New options for Prometheus rw output (#1366)

Documented the new options

---------

Co-authored-by: Oleg Bespalov <[email protected]>
Co-authored-by: Théo Crevon <[email protected]>

src/data/markdown/translated-guides/en/04 Results output/200 Real-time/00 Prometheus remote write.md

@@ -158,14 +158,18 @@ k6 has special options for remote write output.
 | Name | Type |  Description |
 | ---- | ---- |  ----------- |
 | `K6_PROMETHEUS_RW_SERVER_URL` | `string`  | URL of the Prometheus remote write implementation's endpoint. Default is ``http://localhost:9090/api/v1/write`` |
-| `K6_PROMETHEUS_RW_HEADERS_<here-the-header-key>` | list of `string` | Additional headers to include in the HTTP requests. `K6_PROMETHEUS_RW_HEADERS_X-MY-HEADER=foo`|
-| `K6_PROMETHEUS_RW_USERNAME` | `string` | User for the HTTP Basic authentication at the Prometheus remote write endpoint. |
-| `K6_PROMETHEUS_RW_PASSWORD` | `string` | Password for the HTTP Basic authentication at the Prometheus remote write endpoint. |
-| `K6_PROMETHEUS_RW_PUSH_INTERVAL` | `string` | Interval of the metrics' aggregation and upload to the endpoint. Default is `5s` |
+| `K6_PROMETHEUS_RW_HEADERS_<header-key>` | `string` | An additional header to include in the HTTP requests can be set using this described format. For example, `K6_PROMETHEUS_RW_HEADERS_MY-HEADER-CUSTOM-KEY=foo`. |
+| `K6_PROMETHEUS_RW_HTTP_HEADERS` | comma-separated list of key values | Additional headers to include in the HTTP requests. `K6_PROMETHEUS_RW_HTTP_HEADERS=key1:value1,key2:value2`. |
+| `K6_PROMETHEUS_RW_PUSH_INTERVAL` | `string` | Interval of the metrics' aggregation and upload to the endpoint. Default is `5s`. |
 | `K6_PROMETHEUS_RW_TREND_AS_NATIVE_HISTOGRAM` | `boolean` | If true, it maps the all defined trend metrics as [Native Histograms](#prometheus-native-histogram). Default is `false`. |
-| `K6_PROMETHEUS_RW_TREND_STATS` | list of `string` |  If Native Histogram is not enabled then it defines the stats functions to map for the all defined trend metrics. It's a comma-separated list of stats functions to include (e.g. `p(90),avg,sum`). Check the trend section to know the entire set of the supported stats. Default is `p(99)` |
+| `K6_PROMETHEUS_RW_TREND_STATS` | list of `string` |  If Native Histogram is not enabled then it defines the stats functions to map for the all defined trend metrics. It's a comma-separated list of stats functions to include (e.g. `p(90),avg,sum`). Check the trend section to know the entire set of the supported stats. Default is `p(99)`. |
 | `K6_PROMETHEUS_RW_INSECURE_SKIP_TLS_VERIFY` | `boolean` | If true, the HTTP client skips TLS verification on the endpoint. Default is `false`. |
 | `K6_PROMETHEUS_RW_STALE_MARKERS` | `boolean` | If true, the output at the end of the test marks all the seen time series as stale. Default is `false`. |
+| `K6_PROMETHEUS_RW_USERNAME` | `string` | Username for the HTTP Basic authentication at the Prometheus remote write endpoint. |
+| `K6_PROMETHEUS_RW_PASSWORD` | `string` | Password for the HTTP Basic authentication at the Prometheus remote write endpoint. |
+| `K6_PROMETHEUS_RW_CLIENT_CERTIFICATE` | `string` | A path to the PEM (Privacy-Enhanced Mail) formatted client certificate. |
+| `K6_PROMETHEUS_RW_CLIENT_CERTIFICATE_KEY` | `string` | A path to the PEM formatted client private key. |
+| `K6_PROMETHEUS_RW_BEARER_TOKEN` | `string` | Sets the Authorization Bearer Token Header. |
 
 ### Stale trend metrics
 
@@ -249,4 +253,4 @@ Clone the repository to get started and follow these steps for using the [docker
 
 3. After running the test, visit [http://localhost:3000](http://localhost:3000). If you enabled native histograms, select the **k6 Prometheus (Native Histograms)** dashboard; otherwise, select the **k6 Prometheus** Dashboard.
 
-  ![k6 Prometheus Dashboard](./images/Prometheus/k6-prometheus-dashboard.png)
+![k6 Prometheus Dashboard](./images/Prometheus/k6-prometheus-dashboard.png)