TIA Portal Multiuser Engineering

Scope

Multiuser Engineering workflows using the TIA Portal Openness API. Covers Local Sessions, Server Projects, and Multiuser Commissioning.

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Reference files

Load ONLY the reference file(s) relevant to the task.

Reference file	Load when the task involves
references/v21-api-surface.md	Comprehensive installed surface for Siemens.Engineering.Multiuser types.
references/workflows-and-safety.md	Exact V21 roots, project-server/session workflows, marking, locking, save/close/commit semantics, and remote-write gates.

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Key Workflows

Managing Local Sessions

1. Resolve a project-server connection from tiaPortal.ProjectServers by exact alias.
2. Resolve the exact ServerProjectInfo returned by ProjectServer.GetServerProjects().
3. Create a LocalSessionInfo, then open it through tiaPortal.LocalSessions.
4. Use LocalSession.Save(), Close(), IsUptoDate(), MarkingService, and—only for a supported server/exclusive session—CloseAndCommit(comment).

Use only the direct compositions and the session methods listed here. Do not translate UI terms into an intermediate service, conflict-options object, or parameterless check-in/update calls.

Project-server root

ProjectServerComposition servers = tiaPortal.ProjectServers;
LocalSessionComposition sessions = tiaPortal.LocalSessions;

Enforcement

1. Require explicit remote-write authorization before creating/deleting a connection or session, adding a project, changing host/protocol/port, saving, closing with discard, or committing a server revision.
2. Resolve server alias, project, group, session ID/path, and intended mode exactly; never select .First() or [0].
3. Check server lock state, session freshness, markings/conflicts, active users, and path/version prerequisites before mutation.
4. Active monitoring or forcing jobs must be stopped before check-in/update workflows; non-markable edits can be lost in commissioning workflows.
5. Close() discards pending changes. CloseAndCommit() performs a remote commit and returns the created revision; neither is cleanup to call unconditionally.
6. Do not save or commit unless explicitly requested. Do not claim remote success without reading the returned revision/current server state.