libstore: asyncify Store::getBuildDerivationPath

Change-Id: Ie9c41eab4bfa548aa19f6587d60d9c0250ef2f54

lix/libstore/log-store.cc

@@ -4,7 +4,7 @@ namespace nix {
 
 kj::Promise<Result<std::optional<std::string>>> LogStore::getBuildLog(const StorePath & path)
 try {
-    auto maybePath = getBuildDerivationPath(path);
+    auto maybePath = TRY_AWAIT(getBuildDerivationPath(path));
     if (!maybePath)
         co_return std::nullopt;
     co_return getBuildLogExact(maybePath.value());

lix/libstore/store-api.cc

@@ -1412,20 +1412,20 @@ Derivation readDerivationCommon(Store& store, const StorePath& drvPath, bool req
     }
 }
 
-std::optional<StorePath> Store::getBuildDerivationPath(const StorePath & path)
-{
+kj::Promise<Result<std::optional<StorePath>>> Store::getBuildDerivationPath(const StorePath & path)
+try {
 
     if (!path.isDerivation()) {
         try {
             auto info = queryPathInfo(path);
-            return info->deriver;
+            co_return info->deriver;
         } catch (InvalidPath &) {
-            return std::nullopt;
+            co_return std::nullopt;
         }
     }
 
     if (!experimentalFeatureSettings.isEnabled(Xp::CaDerivations) || !isValidPath(path))
-        return path;
+        co_return path;
 
     auto drv = readDerivation(path);
     if (!drv.type().hasKnownOutputPaths()) {
@@ -1433,10 +1433,12 @@ std::optional<StorePath> Store::getBuildDerivationPath(const StorePath & path)
         // resolved derivation, so we need to get it first
         auto resolvedDrv = drv.tryResolve(*this);
         if (resolvedDrv)
-            return writeDerivation(*this, *resolvedDrv, NoRepair, true);
+            co_return writeDerivation(*this, *resolvedDrv, NoRepair, true);
     }
 
-    return path;
+    co_return path;
+} catch (...) {
+    co_return result::current_exception();
 }
 
 Derivation Store::readDerivation(const StorePath & drvPath)

lix/libstore/store-api.hh

@@ -831,7 +831,7 @@ public:
      * - If the path is a content-addressed derivation, try to resolve it
      * - Otherwise, find one of its derivers
      */
-    std::optional<StorePath> getBuildDerivationPath(const StorePath &);
+    kj::Promise<Result<std::optional<StorePath>>> getBuildDerivationPath(const StorePath &);
 
     /**
      * Hack to allow long-running processes like hydra-queue-runner to