python/examples/hybrid/README.md

# Python hybrid encryption example

This example shows how to encrypt data with Tink using hybrid encryption.

It demonstrates the basic steps of using Tink, namely loading key material,
obtaining a primitive, and using the primitive to do crypto.

The key material was generated with Tinkey:

```shell
$ tinkey create-keyset \
    --key-template DHKEM_X25519_HKDF_SHA256_HKDF_SHA256_AES_256_GCM \
    --out-format JSON --out hybrid_test_private_keyset.json

$ tinkey create-public-keyset --in hybrid_test_private_keyset.json \
    --in-format JSON --out-format JSON --out hybrid_test_public_keyset.json
```

## Build and Run

### Bazel

```shell
$ git clone https://github.com/google/tink
$ cd tink/python/examples
$ bazel build ...
```

You can then encrypt a file:

```shell
$ echo "some data" > testdata.txt
$ ./bazel-bin/hybrid/hybrid_cli --mode encrypt \
    --keyset_path ./hybrid/hybrid_test_public_keyset.json \
    --input_path testdata.txt --output_path testdata.txt.encrypted
```

Or decrypt the file with:

```shell
$ ./bazel-bin/hybrid/hybrid_cli --mode decrypt \
    --keyset_path ./hybrid/hybrid_test_private_keyset.json \
    --input_path testdata.txt.encrypted --output_path testdata.txt.decrypted
$ diff testdata.txt testdata.txt.decrypted
```