OPC # 0006: OPC Git Trunk-Based management

Co-authored-by: Copilot <copilot@github.com>

ControlPlane.Api/Program.cs

@@ -166,6 +166,7 @@ await using (var cmd = ds.CreateCommand("""
 // Idempotent column additions for schema migrations
 await using (var migCmd = ds.CreateCommand("""
     ALTER TABLE release_record ADD COLUMN IF NOT EXISTS opc_numbers TEXT[] NOT NULL DEFAULT '{}';
+    ALTER TABLE release_record ADD COLUMN IF NOT EXISTS commit_sha  VARCHAR(40);
     """))
     await migCmd.ExecuteNonQueryAsync();
 

ControlPlane.Api/Services/PromotionService.cs

@@ -787,6 +787,64 @@ public class PromotionService(IConfiguration config, ILogger<PromotionService> l
             return [];
         }
     }
+
+    /// <summary>
+    /// Returns distinct, sorted OPC numbers for commits reachable from <paramref name="toSha"/>
+    /// that are NOT reachable from <paramref name="fromSha"/> — i.e. the exact delta for this release.
+    /// Falls back to <see cref="ExtractOpcNumbersAsync"/> (last 50 commits) when <paramref name="fromSha"/>
+    /// is null (first-ever release for this environment).
+    /// </summary>
+    public Task<List<string>> ExtractOpcNumbersDeltaAsync(
+        string  repoName,
+        string  toSha,
+        string? fromSha,
+        CancellationToken ct = default) =>
+        fromSha is null
+            ? ExtractOpcNumbersAsync(repoName, ct: ct)
+            : Task.Run(() => ExtractOpcNumbersDeltaCore(repoName, toSha, fromSha), ct);
+
+    private List<string> ExtractOpcNumbersDeltaCore(string repoName, string toSha, string fromSha)
+    {
+        var repoPath = GetRepoPath(repoName);
+        if (string.IsNullOrWhiteSpace(repoPath) || !Directory.Exists(repoPath))
+            return [];
+        try
+        {
+            using var repo = new Repository(repoPath);
+            var toCommit   = repo.Lookup<Commit>(toSha);
+            var fromCommit = repo.Lookup<Commit>(fromSha);
+            if (toCommit is null) return [];
+
+            var filter = fromCommit is null
+                ? new CommitFilter { IncludeReachableFrom = toCommit }
+                : new CommitFilter { IncludeReachableFrom = toCommit, ExcludeReachableFrom = fromCommit };
+
+            var set = new HashSet<string>(StringComparer.Ordinal);
+            foreach (var commit in repo.Commits.QueryBy(filter))
+                foreach (System.Text.RegularExpressions.Match m in OpcTagPattern.Matches(commit.Message))
+                    set.Add($"OPC # {m.Groups[1].Value.PadLeft(4, '0')}");
+
+            return [.. set.OrderBy(x => x)];
+        }
+        catch (Exception ex)
+        {
+            logger.LogWarning(ex, "ExtractOpcNumbersDelta failed for {Repo} {From}..{To}", repoName, fromSha[..7], toSha[..7]);
+            return [];
+        }
+    }
+
+    /// <summary>Returns the full HEAD SHA of <paramref name="branch"/> in <paramref name="repoName"/>, or null.</summary>
+    public string? GetBranchTipSha(string repoName, string branch)
+    {
+        var repoPath = GetRepoPath(repoName);
+        if (string.IsNullOrWhiteSpace(repoPath) || !Directory.Exists(repoPath)) return null;
+        try
+        {
+            using var repo = new Repository(repoPath);
+            return (repo.Branches[$"origin/{branch}"] ?? repo.Branches[branch])?.Tip?.Sha;
+        }
+        catch { return null; }
+    }
 }
 
 /// <summary>A single unreleased commit — carries full SHA for cherry-pick operations.</summary>

ControlPlane.Api/Services/ReleaseService.cs

@@ -51,7 +51,12 @@ public class ReleaseService(
             return blocked;
         }
 
-        var record = await history.CreateReleaseAsync(targetEnv, ImageName);
+        // Resolve the Clarity branch for this environment and stamp the HEAD SHA
+        // before creating the record so we capture "what was deployed" accurately.
+        var branch    = targetEnv switch { "fdev" => "develop", "staging" => "staging", "uat" => "uat", _ => "main" };
+        var currentSha = promotions.GetBranchTipSha("Clarity", branch);
+
+        var record = await history.CreateReleaseAsync(targetEnv, ImageName, currentSha);
 
         try
         {
@@ -183,9 +188,16 @@ public class ReleaseService(
         }
         finally
         {
-            // Stamp OPC ticket numbers from recent commits on the target branch.
-            var branch = targetEnv switch { "fdev" => "develop", "staging" => "staging", "uat" => "uat", _ => "main" };
-            try   { record.OpcNumbers = await promotions.ExtractOpcNumbersAsync("Clarity", branch, 50, ct); }
+            // Stamp the exact OPC ticket numbers introduced by this release:
+            // diff from previous release's SHA to this release's SHA on the Clarity branch.
+            try
+            {
+                var prev = await history.GetLastSuccessfulReleaseForEnvAsync(targetEnv);
+                // Exclude the current (in-flight) record — it's not succeeded yet
+                var prevSha = prev?.Id == record.Id ? null : prev?.CommitSha;
+                if (currentSha is not null)
+                    record.OpcNumbers = await promotions.ExtractOpcNumbersDeltaAsync("Clarity", currentSha, prevSha, ct);
+            }
             catch { /* git not configured — continue without OPC stamp */ }
 
             await history.UpdateReleaseAsync(record);