Merge pull request #174 from cipherstash/error-message-internal-error

feat: improve error message for internal errors

Author: yujiyokoo

docs/errors.md

@@ -12,6 +12,7 @@
   - [Invalid parameter](#mapping-invalid-parameter)
   - [Invalid SQL statement](#mapping-invalid-sql-statement)
   - [Unsupported parameter type](#mapping-unsupported-parameter-type)
+  - [Internal Error](#mapping-internal-error)
 
 - Encrypt Errors:
   - [Column could not be encrypted](#encrypt-column-could-not-be-encrypted)
@@ -164,6 +165,28 @@ Check the supported types for encrypted columns.
 
 
 
+<!-- ---------------------------------------------------------------------------------------------------- -->
+
+
+## Internal Mapper error <a id='mapping-internal-error'></a>
+
+An internal error occurred when attempting to rewrite the SQL statement.
+This could be due to an internal invariant failure or because of a specific fragment of unsupported SQL syntax.
+
+### Error message
+
+```
+Statement encountered an internal error. This may be a bug in the statement mapping module of CipherStash Proxy.
+```
+
+### How to Fix
+
+If you are running an older version of CipherStash Proxy, please update to the latest version.
+
+If the error persists, please contact CipherStash [support](https://cipherstash.com/support).
+
+
+
 <!-- ---------------------------------------------------------------------------------------------------- -->
 
 

packages/cipherstash-proxy-integration/src/extended_protocol_error_messages.rs

@@ -66,7 +66,7 @@ mod tests {
         if let Err(err) = result {
             let msg = err.to_string();
 
-            assert_eq!(msg, "db error: ERROR: Column 'encrypted_unconfigured' in table 'unconfigured' has no Encrypt configuration. For help visit https://github.com/cipherstash/proxy/docs/errors.md#encrypt-unknown-column");
+            assert_eq!(msg, "db error: ERROR: Column 'encrypted_unconfigured' in table 'unconfigured' has no Encrypt configuration. For help visit https://github.com/cipherstash/proxy/blob/main/docs/errors.md#encrypt-unknown-column");
         } else {
             unreachable!();
         }
@@ -122,7 +122,7 @@ mod tests {
         if let Err(err) = result {
             let msg = err.to_string();
             info!("{}", msg);
-            assert_eq!(msg, "db error: ERROR: sql parser error: Expected: SELECT, VALUES, or a subquery in the query body, found: id at Line: 1, Column: 23. For help visit https://github.com/cipherstash/proxy/docs/errors.md#mapping-invalid-sql-statement");
+            assert_eq!(msg, "db error: ERROR: sql parser error: Expected: SELECT, VALUES, or a subquery in the query body, found: id at Line: 1, Column: 23. For help visit https://github.com/cipherstash/proxy/blob/main/docs/errors.md#mapping-invalid-sql-statement");
         } else {
             unreachable!();
         }

packages/cipherstash-proxy/src/error.rs

@@ -6,7 +6,7 @@ use std::io;
 use thiserror::Error;
 use tokio::time::error::Elapsed;
 
-const ERROR_DOC_BASE_URL: &str = "https://github.com/cipherstash/proxy/docs/errors.md";
+const ERROR_DOC_BASE_URL: &str = "https://github.com/cipherstash/proxy/blob/main/docs/errors.md";
 
 #[derive(Error, Debug)]
 pub enum Error {
@@ -89,6 +89,9 @@ pub enum MappingError {
 
     #[error("Could not parse parameter")]
     CouldNotParseParameter,
+
+    #[error("Statement encountered an internal error. This may be a bug in the statement mapping module of CipherStash Proxy. Please visit {}#mapping-internal-error for more information.", ERROR_DOC_BASE_URL)]
+    Internal(String),
 }
 
 #[derive(Error, Debug)]
@@ -304,3 +307,16 @@ impl From<chrono::ParseError> for Error {
         MappingError::CouldNotParseParameter.into()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_internal_error_message() {
+        let error = MappingError::Internal("unexpected bug encounterd".to_string());
+        let message = error.to_string();
+
+        assert_eq!(format!("Statement encountered an internal error. This may be a bug in the statement mapping module of CipherStash Proxy. Please visit {}#mapping-internal-error for more information.", ERROR_DOC_BASE_URL), message);
+    }
+}

packages/cipherstash-proxy/src/postgresql/frontend.rs

@@ -25,7 +25,7 @@ use crate::prometheus::{
 use crate::Encrypted;
 use bytes::BytesMut;
 use cipherstash_client::encryption::Plaintext;
-use eql_mapper::{self, EqlValue, NodeKey, TableColumn, TypedStatement};
+use eql_mapper::{self, EqlMapperError, EqlValue, NodeKey, TableColumn, TypedStatement};
 use metrics::{counter, histogram};
 use pg_escape::quote_literal;
 use serde::Serialize;
@@ -737,6 +737,16 @@ where
 
                 Ok(typed_statement)
             }
+            Err(EqlMapperError::InternalError(str)) => {
+                warn!(
+                    client_id = self.context.client_id,
+                    msg = "Internal Error in EQL Mapper",
+                    mapping_errors_enabled = self.encrypt.config.mapping_errors_enabled(),
+                    error = str,
+                );
+                counter!(STATEMENTS_UNMAPPABLE_TOTAL).increment(1);
+                Err(MappingError::Internal(str).into())
+            }
             Err(err) => {
                 warn!(
                     client_id = self.context.client_id,