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README.md

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+# concourse-oci-resource
+
+A resource type for oci image tarballs.
+
+## Source configuration
+
+```yaml
+resource_types:
+- name: oci-image
+  type: registry-image
+  source:
+    repository: redxef/concourse-oci-resource
+resources:
+- name: my-image
+  type: oci-image
+  source:
+    repository: redxef/concourse-oci-resource
+    tag: latest
+    username: ((registry.username))
+    password: ((registry.password))
+```
+
+- repository: *Required*. The URI of the image repository.
+- tag: *Optional*. *Default* `latest`. The tag of this image.
+- username: *Optional*. Username used to authenticate.
+- password: *Optional*. Password used to authenticate.
+
+## `check`
+
+Check if there is a new version represented with the given source
+configuration.
+
+## `in` receive a OCI tarball
+
+Creates the following files:
+
+- `./image.tar`: The image tarball.
+- `./digest`: A file containing the digest of the pulled image.
+- `./repository`: The repository name (the same as the source configuration).
+
+## `out` push an image to a repository
+
+Push the image to the repository and add tags.
+
+### Configuration
+
+```yaml
+- put: my-image
+  params:
+    additional_tags: path/to/tags/file
+```
+
+### Parameters
+
+- additional\_tags: *Optional*. The path to a file containing more tags.
+