test (datafusion): add test for table provider creation (apache#651)

* add test for table provider creation

* fix formatting

* fixing yet another formatting issue

* testing schema using data fusion

---------

Co-authored-by: Alon Agmon <[email protected]>

crates/integrations/datafusion/src/table.rs

@@ -110,3 +110,57 @@ impl TableProvider for IcebergTableProvider {
         Ok(filter_support)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use datafusion::common::Column;
+    use datafusion::prelude::SessionContext;
+    use iceberg::io::FileIO;
+    use iceberg::table::{StaticTable, Table};
+    use iceberg::TableIdent;
+
+    use super::*;
+
+    async fn get_test_table_from_metadata_file() -> Table {
+        let metadata_file_name = "TableMetadataV2Valid.json";
+        let metadata_file_path = format!(
+            "{}/tests/test_data/{}",
+            env!("CARGO_MANIFEST_DIR"),
+            metadata_file_name
+        );
+        let file_io = FileIO::from_path(&metadata_file_path)
+            .unwrap()
+            .build()
+            .unwrap();
+        let static_identifier = TableIdent::from_strs(["static_ns", "static_table"]).unwrap();
+        let static_table =
+            StaticTable::from_metadata_file(&metadata_file_path, static_identifier, file_io)
+                .await
+                .unwrap();
+        static_table.into_table()
+    }
+
+    #[tokio::test]
+    async fn test_try_new_from_table() {
+        let table = get_test_table_from_metadata_file().await;
+        let table_provider = IcebergTableProvider::try_new_from_table(table.clone())
+            .await
+            .unwrap();
+        let ctx = SessionContext::new();
+        ctx.register_table("mytable", Arc::new(table_provider))
+            .unwrap();
+        let df = ctx.sql("SELECT * FROM mytable").await.unwrap();
+        let df_schema = df.schema();
+        let df_columns = df_schema.fields();
+        assert_eq!(df_columns.len(), 3);
+        let x_column = df_columns.first().unwrap();
+        let column_data = format!(
+            "{:?}:{:?}",
+            x_column.name(),
+            x_column.data_type().to_string()
+        );
+        assert_eq!(column_data, "\"x\":\"Int64\"");
+        let has_column = df_schema.has_column(&Column::from_name("z"));
+        assert!(has_column);
+    }
+}

crates/integrations/datafusion/tests/test_data/TableMetadataV2Valid.json

@@ -0,0 +1,122 @@
+{
+  "format-version": 2,
+  "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
+  "location": "s3://bucket/test/location",
+  "last-sequence-number": 34,
+  "last-updated-ms": 1602638573590,
+  "last-column-id": 3,
+  "current-schema-id": 1,
+  "schemas": [
+    {
+      "type": "struct",
+      "schema-id": 0,
+      "fields": [
+        {
+          "id": 1,
+          "name": "x",
+          "required": true,
+          "type": "long"
+        }
+      ]
+    },
+    {
+      "type": "struct",
+      "schema-id": 1,
+      "identifier-field-ids": [
+        1,
+        2
+      ],
+      "fields": [
+        {
+          "id": 1,
+          "name": "x",
+          "required": true,
+          "type": "long"
+        },
+        {
+          "id": 2,
+          "name": "y",
+          "required": true,
+          "type": "long",
+          "doc": "comment"
+        },
+        {
+          "id": 3,
+          "name": "z",
+          "required": true,
+          "type": "long"
+        }
+      ]
+    }
+  ],
+  "default-spec-id": 0,
+  "partition-specs": [
+    {
+      "spec-id": 0,
+      "fields": [
+        {
+          "name": "x",
+          "transform": "identity",
+          "source-id": 1,
+          "field-id": 1000
+        }
+      ]
+    }
+  ],
+  "last-partition-id": 1000,
+  "default-sort-order-id": 3,
+  "sort-orders": [
+    {
+      "order-id": 3,
+      "fields": [
+        {
+          "transform": "identity",
+          "source-id": 2,
+          "direction": "asc",
+          "null-order": "nulls-first"
+        },
+        {
+          "transform": "bucket[4]",
+          "source-id": 3,
+          "direction": "desc",
+          "null-order": "nulls-last"
+        }
+      ]
+    }
+  ],
+  "properties": {},
+  "current-snapshot-id": 3055729675574597004,
+  "snapshots": [
+    {
+      "snapshot-id": 3051729675574597004,
+      "timestamp-ms": 1515100955770,
+      "sequence-number": 0,
+      "summary": {
+        "operation": "append"
+      },
+      "manifest-list": "s3://a/b/1.avro"
+    },
+    {
+      "snapshot-id": 3055729675574597004,
+      "parent-snapshot-id": 3051729675574597004,
+      "timestamp-ms": 1555100955770,
+      "sequence-number": 1,
+      "summary": {
+        "operation": "append"
+      },
+      "manifest-list": "s3://a/b/2.avro",
+      "schema-id": 1
+    }
+  ],
+  "snapshot-log": [
+    {
+      "snapshot-id": 3051729675574597004,
+      "timestamp-ms": 1515100955770
+    },
+    {
+      "snapshot-id": 3055729675574597004,
+      "timestamp-ms": 1555100955770
+    }
+  ],
+  "metadata-log": []
+}