add readme file (#12)

Co-authored-by: Jannik Clausen <[email protected]>

README.md

@@ -1,2 +1,104 @@
 # atlas-provider-django
-Django provider for atlasgo.io
+
+Load [Django](https://www.djangoproject.com/) models into an [Atlas](https://atlasgo.io) project.
+
+### Use-cases
+1. **Declarative migrations** - use a Terraform-like `atlas schema apply --env django` to apply your Django schema to the database.
+2. **Automatic migration planning** - use `atlas migrate diff --env django` to automatically plan a migration from the current database version to the Django schema.
+
+### Installation
+
+Install Atlas for macOS or Linux by running:
+```bash
+curl -sSf https://atlasgo.sh | sh
+```
+
+See [atlasgo.io](https://atlasgo.io/getting-started#installation) for more installation options.
+
+Install the provider by running:
+
+```bash
+pip install altas-provider-django
+```
+
+### Configuration
+
+Add the provider to your Django project's `INSTALLED_APPS` in `settings.py`:
+
+```python
+INSTALLED_APPS = [
+    ...,
+    'altas_provider_django',
+    ...
+]
+```
+
+In your project directory, create a new file named `atlas.hcl` with the following contents:
+
+```hcl
+data "external_schema" "django" {
+  program = [
+    "python",
+    "manage.py",
+    "atlas-provider-django",
+    "--dialect", "mysql" // mariadb | postgresql | sqlite
+    // if you want to only load a subset of your app models, you can specify the apps by adding
+    // "--apps", "app1", "app2", "app3"
+  ]
+}
+
+env "django" {
+  src = data.external_schema.django.url
+  dev = "docker://mysql/8/dev"
+  migration {
+    dir = "file://migrations"
+  }
+  format {
+    migrate {
+      diff = "{{ sql . \"  \" }}"
+    }
+  }
+}
+```
+
+
+### Usage
+
+#### Apply
+
+You can use the `atlas schema apply` command to plan and apply a migration of your database to your current Django schema.
+This works by inspecting the target database and comparing it to the Django Apps models and creating a migration plan.
+Atlas will prompt you to confirm the migration plan before applying it to the database.
+
+```bash
+atlas schema apply --env django -u "mysql://root:password@localhost:3306/mydb"
+```
+Where the `-u` flag accepts the [URL](https://atlasgo.io/concepts/url) to the
+target database.
+
+#### Diff
+
+Atlas supports a [versioned migrations](https://atlasgo.io/concepts/declarative-vs-versioned#versioned-migrations) 
+workflow, where each change to the database is versioned and recorded in a migration file. You can use the
+`atlas migrate diff` command to automatically generate a migration file that will migrate the database
+from its latest revision to the current Django schema.
+
+```bash
+atlas migrate diff --env django 
+````
+
+### Supported Databases
+
+The provider supports the following databases:
+* MySQL
+* MariaDB
+* PostgreSQL
+* SQLite
+
+### Issues
+
+Please report any issues or feature requests in the [ariga/atlas](https://github.com/ariga/atlas/issues) repository.
+
+### License
+
+This project is licensed under the [Apache License 2.0](LICENSE).