add wiki for deployment

deployments/README.md

@@ -0,0 +1,57 @@
+# Deployment
+This folder contains all 
+
+## Tech stack
+- [Docker](https://docs.docker.com/): for the containerization
+- [Kubernetes](https://kubernetes.io/docs/home/): container orchestraction platform
+- [Ansible](https://docs.ansible.com/ansible/latest/index.html): remote deployment executor
+- [OpenResty](https://openresty.org/en/): for the web proxy
+
+## File structures
+- `kubernetes/`: config files for kubernetes
+  - `monitoring/`: monitoring namespace, which monitor the testing infrastructur itself
+    - `blackbox_exporter/`: for generic HTTP service prometheus exporter
+    - `grafana/`: for grafana monitoring dashboards
+    - `postgres_exporter/`: for PostgreSQL database prometheus exporter
+    - `prometheus/`: for prometheus TSDB of the testing infrastructure
+  - `performance`: testing infrastructure services
+    - `grafana/`: for grafana monitoring dashboards of the testing data
+    - `openapi/`: for the OpenAPI documentation of the Django API
+    - `performance-storage-service/`: the Django API web service which collect and validate testing results
+    - `timescaledb`: the TimeScale DB for storing the testing results
+  - `namespaces.yml`: defines the namespaces for the kubernetes cluster
+- `playbooks/`: contains all the [ansible playbooks](https://docs.ansible.com/ansible/latest/user_guide/playbooks.html), which are the invocation points for all the deployment tasks
+- `roles/`: contains all the [ansible roles](https://docs.ansible.com/ansible/latest/user_guide/playbooks_reuse_roles.html), which are used directly by the [ansible playbooks](https://github.com/cmu-db/noisepage-stats/tree/master/deployments/playbooks) above
+- `scripts/`: contains shell scripts which are used during the deployments
+- `ansible.cfg`: the project-wide [configuration of ansible](https://docs.ansible.com/ansible/latest/reference_appendices/config.html#ansible-configuration-settings)
+- `inventory`: the [INI style configuration](https://docs.ansible.com/ansible/2.9_ja/plugins/inventory/ini.html) of the ansible hosts and vars
+- `Jenkinsfile`: the configuration of Jenkins pipeline, which defines the CD processes
+
+## Quick guide to deployments
+
+### How to add a namespace [optional]
+-  Normally, you do **NOT** need to do it, because all the testing infrastructure services should be under `performance` and all the monitoring services of the testing infrastructure should be under `monitoring`.
+- If you really need to add a new namespace for the kubernetes
+  - Declare the namespace of your service in the `namespaces.yml`
+  - Trigger the CD by pushing your code changes to the GitHub. The Jenkins should pick up the change and run the following command to execute the change.
+  ```bash
+  ansible-playbook -i inventory playbooks/create-namespaces.yml
+  ```
+
+### To deploy a service for testing infrastructure
+- Create a service in `kubernetes/performance/`. In that folder
+  - [optional] Create config files if necessary, which may include
+    - `config-map.yml`: for file-based service configuration
+    - `persistent-volume.yml`: for Kubernetes persistent volume declaration
+    - `persistent-volume-claim.yml`: for Kubernetes persistent volume claim
+  - Create a deployment config file
+    - Create a `deployment.yml` if it is a stateless service
+    - Create a `statefulset.yml` if it is a stateful service
+  - Create a service config file, which serves as the proxy of the service
+    - Use `NodePort` by default
+- Create an ansible playbook in `playbooks/` as the invocation point of the deployment of your service
+- [optional] Add your service public port as a new [NGINX location in OpenResty config](https://docs.nginx.com/nginx/admin-guide/web-server/reverse-proxy/) if your service has a public HTTP endpoint
+- [optional] Add ansible roles to `roles/` for any additional roles created for your service
+- [optional] Add any ansible vars to `inventory` that are specific to your service deployment
+
+