Add contributing guidelines (#59)

* Contributing guidelines - pass 1

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CONTRIBUTING.md

@@ -0,0 +1,53 @@
+<div align="center" style="padding-bottom: 1em;">
+<img width="100px" align="center" src="https://avatars.githubusercontent.com/u/74017645?s=200&v=4">
+</div>
+
+# <div align="center">MaRDA Metadata Extractors: Registry</div>
+## <div align="center">Contributing guidelines</div>
+
+Contributions to this registry are welcome. We pledge to follow the [Contributor Covenant Code of Conduct](https://www.contributor-covenant.org/version/2/1/code_of_conduct/).
+
+You can contribute `FileType` and `Extractor` entries to this registry by creating pull requests (PRs), which should include YAML files under `./data/filetypes` and `./data/extractors`, respectively. These YAML files  must follow the schemas at [marda-alliance/metadata_extractors_schema](https://github.com/marda-alliance/metadata_extractors_schema) (see the [online documentation](https://marda-alliance.github.io/metadata_extractors_schema) for more details).
+
+An example of the process can be seen in this [pull request](https://github.com/marda-alliance/metadata_extractors_registry/pull/54). The workflow steps are as follows:
+
+
+### Opening a pull request
+- One pull request (PR) per `Extractor`, please.
+    - You can include multiple versions of one `Extractor` in separate `.yml` files.
+    - Do not include multiple unrelated `Extractors` in a single PR.
+- Include any missing `FileTypes` supported by the `Extractor` in the same PR.
+- Please add the appropriate labels (`Extractor` and `FileType`).
+
+### Example files
+- If you are adding new `FileTypes` in this PR, add example files of those `FileTypes` using `git-lfs` into `marda_registry/data/lfs`. Do not commit example files into the repository directly. For example, to add a new file called `xmpl.tpe` (corresponding to the `FileType` with ID `example-type`) you would:
+
+  ``` bash
+    mkdir marda_registry/data/lfs/example-type  # create the dir using FileType ID
+    cp xmpl.tpe marda_registry/data/lfs/example-type  # copy the example file
+    git lfs install  # setup git-lfs, only necessary if you haven't used git-lfs before
+    git add marda_registry/data/lfs/example-type/*  # track files
+    ...
+    git lfs ls-files  # check that your new example files are tracked before committing
+    git commit
+    git push
+  ```
+
+### Validation of Definitions
+- Your PR will have to pass the testing using our continuous integration (CI) set-up. The CI checks the following three things:
+    - `lint`, making sure the `yml` files you added are properly formatted,
+    - `validate`, which validates the `yml` files against their schemas, and
+    - `build`, which makes sure the new registry website can be built.
+
+  Therefore, it is mainly the `lint` and `validate` actions you will have to pay attention to. In case anything is unclear or you cannot find the error, ping one of the [Registry Maintainers](./README.md#registry-maintainers).
+- You can of course validate your definitions locally, by using the [![Schema](https://badgen.net/static/marda-alliance/metadata_extractors_schema/?icon=github)](https://github.com/marda-alliance/metadata_extractors_schema/) package, see the [Usage section](https://marda-alliance.github.io/metadata_extractors_schema/main/usage.html) of the documentation.
+
+### Testing of Extraction
+- You should check that your `yml` definitions can be used to install the `Extractor` and and extract any example files from the supported `FileTypes` locally, by using our [![Schema](https://badgen.net/static/marda-alliance/metadata_extractors_api/?icon=github)](https://github.com/marda-alliance/metadata_extractors_api/) package, see the [Installation](https://github.com/marda-alliance/metadata_extractors_api#installation) and [Usage](https://github.com/marda-alliance/metadata_extractors_api#usage) sections.
+
+> At the moment, the above CI is not checking whether the extraction of the example files actually works. See [this issue](https://github.com/marda-alliance/metadata_extractors_registry/issues/34) for further details.
+
+### Approval and Deployment
+- If you are a first-time contributor to the project, we will need to pre-approve your PR so that the CI can be run. Ping one of the [Registry Maintainers](./README.md#registry-maintainers).
+- Once the CI passes, and all issues that are raised during the review are addressed, your PR can be merged.
+- Once your PR is merged into the Registry, your new definitions should be available at the [Registry Website](https://marda-registry.fly.dev/). Cheers!

README.md

@@ -21,9 +21,7 @@ The state of the `main` branch is deployed to https://marda-registry.fly.dev/, w
 
 ## Contributing
 
-You can contribute file type and extractor entries to this registry by creating YAML files under `./data/filetypes` and `./data/extractors`, following the schemas at [marda-alliance/metadata_extractors_schema](https://github.com/marda-alliance/metadata_extractors_schema) ([online documentation](https://marda-alliance.github.io/metadata_extractors_schema)].
-
-After submitting a pull request, this data will be validated and added to the deployed database once it is merged.
+You are welcome to contribute file type and extractor entries to this registry, by opening a pull request. Please see the [contributing guidelines](./CONTRIBUTING.md) for detailed steps. After submitting a pull request, this data will be validated and added to the deployed database once it is merged.
 
 ## Development
 
@@ -65,3 +63,7 @@ docker run -p 8080 --env PORT=8080 marda-registry
 ```
 
 or equivalent command.
+
+## Registry Maintainers
+- Matthew Evans, [@ml-evs](https://github.com/ml-evs)
+- Peter Kraus, [@PeterKraus](https://github.com/PeterKraus)

marda_registry/templates/index.html

@@ -17,7 +17,7 @@
 
 <h2>Contributing</h2>
 
-<p>Anyone can contribute file type and extractor entries to this registry by following the instructions in the <a href="https://github.com/marda-alliance/metadata_extractors_registry">README on <i class="fa fa-github"></i> GitHub</a>.</p>
+<p>Anyone can contribute file type and extractor entries to this registry by following the instructions in the <a href="https://github.com/marda-alliance/metadata_extractors_registry/blob/main/CONTRIBUTING.md">contributing guidelines on <i class="fa fa-github"></i> GitHub</a>.</p>
 <p>After submitting a pull request, this data will be validated and added to the deployed database once it is merged.</p>