Add a k6-loadgen chaos fault to mkdocs

mkdocs/docs/experiments/categories/contents.md

@@ -215,6 +215,23 @@ While Chaos Experiments under the Generic category offer the ability to induce c
   </tr>
 </table>
 
+### Load Chaos
+
+Load chaos contains different chaos experiments to test the app/platform service availability. It will install all the experiments which can be used to inject load into the services like VMs, Pods and so on.
+
+<table style="width: 100%;">
+  <tr>
+    <th>Experiment Name</th>
+    <th>Description</th>
+    <th>User Guide</th>
+  </tr>
+  <tr>
+    <td>k6 Load Generator</td>
+    <td>Generate load using single js script</td>
+    <td><a href="/litmus/experiments/categories/load/k6-loadgen">k6-loadgen</a></td>
+  </tr>
+</table>
+
 <hr/>
 
 ##  Cloud Infrastructure

mkdocs/docs/experiments/categories/load/k6-loadgen.md

@@ -0,0 +1,199 @@
+## Introduction
+
+[k6](https://k6.io/) loadgen fault simulates load generation on the target hosts for a specific chaos duration. This fault:
+- Slows down or makes the target host unavailable due to heavy load.
+- Checks the performance of the application or process running on the instance.
+Support [various types](https://grafana.com/docs/k6/latest/testing-guides/test-types/) of load testing (ex. spike, smoke, stress)
+
+!!! tip "Scenario: Load generating with k6"    
+    ![k6-loadgen](../../images/k6-loadgen.png)
+
+## Prerequisites
+
+??? info "Verify the prerequisites" 
+    - Ensure that Kubernetes Version > 1.16 
+    - Ensure that the Litmus Chaos Operator is running by executing <code>kubectl get pods</code> in operator namespace (typically, <code>litmus</code>). If not, install from <a href="https://docs.litmuschaos.io/docs/getting-started/installation">here</a>
+    - Ensure to create a Kubernetes secret having the JS script file in the `Chaos Infrastructure`'s namespace (`litmus` by default). The simplest way to create a secret object looks like this:
+            ```bash
+            kubectl create secret generic k6-script \
+                --from-file=script.js=<<script-path>> -n <<chaos_infrastructure_namespace>>
+            ```
+
+## Minimal RBAC configuration example (optional)
+
+!!! tip "NOTE"   
+    If you are using this experiment as part of a litmus workflow scheduled constructed & executed from chaos-center, then you may be making use of the [litmus-admin](https://litmuschaos.github.io/litmus/litmus-admin-rbac.yaml) RBAC, which is pre installed in the cluster as part of the agent setup.
+
+    ??? note "View the Minimal RBAC permissions"
+
+        ```yaml
+        ---
+        apiVersion: v1
+        kind: ServiceAccount
+        metadata:
+        name: k6-loadgen-sa
+        namespace: default
+        labels:
+        name: k6-loadgen-sa
+        ---
+        apiVersion: rbac.authorization.k8s.io/v1
+        kind: Role
+        metadata:
+        name: k6-loadgen-sa
+        namespace: default
+        labels:
+        name: k6-loadgen-sa
+        rules:
+        - apiGroups: ["","litmuschaos.io","batch","apps"]
+          resources: ["pods","configmaps","jobs","pods/exec","pods/log","events","chaosengines","chaosexperiments","chaosresults"]
+          verbs: ["create","list","get","patch","update","delete","deletecollection"]
+        ---
+        apiVersion: rbac.authorization.k8s.io/v1
+        kind: RoleBinding
+        metadata:
+        name: k6-loadgen-sa
+        namespace: default
+        labels:
+        name: k6-loadgen-sa
+        roleRef:
+        apiGroup: rbac.authorization.k8s.io
+        kind: Role
+        name: k6-loadgen-sa
+        subjects:
+        - kind: ServiceAccount
+          name: k6-loadgen-sa
+          namespace: default
+
+        ```
+        Use this sample RBAC manifest to create a chaosServiceAccount in the desired (app) namespace. This example consists of the minimum necessary role permissions to execute the experiment.
+
+## Experiment tunables
+
+??? info "check the experiment tunables" 
+    <h2>Optional Fields</h2>
+
+    <table>
+      <tr>
+        <th> Variables </th>
+        <th> Description  </th>
+        <th> Notes </th>
+      </tr>
+      <tr>
+        <td> TOTAL_CHAOS_DURATION  </td>
+        <td> The time duration for chaos injection (seconds) </td>
+        <td> Defaults to 20s </td>
+      </tr>
+      <tr>
+        <td> CHAOS_INTERVAL  </td>
+        <td> Time interval b/w two successive k6-loadgen (in sec) </td>
+        <td> If the CHAOS_INTERVAL is not provided it will take the default value of 10s </td>
+      </tr>
+      <tr>
+        <td> RAMP_TIME </td>
+        <td> Period to wait before injection of chaos in sec </td>
+        <td> </td>
+      </tr>
+      <tr>
+        <td> LIB_IMAGE  </td>
+        <td> LIB Image used to excute k6 engine </td>
+        <td> Defaults to <code>ghcr.io/grafana/k6-operator:latest-runner</code></td>
+      </tr>
+      <tr>
+        <td> LIB_IMAGE_PULL_POLICY  </td>
+        <td> LIB Image pull policy </td>
+        <td> Defaults to <code>Always</code> </td> 
+      </tr>
+      <tr>
+        <td> SCRIPT_SECRET_NAME </td>
+        <td> Provide the k8s secret name of the JS script to run k6. </td>
+        <td> Default value: k6-script </td>
+      </tr>
+      <tr>
+        <td> SCRIPT_SECRET_KEY </td>
+        <td> Provide the key of the k8s secret named SCRIPT_SECRET_NAME </td>
+        <td> Default value: script.js </td>
+      </tr>
+    </table>
+
+## Experiment Examples
+
+### Common and Pod specific tunables
+
+Refer the [common attributes](../common/common-tunables-for-all-experiments.md) and [Pod specific tunable](common-tunables-for-pod-experiments.md) to tune the common tunables for all experiments and pod specific tunables.  
+
+### Custom k6 configuration
+You can add k6 options(ex hosts, thresholds) in the script `options` object. More details can be found [here](https://grafana.com/docs/k6/latest/using-k6/k6-options/)
+
+### Custom Secret Name and Secret Key
+
+You can provide the secret name and secret key of the JS script to be used for k6-loadgen. The secret should be created in the same namespace where the `chaos infrastructure` is created. For example, if the chaos infrastructure is created in the `litmus` namespace, then the secret should also be created in the `litmus` namespace. 
+
+You can write a JS script like below. If you want to know more about the script, checkout [this documentation](https://grafana.com/docs/k6/latest/using-k6/).
+
+[embedmd]:# (./k6-loadgen/custom-script.js js)
+```js
+import http from 'k6/http';
+import { sleep } from 'k6';
+export const options = {
+    vus: 100,
+    duration: '30s',
+};
+export default function () {
+    http.get('http://<<target_domain_name>>/');
+    sleep(1);
+}
+```
+
+Then create a secret with the above script.
+
+```bash
+kubectl create secret generic custom-k6-script \
+  --from-file=script.js=custom-script.js -n <<chaos_infrastructure_namespace>>
+```
+
+And If we want to use `custom-k6-script` secret and `custom-script.js` as the secret key, then the experiment tunable will look like this:
+
+[embedmd]:# (./k6-loadgen/k6-loadgen.yaml yaml)
+```yaml
+---
+apiVersion: litmuschaos.io/v1alpha1
+kind: ChaosEngine
+metadata:
+  name: nginx-chaos
+  namespace: default
+spec:
+  engineState: 'active'
+  chaosServiceAccount: litmus-admin
+  experiments:
+    - name: k6-loadgen
+      spec:
+        components:
+          env:
+            # set chaos duration (in sec) as desired
+            - name: TOTAL_CHAOS_DURATION
+              value: "30"
+
+            # Interval between chaos injection in sec
+            - name: CHAOS_INTERVAL
+              value: "30"
+
+            # Period to wait before and after injection of chaos in sec
+            - name: RAMP_TIME
+              value: "0"
+
+            # Provide the secret name of the JS script
+            - name: SCRIPT_SECRET_NAME
+              value: "custom-k6-script"
+
+            # Provide the secret key of the JS script
+            - name: SCRIPT_SECRET_KEY
+              value: "custom-script.js"
+
+            # Provide the image name of the helper pod
+            - name: LIB_IMAGE
+              value: "ghcr.io/grafana/k6-operator:latest-runner"
+
+            # Provide the image pull policy of the helper pod
+            - name: LIB_IMAGE_PULL_POLICY
+              value: "Always"
+```

mkdocs/docs/experiments/categories/load/k6-loadgen/custom-script.js

@@ -0,0 +1,10 @@
+import http from 'k6/http';
+import { sleep } from 'k6';
+export const options = {
+    vus: 100,
+    duration: '30s',
+};
+export default function () {
+    http.get('http://<<target_domain_name>>/');
+    sleep(1);
+}

mkdocs/docs/experiments/categories/load/k6-loadgen/k6-loadgen.yaml

@@ -0,0 +1,41 @@
+---
+apiVersion: litmuschaos.io/v1alpha1
+kind: ChaosEngine
+metadata:
+  name: nginx-chaos
+  namespace: default
+spec:
+  engineState: 'active'
+  chaosServiceAccount: litmus-admin
+  experiments:
+    - name: k6-loadgen
+      spec:
+        components:
+          env:
+            # set chaos duration (in sec) as desired
+            - name: TOTAL_CHAOS_DURATION
+              value: "30"
+
+            # Interval between chaos injection in sec
+            - name: CHAOS_INTERVAL
+              value: "30"
+
+            # Period to wait before and after injection of chaos in sec
+            - name: RAMP_TIME
+              value: "0"
+
+            # Provide the secret name of the JS script
+            - name: SCRIPT_SECRET_NAME
+              value: "custom-k6-script"
+
+            # Provide the secret key of the JS script
+            - name: SCRIPT_SECRET_KEY
+              value: "custom-script.js"
+
+            # Provide the image name of the helper pod
+            - name: LIB_IMAGE
+              value: "ghcr.io/grafana/k6-operator:latest-runner"
+
+            # Provide the image pull policy of the helper pod
+            - name: LIB_IMAGE_PULL_POLICY
+              value: "Always"

mkdocs/mkdocs.yml

@@ -120,6 +120,8 @@ nav:
             - Spring Boot Exceptions: experiments/categories/spring-boot/spring-boot-exceptions.md
             - Spring Boot Latency: experiments/categories/spring-boot/spring-boot-latency.md
             - Spring Boot Faults: experiments/categories/spring-boot/spring-boot-faults.md
+        - Load:
+            - k6 Load Generator: experiments/categories/load/k6-loadgen.md
       - Cloud Infrastructure:
         - AWS: 
             - EC2: