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Operations history

What is a document model?​

A document model in Powerhouse is the core unit for managing business data. Each document (such as an invoice, contributor agreement, or scope of work) is created from a specific document model, which defines:

  • State schema: What data the document contains
  • Operations: What actions can modify that document

What is an operations history?​

Every time a user edits a document, they do so by submitting a document operation or a 'command' in CQRS (e.g., ADD_LINE_ITEM, UPDATE_RECIPIENT). These operations are:

  • Appended to the document's history
  • Immutable (you never overwrite; you always append)
  • Replayable — the current document state is the result of applying all past operations in sequence

This design is based on event sourcing principles.

Why use an operations history?​

  • Auditability: Inspect every change ever made to a document.
  • Transparency: Contributors see what others have done.
  • Versioning: Revert to any prior state or resolve conflicts using branching and merging.
  • Interoperability: Operations are just data—they can be signed, stored on-chain, or synchronized across systems.

Example: Invoice document​

Suppose you're editing a powerhouse/invoice document. Its operations history might look like this:

SET_RECIPIENT(name: "Acme Corp")
ADD_LINE_ITEM(description: "Design Work", unitCost: $500)
UPDATE_DUE_DATE(date: "2025-06-01")

The document's state at any time is the result of running those operations in order.

Visualizing the operations history​

Revision list and details​

In Connect the Powerhouse UI displays a chronologic list of all applied modifications to the document, each with a unique event ID, state hash, and commit message. You can inspect each revision for signatures and errors.

Revision History List

Viewing revision hashes and event IDs​

Hovering over a revision reveals its event ID and state hash, providing traceability for every change.

Revision Hash Popup

Signature verification​

Clicking the signature badge shows signature details, including signer address, hash, and verification status. This ensures every operation is cryptographically auditable. Read more about how we are using Renown for authentication & verification of signer data.

Signature Details Popup

Viewing committer addresses​

You can also view the committer's address for each revision, supporting full transparency and accountability.

Committer Address Popup

Replay, branch, and merge (under development)​

  • Replay: When you load a document, the system replays all operations to build its state.
  • Branch: Create a parallel version of the document to test changes or handle conflicts.
  • Merge: Combine branches intelligently based on operations, not just raw field values.