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README.md

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-# django-migration-checker-action
-Github actions for django app migrations checker
+django-migration-checker-action
+===========
+Github actions for django app migrations checker. To fix multiple develop commit 
+django migration in different Pull Request at the same time, and then cause 
+conflict migration issue.
+
+## Detail
+Use python package [django-migration-checker](https://github.com/tonyo/django-migration-checker) 
+to do migration validation. The package will not install any django related package. 
+Check migration by read file, not python import. So may not perfect solution, but good enough.
+
+
+## Usage
+
+Workflow example:
+```
+name: Django Migration Checker
+on: pull_request
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout the latest code
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 1
+
+      - name: Django Migration Checker
+        uses: hardcoretech/django-migration-checker-action@v1
+        with:
+          app-path: app
+```
+
+#### parameter
+inputs
+* `app-path`: django app folder path. after `action/checkout`, the working dir would be repository root.
+
+
+## Resource
+* Docker Hub - [django-migration-checker](https://hub.docker.com/r/hardcoretech/django-migration-checker)
+* Github - python package - [django-migration-checker](https://github.com/tonyo/django-migration-checker)
+