Merge pull request #6220 from obsidiansystems/log-store

Factor out a `LogStore` interface

11 files changed, 70 insertions, 30 deletions

diff --git a/src/libstore/binary-cache-store.hh b/src/libstore/binary-cache-store.hh
index 9603a8caa..ca538b3cb 100644
--- a/src/libstore/binary-cache-store.hh
+++ b/src/libstore/binary-cache-store.hh
@@ -2,6 +2,7 @@
 
 #include "crypto.hh"
 #include "store-api.hh"
+#include "log-store.hh"
 
 #include "pool.hh"
 
@@ -28,7 +29,9 @@ struct BinaryCacheStoreConfig : virtual StoreConfig
         "other than -1 which we reserve to indicate Nix defaults should be used"};
 };
 
-class BinaryCacheStore : public virtual BinaryCacheStoreConfig, public virtual Store
+class BinaryCacheStore : public virtual BinaryCacheStoreConfig,
+    public virtual Store,
+    public virtual LogStore
 {
 
 private:
diff --git a/src/libstore/build/local-derivation-goal.cc b/src/libstore/build/local-derivation-goal.cc
index a372728f5..4e763e570 100644
--- a/src/libstore/build/local-derivation-goal.cc
+++ b/src/libstore/build/local-derivation-goal.cc
@@ -1340,6 +1340,12 @@ struct RestrictedStore : public virtual RestrictedStoreConfig, public virtual Lo
         next->queryMissing(allowed, willBuild, willSubstitute,
             unknown, downloadSize, narSize);
     }
+
+    virtual std::optional<std::string> getBuildLog(const StorePath & path) override
+    { return std::nullopt; }
+
+    virtual void addBuildLog(const StorePath & path, std::string_view log) override
+    { unsupported("addBuildLog"); }
 };
 
 
diff --git a/src/libstore/daemon.cc b/src/libstore/daemon.cc
index e6760664c..9f21ecf36 100644
--- a/src/libstore/daemon.cc
+++ b/src/libstore/daemon.cc
@@ -3,7 +3,9 @@
 #include "worker-protocol.hh"
 #include "build-result.hh"
 #include "store-api.hh"
+#include "store-cast.hh"
 #include "gc-store.hh"
+#include "log-store.hh"
 #include "path-with-outputs.hh"
 #include "finally.hh"
 #include "archive.hh"
@@ -645,7 +647,7 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
         Path path = absPath(readString(from));
 
         logger->startWork();
-        auto & gcStore = requireGcStore(*store);
+        auto & gcStore = require<GcStore>(*store);
         gcStore.addIndirectRoot(path);
         logger->stopWork();
 
@@ -663,7 +665,7 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
 
     case wopFindRoots: {
         logger->startWork();
-        auto & gcStore = requireGcStore(*store);
+        auto & gcStore = require<GcStore>(*store);
         Roots roots = gcStore.findRoots(!trusted);
         logger->stopWork();
 
@@ -695,7 +697,7 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
         logger->startWork();
         if (options.ignoreLiveness)
             throw Error("you are not allowed to ignore liveness");
-        auto & gcStore = requireGcStore(*store);
+        auto & gcStore = require<GcStore>(*store);
         gcStore.collectGarbage(options, results);
         logger->stopWork();
 
@@ -953,11 +955,12 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
         logger->startWork();
         if (!trusted)
             throw Error("you are not privileged to add logs");
+        auto & logStore = require<LogStore>(*store);
         {
             FramedSource source(from);
             StringSink sink;
             source.drainInto(sink);
-            store->addBuildLog(path, sink.s);
+            logStore.addBuildLog(path, sink.s);
         }
         logger->stopWork();
         to << 1;
diff --git a/src/libstore/gc-store.cc b/src/libstore/gc-store.cc
deleted file mode 100644
index 3dbdec53b..000000000
--- a/src/libstore/gc-store.cc
+++ /dev/null
@@ -1,13 +0,0 @@
-#include "gc-store.hh"
-
-namespace nix {
-
-GcStore & requireGcStore(Store & store)
-{
-    auto * gcStore = dynamic_cast<GcStore *>(&store);
-    if (!gcStore)
-        throw UsageError("Garbage collection not supported by this store");
-    return *gcStore;
-}
-
-}
diff --git a/src/libstore/gc-store.hh b/src/libstore/gc-store.hh
index 829f70dc4..b3cbbad74 100644
--- a/src/libstore/gc-store.hh
+++ b/src/libstore/gc-store.hh
@@ -61,6 +61,8 @@ struct GCResults
 
 struct GcStore : public virtual Store
 {
+    inline static std::string operationName = "Garbage collection";
+
     /* Add an indirect root, which is merely a symlink to `path' from
        /nix/var/nix/gcroots/auto/<hash of `path'>.  `path' is supposed
        to be a symlink to a store path.  The garbage collector will
@@ -79,6 +81,4 @@ struct GcStore : public virtual Store
     virtual void collectGarbage(const GCOptions & options, GCResults & results) = 0;
 };
 
-GcStore & requireGcStore(Store & store);
-
 }
diff --git a/src/libstore/local-fs-store.hh b/src/libstore/local-fs-store.hh
index fbd49dc2c..e6fb3201a 100644
--- a/src/libstore/local-fs-store.hh
+++ b/src/libstore/local-fs-store.hh
@@ -2,6 +2,7 @@
 
 #include "store-api.hh"
 #include "gc-store.hh"
+#include "log-store.hh"
 
 namespace nix {
 
@@ -24,7 +25,10 @@ struct LocalFSStoreConfig : virtual StoreConfig
         "physical path to the Nix store"};
 };
 
-class LocalFSStore : public virtual LocalFSStoreConfig, public virtual Store, virtual GcStore
+class LocalFSStore : public virtual LocalFSStoreConfig,
+    public virtual Store,
+    public virtual GcStore,
+    public virtual LogStore
 {
 public:
 
diff --git a/src/libstore/log-store.hh b/src/libstore/log-store.hh
new file mode 100644
index 000000000..ff1b92e17
--- /dev/null
+++ b/src/libstore/log-store.hh
@@ -0,0 +1,21 @@
+#pragma once
+
+#include "store-api.hh"
+
+
+namespace nix {
+
+struct LogStore : public virtual Store
+{
+    inline static std::string operationName = "Build log storage and retrieval";
+
+    /* Return the build log of the specified store path, if available,
+       or null otherwise. */
+    virtual std::optional<std::string> getBuildLog(const StorePath & path) = 0;
+
+    virtual void addBuildLog(const StorePath & path, std::string_view log) = 0;
+
+    static LogStore & require(Store & store);
+};
+
+}
diff --git a/src/libstore/remote-store.hh b/src/libstore/remote-store.hh
index 9f6f50593..8493be6fc 100644
--- a/src/libstore/remote-store.hh
+++ b/src/libstore/remote-store.hh
@@ -5,6 +5,7 @@
 
 #include "store-api.hh"
 #include "gc-store.hh"
+#include "log-store.hh"
 
 
 namespace nix {
@@ -30,7 +31,10 @@ struct RemoteStoreConfig : virtual StoreConfig
 
 /* FIXME: RemoteStore is a misnomer - should be something like
    DaemonStore. */
-class RemoteStore : public virtual RemoteStoreConfig, public virtual Store, public virtual GcStore
+class RemoteStore : public virtual RemoteStoreConfig,
+    public virtual Store,
+    public virtual GcStore,
+    public virtual LogStore
 {
 public:
 
diff --git a/src/libstore/ssh-store.cc b/src/libstore/ssh-store.cc
index bb03daef4..62daa838c 100644
--- a/src/libstore/ssh-store.cc
+++ b/src/libstore/ssh-store.cc
@@ -52,6 +52,10 @@ public:
     bool sameMachine() override
     { return false; }
 
+    // FIXME extend daemon protocol, move implementation to RemoteStore
+    std::optional<std::string> getBuildLog(const StorePath & path) override
+    { unsupported("getBuildLog"); }
+
 private:
 
     struct Connection : RemoteStore::Connection
diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index e99a3f2cb..635a82a2a 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -605,14 +605,6 @@ public:
      */
     StorePathSet exportReferences(const StorePathSet & storePaths, const StorePathSet & inputPaths);
 
-    /* Return the build log of the specified store path, if available,
-       or null otherwise. */
-    virtual std::optional<std::string> getBuildLog(const StorePath & path)
-    { return std::nullopt; }
-
-    virtual void addBuildLog(const StorePath & path, std::string_view log)
-    { unsupported("addBuildLog"); }
-
     /* Hack to allow long-running processes like hydra-queue-runner to
        occasionally flush their path info cache. */
     void clearPathInfoCache()
diff --git a/src/libstore/store-cast.hh b/src/libstore/store-cast.hh
new file mode 100644
index 000000000..ff62fc359
--- /dev/null
+++ b/src/libstore/store-cast.hh
@@ -0,0 +1,16 @@
+#pragma once
+
+#include "store-api.hh"
+
+namespace nix {
+
+template<typename T>
+T & require(Store & store)
+{
+    auto * castedStore = dynamic_cast<T *>(&store);
+    if (!castedStore)
+        throw UsageError("%s not supported by store '%s'", T::operationName, store.getUri());
+    return *castedStore;
+}
+
+}