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README.md

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 # env2yaml
-Docker container for conversion of env files to YAML files to be used with Google Cloud Run gcloud CLI
+
+Docker container for conversion of env files to YAML files to be used with Google Cloud Run gcloud CLI. It is in particular design to be used with GitHub Actions et Google Cloud Build to deploy applications to Google Cloud Run.
+
+This container is loosely based after [this shell script](https://gist.github.com/l2D/51389881160b2bb9fdafc75277186b84) by [l2D](https://gist.github.com/l2D).
+
+## Usage
+
+As a standalone script:
+```bash
+curl -L -o env2yaml.sh https://raw.githubusercontent.com/joanfabregat/env2yaml/main/env2yaml.cjs 
+node env2yaml.sh .env env.yaml
+```
+
+In a [`cloudbuild.yaml`](https://cloud.google.com/build/docs/build-config-file-schema) configuration file:
+```yaml
+steps:
+  # Build the container image
+  - id: 'docker-build'
+    name: 'gcr.io/cloud-builders/docker'
+    args:
+      - 'build'
+      - '.'
+
+  # Generation of the env.yaml file
+  - id: 'env2yaml'
+    name: 'joanfabregat/env2yaml'
+    env:
+      - 'INPUT_FILE=/workspace/.env'
+      - 'OUTPUT_FILE=/workspace/.env.yaml'
+
+  # Deploy container image to Cloud Run
+  - id: 'deploy-to-cloudrun-staging'
+    name: 'gcr.io/google.com/cloudsdktool/cloud-sdk'
+    args:
+      - 'run'
+      - 'deploy'
+      - '--env-vars-file=/workspace/.env.yaml'
+```