return an empty result when geolocation data is not found (#341)

lib/src/error.rs

@@ -92,9 +92,6 @@ pub enum Error {
     #[error(transparent)]
     DeviceDetectionError(#[from] crate::wiggle_abi::DeviceDetectionError),
 
-    #[error(transparent)]
-    GeolocationError(#[from] crate::wiggle_abi::GeolocationError),
-
     #[error(transparent)]
     ObjectStoreError(#[from] crate::object_store::ObjectStoreError),
 
@@ -184,7 +181,6 @@ impl Error {
             // We delegate to some error types' own implementation of `to_fastly_status`.
             Error::DictionaryError(e) => e.to_fastly_status(),
             Error::DeviceDetectionError(e) => e.to_fastly_status(),
-            Error::GeolocationError(e) => e.to_fastly_status(),
             Error::ObjectStoreError(e) => e.into(),
             Error::SecretStoreError(e) => e.into(),
             Error::Again => FastlyStatus::Again,

lib/src/wiggle_abi.rs

@@ -14,7 +14,6 @@ pub use self::dictionary_impl::DictionaryError;
 pub use self::secret_store_impl::SecretStoreError;
 
 pub use self::device_detection_impl::DeviceDetectionError;
-pub use self::geo_impl::GeolocationError;
 
 use {
     self::{

lib/src/wiggle_abi/geo_impl.rs

@@ -6,32 +6,11 @@ use std::{
 };
 
 use {
-    crate::{
-        error::Error,
-        session::Session,
-        wiggle_abi::{fastly_geo::FastlyGeo, types::FastlyStatus},
-    },
+    crate::{error::Error, session::Session, wiggle_abi::fastly_geo::FastlyGeo},
     std::convert::TryFrom,
     wiggle::GuestPtr,
 };
 
-#[derive(Debug, thiserror::Error)]
-pub enum GeolocationError {
-    /// Geolocation data for given address not found.
-    #[error("No geolocation data: {0}")]
-    NoGeolocationData(String),
-}
-
-impl GeolocationError {
-    /// Convert to an error code representation suitable for passing across the ABI boundary.
-    pub fn to_fastly_status(&self) -> FastlyStatus {
-        use GeolocationError::*;
-        match self {
-            NoGeolocationData(_) => FastlyStatus::None,
-        }
-    }
-}
-
 impl FastlyGeo for Session {
     fn lookup(
         &mut self,
@@ -57,9 +36,7 @@ impl FastlyGeo for Session {
             _ => return Err(Error::InvalidArgument),
         };
 
-        let result = self
-            .geolocation_lookup(&ip_addr)
-            .ok_or_else(|| GeolocationError::NoGeolocationData(ip_addr.to_string()))?;
+        let result = self.geolocation_lookup(&ip_addr).unwrap_or_default();
 
         if result.len() > buf_len as usize {
             return Err(Error::BufferLengthError {