Add from_private_key_der and from_private_key_pem to PyKeyPair

Cargo.toml

@@ -8,7 +8,7 @@ name = "biscuit_auth"
 crate-type = ["cdylib"]
 
 [dependencies]
-biscuit-auth = "4.0.0"
+biscuit-auth = { version = "4.1.1", features = ["pem"] }
 pyo3 = { version = "0.18.3", features = ["extension-module", "chrono"]}
 hex = "0.4"
 base64 = "0.13.0"

biscuit_auth.pyi

@@ -372,6 +372,23 @@ class KeyPair:
     @classmethod
     def from_private_key(cls, private_key: PrivateKey) -> KeyPair: ...
 
+    # Generate a keypair from a DER buffer
+    #
+    # :param bytes: private key bytes in DER format
+    # :type private_key: PrivateKey
+    # :return: the corresponding keypair
+    # :rtype: KeyPair
+    @classmethod
+    def from_private_key_der(cls, der: bytes) -> KeyPair: ...
+
+    #
+    # :param bytes: private key bytes in PEM format
+    # :type private_key: PrivateKey
+    # :return: the corresponding keypair
+    # :rtype: KeyPair
+    @classmethod
+    def from_private_key_pem(cls, pem: str) -> KeyPair: ...
+
     # The public key part
     @property
     def public_key(self) -> PublicKey: ...

biscuit_test.py

@@ -4,7 +4,7 @@
 
 import pytest
 
-from biscuit_auth import Authorizer, Biscuit, BiscuitBuilder, BlockBuilder, Check, Fact, KeyPair, Policy, PrivateKey, PublicKey, Rule, UnverifiedBiscuit
+from biscuit_auth import KeyPair,Authorizer, Biscuit, BiscuitBuilder, BlockBuilder, Check, Fact, KeyPair, Policy, PrivateKey, PublicKey, Rule, UnverifiedBiscuit
 
 def test_fact():
     fact = Fact('fact(1, true, "", "Test", hex:aabbcc, 2023-04-29T01:00:00Z)')
@@ -418,3 +418,17 @@ def test_append_on_unverified():
 
     utoken2 = utoken.append(BlockBuilder("check if true"))
     assert utoken2.block_source(3) == "check if true;\n"
+
+
+def test_keypair_from_private_key_der():
+    private_key_der = bytes.fromhex("302e020100300506032b6570042204200499694d0da05dcac40052663e71d50c1539465f8926dfe92033cf7aaad53d65")
+    private_key_hex = "0499694d0da05dcac40052663e71d50c1539465f8926dfe92033cf7aaad53d65"
+    kp = KeyPair.from_private_key_der(der=private_key_der)
+    assert kp.private_key.to_hex() == private_key_hex
+
+
+def test_keypair_from_private_key_pem():
+    private_key_pem = "-----BEGIN PRIVATE KEY-----\nMC4CAQAwBQYDK2VwBCIEIASZaU0NoF3KxABSZj5x1QwVOUZfiSbf6SAzz3qq1T1l\n-----END PRIVATE KEY-----"
+    private_key_hex = "0499694d0da05dcac40052663e71d50c1539465f8926dfe92033cf7aaad53d65"
+    kp = KeyPair.from_private_key_pem(pem=private_key_pem)
+    assert kp.private_key.to_hex() == private_key_hex

src/lib.rs

@@ -701,6 +701,32 @@ impl PyKeyPair {
         PyKeyPair(KeyPair::from(&private_key.0))
     }
 
+    /// Generate a keypair from a DER buffer
+    ///
+    /// :param bytes: private key bytes in DER format
+    /// :type private_key: PrivateKey
+    /// :return: the corresponding keypair
+    /// :rtype: KeyPair
+    #[classmethod]
+    pub fn from_private_key_der(_: &PyType, der: &[u8]) -> PyResult<Self> {
+        let kp = KeyPair::from_private_key_der(der)
+            .map_err(|e: error::Format| pyo3::exceptions::PyValueError::new_err(e.to_string()))?;
+        Ok(PyKeyPair(kp))
+    }
+
+    /// Generate a keypair from a PEM buffer
+    ///
+    /// :param bytes: private key bytes in PEM format
+    /// :type private_key: PrivateKey
+    /// :return: the corresponding keypair
+    /// :rtype: KeyPair
+    #[classmethod]
+    pub fn from_private_key_pem(_: &PyType, pem: &str) -> PyResult<Self> {
+        let kp = KeyPair::from_private_key_pem(pem)
+            .map_err(|e: error::Format| pyo3::exceptions::PyValueError::new_err(e.to_string()))?;
+        Ok(PyKeyPair(kp))
+    }
+
     /// The public key part
     #[getter]
     pub fn public_key(&self) -> PyPublicKey {