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README.md

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+
+# K8sPolicy
+
+This cli-tool helps you to run rego-policies against your kubernetes yaml-files. Helm-Charts are supported as well. [Conftest](https://github.com/instrumenta/conftest) is used under the hood.
+
+## Installation
+
+Download the appropriate binary from the [releases](https://github.com/code-chris/k8spolicy/releases) page.
+
+## Usage
+```
+Run's all configured rules against the manifests to test
+
+Usage:
+  k8spolicy test [flags]
+
+Flags:
+  -h, --help                     help for test
+      --skip-conftest-download   Do not download the conftest binary
+      --skip-policy-download     Do not download the policy files
+
+Global Flags:
+      --config string   config file (default is .k8spolicy.yaml)
+```
+
+A configuration file is required. See below for details.
+
+### ENV
+
+The environment variables `K8SPOLICY_SKIP_POLICY_DOWNLOAD` and `K8SPOLICY_SKIP_CONFTEST_DOWNLOAD` can be set to `true` as cli-flag replacement.
+
+## Configuration
+```
+rules:
+  presets:
+    - k8s-api-deprecation
+    - k8s-security
+  additionals:
+    - files: path/to/my/policies/*.rego
+    - url: https://github.com/instrumenta/policies
+      files: kubernetes/**/*.rego
+targetVersion: 1.17
+helm:
+  repositories:
+    - url: https://charts.bitnami.com/bitnami
+      chart: nginx-ingress-controller
+      version: 5.3.13
+      values:
+        - charts/nginx-chart.yaml
+  registries:
+    - url: registry.mycompany.com/charts
+      version: 1.0.0
+      values:
+        - charts/myawesome-chart.yaml
+files:
+  - additional/manifest/files/*.yaml
+```
+All filesystem paths are relative to the execution directory of the cli-tool.
+
+#### rules.presets
+Use this array to automatically include one of these presets:
+| Name                 | URL                                     |
+| -------------------- | --------------------------------------- |
+| k8s-api-deprecation  | https://github.com/swade1987/deprek8ion |
+| k8s-security         | https://github.com/instrumenta/policies |
+
+#### rules.additionals
+If only files are specified, this is determined as local path. If a url is also given, then the files are downloaded. It is assumed, that the download-url resolves to a `tar.gz` file. In case of a `github.com` (as above) the current master-tarball is used. Only the given filepath is used from the downloaded files.
+
+#### targetVersion (optional)
+If a rego-file includes a kubernetes-version (this regex is used: `.*(\d\.\d+).*\.rego`) you can exclude those files which have a greater version.
+
+#### helm.repositories
+A list of charts from repositories to validate. `url` and `chart` are mandatory, `version` and `values` are optional.
+
+#### helm.registries
+A list of charts from OCI-Registries to validate. `url` and `version` are mandatory, `values` are optional.
+
+#### files
+A list of any other local yaml-files which should be validated.
+
+
+You have to use a preset or specify any additional rules. One of the `helm.repositories`, `helm.registries` or `files` is also mandatory.
+
+
+## Docker
+
+There's a docker-image for usage in CI-Environemnts for example.
+```
+docker pull ckotzbauer/k8spolicy
+```
+
+The image is pre-populated with the `conftest` binary and the two presets. The download of both is disabled by default.
+
+
+## Roadmap
+
+- Support helm-registries with authentication.
+- Filter results with a regex.