doc: add more documentation

CONTRIBUTING.md

@@ -29,21 +29,22 @@ this operator.
 
 ## Developing
 
-You can use the environments created by `tox` for development:
+You can use the environments created by `tox` for development. It helps
+install `pre-commit` and `mypy` type checker.
 
 ```shell
-tox --notest -e unit
-source .tox/unit/bin/activate
+$ tox -e dev
+$ source .tox/unit/bin/activate
 ```
 
 ## Testing
 
 ```shell
-tox -e fmt           # update your code according to linting rules
-tox -e lint          # code style
-tox -e unit          # unit tests
-tox -e integration   # integration tests
-tox                  # runs 'fmt', 'lint', and 'unit' environments
+$ tox -e fmt           # update your code according to linting rules
+$ tox -e lint          # code style
+$ tox -e unit          # unit tests
+$ tox -e integration   # integration tests
+$ tox                  # runs 'fmt', 'lint', and 'unit' environments
 ```
 
 ## Build the charm
@@ -58,13 +59,13 @@ $ charmcraft pack
 
 ```shell
 # Create a juju model
-juju add-model dev
+$ juju add-model dev
 
 # Enable DEBUG logging
-juju model-config logging-config="<root>=INFO;unit=DEBUG"
+$ juju model-config logging-config="<root>=INFO;unit=DEBUG"
 
 # Deploy the charm
-juju deploy ./glauth-k8s_ubuntu-*-amd64.charm --resource oci-image=$(yq eval '.resources.oci-image.upstream-source' metadata.yaml)
+$ juju deploy ./glauth-k8s_ubuntu-*-amd64.charm --resource oci-image=$(yq eval '.resources.oci-image.upstream-source' metadata.yaml)
 ```
 
 ## Observability

README.md

@@ -29,15 +29,51 @@ $ juju integrate glauth-k8s postgresql-k8s
 
 ## Integrations
 
-TBD.
+### `postgresql_client` Integration
+
+The `glauth-k8s` charmed operator requires the integration with the
+`postgres-k8s` charmed operator following the [`postgresql_client` interface
+protocol](https://github.com/canonical/charm-relation-interfaces/tree/main/interfaces/postgresql_client/v0).
+
+```shell
+$ juju integrate glauth-k8s postgresql-k8s
+```
+
+### `ldap` Integration
+
+The `glauth-k8s` charmed operator offers the `ldap` integration with any
+LDAP client charmed operator following
+the [`ldap` interface protocol](https://github.com/canonical/charm-relation-interfaces/tree/main/interfaces/ldap/v0).
+
+```shell
+$ juju integrate <ldap-client-charm>:ldap glauth-k8s:ldap
+```
+
+### `glauth_auxiliary` Integration
+
+The `glauth-k8s` charmed operator provides the `glauth_auxiliary`
+integration with
+the [`glauth-utils` charmed operator](https://github.com/canonical/glauth-utils)
+to deliver necessary auxiliary configurations.
+
+```shell
+$ juju integrate glauth-k8s glauth-utils
+```
 
 ## Configurations
 
-TBD.
+The `glauth-k8s` charmed operator offers the following charm configuration
+options.
 
-## Actions
+| Charm Config Option | Description                                                      | Example                                                 |
+|:-------------------:|------------------------------------------------------------------|---------------------------------------------------------|
+|      `base-dn`      | The portion of the DIT in which to search for matching entries   | `juju config <charm-app> base-dn="dc=glauth,dc=com"`    |
+|     `hostname`      | The hostname of the LDAP server in `glauth-k8s` charmed operator | `juju config <charm-app> hostname="ldap.canonical.com"` |
 
-TBD.
+> ⚠️ **NOTE**
+>
+> The `hostname` should **NOT** contain the ldap scheme (e.g. `ldap://`) and
+> port.
 
 ## Contributing