feat(FR-1436): limit deployment model folder selector to mountable hosts

[agatha197]

Resolves #4234 (FR-1436)

Problem

The model folder picker on the deployment "add revision" modal (DeploymentAddRevisionModal, both the preset and custom forms) listed every usage_mode == "model" vfolder, regardless of whether the folder's storage host is mountable by the user. Picking a non-mountable-host folder (e.g. a left-over model-store project folder) reproduces the customer report: the request fails.

In the deployment flow this is actually worse than the legacy model-service flow. The backend defers the storage-host mount-permission check (MOUNT_IN_SESSION) to session start / replica spawn, not deployment creation:

repositories/deployment/db_source/db_source.py — "Intentionally minimal: only the permission column is read, without RBAC / host-permission / cross-project checks — those apply at session creation (prepare_vfolder_mounts), not at revision write."

So a deployment built from a non-mountable-host model folder is accepted, looks created, and then its replicas silently fail to spawn with InsufficientStoragePermission (HTTP 400). Front-end filtering is the right place to prevent this up front.

Change

Filter both model-folder selectors to folders whose host the current user may actually mount:

• New hook useMountableVFolderHosts reads the myStorageHostPermissions GraphQL field (Strawberry V2) and returns the host names carrying MOUNT_IN_SESSION.
• The host names are composed into the existing GraphQL filter string as usage_mode == "model" & (host == "h1" | host == "h2" | …). host is server-side filterable on vfolder_nodes, so this keeps the selector's pagination/count intact. When the user has no mountable host, the filter matches nothing (rather than every folder).

Why myStorageHostPermissions (no waterfall)

The legacy client-side pattern (VFolderTable, useMergedAllowedStorageHostPermission) first resolves the keypair's resource-policy name, then issues a second query for domain/group/keypair allowed_vfolder_hosts, then merges three JSON blobs client-side — a request waterfall. myStorageHostPermissions returns the union of domain + the user's projects + keypair permissions in a single query, already intersected with the registered volumes, server-side. No keypair lookup, no client merge.

No @since gate is needed: this modal is already gated to managers ≥ 26.4.3, and myStorageHostPermissions was added in 26.4.2.

Scope notes

• Host filter only. Group/project (ownership_type == "group") folders are intentionally not excluded here. The backend explicitly accepts group-owned MODEL folders at deployment creation, so excluding them would contradict backend intent; the customer-reported folders are correctly handled by the host filter (their host is simply not mountable). (The original FR-1435 group-exclusion lives in the now-refactored ServiceLauncherPageContent; whether to reinstate it under the new modal is tracked separately.)
• Known nuance. myStorageHostPermissions is scoped to the user (the union across all of the user's projects), so it is a slight superset of the hosts mountable in one specific project. This is strictly better than today (no filter) and acceptable; strict per-project scoping is out of scope here.
• Follow-up (separate stack). Migrating the existing waterfall consumers (VFolderTable, useMergedAllowedStorageHostPermission + its file-browser / SFTP / folder-explorer consumers) onto myStorageHostPermissions is tracked as a separate Jira issue and will be stacked on top of this PR.

Verification

bash scripts/verify.sh → Relay / Lint / Format / TypeScript PASS.

Test plan

• As a user whose project has a model folder on a non-mountable host, open the deployment "add revision" modal → that folder is not offered in the model folder selector (preset and custom forms).
• A model folder on a mountable host is still offered and a deployment created from it spawns replicas successfully.
• A user with no mountable hosts sees an empty model folder selector (not the full list).

🤖 Generated with Claude Code

[agatha197]

• refactor(FR-3229): replace allowed_vfolder_hosts waterfall with myStorageHostPermissions #8086
• feat(FR-1436): limit deployment model folder selector to mountable hosts #8083 👈 (View in Graphite)
• main

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[github-actions]

Coverage Report for react-coverage (./react)

Status	Category	Percentage	Covered / Total
🔵	Lines	6.72%	1947 / 28945
🔵	Statements	5.49%	2194 / 39928
🔵	Functions	5.67%	322 / 5679
🔵	Branches	3.68%	1387 / 37649

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
react/src/components/DeploymentAddRevisionModal.tsx	0%	0%	0%	0%	169-233
react/src/hooks/useMountableVFolderHosts.ts	0%	0%	0%	0%	23-42

Generated in workflow #2407 for commit 31a8c97 by the Vitest Coverage Report Action

[Copilot]

Pull request overview

This PR prevents users from selecting model vfolders on storage hosts they cannot mount, avoiding deployments that are accepted at creation time but later fail during replica spawn due to missing MOUNT_IN_SESSION permission.

Changes:

• Added useMountableVFolderHosts hook that queries myStorageHostPermissions and derives the set of mountable storage hosts for the current user.
• Updated DeploymentAddRevisionModal’s model folder selectors (preset + custom forms) to apply a server-side filter combining usage_mode == "model" with an OR-list of mountable host == ... clauses.
• Added the Relay generated query artifact for the new hook.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
react/src/hooks/useMountableVFolderHosts.ts	New Relay-backed hook to fetch mountable storage hosts via myStorageHostPermissions.
react/src/components/DeploymentAddRevisionModal.tsx	Applies host-based filtering to both model folder pickers to exclude non-mountable hosts.
react/src/generated/useMountableVFolderHostsQuery.graphql.ts	Relay generated query/types for useMountableVFolderHosts.

Files not reviewed (1)

• react/src/generated/useMountableVFolderHostsQuery.graphql.ts: Generated file