New Flink Relations view mode showing toplevel relations + their direct columns

[jlrobins]

Summary of Changes

• New system catalog query performing the UNION ALL between INFORMATION_SCHEMA.TABLES (sic) and ....COLUMNS to learn about all of the relations (Kafka-backed tables, views, system tables, external tables) in a Flink database, wrapped by new CCloudResourceLoader method getFlinkRelations().
• New models for Flink relations, columns, src/models/flinkRelation.ts.
• New view mode over Flink relations, now the default mode, showing relations + their direct columns.

Optional: Click-testing instructions

1. Log into CCloud.
2. Tell the Flink Database view to set itself to a Flinkable cluster like RealworldData.
3. Explore the tables and view, admire their columns + type definitions.

Optional: Any additional details or context that should be provided?

• Future work implements a recursive descent parser over the column and UDF type definition strings, then allowing better insight into composite column types, of which we have some good examples in RealworldData. That will then enable us to nest / expand these columns in the near future. Will aim for the parser + its new types to be an independent module so as could be reused for CCloudUI.
• Closes System catalog query + modeling for relation columns #2849
• Closes Make the new Flink Relations sub-mode of the existing Flink Database view #2841

Pull request checklist

Please check if your PR fulfills the following (if applicable):

Tests

• Added new
• Updated existing
• Deleted existing

Release notes

• Does anything in this PR need to be mentioned in the user-facing CHANGELOG?

[Copilot]

Pull Request Overview

This PR introduces a new Flink Relations view mode for browsing database tables, views, and their columns. The relations view becomes the new default mode, replacing UDFs as the initial view. The implementation includes new models for Flink relations and columns, a system catalog query that unions table and column metadata, and comprehensive test coverage.

Key changes:

• New default view mode showing Flink relations (tables/views) with their columns
• Consolidated system catalog models in flinkSystemCatalog.ts (moved from flinkUDF.ts)
• New system catalog query combining INFORMATION_SCHEMA.TABLES and COLUMNS data

Reviewed Changes

Copilot reviewed 28 out of 28 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tests/unit/testResources/makeRelationRow.ts	New test helper functions for creating mock relation and column data
tests/unit/testResources/flinkUDF.ts	Updated import path for consolidated system catalog models
tests/unit/testResources/flinkRelation.ts	New test fixtures for relations and columns
src/viewProviders/multiViewDelegates/flinkUDFsDelegate.ts	Updated imports for renamed model file
src/viewProviders/multiViewDelegates/flinkUDFsDelegate.test.ts	Added extension context setup and updated imports
src/viewProviders/multiViewDelegates/flinkRelationsDelegate.ts	New delegate implementing relations view logic
src/viewProviders/multiViewDelegates/flinkRelationsDelegate.test.ts	Comprehensive tests for relations delegate
src/viewProviders/multiViewDelegates/constants.ts	Added Relations view mode enum value
src/viewProviders/flinkDatabase.ts	Integrated relations delegate and set as default view
src/viewProviders/flinkDatabase.test.ts	Updated tests with async setup and UDFs mode initialization
src/viewProviders/baseModels/multiViewBase.ts	Enhanced getChildren signature to support parent elements
src/storage/resourceManager.ts	Updated import for consolidated models
src/storage/resourceManager.test.ts	Updated import for consolidated models
src/models/flinkUDF.ts	File deleted, moved to flinkSystemCatalog.ts
src/models/flinkUDF.test.ts	File deleted, tests moved to flinkSystemCatalog.test.ts
src/models/flinkSystemCatalog.ts	New consolidated file with UDF, relation, and column models
src/models/flinkSystemCatalog.test.ts	Comprehensive tests for all system catalog models
src/loaders/utils/udfSystemCatalogQuery.ts	Updated imports for consolidated models
src/loaders/utils/udfSystemCatalogQuery.test.ts	Added explicit type annotations for parameters
src/loaders/utils/relationsAndColumnsSystemCatalogQuery.ts	New query builder and parser for relations/columns data
src/loaders/utils/relationsAndColumnsSystemCatalogQuery.test.ts	Tests for query generation and response parsing
src/loaders/ccloudResourceLoader.ts	Added getFlinkRelations method
src/loaders/ccloudResourceLoader.test.ts	Tests for new getFlinkRelations method
src/extension.ts	Registered new view commands and updated default mode
src/commands/flinkUDFs.ts	Updated imports for consolidated models
src/commands/flinkDatabaseView.ts	New command for switching to relations view
src/commands/flinkDatabaseView.test.ts	Tests for relations view command
package.json	Added relations view mode command and menu entries

[jlrobins]

This module doing the system catalog query + parsing into model objs is 100% parallel to how we did it for UDFs + UDF parameters over in src/loaders/utils/udfSystemCatalogQuery.ts

See:

• https://docs.confluent.io/cloud/current/flink/reference/flink-sql-information-schema.html#flink-sql-information-schema-tables
• https://docs.confluent.io/cloud/current/flink/reference/flink-sql-information-schema.html#columns

[shouples]

Good stuff, works great! Minor test suggestion, and I think moving all of the UDF models into models/flinkSystemCatalog might cause a little dev friction but I get the reasoning

[jlrobins]

This external function / its test now moved over into src/utils/flinkTypes[.test].ts. The function is also used by src/models/flinkSystemCatalog.ts

[sonarqube-confluent]

Analysis Details

6 Issues

• 0 Bugs
• 0 Vulnerabilities
• 6 Code Smells

Coverage and Duplications

• 94.20% Coverage (73.80% Estimated after merge)
• No duplication information (0.50% Estimated after merge)

Project ID: vscode

View in SonarQube

[shouples]

One more follow-up item: #2937