libcmd: add new StoreConfigCommand class

src/libcmd/command.cc

@@ -4,6 +4,7 @@
 #include "nix/cmd/command.hh"
 #include "nix/cmd/legacy.hh"
 #include "nix/cmd/markdown.hh"
+#include "nix/store/globals.hh"
 #include "nix/store/store-open.hh"
 #include "nix/store/local-fs-store.hh"
 #include "nix/store/derivations.hh"
@@ -63,6 +64,25 @@ void NixMultiCommand::run()
     command->second->run();
 }
 
+StoreConfigCommand::StoreConfigCommand() {}
+
+ref<StoreConfig> StoreConfigCommand::getStoreConfig()
+{
+    if (!_storeConfig)
+        _storeConfig = createStoreConfig();
+    return ref<StoreConfig>(_storeConfig);
+}
+
+ref<StoreConfig> StoreConfigCommand::createStoreConfig()
+{
+    return resolveStoreConfig(StoreReference::parse(settings.storeUri.get()));
+}
+
+void StoreConfigCommand::run()
+{
+    run(getStoreConfig());
+}
+
 StoreCommand::StoreCommand() {}
 
 ref<Store> StoreCommand::getStore()
@@ -74,12 +94,20 @@ ref<Store> StoreCommand::getStore()
 
 ref<Store> StoreCommand::createStore()
 {
-    return openStore();
+    auto store = getStoreConfig()->openStore();
+    store->init();
+    return store;
 }
 
-void StoreCommand::run()
+void StoreCommand::run(ref<StoreConfig> storeConfig)
 {
-    run(getStore());
+    // We can either efficiently implement getStore/createStore with memoization,
+    // or use the StoreConfig passed in run.
+    // It's more efficient to memoize, especially since there are some direct users
+    // of getStore. The StoreConfig in both cases should be the same, though.
+    auto store = getStore();
+    assert(&*storeConfig == &store->config);
+    run(std::move(store));
 }
 
 CopyCommand::CopyCommand()
@@ -99,9 +127,9 @@ CopyCommand::CopyCommand()
     });
 }
 
-ref<Store> CopyCommand::createStore()
+ref<StoreConfig> CopyCommand::createStoreConfig()
 {
-    return srcUri.empty() ? StoreCommand::createStore() : openStore(srcUri);
+    return srcUri.empty() ? StoreCommand::createStoreConfig() : resolveStoreConfig(StoreReference::parse(srcUri));
 }
 
 ref<Store> CopyCommand::getDstStore()
@@ -257,18 +285,18 @@ MixProfile::MixProfile()
     });
 }
 
-void MixProfile::updateProfile(const StorePath & storePath)
+void MixProfile::updateProfile(Store & store_, const StorePath & storePath)
 {
     if (!profile)
         return;
-    auto store = getDstStore().dynamic_pointer_cast<LocalFSStore>();
+    auto * store = dynamic_cast<LocalFSStore *>(&store_);
     if (!store)
         throw Error("'--profile' is not supported for this Nix store");
     auto profile2 = absPath(*profile);
     switchLink(profile2, createGeneration(*store, profile2, storePath));
 }
 
-void MixProfile::updateProfile(const BuiltPaths & buildables)
+void MixProfile::updateProfile(Store & store, const BuiltPaths & buildables)
 {
     if (!profile)
         return;
@@ -292,7 +320,7 @@ void MixProfile::updateProfile(const BuiltPaths & buildables)
         throw UsageError(
             "'--profile' requires that the arguments produce a single store path, but there are %d", result.size());
 
-    updateProfile(result[0]);
+    updateProfile(store, result[0]);
 }
 
 MixDefaultProfile::MixDefaultProfile()

src/libcmd/include/nix/cmd/command.hh

@@ -41,27 +41,42 @@ struct NixMultiCommand : MultiCommand, virtual Command
 #pragma GCC diagnostic ignored "-Woverloaded-virtual"
 
 /**
- * A command that requires a \ref Store "Nix store".
+ * A command that requires a \ref StoreConfig store configuration.
  */
-struct StoreCommand : virtual Command
+struct StoreConfigCommand : virtual Command
 {
-    StoreCommand();
+    StoreConfigCommand();
     void run() override;
 
     /**
-     * Return the default Nix store.
+     * Return the default Nix store configuration.
      */
-    ref<Store> getStore();
+    ref<StoreConfig> getStoreConfig();
 
+    virtual ref<StoreConfig> createStoreConfig();
     /**
-     * Return the destination Nix store.
+     * Main entry point, with a `StoreConfig` provided
      */
-    virtual ref<Store> getDstStore()
-    {
-        return getStore();
-    }
+    virtual void run(ref<StoreConfig>) = 0;
+
+private:
+    std::shared_ptr<StoreConfig> _storeConfig;
+};
+
+/**
+ * A command that requires a \ref Store "Nix store".
+ */
+struct StoreCommand : virtual StoreConfigCommand
+{
+    StoreCommand();
+    void run(ref<StoreConfig>) override;
+
+    /**
+     * Return the default Nix store.
+     */
+    ref<Store> getStore();
 
-    virtual ref<Store> createStore();
+    ref<Store> createStore();
     /**
      * Main entry point, with a `Store` provided
      */
@@ -81,9 +96,9 @@ struct CopyCommand : virtual StoreCommand
 
     CopyCommand();
 
-    ref<Store> createStore() override;
+    ref<StoreConfig> createStoreConfig() override;
 
-    ref<Store> getDstStore() override;
+    ref<Store> getDstStore();
 };
 
 /**
@@ -315,11 +330,11 @@ struct MixProfile : virtual StoreCommand
     MixProfile();
 
     /* If 'profile' is set, make it point at 'storePath'. */
-    void updateProfile(const StorePath & storePath);
+    void updateProfile(Store & store, const StorePath & storePath);
 
     /* If 'profile' is set, make it point at the store path produced
        by 'buildables'. */
-    void updateProfile(const BuiltPaths & buildables);
+    void updateProfile(Store & store, const BuiltPaths & buildables);
 };
 
 struct MixDefaultProfile : MixProfile

src/nix/build.cc

@@ -182,7 +182,7 @@ struct CmdBuild : InstallablesCommand, MixOutLinkByDefault, MixDryRun, MixJSON,
         BuiltPaths buildables2;
         for (auto & b : buildables)
             buildables2.push_back(b.path);
-        updateProfile(buildables2);
+        updateProfile(*store, buildables2);
     }
 };
 

src/nix/copy.cc

@@ -63,7 +63,7 @@ struct CmdCopy : virtual CopyCommand, virtual BuiltPathsCommand, MixProfile, Mix
 
         copyPaths(*srcStore, *dstStore, stuffToCopy, NoRepair, checkSigs, substitute);
 
-        updateProfile(rootPaths);
+        updateProfile(*dstStore, rootPaths);
 
         if (outLink) {
             if (auto store2 = dstStore.dynamic_pointer_cast<LocalFSStore>())

src/nix/develop.cc

@@ -501,7 +501,7 @@ struct Common : InstallableCommand, MixProfile
     {
         auto shellOutPath = getShellOutPath(store, installable);
 
-        updateProfile(shellOutPath);
+        updateProfile(*store, shellOutPath);
 
         debug("reading environment file '%s'", store->printStorePath(shellOutPath));
 

src/nix/profile.cc

@@ -412,7 +412,7 @@ struct CmdProfileAdd : InstallablesCommand, MixDefaultProfile
         }
 
         try {
-            updateProfile(manifest.build(store));
+            updateProfile(*store, manifest.build(store));
         } catch (BuildEnvFileConflictError & conflictError) {
             // FIXME use C++20 std::ranges once macOS has it
             //       See
@@ -668,7 +668,7 @@ struct CmdProfileRemove : virtual EvalCommand, MixDefaultProfile, MixProfileElem
         auto removedCount = oldManifest.elements.size() - newManifest.elements.size();
         printInfo("removed %d packages, kept %d packages", removedCount, newManifest.elements.size());
 
-        updateProfile(newManifest.build(store));
+        updateProfile(*store, newManifest.build(store));
     }
 };
 
@@ -775,7 +775,7 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
             element.updateStorePaths(getEvalStore(), store, builtPaths.find(&*installable)->second.first);
         }
 
-        updateProfile(manifest.build(store));
+        updateProfile(*store, manifest.build(store));
     }
 };