fix(hubble): fix loadfile limit

[lokidundun]

Purpose of the PR

• close [Bug] can't load files when > 10GB in hubble #496

Main Changes

Verifying these changes

• Trivial rework / code cleanup without any test coverage. (No Need)
• Already covered by existing tests, such as (please modify tests here).
• Need tests and can be verified as follows:
  • xxx

Does this PR potentially affect the following parts?

• Nope
• Dependencies (add/update license info)
• Modify configurations
• The public API
• Other affects (typed here)

Documentation Status

• Doc - TODO
• Doc - Done
• Doc - No Need

[Copilot]

Pull request overview

This PR addresses the upload “total file size limit” logic in Hubble’s backend, aiming to avoid incorrectly enforcing the limit across unrelated uploads (issue #496).

Changes:

• Add FileMappingService.listByConnId(connId) to fetch file mappings scoped to a graph connection.
• Update upload validation to sum sizes using listByConnId(connId) instead of listAll().
• Fix the i18n error key used when exceeding the total size limit (exceed-total-size).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
hugegraph-hubble/hubble-be/src/main/java/org/apache/hugegraph/service/load/FileMappingService.java	Adds a new query helper to list file mappings by conn_id.
hugegraph-hubble/hubble-be/src/main/java/org/apache/hugegraph/controller/load/FileUploadController.java	Updates total-size validation to be connection-scoped and uses the correct error key for total-limit violations.

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[Copilot]

The total upload limit is now computed by summing total_size across all FileMapping records for the connection. Since completed mappings are persisted (and totalSize is set on completion), this quota becomes cumulative across jobs and won’t “reset” when a new job is created, which seems to be the core problem described in #496. Consider scoping the sum to the current job (conn_id + job_id), or using jobEntity.getJobSize() (which is already maintained on upload/delete) so the limit is enforced per job and naturally resets between jobs.

[Copilot]

currentTotalSize is calculated by loading every FileMapping for the connection into memory and then reducing with boxed Longs. For large numbers of mappings this is unnecessarily expensive on every upload request. Consider using a DB-side SUM(total_size) aggregate (or at least mapToLong(...).sum()) to avoid allocating and iterating over full entities.

Suggested change

	.map(FileMapping::getTotalSize)
	.reduce(0L, (Long::sum));
	.mapToLong(FileMapping::getTotalSize)
	.sum();