s3tables: redesign Iceberg REST Catalog using iceberg-go and automate integration tests (#8197)

* full integration with iceberg-go

* Table Commit Operations (handleUpdateTable)

* s3tables: fix Iceberg v2 compliance and namespace properties

This commit ensures SeaweedFS Iceberg REST Catalog is compliant with
Iceberg Format Version 2 by:
- Using iceberg-go's table.NewMetadataWithUUID for strict v2 compliance.
- Explicitly initializing namespace properties to empty maps.
- Removing omitempty from required Iceberg response fields.
- Fixing CommitTableRequest unmarshaling using table.Requirements and table.Updates.

* s3tables: automate Iceberg integration tests

- Added Makefile for local test execution and cluster management.
- Added docker-compose for PyIceberg compatibility kit.
- Added Go integration test harness for PyIceberg.
- Updated GitHub CI to run Iceberg catalog tests automatically.

* s3tables: update PyIceberg test suite for compatibility

- Updated test_rest_catalog.py to use latest PyIceberg transaction APIs.
- Updated Dockerfile to include pyarrow and pandas dependencies.
- Improved namespace and table handling in integration tests.

* s3tables: address review feedback on Iceberg Catalog

- Implemented robust metadata version parsing and incrementing.
- Ensured table metadata changes are persisted during commit (handleUpdateTable).
- Standardized namespace property initialization for consistency.
- Fixed unused variable and incorrect struct field build errors.

* s3tables: finalize Iceberg REST Catalog and optimize tests

- Implemented robust metadata versioning and persistence.
- Standardized namespace property initialization.
- Optimized integration tests using pre-built Docker image.
- Added strict property persistence validation to test suite.
- Fixed build errors from previous partial updates.

* Address PR review: fix Table UUID stability, implement S3Tables UpdateTable, and support full metadata persistence individually

* fix: Iceberg catalog stable UUIDs, metadata persistence, and file writing

- Ensure table UUIDs are stable (do not regenerate on load).
- Persist full table metadata (Iceberg JSON) in s3tables extended attributes.
- Add `MetadataVersion` to explicitly track version numbers, replacing regex parsing.
- Implement `saveMetadataFile` to persist metadata JSON files to the Filer on commit.
- Update `CreateTable` and `UpdateTable` handlers to use the new logic.

* test: bind weed mini to 0.0.0.0 in integration tests to fix Docker connectivity

* Iceberg: fix metadata handling in REST catalog

- Add nil guard in createTable
- Fix updateTable to correctly load existing metadata from storage
- Ensure full metadata persistence on updates
- Populate loadTable result with parsed metadata

* S3Tables: add auth checks and fix response fields in UpdateTable

- Add CheckPermissionWithContext to UpdateTable handler
- Include TableARN and MetadataLocation in UpdateTable response
- Use ErrCodeConflict (409) for version token mismatches

* Tests: improve Iceberg catalog test infrastructure and cleanup

- Makefile: use PID file for precise process killing
- test_rest_catalog.py: remove unused variables and fix f-strings

* Iceberg: fix variable shadowing in UpdateTable

- Rename inner loop variable `req` to `requirement` to avoid shadowing outer request variable

* S3Tables: simplify MetadataVersion initialization

- Use `max(req.MetadataVersion, 1)` instead of anonymous function

* Tests: remove unicode characters from S3 tables integration test logs

- Remove unicode checkmarks from test output for cleaner logs

* Iceberg: improve metadata persistence robustness

- Fix MetadataLocation in LoadTableResult to fallback to generated location
- Improve saveMetadataFile to ensure directory hierarchy existence and robust error handling

weed/s3api/s3tables/utils.go

@@ -79,18 +79,18 @@ func parseTableFromARN(arn string) (bucketName, namespace, tableName string, err
 
 // Path helpers
 
-// getTableBucketPath returns the filer path for a table bucket
-func getTableBucketPath(bucketName string) string {
+// GetTableBucketPath returns the filer path for a table bucket
+func GetTableBucketPath(bucketName string) string {
 	return path.Join(TablesPath, bucketName)
 }
 
-// getNamespacePath returns the filer path for a namespace
-func getNamespacePath(bucketName, namespace string) string {
+// GetNamespacePath returns the filer path for a namespace
+func GetNamespacePath(bucketName, namespace string) string {
 	return path.Join(TablesPath, bucketName, namespace)
 }
 
-// getTablePath returns the filer path for a table
-func getTablePath(bucketName, namespace, tableName string) string {
+// GetTablePath returns the filer path for a table
+func GetTablePath(bucketName, namespace, tableName string) string {
 	return path.Join(TablesPath, bucketName, namespace, tableName)
 }
 
@@ -118,6 +118,7 @@ type tableMetadataInternal struct {
 	ModifiedAt       time.Time      `json:"modifiedAt"`
 	OwnerAccountID   string         `json:"ownerAccountId"`
 	VersionToken     string         `json:"versionToken"`
+	MetadataVersion  int            `json:"metadataVersion"`
 	MetadataLocation string         `json:"metadataLocation,omitempty"`
 	Metadata         *TableMetadata `json:"metadata,omitempty"`
 }