Struct MigrationReport 

#[non_exhaustive]
pub struct MigrationReport {
    pub rows_rewritten: u64,
    pub dry_run: bool,
    pub first_row_v1_chain_hash: String,
    pub first_row_v2_chain_hash: String,
}

Summary of a migrate_v1_to_v2 run.

Marked #[non_exhaustive] so future fields (e.g. a per-row error list, an aborted-row count) can be added without breaking callers that pattern-match.

Serialize enables provenance migrate --mode json (#204) — the wire form is {"rows_rewritten": N, "dry_run": bool, "first_row_v1_chain_hash": "...", "first_row_v2_chain_hash": "..."}.

Wire-format stability (post-#208 self-review §1)

Once a release ships with the Serialize derive, the field names below become part of the public API. Renaming a field is then a semver minor bump and warrants a CHANGELOG [BREAKING] note; new fields are still safe (per #[non_exhaustive]).

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

rows_rewritten: u64

Number of rows rewritten (or that WOULD be rewritten under dry_run).

dry_run: bool

Whether this was a dry-run preview (true) or a live rewrite (false).

first_row_v1_chain_hash: String

Stored this_hash of the first input row (the v1 chain anchor). "GENESIS" is reported as the literal "GENESIS" when the log was empty.

first_row_v2_chain_hash: String

Recomputed this_hash of the first migrated row under the v2 canonicalization. Equal to Self::first_row_v1_chain_hash only if the input was already v2 (idempotent case).

Trait Implementations

impl Clone for MigrationReport

fn clone(&self) -> MigrationReport

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MigrationReport

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Serialize for MigrationReport

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.