Update README for networking

README.md

@@ -38,7 +38,7 @@ edb-terraform generate \
   --infra-file edb-terraform/docs/examples/aws/edb-ra-3.yml
 cd example
 terraform init
-terraform apply
+terraform apply -var "force_dynamic_ip=true"
 terraform destroy
 ```
 
@@ -219,3 +219,57 @@ edb-terraform setup
 ├── terraform.tfvars.json # Automatically detected Terraform variables. Original values under `edb-terraform/terraform.tfvars.yml`
 └── common_vars.tf # Terraform placeholder variables used by all providers
 ```
+
+## Configurations
+Each provider has a:
+- set of example configurations available under the docs directory.
+- spec object within `variables.tf` of its specification module.
+
+AWS
+- [spec](./edbterraform/data/terraform/aws/modules/specification/variables.tf)
+- [examples](./docs/examples/aws/machines-v2.yml)
+
+Azure
+- [spec](./edbterraform/data/terraform/azure/modules/specification/variables.tf)
+- [examples](./docs/examples/azure/machines-v2.yml)
+
+GCloud
+- [spec](./edbterraform/data/terraform/gcloud/modules/specification/variables.tf)
+- [examples](./docs/examples/gcloud/machines-v2.yml)
+
+### Networking
+By default, there are 4 `defaults` availabe when defining ports:
+- `public` - ports for publics access
+- `service` - ports for limited access
+- `internal` - ports for all internal access
+- `""` - ports without defaults (Default)
+
+When defining `service` ports,
+users can use 2 variables to dynamically update the allowed ips on top of adding values under the `cidrs` key.
+This is meant for single time use and in most cases you should set the expected cidr ranges.
+- `service_cidrblocks` - a list of cidrblocks for service access.
+- `force_dynamic_ip` - use an http endpoint to get the current public ip and appended to service_cidrblocks.
+
+> :warning:  
+> Policy rules might block generic rules such as `0.0.0.0/0`,  
+>   which is often used by users with changing ips.  
+> This can cause unexpected ssh errors since resources are available before policies are applied.  
+> If possible, make use of a jump host to have a set of persistent ips.  
+> Otherwise, make use of the `force_dynamic_ip` or `service_cidrblocks` options to dynamically set service ips.
+
+> :warning:  
+> Only AWS supports security groups, which allows for more flexibility with port configurations.  
+> We mimic the functionality of security groups for Azure and GCloud to allow ports to be defined per instance.  
+
+### Environment variables
+Terraform allows for top-level variables to be defined with cli arguments or environment variables.
+
+For any variable you can define:
+- Environment variables for all stages: `TF_VAR_ARGS=<CLI ARGS>`
+- Environment variables for a targetted stage: `TF_VAR_ARGS_<stage>=<CLI ARGS>`
+- Environment variables for root variables: `TF_VAR_<variable>=<ARGS>`
+- CLI Arguments for root variables: `-var <variable>=<ARGS>`
+
+Example variable: 
+- `TF_VAR_force_dynamic_ip=true` is the same as `-var force_dynamic_ip=true`
+- `TF_VAR_service_cidrblocks='["0.0.0.0/0"]'`