Method view_manifest

atomic-repository/src/repository/views.rs:633–682

Export a view's complete identity as a [`ViewManifest`]. The manifest carries the view's change log **exactly as stored** in `VIEW_CHANGES` (for a draft this includes the inherited prefix copied at fork time), plus scope, parent name, and the view's merkle state. The exported manifest is verified before it is returned, so a corrupted log surfaces here rather than on the receiving end.

(&self, name: &str)

    /// The exported manifest is verified before it is returned, so a
    /// corrupted log surfaces here rather than on the receiving end.
    pub fn view_manifest(&self, name: &str) -> Result<ViewManifest, RepositoryError> {
        let txn = self
            .pristine
            .read_txn()
            .map_err(|e| RepositoryError::Database(e.to_string()))?;

        let view = txn
            .get_view(name)
            .map_err(|e| RepositoryError::Database(e.to_string()))?
            .ok_or_else(|| RepositoryError::ViewNotFound {
                name: name.to_string(),
            })?;

        let parent = match view.parent {
            Some(parent_id) => txn
                .get_view_by_id(parent_id)
                .map_err(|e| RepositoryError::Database(e.to_string()))?
                .map(|p| p.name),
            None => None,
        };

        let mut changes = Vec::with_capacity(view.change_count as usize);
        for item in txn
            .iter_changes(&view, 0)
            .map_err(|e| RepositoryError::Database(e.to_string()))?
        {
            let (_seq, node_id, _merkle) =
                item.map_err(|e| RepositoryError::Database(e.to_string()))?;
            let hash = txn
                .get_external(node_id)
                .map_err(|e| RepositoryError::Database(e.to_string()))?
                .ok_or_else(|| {
                    RepositoryError::Database(format!(
                        "change {} in view '{}' has no external hash",
                        node_id.0, name
                    ))
                })?;
            changes.push(hash);
        }

        let manifest = ViewManifest {
            name: view.name.clone(),
            scope: view.kind,
            parent,
            changes,
            state: view.state,
        };
        manifest.verify()?;
        Ok(manifest)
    }

    /// Declaratively apply a [`ViewManifest`]: create the view with its
    /// declared identity if absent, then fast-forward its change log to