fix issue 120: DecodingKey can be converted to static

src/decoding.rs

@@ -34,7 +34,7 @@ macro_rules! expect_two {
 #[derive(Debug, Clone, PartialEq)]
 pub(crate) enum DecodingKeyKind<'a> {
     SecretOrDer(Cow<'a, [u8]>),
-    RsaModulusExponent { n: &'a str, e: &'a str },
+    RsaModulusExponent { n: Cow<'a, str>, e: Cow<'a, str> },
 }
 
 /// All the different kind of keys we can use to decode a JWT
@@ -54,43 +54,17 @@ impl<'a> DecodingKey<'a> {
         }
     }
 
-    /// If you're using HMAC with a base64 encoded, use this.
-    pub fn from_base64_secret(secret: &str) -> Result<Self> {
-        let out = base64::decode(&secret)?;
-        Ok(DecodingKey {
-            family: AlgorithmFamily::Hmac,
-            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(out)),
-        })
-    }
-
-    /// If you are loading a public RSA key in a PEM format, use this.
-    pub fn from_rsa_pem(key: &'a [u8]) -> Result<Self> {
-        let pem_key = PemEncodedKey::new(key)?;
-        let content = pem_key.as_rsa_key()?;
-        Ok(DecodingKey {
-            family: AlgorithmFamily::Rsa,
-            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
-        })
-    }
-
     /// If you have (n, e) RSA public key components, use this.
     pub fn from_rsa_components(modulus: &'a str, exponent: &'a str) -> Self {
         DecodingKey {
             family: AlgorithmFamily::Rsa,
-            kind: DecodingKeyKind::RsaModulusExponent { n: modulus, e: exponent },
+            kind: DecodingKeyKind::RsaModulusExponent {
+                n: Cow::Borrowed(modulus),
+                e: Cow::Borrowed(exponent),
+            },
         }
     }
 
-    /// If you have a ECDSA public key in PEM format, use this.
-    pub fn from_ec_pem(key: &'a [u8]) -> Result<Self> {
-        let pem_key = PemEncodedKey::new(key)?;
-        let content = pem_key.as_ec_public_key()?;
-        Ok(DecodingKey {
-            family: AlgorithmFamily::Ec,
-            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
-        })
-    }
-
     /// If you know what you're doing and have a RSA DER encoded public key, use this.
     pub fn from_rsa_der(der: &'a [u8]) -> Self {
         DecodingKey {
@@ -107,6 +81,19 @@ impl<'a> DecodingKey<'a> {
         }
     }
 
+    /// Convert self to `DecodingKey<'static>`.
+    pub fn into_static(self) -> DecodingKey<'static> {
+        use DecodingKeyKind::*;
+        let DecodingKey { family, kind } = self;
+        let static_kind = match kind {
+            SecretOrDer(key) => SecretOrDer(Cow::Owned(key.into_owned())),
+            RsaModulusExponent { n, e } => {
+                RsaModulusExponent { n: Cow::Owned(n.into_owned()), e: Cow::Owned(e.into_owned()) }
+            }
+        };
+        DecodingKey { family, kind: static_kind }
+    }
+
     pub(crate) fn as_bytes(&self) -> &[u8] {
         match &self.kind {
             DecodingKeyKind::SecretOrDer(b) => &b,
@@ -115,6 +102,37 @@ impl<'a> DecodingKey<'a> {
     }
 }
 
+impl DecodingKey<'static> {
+    /// If you're using HMAC with a base64 encoded, use this.
+    pub fn from_base64_secret(secret: &str) -> Result<Self> {
+        let out = base64::decode(&secret)?;
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Hmac,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(out)),
+        })
+    }
+
+    /// If you are loading a public RSA key in a PEM format, use this.
+    pub fn from_rsa_pem(key: &[u8]) -> Result<Self> {
+        let pem_key = PemEncodedKey::new(key)?;
+        let content = pem_key.as_rsa_key()?;
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Rsa,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
+        })
+    }
+
+    /// If you have a ECDSA public key in PEM format, use this.
+    pub fn from_ec_pem(key: &[u8]) -> Result<Self> {
+        let pem_key = PemEncodedKey::new(key)?;
+        let content = pem_key.as_ec_public_key()?;
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Ec,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
+        })
+    }
+}
+
 /// Decode and validate a JWT
 ///
 /// If the token or its signature is invalid or the claims fail validation, it will return an error.

src/errors.rs

@@ -169,7 +169,9 @@ mod tests {
 
     #[test]
     fn test_error_rendering() {
-        assert_eq!("InvalidAlgorithmName", Error::from(ErrorKind::InvalidAlgorithmName).to_string());
+        assert_eq!(
+            "InvalidAlgorithmName",
+            Error::from(ErrorKind::InvalidAlgorithmName).to_string()
+        );
     }
-
-}
+}