Drafts, Versions and Real-Time Editing

A designed report has a published version, which is what people run, and a draft, which the builder saves into a moment after each change. Nobody sees the draft until someone publishes it. How people use drafts and versions is described in the User Manual: Publish and versions.

Drafts and revisions

• Autosave. Each change is sent to POST /Admin/reports/builder/{id}/draft with the revision the page has, a moment after it is made. The first change to a new report creates its draft (POST /Admin/reports/builder/drafts), which gets the report's identifier at once and keeps it when first published; until then the report exists only as that draft, is listed with a Not published badge for its owner and for people who manage every report, and can be continued or deleted (POST /Admin/reports/designs/drafts/{id}/delete). Saves are sent with keepalive, so a change made right before the page is closed or refreshed is still saved, and the page does not ask before leaving.
• Revisions. Every draft save, publish, discard and restore increases the report's revision, kept in its ReportDesignDraft document. A change based on an older revision is refused with 409 Conflict and the name of the person who changed it last; the page offers to reload their changes or to keep its own (which sends the change again with force). Changes to one report are serialized with Orchard Core's IDistributedLock, so the check holds on several nodes; a change that cannot take the lock in time is refused and the page asks to try again.
• Discarding (POST /Admin/reports/builder/{id}/draft/discard) drops the draft and returns to the published version.

Publishing and versions

• Publishing (POST /Admin/reports/builder/save) saves the report as before (title, sharing and data rules are checked), adds an immutable ReportDesignVersion only when the report's content differs from the latest version, and clears the draft. A report published before versions existed first gets its earlier state as version 1.
• Versions can be listed (GET /Admin/reports/builder/{id}/versions), previewed (GET /Admin/reports/builder/{id}/versions/{number}) and restored (POST /Admin/reports/builder/{id}/versions/{number}/restore): restoring copies a version into the draft, to be checked and published; the new version records which version it was restored from.
• Drafts and versions are separate YesSql documents with their own index tables (ReportDesignDraftIndex, ReportDesignVersionIndex), so autosaving one report never rewrites another. Deleting a report deletes its draft, its versions and its share links.
• Retention. At most MaxVersions versions are kept per report; the oldest are deleted when a report is published, and 0 keeps them all (see Configuration).

Every one of these endpoints checks ManageAllReportDesigns with the report as the resource (see Permissions). Reusable views have no drafts or versions: they are saved directly with POST /Admin/reports/views/save.

Real time

When OrchardCore.SignalR is enabled, the builder connects to ReportsHub (at /Communication/Hub/ReportsHub under the tenant's path). No separate feature is needed: the hub is registered by a startup class marked with [RequireFeatures("OrchardCore.SignalR")].

• Presence. A page subscribes to the report it edits; the hub checks that the user may edit it. Pages tell each other who arrived and left, and the builder shows the others' initials and a notice that changes can conflict. The server only relays these messages and keeps no list, so it works behind the Redis or Azure SignalR backplane.
• Changes. After a draft save, publish, discard, restore or delete is committed, SignalRReportDesignNotifier sends ReportDesignChanged (kind, designId, revision, versionNumber, userName) to the report's group. A page that is behind offers to reload. Group names are qualified by tenant with TenantSignalRGroupName.
• Without SignalR, the revision check still prevents silent overwrites; people find out when their next save is refused.

Other modules can react to report changes by replacing IReportDesignNotifier.