Allow activities to be nested

In particular, this allows more relevant activities ("substituting X")
to supersede inferior ones ("downloading X").

4 files changed, 13 insertions, 6 deletions

diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index 77dee2914677..cb67d7a6c144 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -2407,14 +2407,14 @@ struct BuilderLogger : Logger
     }
 
     void startActivity(ActivityId act, ActivityType type,
-        const std::string & s, const Fields & fields) override
+        const std::string & s, const Fields & fields, ActivityId parent) override
     {
         nlohmann::json json;
         json["action"] = "start";
         json["id"] = act;
         json["type"] = type;
         json["text"] = s;
-        // FIXME: handle fields
+        // FIXME: handle fields, parent
         log(lvlError, "@nix " + json.dump());
     }
 
@@ -3313,7 +3313,7 @@ void DerivationGoal::flushLine()
                 if (type == actDownload)
                     builderActivities.emplace(std::piecewise_construct,
                         std::forward_as_tuple(json["id"]),
-                        std::forward_as_tuple(*logger, type, json["text"]));
+                        std::forward_as_tuple(*logger, type, json["text"], Logger::Fields{}, act->id));
             }
 
             else if (action == "stop")
@@ -3655,6 +3655,9 @@ void SubstitutionGoal::tryToRun()
             /* Wake up the worker loop when we're done. */
             Finally updateStats([this]() { outPipe.writeSide = -1; });
 
+            Activity act(*logger, actSubstitute, "", Logger::Fields{storePath, sub->getUri()});
+            PushActivity pact(act.id);
+
             copyStorePath(ref<Store>(sub), ref<Store>(worker.store.shared_from_this()),
                 storePath, repair);
 
diff --git a/src/libstore/download.cc b/src/libstore/download.cc
index 71b720a3b59e..a20999176778 100644
--- a/src/libstore/download.cc
+++ b/src/libstore/download.cc
@@ -85,7 +85,7 @@ struct CurlDownloader : public Downloader
         DownloadItem(CurlDownloader & downloader, const DownloadRequest & request)
             : downloader(downloader)
             , request(request)
-            , act(*logger, actDownload, fmt("downloading '%s'", request.uri))
+            , act(*logger, actDownload, fmt("downloading '%s'", request.uri), {}, request.parentAct)
         {
             if (!request.expectedETag.empty())
                 requestHeaders = curl_slist_append(requestHeaders, ("If-None-Match: " + request.expectedETag).c_str());
diff --git a/src/libstore/download.hh b/src/libstore/download.hh
index 7d8982d64c4c..752bf3723cfc 100644
--- a/src/libstore/download.hh
+++ b/src/libstore/download.hh
@@ -16,8 +16,10 @@ struct DownloadRequest
     bool head = false;
     size_t tries = 5;
     unsigned int baseRetryTimeMs = 250;
+    ActivityId parentAct;
 
-    DownloadRequest(const std::string & uri) : uri(uri) { }
+    DownloadRequest(const std::string & uri)
+        : uri(uri), parentAct(curActivity) { }
 };
 
 struct DownloadResult
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index f520210615a3..f07376852711 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -565,7 +565,9 @@ void Store::buildPaths(const PathSet & paths, BuildMode buildMode)
 void copyStorePath(ref<Store> srcStore, ref<Store> dstStore,
     const Path & storePath, RepairFlag repair, CheckSigsFlag checkSigs)
 {
-    Activity act(*logger, actCopyPath, fmt("copying path '%s'", storePath));
+    Activity act(*logger, actCopyPath, fmt("copying path '%s'", storePath),
+        {storePath, srcStore->getUri(), dstStore->getUri()});
+    PushActivity pact(act.id);
 
     auto info = srcStore->queryPathInfo(storePath);