😯 Add support for the new secret from_bytes extension.

lib/compute-at-edge-abi/compute-at-edge.witx

@@ -555,6 +555,12 @@
         (param $nwritten_out (@witx pointer (@witx usize)))
         (result $err (expected (error $fastly_status)))
     )
+
+    (@interface func (export "from_bytes")
+        (param $buf (@witx pointer (@witx char8)))
+        (param $buf_len (@witx usize))
+        (result $err (expected $secret_handle (error $fastly_status)))
+    )
 )
 
 (module $fastly_backend

lib/src/secret_store.rs

@@ -53,8 +53,13 @@ impl Secret {
     }
 }
 
-#[derive(Clone, Debug, Default)]
-pub struct SecretLookup {
-    pub store_name: String,
-    pub secret_name: String,
+#[derive(Clone, Debug)]
+pub enum SecretLookup {
+    Standard {
+        store_name: String,
+        secret_name: String,
+    },
+    Injected {
+        plaintext: Vec<u8>,
+    },
 }

lib/src/session.rs

@@ -697,7 +697,7 @@ impl Session {
         self.secret_stores
             .get_store(store_name)?
             .get_secret(secret_name)?;
-        Some(self.secrets_by_name.push(SecretLookup {
+        Some(self.secrets_by_name.push(SecretLookup::Standard {
             store_name: store_name.to_string(),
             secret_name: secret_name.to_string(),
         }))
@@ -707,6 +707,11 @@ impl Session {
         self.secrets_by_name.get(handle).cloned()
     }
 
+    pub fn add_secret(&mut self, plaintext: Vec<u8>) -> SecretHandle {
+        self.secrets_by_name
+            .push(SecretLookup::Injected { plaintext })
+    }
+
     pub fn secret_stores(&self) -> &Arc<SecretStores> {
         &self.secret_stores
     }

lib/src/wiggle_abi/secret_store_impl.rs

@@ -1,6 +1,7 @@
 use {
     crate::{
         error::Error,
+        secret_store::SecretLookup,
         session::Session,
         wiggle_abi::{
             fastly_secret_store::FastlySecretStore,
@@ -81,17 +82,25 @@ impl FastlySecretStore for Session {
             .ok_or(Error::SecretStoreError(
                 SecretStoreError::InvalidSecretHandle(secret_handle),
             ))?;
-        let plaintext = self
-            .secret_stores()
-            .get_store(lookup.store_name.as_str())
-            .ok_or(Error::SecretStoreError(
-                SecretStoreError::InvalidSecretHandle(secret_handle),
-            ))?
-            .get_secret(lookup.secret_name.as_str())
-            .ok_or(Error::SecretStoreError(
-                SecretStoreError::InvalidSecretHandle(secret_handle),
-            ))?
-            .plaintext();
+
+        let plaintext = match &lookup {
+            SecretLookup::Standard {
+                store_name,
+                secret_name,
+            } => self
+                .secret_stores()
+                .get_store(store_name)
+                .ok_or(Error::SecretStoreError(
+                    SecretStoreError::InvalidSecretHandle(secret_handle),
+                ))?
+                .get_secret(secret_name)
+                .ok_or(Error::SecretStoreError(
+                    SecretStoreError::InvalidSecretHandle(secret_handle),
+                ))?
+                .plaintext(),
+
+            SecretLookup::Injected { plaintext } => plaintext,
+        };
 
         if plaintext.len() > plaintext_max_len as usize {
             // Write out the number of bytes necessary to fit the
@@ -115,4 +124,17 @@ impl FastlySecretStore for Session {
 
         Ok(())
     }
+
+    fn from_bytes(
+        &mut self,
+        plaintext_buf: &GuestPtr<'_, u8>,
+        plaintext_len: u32,
+    ) -> Result<SecretHandle, Error> {
+        let plaintext = plaintext_buf
+            .as_array(plaintext_len)
+            .as_slice()?
+            .ok_or(Error::SharedMemory)?
+            .to_vec();
+        Ok(self.add_secret(plaintext))
+    }
 }

test-fixtures/src/bin/secret-store.rs

@@ -1,6 +1,7 @@
 //! A guest program to test that secret store works properly.
 
 use fastly::SecretStore;
+use fastly::secret_store::Secret;
 
 fn main() {
     // Check we can't get a store that does not exist
@@ -20,4 +21,9 @@ fn main() {
         None => {}
         _ => panic!(),
     }
+
+    // FIXME: uncomment this when we release this API more fully
+    //let hello_bytes = "hello, wasm_world!".as_bytes().to_vec();
+    //let secret = Secret::from_bytes(hello_bytes).unwrap();
+    //assert_eq!("hello, wasm_world!", secret.plaintext());
 }