Added Image Registry and ChaosHub docs (#79)

* Added image registry and ChaosHub docs

Signed-off-by: Amit Kumar Das <amit@chaosnative.com>

* Minor changes

Signed-off-by: Amit Kumar Das <amit@chaosnative.com>

* Added before you begin and learn more section in image registry

Signed-off-by: Amit Kumar Das <amit@chaosnative.com>

* Minor changes

Signed-off-by: Amit Kumar Das <amit@chaosnative.com>

Co-authored-by: Vedant Shrotria <40681425+Jonsy13@users.noreply.github.com>

website/docs/concepts/chaoshub.md

@@ -4,4 +4,87 @@ title: ChaosHub
 sidebar_label: ChaosHub
 ---
 
-## Coming soon
+---
+
+ChaosHub allows you to orchestrate workflows from the Public **[ChaosHub](http://hub.litmuschaos.io/)** or an alternate source for the Experiments (basically, a **[fork](https://github.com/litmuschaos/chaos-charts)** of the public hub with custom experiments).
+
+## Prerequisites
+The following are the prerequisites for creating a Chaos Workflow:
+- [ChaosCenter](chaos-center)
+- [ChaosAgent](agent)
+- Fork of [Chaos-Charts](https://github.com/litmuschaos/chaos-charts) repository  
+
+:::note
+  An active internet connection is required to clone the git repository for the first time installation.
+:::
+
+## Connecting a Git repository using ChaosHub
+With ChaosHub, you can construct chaos workflows by selecting, tuning and sequencing different experiments together from their connected ChaosHubs.
+
+You can make changes in your forked repositories and sync it with the Portal to get the latest changes from the fork.
+
+By default, a Public ChaosHub is provided when the ChaosCenter is installed for the first time. 
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-default.png').default} width="800"  />
+
+### 1. Connect a Public Git Repository
+
+You can connect to a public Git repository by simply providing the following details:
+- Hub Name 
+- Git URL of the forked repository
+- Branch Name 
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-add-public.png').default} width="800"  />
+
+### 2. Connect a Private Git Repository
+
+To add a Private Hub, you need provide the Hub name, Git URL of the forked repository and the Branch name similar to that of Public Hub and the repository can be connected by 2 methods:
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-add-private.png').default} width="800"  />
+
+#### a. Access Token
+Personal Access Tokens are used as an alternative to the password for authentication to Git services. 
+
+#### b. SSH Key
+Just like the Access Token , SSH keys are used for the authentication. These keys come in pairs, a public key that is shared with the Git Services and a private key that is stored with you. 
+SSH link of the repository should be provided if you select this method.
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-after-add.png').default} width="800"  />
+
+## Syncing a ChaosHub
+If some changes are made into the git repository, you can reflect these changes in the hub by selecting the **Refresh Hub** option from the ChaosHub card.
+
+## Editing a ChaosHub
+To make changes in a hub like changing the name, branch, access token etc, you can select the **Edit Hub** option from the ChaosHub card.
+
+## Workflows and Experiments in a ChaosHub
+### 1. View the PreDefined Workflows
+After connecting a ChaosHub, you can view the different pre-defined workflows present in the ChaosHub.
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-predefined-wf.png').default} width="800"  />
+
+### 2. View the Chaos-Charts
+Similarly, you can view the different charts and the experiment. These charts are sorted according to different categories like generic, aws, azure, kube-components etc.
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-chaos-charts.png').default} width="800"  />
+
+### 3. View the experiment details
+You can select one of the chart and can examine the experiment details.
+The experiment page consists of all the important details like the description of the experiment, a tutorial video, the maintainer of the experiment etc.
+You can also find experiment yaml link, RBAC link and the Chaos Engine yaml link of the experiment.
+These yaml links are required for the creation of Custom Chaos Workflows.
+
+<img src={require('../assets/concepts/chaoshub/chaoshub-exp-details.png').default} width="800"  />
+
+## Disconnect a ChaosHub
+To remove a ChaosHub from a project, you can select the **Disconnect Hub** option from the ChaosHub card. 
+
+## Summary
+ChaosHubs are basically a collection of different clones of the Chaos-Charts repository, which consists of a variety of experiments and pre-defined workflows. You can use a ChaosHub to construct a custom chaos workflow and tune it according to the use-case. These ChaosHubs can also be synced with the latest changes. New experiments and pre-defined workflows can also be added in the repository which can be directly used in the ChaosCenter. 
+
+## Resources
+<iframe width="560" height="315" src="https://www.youtube.com/embed/qO-lfmorcus" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+
+## Learn More
+- [What is a Chaos Workflow](chaos-workflow)
+- [Examine the ChaosResult](chaos-result)

website/docs/user-guides/image-registry.md

@@ -3,5 +3,60 @@ id: image-registry
 title: Using different Image Registries in a Workflow
 sidebar_label: Using different Image Registries
 ---
+---
+
+A container image registry can be defined as a collection of repositories that store container image.
+These can be either public or private. Few of the container image registries are Docker, Red Hat Quay, Google Container Registry. 
+By default LitmusChaos uses DockerHub for managing the different images. These images are then used in Chaos Workflows. Few images that are used in the Litmus workflows are `litmuschaos:k8s`, `litmuschaos:litmus-checker` etc.
+With ChaosCenter, you get the privilege to use your own/custom image registries for Chaos Workflows.
+
+## Before you begin
+To understand the concept of Image Registry, make sure you are aware of [Chaos Workflow](../concepts/chaos-workflow) and the different image registries that are used in it.
+
+## Steps to Update Chaos Workflow Image Registry
+To updated the Chaos Workflow Image Registry, you can go to Settings in ChaosCenter. In settings, there will be tab named Image Registry. On clicking the Image Registry tab, you can see that the default Registry server is `docker.io`, Registry name is `litmuschaos` and it is a Public registry.
+
+<img src={require('../assets/user-guides/image-registry/img-registry-tab.png').default} width="800"  />
+<br/><br/>
+
+To update this, click on the `Use Custom Values` option and provide the following details:
+1. Registry Server
+2. Registry Name
+3. Registry Type `Public/Private`
+
+<img src={require('../assets/user-guides/image-registry/img-registry-update.png').default} width="800"  />
+<br/><br/>
+
+If the Registry Type is `Private`, make sure to provide the secret and the namespace where the secret is present.
+
+Once the details are provided, click on the `Save Changes` button and you can see the updated Image Registry changes.
+
+<img src={require('../assets/user-guides/image-registry/img-registry-updated.png').default} width="800"  />
+
+<br/><br/>
+
+Now while scheduling a workflow, the image registry changes will be visible. Here's the code snippet from a Chaos Workflow after the image registry change.
+
+```yaml
+- name: install-application
+      container:
+        image: docker.io/testing-reg/litmus-app-deployer:latest
+        args:
+          - -namespace=bank
+          - -typeName=resilient
+          - -operation=apply
+          - -timeout=400
+          - -app=bank-of-anthos
+          - -scope=cluster
+    - name: install-chaos-experiments
+      container:
+        image: docker.io/testing-reg/k8s:latest
+```
+
+## Learn More
+- [What is a Chaos Workflow](../concepts/chaos-workflow)
+- [What is ChaosCenter](../concepts/chaos-center)
+
+
+
 
-## Coming soon