Remove ZSTD and all references to it: closes #3134

CONTRIBUTING.md

@@ -92,7 +92,7 @@ Example:
 
 ```python
 @pytest.mark.parametrize(
-        "compress, compressScheme", [(True, "lz4"), (False, "lz4"), (True, "zstd"), (False, "zstd")]
+        "compress, compressScheme", [(True, "lz4"), (False, "lz4")]
     )
 def test_hooked_tensor(self, compress, compressScheme):
     TorchHook(torch)

README.md

@@ -10,7 +10,7 @@
 PySyft is a Python library for secure and private Deep Learning. PySyft decouples private data from model training, using
 [Federated Learning](https://ai.googleblog.com/2017/04/federated-learning-collaborative.html),
 [Differential Privacy](https://en.wikipedia.org/wiki/Differential_privacy),
-and Encrypted Computation (like 
+and Encrypted Computation (like
 [Multi-Party Computation (MPC)](https://en.wikipedia.org/wiki/Secure_multi-party_computation)
 and  [Homomorphic Encryption (HE)](https://en.wikipedia.org/wiki/Homomorphic_encryption))
 within the main Deep Learning frameworks like PyTorch and TensorFlow. Join the movement on
@@ -69,19 +69,6 @@ installation error related to PyTorch or TF Encrypted, please
 open an issue on Github or reach out to `#team_pysyft` in
 Slack.
 
-If you have an installation error regarding zstd, run this command and then re-try installing syft.
-
-```bash
-pip install --upgrade --force-reinstall zstd
-```
-If this still doesn't work, and you happen to be on OSX, make
-sure you have [OSX command line tools](https://railsapps.github.io/xcode-command-line-tools.html) installed and try again.
-
-If this still fails, and you are on a Conda environment. It could be
-because conda provides its own compiler and linker tools which might
-conflict with your system's. In that case we recommend to use a python venv
-and try again.
-
 You can also install PySyft from source on a variety of operating systems by following this [installation guide](https://github.com/OpenMined/PySyft/blob/dev/INSTALLATION.md).
 
 ## Run Local Notebook Server

pip-dep/requirements.txt

@@ -12,5 +12,4 @@ tblib~=1.6.0
 torchvision~=0.5.0
 torch~=1.4.0
 websocket_client~=0.57.0
-websockets~=8.1.0
-zstd~=1.4.4.0
+websockets~=8.1.0

syft/serde/compression.py

@@ -7,18 +7,15 @@
 from lz4 import (  # noqa: F401
     frame,
 )  # needed as otherwise we will get: module 'lz4' has no attribute 'frame'
-import zstd
 
 from syft.exceptions import CompressionNotFoundException
 
 # COMPRESSION SCHEME INT CODES
 NO_COMPRESSION = 40
 LZ4 = 41
-ZSTD = 42
 scheme_to_bytes = {
     NO_COMPRESSION: NO_COMPRESSION.to_bytes(1, byteorder="big"),
     LZ4: LZ4.to_bytes(1, byteorder="big"),
-    ZSTD: ZSTD.to_bytes(1, byteorder="big"),
 }
 
 ## SECTION: chosen Compression Algorithm
@@ -48,20 +45,6 @@ def apply_lz4_compression(decompressed_input_bin) -> tuple:
     return lz4.frame.compress(decompressed_input_bin), LZ4
 
 
-def apply_zstd_compression(decompressed_input_bin) -> tuple:
-    """
-    Apply ZSTD compression to the input
-
-    Args:
-        decompressed_input_bin: the binary to be compressed
-
-    Returns:
-        a tuple (compressed_result, ZSTD)
-    """
-
-    return zstd.compress(decompressed_input_bin), ZSTD
-
-
 def apply_no_compression(decompressed_input_bin) -> tuple:
     """
     No compression is applied to the input
@@ -118,8 +101,6 @@ def _decompress(binary: bin) -> bin:
     # 1)  Decompress or return the original stream
     if compress_scheme == LZ4:
         return lz4.frame.decompress(binary)
-    elif compress_scheme == ZSTD:
-        return zstd.decompress(binary)
     elif compress_scheme == NO_COMPRESSION:
         return binary
     else:

test/serde/msgpack/test_msgpack_serde.py

@@ -416,14 +416,10 @@ def test_ndarray_serde(compress):
     assert numpy.array_equal(arr, arr_serialized_deserialized)
 
 
-@pytest.mark.parametrize(
-    "compress_scheme", [compression.LZ4, compression.ZSTD, compression.NO_COMPRESSION]
-)
+@pytest.mark.parametrize("compress_scheme", [compression.LZ4, compression.NO_COMPRESSION])
 def test_compress_decompress(compress_scheme):
     if compress_scheme == compression.LZ4:
         compression._apply_compress_scheme = compression.apply_lz4_compression
-    elif compress_scheme == compression.ZSTD:
-        compression._apply_compress_scheme = compression.apply_zstd_compression
     else:
         compression._apply_compress_scheme = compression.apply_no_compression
 
@@ -434,14 +430,10 @@ def test_compress_decompress(compress_scheme):
     assert original == decompressed
 
 
-@pytest.mark.parametrize(
-    "compress_scheme", [compression.LZ4, compression.ZSTD, compression.NO_COMPRESSION]
-)
+@pytest.mark.parametrize("compress_scheme", [compression.LZ4, compression.NO_COMPRESSION])
 def test_compressed_serde(compress_scheme):
     if compress_scheme == compression.LZ4:
         compression._apply_compress_scheme = compression.apply_lz4_compression
-    elif compress_scheme == compression.ZSTD:
-        compression._apply_compress_scheme = compression.apply_zstd_compression
     else:
         compression._apply_compress_scheme = compression.apply_no_compression
 
@@ -626,8 +618,6 @@ def test_float(compress):
     [
         (True, compression.LZ4),
         (False, compression.LZ4),
-        (True, compression.ZSTD),
-        (False, compression.ZSTD),
         (True, compression.NO_COMPRESSION),
         (False, compression.NO_COMPRESSION),
     ],
@@ -636,8 +626,6 @@ def test_hooked_tensor(compress, compress_scheme):
     if compress:
         if compress_scheme == compression.LZ4:
             compression._apply_compress_scheme = compression.apply_lz4_compression
-        elif compress_scheme == compression.ZSTD:
-            compression._apply_compress_scheme = compression.apply_zstd_compression
         else:
             compression._apply_compress_scheme = compression.apply_no_compression
     else: