WIP: move changes hash contents into approval

Signed-off-by: Nick Gerace <nick@systeminit.com>

lib/dal/src/change_set/approval.rs

@@ -1,6 +1,34 @@
+//! Provides the ability to approve change sets and calculate their approval status.
+
+#![warn(
+    bad_style,
+    clippy::missing_panics_doc,
+    clippy::panic,
+    clippy::panic_in_result_fn,
+    clippy::unwrap_in_result,
+    clippy::unwrap_used,
+    dead_code,
+    improper_ctypes,
+    missing_debug_implementations,
+    missing_docs,
+    no_mangle_generic_items,
+    non_shorthand_field_patterns,
+    overflowing_literals,
+    path_statements,
+    patterns_in_fns_without_body,
+    unconditional_recursion,
+    unreachable_pub,
+    unused,
+    unused_allocation,
+    unused_comparisons,
+    unused_parens,
+    while_true
+)]
+
 use chrono::{DateTime, Utc};
 use serde::{Deserialize, Serialize};
 use si_data_pg::{PgError, PgRow};
+use si_events::ChangesHash;
 use si_id::{ChangeSetApprovalId, ChangeSetId, UserPk};
 use telemetry::prelude::*;
 use thiserror::Error;
@@ -9,8 +37,7 @@ pub use si_events::ChangeSetApprovalStatus;
 
 use crate::{DalContext, HistoryActor, TransactionsError, WorkspaceSnapshotError};
 
-pub mod changes_hash;
-
+#[allow(missing_docs)]
 #[derive(Debug, Error)]
 pub enum ChangeSetApprovalError {
     #[error("invalid user for creating a change set approval")]
@@ -27,6 +54,7 @@ pub enum ChangeSetApprovalError {
 
 type Result<T> = std::result::Result<T, ChangeSetApprovalError>;
 
+/// An individual approval for applying a [`ChangeSet`](crate::ChangeSet).
 #[derive(Debug, Serialize, Deserialize)]
 pub struct ChangeSetApproval {
     id: ChangeSetApprovalId,
@@ -57,6 +85,7 @@ impl TryFrom<PgRow> for ChangeSetApproval {
 }
 
 impl ChangeSetApproval {
+    /// Creates a new approval.
     #[instrument(name = "change_set.approval.new", level = "info", skip_all)]
     pub async fn new(
         ctx: &DalContext,
@@ -80,22 +109,27 @@ impl ChangeSetApproval {
         Self::try_from(row)
     }
 
+    /// Returns the ID of the approval.
     pub fn id(&self) -> ChangeSetApprovalId {
         self.id
     }
 
+    /// Returns the status of the approval.
     pub fn status(&self) -> ChangeSetApprovalStatus {
         self.status
     }
 
+    /// Returns the ID of the approver.
     pub fn user_id(&self) -> UserPk {
         self.user_id
     }
 
+    /// Returns the checksum based on the changes compared to HEAD when the approval was performed.
     pub fn checksum(&self) -> &str {
         self.checksum.as_str()
     }
 
+    /// Lists all approvals in the [`ChangeSet`](crate::ChangeSet).
     #[instrument(name = "change_set.approval.list", level = "info", skip_all)]
     pub async fn list(ctx: &DalContext) -> Result<Vec<Self>> {
         let change_set_id = ctx.change_set_id();
@@ -114,4 +148,18 @@ impl ChangeSetApproval {
         }
         Ok(approvals)
     }
+
+    /// Generates a checksum for changes in the current [`ChangeSet`](crate::ChangeSet).
+    pub async fn generate_checksum(ctx: &DalContext) -> Result<ChangesHash> {
+        let mut changes = ctx
+            .workspace_snapshot()?
+            .detect_changes_from_head(ctx)
+            .await?;
+        changes.sort_by_key(|c| c.id);
+        let mut hasher = ChangesHash::hasher();
+        for change in changes {
+            hasher.update(change.merkle_tree_hash.as_bytes());
+        }
+        Ok(hasher.finalize())
+    }
 }

lib/dal/src/workspace_snapshot.rs

@@ -747,6 +747,24 @@ impl WorkspaceSnapshot {
         .await?)
     }
 
+    /// A wrapper around [`Self::detect_changes`](Self::detect_changes) where the "onto" snapshot is derived from the
+    /// workspace's default [`ChangeSet`](crate::ChangeSet).
+    #[instrument(
+        name = "workspace_snapshot.detect_changes_from_head",
+        level = "debug",
+        skip_all
+    )]
+    pub async fn detect_changes_from_head(
+        &self,
+        ctx: &DalContext,
+    ) -> WorkspaceSnapshotResult<Vec<Change>> {
+        let head_change_set_id = ctx.get_workspace_default_change_set_id().await?;
+        let head_snapshot = Self::find_for_change_set(&ctx, head_change_set_id).await?;
+        Ok(head_snapshot
+            .detect_changes(&ctx.workspace_snapshot()?.clone())
+            .await?)
+    }
+
     /// Gives the exact node index endpoints of an edge.
     pub async fn edge_endpoints(
         &self,

lib/dal/tests/integration_test/change_set/approval.rs

@@ -1,6 +1,6 @@
 use std::collections::HashSet;
 
-use dal::change_set::approval::{self, ChangeSetApproval, ChangeSetApprovalStatus};
+use dal::change_set::approval::{ChangeSetApproval, ChangeSetApprovalStatus};
 use dal::{DalContext, Ulid};
 use dal_test::color_eyre::eyre::OptionExt;
 use dal_test::helpers::{
@@ -15,8 +15,7 @@ async fn new(ctx: &mut DalContext) -> Result<()> {
     ChangeSetTestHelpers::commit_and_update_snapshot_to_visibility(ctx).await?;
 
     let status = ChangeSetApprovalStatus::Approved;
-    let hash = approval::changes_hash::changes_hash(ctx).await?;
-    let checksum = hash.to_string();
+    let checksum = ChangeSetApproval::generate_checksum(ctx).await?.to_string();
 
     let new_approval = ChangeSetApproval::new(ctx, status, checksum).await?;
     assert_eq!(
@@ -45,7 +44,10 @@ async fn status(ctx: &mut DalContext) -> Result<()> {
         .await?;
     ChangeSetTestHelpers::commit_and_update_snapshot_to_visibility(ctx).await?;
 
-    let changes = approval::changes_hash::detect_changes_from_head(ctx).await?;
+    let changes = ctx
+        .workspace_snapshot()?
+        .detect_changes_from_head(ctx)
+        .await?;
     let seen: HashSet<Ulid> = HashSet::from_iter(changes.iter().map(|c| c.id));
     assert_eq!(
         changes.len(), // expected