate                                |
+| Create Chart | `https://kekkai-api.redume.su/api/getChart/` | Creating a chart with exchange rate                                                         |
+| Metadata     | `https://kekkai-api.redume.su/api/metadata/` | Shows the last and first dates of currency rate collection, as well as available currencies |

docs/endpoints/metadata.md

@@ -0,0 +1,60 @@
+Currencies are identified by standard three-letter `ISO 4217` currency codes.
+
+## Get data on available dates and currencies.
+
+### Request
+=== "Shell"
+=== "Curl"
+```bash
+curl --request GET \
+--url https://kekkai-api.redume.su/api/metadata/
+```
+
+=== "Python"
+    === "Requests"
+        ```py
+        import requests
+        
+        res = requests.get('https://kekkai-api.redume.su/api/metadata/', timeout=3)
+
+        print(res.json())
+        ```
+
+=== "Node.JS"
+    === "Axios"
+        ```js
+        const axios = require('axios');
+
+        axios.get('https://kekkai-api.redume.su/api/metadata/')
+            .then((res) => {
+                console.log(JSON.stringify(res.json()));
+            })
+            .catch((err) => {
+                console.error(err);
+            });
+        ```
+
+### Response
+!!! info "Output"
+    ```json
+    {
+        "first_date": "2024-11-26T21:00:00.000Z",
+        "last_date": "2025-01-01T21:00:00.000Z",
+        "currencies": {
+            "crypto": [
+                "USDT",
+                "TON",
+                "BTC",
+                "ETH"
+            ],
+            "fiat": [
+                "USD",
+                "RUB",
+                "EUR",
+                "UAH",
+                "TRY",
+                "KZT"
+            ]
+        }
+    }
+    ```

mkdocs.yml

@@ -18,6 +18,7 @@ nav:
     - Endpoints list: endpoints/list-endpoints.md
     - Get currency rate - /api/getRate: endpoints/get-rate.md
     - Create Charts - /api/getChart: endpoints/create-chart.md
+    - Get Metadata - /api/metadata: endpoints/metadata.md
   - Config:
     - Configure config.yaml: config/config-yaml.md
     - Configure .env: config/config-env.md