Dummy store compiles

obsidiansystems · Jul 17, 2024 · 596a682 · 596a682
1 parent 121e607
commit 596a682
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Showing 4 changed files with 62 additions and 28 deletions.
diff --git a/src/libstore/dummy-store.cc b/src/libstore/dummy-store.cc
@@ -1,12 +1,22 @@
 #include "store-api.hh"
+#include "store-registration.hh"
 #include "callback.hh"
 
 namespace nix {
 
+struct DummyStoreConfigDescription : virtual Store::Config::Description
+{
+    DummyStoreConfigDescription() : StoreConfigDescription{Store::Config::schema} {}
+};
+
 struct DummyStoreConfig : virtual StoreConfig {
     using StoreConfig::StoreConfig;
 
-    DummyStoreConfig(std::string_view scheme, std::string_view authority, const Params & params)
+    using Description = DummyStoreConfigDescription;
+
+    static const Description schema;
+
+    DummyStoreConfig(std::string_view scheme, std::string_view authority, const StoreReference::Params & params)
         : StoreConfig(params)
     {
         if (!authority.empty())
@@ -25,18 +35,20 @@ struct DummyStoreConfig : virtual StoreConfig {
     static std::set<std::string> uriSchemes() {
         return {"dummy"};
     }
+
+    std::shared_ptr<Store> open() override;
 };
 
+decltype(DummyStoreConfig::schema) DummyStoreConfig::schema{};
+
 struct DummyStore : public virtual DummyStoreConfig, public virtual Store
 {
-    DummyStore(std::string_view scheme, std::string_view authority, const Params & params)
-        : StoreConfig(params)
-        , DummyStoreConfig(scheme, authority, params)
-        , Store(params)
-    { }
+    using Config = DummyStoreConfig;
 
-    DummyStore(const Params & params)
-        : DummyStore("dummy", "", params)
+    DummyStore(const DummyStoreConfig & config)
+        : StoreConfig(config)
+        , DummyStoreConfig(config)
+        , Store(config)
     { }
 
     std::string getUri() override
@@ -86,6 +98,11 @@ struct DummyStore : public virtual DummyStoreConfig, public virtual Store
     { unsupported("getFSAccessor"); }
 };
 
-static RegisterStoreImplementation<DummyStore, DummyStoreConfig> regDummyStore;
+std::shared_ptr<Store> DummyStoreConfig::open()
+{
+    return std::make_shared<DummyStore>(*this);
+}
+
+static RegisterStoreImplementation<DummyStore> regDummyStore;
 
 }
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
@@ -197,7 +197,7 @@ const StoreConfigT<config::JustValue> storeConfigDefaults = {
     .systemFeatures = { .value = StoreConfig::getDefaultSystemFeatures() },
 };
 
-const StoreConfigT<config::SettingInfo> storeConfigDescriptions = {
+decltype(StoreConfig::schema) StoreConfig::schema = {{
     .pathInfoCacheSize = {
         .name = "path-info-cache-size",
         .description = "Size of the in-memory store path metadata cache.",
@@ -236,12 +236,12 @@ const StoreConfigT<config::SettingInfo> storeConfigDescriptions = {
         // unsuitable to be rendered in the documentation.
         .documentDefault = false,
     },
-};
+}};
 
 StoreConfigT<config::JustValue> parseStoreConfig(const StoreReference::Params & params)
 {
     constexpr auto & defaults = storeConfigDefaults;
-    constexpr auto & descriptions = storeConfigDescriptions;
+    constexpr auto & descriptions = StoreConfig::schema;
 
     return {
         CONFIG_ROW(pathInfoCacheSize),
@@ -497,8 +497,8 @@ StringSet StoreConfig::getDefaultSystemFeatures()
     return res;
 }
 
-Store::Store(const StoreReference::Params & params)
-    : StoreConfig(params)
+Store::Store(const Store::Config & config)
+    : Store::Config(config)
     , state({(size_t) pathInfoCacheSize})
 {
     assertLibStoreInitialized();

diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
@@ -112,16 +112,22 @@ struct StoreConfigT
 
 extern const StoreConfigT<config::JustValue> storeConfigDefaults;
 
-extern const StoreConfigT<config::SettingInfo> storeConfigDescriptions;
-
 StoreConfigT<config::JustValue> parseStoreConfig(const StoreReference::Params &);
 
+struct StoreConfigDescription : StoreConfigT<config::SettingInfo>, StoreDirConfigT<config::SettingInfo>
+{
+};
+
 struct StoreConfig : StoreConfigT<config::JustValue>, StoreDirConfig
 {
     using StoreDirConfig::StoreDirConfig;
 
     StoreConfig() = delete;
 
+    using Description = StoreConfigDescription;
+
+    static const Description schema;
+
     static StringSet getDefaultSystemFeatures();
 
     virtual ~StoreConfig() { }
@@ -147,10 +153,20 @@ struct StoreConfig : StoreConfigT<config::JustValue>, StoreDirConfig
     {
         return std::nullopt;
     }
+
+    /**
+     * Open a store of the type corresponding to this configuration
+     * type.
+     */
+    virtual std::shared_ptr<Store> open() = 0;
 };
 
 class Store : public std::enable_shared_from_this<Store>, public virtual StoreConfig
 {
+public:
+
+    using Config = StoreConfig;
+
 protected:
 
     struct PathInfoCacheValue {
@@ -189,7 +205,7 @@ protected:
 
     std::shared_ptr<NarInfoDiskCache> diskCache;
 
-    Store(const StoreReference::Params & params);
+    Store(const Store::Config & config);
 
 public:
     /**

diff --git a/src/libstore/store-registration.hh b/src/libstore/store-registration.hh
@@ -18,37 +18,38 @@ struct StoreFactory
      * The `authorityPath` parameter is `<authority>/<path>`, or really
      * whatever comes after `<scheme>://` and before `?<query-params>`.
      */
-    std::function<std::shared_ptr<Store>(
-        std::string_view scheme, std::string_view authorityPath, const Store::Params & params)>
-        create;
-    std::function<std::shared_ptr<StoreConfig>()> getConfig;
+    std::function<std::shared_ptr<StoreConfig>(
+        std::string_view scheme, std::string_view authorityPath, const StoreReference::Params & params)>
+        parseConfig;
+    const StoreConfigDescription & configSchema;
 };
 
 struct Implementations
 {
     static std::vector<StoreFactory> * registered;
 
-    template<typename T, typename TConfig>
+    template<typename T>
     static void add()
     {
         if (!registered)
             registered = new std::vector<StoreFactory>();
         StoreFactory factory{
-            .uriSchemes = TConfig::uriSchemes(),
-            .create = ([](auto scheme, auto uri, auto & params) -> std::shared_ptr<Store> {
-                return std::make_shared<T>(scheme, uri, params);
+            .uriSchemes = T::Config::uriSchemes(),
+            .parseConfig = ([](auto scheme, auto uri, auto & params) -> std::shared_ptr<StoreConfig> {
+                return std::make_shared<typename T::Config>(scheme, uri, params);
             }),
-            .getConfig = ([]() -> std::shared_ptr<StoreConfig> { return std::make_shared<TConfig>(StringMap({})); })};
+            .configSchema = T::Config::schema,
+        };
         registered->push_back(factory);
     }
 };
 
-template<typename T, typename TConfig>
+template<typename T>
 struct RegisterStoreImplementation
 {
     RegisterStoreImplementation()
     {
-        Implementations::add<T, TConfig>();
+        Implementations::add<T>();
     }
 };