Read Native Query SQL from files

changelog.md

@@ -2,6 +2,11 @@
 
 ## [Unreleased]
 
+### Added
+
+- Support for reading Native Query SQL from files.
+  ([#372](https://github.com/hasura/ndc-postgres/pull/372))
+
 ### Changed
 
 - Do not print information about when the cli decides not to write to a file.

crates/configuration/src/configuration.rs

@@ -60,14 +60,29 @@ pub async fn parse_configuration(
     environment: impl Environment,
 ) -> Result<Configuration, Error> {
     let configuration_file = configuration_dir.as_ref().join(CONFIGURATION_FILENAME);
-    let configuration_file_contents = fs::read_to_string(&configuration_file).await?;
-    let configuration: version3::RawConfiguration =
+
+    let configuration_file_contents =
+        fs::read_to_string(&configuration_file)
+            .await
+            .map_err(|err| {
+                Error::IoErrorButStringified(format!("{}: {}", &configuration_file.display(), err))
+            })?;
+    let mut configuration: version3::RawConfiguration =
         serde_json::from_str(&configuration_file_contents).map_err(|error| Error::ParseError {
             file_path: configuration_file.clone(),
             line: error.line(),
             column: error.column(),
             message: error.to_string(),
         })?;
+    // look for native query sql file references and read from disk.
+    for native_query_sql in configuration.metadata.native_queries.0.values_mut() {
+        native_query_sql.sql = metadata::NativeQuerySqlEither::NativeQuerySql(
+            native_query_sql
+                .sql
+                .from_external(configuration_dir.as_ref())
+                .map_err(Error::IoErrorButStringified)?,
+        );
+    }
     let connection_uri =
         match configuration.connection_settings.connection_uri {
             ConnectionUri(Secret::Plain(uri)) => Ok(uri),

crates/configuration/src/error.rs

@@ -21,6 +21,10 @@ pub enum Error {
         file_path: std::path::PathBuf,
         message: String,
     },
+
+    #[error("I/O error: {0}")]
+    IoErrorButStringified(String),
+
     #[error("I/O error: {0}")]
     IoError(#[from] std::io::Error),
 }

crates/connectors/ndc-postgres/src/connector.rs

@@ -253,6 +253,9 @@ impl<Env: Environment + Send + Sync> ConnectorSetup for PostgresSetup<Env> {
                     ]))
                 }
                 configuration::Error::IoError(inner) => connector::ParseError::IoError(inner),
+                configuration::Error::IoErrorButStringified(inner) => {
+                    connector::ParseError::Other(inner.into())
+                }
             })
 
         // Note that we don't log validation errors, because they are part of the normal business

crates/query-engine/metadata/Cargo.toml

@@ -10,3 +10,6 @@ workspace = true
 [dependencies]
 schemars = { version = "0.8.16", features = ["smol_str"] }
 serde = { version = "1.0.197", features = ["derive"] }
+
+[dev-dependencies]
+serde_json = "1.0.114"