diff options
author | Eelco Dolstra <edolstra@gmail.com> | 2017-07-26T15·21+0200 |
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committer | Eelco Dolstra <edolstra@gmail.com> | 2017-07-26T15·29+0200 |
commit | 57b95057311d4dafb948c78889693a98ec349460 (patch) | |
tree | 7757591822f2e1a7bc053fbb27badfa35c5aa5fe /src/nix | |
parent | 4c9ff89c261d84dcc4f88a79654daff2f4790e66 (diff) |
nix search: Add a cache
The package list is now cached in ~/.cache/nix/package-search.json. This gives a substantial speedup to "nix search" queries. For example (on an SSD): First run: (no package search cache, cold page cache) $ time nix search blender Attribute name: nixpkgs.blender Package name: blender Version: 2.78c Description: 3D Creation/Animation/Publishing System real 0m6.516s Second run: (package search cache populated) $ time nix search blender Attribute name: nixpkgs.blender Package name: blender Version: 2.78c Description: 3D Creation/Animation/Publishing System real 0m0.143s
Diffstat (limited to 'src/nix')
-rw-r--r-- | src/nix/search.cc | 78 |
1 files changed, 69 insertions, 9 deletions
diff --git a/src/nix/search.cc b/src/nix/search.cc index 970dcb9834b9..d3e018876a09 100644 --- a/src/nix/search.cc +++ b/src/nix/search.cc @@ -6,8 +6,10 @@ #include "get-drvs.hh" #include "common-args.hh" #include "json.hh" +#include "json-to-value.hh" #include <regex> +#include <fstream> using namespace nix; @@ -25,9 +27,23 @@ struct CmdSearch : SourceExprCommand, MixJSON { std::string re; + bool writeCache = true; + bool useCache = true; + CmdSearch() { expectArg("regex", &re, true); + + mkFlag() + .longName("update-cache") + .shortName('u') + .description("update the package search cache") + .handler([&](Strings ss) { writeCache = true; useCache = false; }); + + mkFlag() + .longName("no-cache") + .description("do not use or update the package search cache") + .handler([&](Strings ss) { writeCache = false; useCache = false; }); } std::string name() override @@ -48,15 +64,18 @@ struct CmdSearch : SourceExprCommand, MixJSON auto state = getEvalState(); - std::function<void(Value *, std::string, bool)> doExpr; - bool first = true; auto jsonOut = json ? std::make_unique<JSONObject>(std::cout, true) : nullptr; auto sToplevel = state->symbols.create("_toplevel"); + auto sRecurse = state->symbols.create("recurseForDerivations"); + + bool fromCache = false; - doExpr = [&](Value * v, std::string attrPath, bool toplevel) { + std::function<void(Value *, std::string, bool, JSONObject *)> doExpr; + + doExpr = [&](Value * v, std::string attrPath, bool toplevel, JSONObject * cache) { debug("at attribute ‘%s’", attrPath); try { @@ -115,23 +134,41 @@ struct CmdSearch : SourceExprCommand, MixJSON hilite(description, descriptionMatch)); } } + + if (cache) { + cache->attr("type", "derivation"); + cache->attr("name", drv.queryName()); + cache->attr("system", drv.querySystem()); + if (description != "") { + auto meta(cache->object("meta")); + meta.attr("description", description); + } + } } else if (v->type == tAttrs) { if (!toplevel) { auto attrs = v->attrs; - Bindings::iterator j = attrs->find(state->symbols.create("recurseForDerivations")); - if (j == attrs->end() || !state->forceBool(*j->value, *j->pos)) return; + Bindings::iterator j = attrs->find(sRecurse); + if (j == attrs->end() || !state->forceBool(*j->value, *j->pos)) { + debug("skip attribute ‘%s’", attrPath); + return; + } } - Bindings::iterator j = v->attrs->find(sToplevel); - bool toplevel2 = j != v->attrs->end() && state->forceBool(*j->value, *j->pos); + bool toplevel2 = false; + if (!fromCache) { + Bindings::iterator j = v->attrs->find(sToplevel); + toplevel2 = j != v->attrs->end() && state->forceBool(*j->value, *j->pos); + } for (auto & i : *v->attrs) { + auto cache2 = + cache ? std::make_unique<JSONObject>(cache->object(i.name)) : nullptr; doExpr(i.value, attrPath == "" ? (std::string) i.name : attrPath + "." + (std::string) i.name, - toplevel2); + toplevel2 || fromCache, cache2 ? cache2.get() : nullptr); } } @@ -144,7 +181,30 @@ struct CmdSearch : SourceExprCommand, MixJSON } }; - doExpr(getSourceExpr(*state), "", true); + Path jsonCacheFileName = getCacheDir() + "/nix/package-search.json"; + + if (useCache && pathExists(jsonCacheFileName)) { + + Value vRoot; + parseJSON(*state, readFile(jsonCacheFileName), vRoot); + + fromCache = true; + + doExpr(&vRoot, "", true, nullptr); + } + + else { + Path tmpFile = fmt("%s.tmp.%d", jsonCacheFileName, getpid()); + + std::ofstream jsonCacheFile(tmpFile); + + auto cache = writeCache ? std::make_unique<JSONObject>(jsonCacheFile, false) : nullptr; + + doExpr(getSourceExpr(*state), "", true, cache.get()); + + if (rename(tmpFile.c_str(), jsonCacheFileName.c_str()) == -1) + throw SysError("cannot rename ‘%s’ to ‘%s’", tmpFile, jsonCacheFileName); + } } }; |