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-rw-r--r--src/nix/flake.cc717
1 files changed, 717 insertions, 0 deletions
diff --git a/src/nix/flake.cc b/src/nix/flake.cc
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index 000000000..e79f4129a
--- /dev/null
+++ b/src/nix/flake.cc
@@ -0,0 +1,717 @@
+#include "command.hh"
+#include "common-args.hh"
+#include "shared.hh"
+#include "progress-bar.hh"
+#include "eval.hh"
+#include "eval-inline.hh"
+#include "flake/flake.hh"
+#include "get-drvs.hh"
+#include "store-api.hh"
+#include "derivations.hh"
+#include "attr-path.hh"
+#include "fetchers.hh"
+#include "registry.hh"
+#include "json.hh"
+
+#include <nlohmann/json.hpp>
+#include <queue>
+#include <iomanip>
+
+using namespace nix;
+using namespace nix::flake;
+
+class FlakeCommand : virtual Args, public EvalCommand, public MixFlakeOptions
+{
+ std::string flakeUrl = ".";
+
+public:
+
+ FlakeCommand()
+ {
+ expectArg("flake-url", &flakeUrl, true);
+ }
+
+ FlakeRef getFlakeRef()
+ {
+ return parseFlakeRef(flakeUrl, absPath(".")); //FIXME
+ }
+
+ Flake getFlake()
+ {
+ auto evalState = getEvalState();
+ return flake::getFlake(*evalState, getFlakeRef(), lockFlags.useRegistries);
+ }
+
+ LockedFlake lockFlake()
+ {
+ return flake::lockFlake(*getEvalState(), getFlakeRef(), lockFlags);
+ }
+};
+
+struct CmdFlakeList : EvalCommand
+{
+ std::string description() override
+ {
+ return "list available Nix flakes";
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ using namespace fetchers;
+
+ auto registries = getRegistries(store);
+
+ stopProgressBar();
+
+ for (auto & registry : registries) {
+ for (auto & entry : registry->entries) {
+ // FIXME: format nicely
+ std::cout << fmt("%s %s %s\n",
+ registry->type == Registry::Flag ? "flags " :
+ registry->type == Registry::User ? "user " :
+ registry->type == Registry::System ? "system" :
+ "global",
+ entry.from->to_string(),
+ entry.to->to_string());
+ }
+ }
+ }
+};
+
+static void printFlakeInfo(const Store & store, const Flake & flake)
+{
+ std::cout << fmt("Resolved URL: %s\n", flake.resolvedRef.to_string());
+ std::cout << fmt("Locked URL: %s\n", flake.lockedRef.to_string());
+ std::cout << fmt("Edition: %s\n", flake.edition);
+ if (flake.description)
+ std::cout << fmt("Description: %s\n", *flake.description);
+ std::cout << fmt("Path: %s\n", store.printStorePath(flake.sourceInfo->storePath));
+ if (auto rev = flake.lockedRef.input->getRev())
+ std::cout << fmt("Revision: %s\n", rev->to_string(Base16, false));
+ if (flake.sourceInfo->info.revCount)
+ std::cout << fmt("Revisions: %s\n", *flake.sourceInfo->info.revCount);
+ if (flake.sourceInfo->info.lastModified)
+ std::cout << fmt("Last modified: %s\n",
+ std::put_time(std::localtime(&*flake.sourceInfo->info.lastModified), "%F %T"));
+}
+
+static nlohmann::json flakeToJson(const Store & store, const Flake & flake)
+{
+ nlohmann::json j;
+ if (flake.description)
+ j["description"] = *flake.description;
+ j["edition"] = flake.edition;
+ j["originalUrl"] = flake.originalRef.to_string();
+ j["original"] = attrsToJson(flake.originalRef.toAttrs());
+ j["resolvedUrl"] = flake.resolvedRef.to_string();
+ j["resolved"] = attrsToJson(flake.resolvedRef.toAttrs());
+ j["url"] = flake.lockedRef.to_string(); // FIXME: rename to lockedUrl
+ j["locked"] = attrsToJson(flake.lockedRef.toAttrs());
+ j["info"] = flake.sourceInfo->info.toJson();
+ if (auto rev = flake.lockedRef.input->getRev())
+ j["revision"] = rev->to_string(Base16, false);
+ if (flake.sourceInfo->info.revCount)
+ j["revCount"] = *flake.sourceInfo->info.revCount;
+ if (flake.sourceInfo->info.lastModified)
+ j["lastModified"] = *flake.sourceInfo->info.lastModified;
+ j["path"] = store.printStorePath(flake.sourceInfo->storePath);
+ return j;
+}
+
+struct CmdFlakeUpdate : FlakeCommand
+{
+ std::string description() override
+ {
+ return "update flake lock file";
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ /* Use --refresh by default for 'nix flake update'. */
+ settings.tarballTtl = 0;
+
+ lockFlake();
+ }
+};
+
+static void enumerateOutputs(EvalState & state, Value & vFlake,
+ std::function<void(const std::string & name, Value & vProvide, const Pos & pos)> callback)
+{
+ state.forceAttrs(vFlake);
+
+ auto aOutputs = vFlake.attrs->get(state.symbols.create("outputs"));
+ assert(aOutputs);
+
+ state.forceAttrs(*aOutputs->value);
+
+ for (auto & attr : *aOutputs->value->attrs)
+ callback(attr.name, *attr.value, *attr.pos);
+}
+
+struct CmdFlakeInfo : FlakeCommand, MixJSON
+{
+ std::string description() override
+ {
+ return "list info about a given flake";
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ auto flake = getFlake();
+ stopProgressBar();
+
+ if (json) {
+ auto json = flakeToJson(*store, flake);
+ std::cout << json.dump() << std::endl;
+ } else
+ printFlakeInfo(*store, flake);
+ }
+};
+
+struct CmdFlakeListInputs : FlakeCommand, MixJSON
+{
+ std::string description() override
+ {
+ return "list flake inputs";
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ auto flake = lockFlake();
+
+ stopProgressBar();
+
+ if (json)
+ std::cout << flake.lockFile.toJson() << "\n";
+ else {
+ std::cout << fmt("%s\n", flake.flake.lockedRef);
+
+ std::function<void(const Node & node, const std::string & prefix)> recurse;
+
+ recurse = [&](const Node & node, const std::string & prefix)
+ {
+ for (const auto & [i, input] : enumerate(node.inputs)) {
+ //auto tree2 = tree.child(i + 1 == inputs.inputs.size());
+ bool last = i + 1 == node.inputs.size();
+ std::cout << fmt("%s" ANSI_BOLD "%s" ANSI_NORMAL ": %s\n",
+ prefix + (last ? treeLast : treeConn), input.first,
+ std::dynamic_pointer_cast<const LockedNode>(input.second)->lockedRef);
+ recurse(*input.second, prefix + (last ? treeNull : treeLine));
+ }
+ };
+
+ recurse(*flake.lockFile.root, "");
+ }
+ }
+};
+
+struct CmdFlakeCheck : FlakeCommand
+{
+ bool build = true;
+
+ CmdFlakeCheck()
+ {
+ mkFlag()
+ .longName("no-build")
+ .description("do not build checks")
+ .set(&build, false);
+ }
+
+ std::string description() override
+ {
+ return "check whether the flake evaluates and run its tests";
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ settings.readOnlyMode = !build;
+
+ auto state = getEvalState();
+ auto flake = lockFlake();
+
+ auto checkSystemName = [&](const std::string & system, const Pos & pos) {
+ // FIXME: what's the format of "system"?
+ if (system.find('-') == std::string::npos)
+ throw Error("'%s' is not a valid system type, at %s", system, pos);
+ };
+
+ auto checkDerivation = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ auto drvInfo = getDerivation(*state, v, false);
+ if (!drvInfo)
+ throw Error("flake attribute '%s' is not a derivation", attrPath);
+ // FIXME: check meta attributes
+ return store->parseStorePath(drvInfo->queryDrvPath());
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the derivation '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ std::vector<StorePathWithOutputs> drvPaths;
+
+ auto checkApp = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ auto app = App(*state, v);
+ for (auto & i : app.context) {
+ auto [drvPathS, outputName] = decodeContext(i);
+ auto drvPath = store->parseStorePath(drvPathS);
+ if (!outputName.empty() && drvPath.isDerivation())
+ drvPaths.emplace_back(drvPath);
+ }
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the app definition '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ auto checkOverlay = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ state->forceValue(v, pos);
+ if (v.type != tLambda || v.lambda.fun->matchAttrs || std::string(v.lambda.fun->arg) != "final")
+ throw Error("overlay does not take an argument named 'final'");
+ auto body = dynamic_cast<ExprLambda *>(v.lambda.fun->body);
+ if (!body || body->matchAttrs || std::string(body->arg) != "prev")
+ throw Error("overlay does not take an argument named 'prev'");
+ // FIXME: if we have a 'nixpkgs' input, use it to
+ // evaluate the overlay.
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the overlay '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ auto checkModule = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ state->forceValue(v, pos);
+ if (v.type == tLambda) {
+ if (!v.lambda.fun->matchAttrs || !v.lambda.fun->formals->ellipsis)
+ throw Error("module must match an open attribute set ('{ config, ... }')");
+ } else if (v.type == tAttrs) {
+ for (auto & attr : *v.attrs)
+ try {
+ state->forceValue(*attr.value, *attr.pos);
+ } catch (Error & e) {
+ e.addPrefix(fmt("while evaluating the option '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attr.name, *attr.pos));
+ throw;
+ }
+ } else
+ throw Error("module must be a function or an attribute set");
+ // FIXME: if we have a 'nixpkgs' input, use it to
+ // check the module.
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the NixOS module '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ std::function<void(const std::string & attrPath, Value & v, const Pos & pos)> checkHydraJobs;
+
+ checkHydraJobs = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ state->forceAttrs(v, pos);
+
+ if (state->isDerivation(v))
+ throw Error("jobset should not be a derivation at top-level");
+
+ for (auto & attr : *v.attrs) {
+ state->forceAttrs(*attr.value, *attr.pos);
+ if (!state->isDerivation(*attr.value))
+ checkHydraJobs(attrPath + "." + (std::string) attr.name,
+ *attr.value, *attr.pos);
+ }
+
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the Hydra jobset '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ auto checkNixOSConfiguration = [&](const std::string & attrPath, Value & v, const Pos & pos) {
+ try {
+ Activity act(*logger, lvlChatty, actUnknown,
+ fmt("checking NixOS configuration '%s'", attrPath));
+ Bindings & bindings(*state->allocBindings(0));
+ auto vToplevel = findAlongAttrPath(*state, "config.system.build.toplevel", bindings, v).first;
+ state->forceAttrs(*vToplevel, pos);
+ if (!state->isDerivation(*vToplevel))
+ throw Error("attribute 'config.system.build.toplevel' is not a derivation");
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking the NixOS configuration '" ANSI_BOLD "%s" ANSI_NORMAL "' at %s:\n", attrPath, pos));
+ throw;
+ }
+ };
+
+ {
+ Activity act(*logger, lvlInfo, actUnknown, "evaluating flake");
+
+ auto vFlake = state->allocValue();
+ flake::callFlake(*state, flake, *vFlake);
+
+ enumerateOutputs(*state,
+ *vFlake,
+ [&](const std::string & name, Value & vOutput, const Pos & pos) {
+ Activity act(*logger, lvlChatty, actUnknown,
+ fmt("checking flake output '%s'", name));
+
+ try {
+ state->forceValue(vOutput, pos);
+
+ if (name == "checks") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ state->forceAttrs(*attr.value, *attr.pos);
+ for (auto & attr2 : *attr.value->attrs) {
+ auto drvPath = checkDerivation(
+ fmt("%s.%s.%s", name, attr.name, attr2.name),
+ *attr2.value, *attr2.pos);
+ if ((std::string) attr.name == settings.thisSystem.get())
+ drvPaths.emplace_back(drvPath);
+ }
+ }
+ }
+
+ else if (name == "packages") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ state->forceAttrs(*attr.value, *attr.pos);
+ for (auto & attr2 : *attr.value->attrs)
+ checkDerivation(
+ fmt("%s.%s.%s", name, attr.name, attr2.name),
+ *attr2.value, *attr2.pos);
+ }
+ }
+
+ else if (name == "apps") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ state->forceAttrs(*attr.value, *attr.pos);
+ for (auto & attr2 : *attr.value->attrs)
+ checkApp(
+ fmt("%s.%s.%s", name, attr.name, attr2.name),
+ *attr2.value, *attr2.pos);
+ }
+ }
+
+ else if (name == "defaultPackage" || name == "devShell") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ checkDerivation(
+ fmt("%s.%s", name, attr.name),
+ *attr.value, *attr.pos);
+ }
+ }
+
+ else if (name == "defaultApp") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ checkApp(
+ fmt("%s.%s", name, attr.name),
+ *attr.value, *attr.pos);
+ }
+ }
+
+ else if (name == "legacyPackages") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs) {
+ checkSystemName(attr.name, *attr.pos);
+ // FIXME: do getDerivations?
+ }
+ }
+
+ else if (name == "overlay")
+ checkOverlay(name, vOutput, pos);
+
+ else if (name == "overlays") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs)
+ checkOverlay(fmt("%s.%s", name, attr.name),
+ *attr.value, *attr.pos);
+ }
+
+ else if (name == "nixosModule")
+ checkModule(name, vOutput, pos);
+
+ else if (name == "nixosModules") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs)
+ checkModule(fmt("%s.%s", name, attr.name),
+ *attr.value, *attr.pos);
+ }
+
+ else if (name == "nixosConfigurations") {
+ state->forceAttrs(vOutput, pos);
+ for (auto & attr : *vOutput.attrs)
+ checkNixOSConfiguration(fmt("%s.%s", name, attr.name),
+ *attr.value, *attr.pos);
+ }
+
+ else if (name == "hydraJobs")
+ checkHydraJobs(name, vOutput, pos);
+
+ else
+ warn("unknown flake output '%s'", name);
+
+ } catch (Error & e) {
+ e.addPrefix(fmt("while checking flake output '" ANSI_BOLD "%s" ANSI_NORMAL "':\n", name));
+ throw;
+ }
+ });
+ }
+
+ if (build && !drvPaths.empty()) {
+ Activity act(*logger, lvlInfo, actUnknown, "running flake checks");
+ store->buildPaths(drvPaths);
+ }
+ }
+};
+
+struct CmdFlakeAdd : MixEvalArgs, Command
+{
+ std::string fromUrl, toUrl;
+
+ std::string description() override
+ {
+ return "upsert flake in user flake registry";
+ }
+
+ CmdFlakeAdd()
+ {
+ expectArg("from-url", &fromUrl);
+ expectArg("to-url", &toUrl);
+ }
+
+ void run() override
+ {
+ auto fromRef = parseFlakeRef(fromUrl);
+ auto toRef = parseFlakeRef(toUrl);
+ fetchers::Attrs extraAttrs;
+ if (toRef.subdir != "") extraAttrs["dir"] = toRef.subdir;
+ auto userRegistry = fetchers::getUserRegistry();
+ userRegistry->remove(fromRef.input);
+ userRegistry->add(fromRef.input, toRef.input, extraAttrs);
+ userRegistry->write(fetchers::getUserRegistryPath());
+ }
+};
+
+struct CmdFlakeRemove : virtual Args, MixEvalArgs, Command
+{
+ std::string url;
+
+ std::string description() override
+ {
+ return "remove flake from user flake registry";
+ }
+
+ CmdFlakeRemove()
+ {
+ expectArg("url", &url);
+ }
+
+ void run() override
+ {
+ auto userRegistry = fetchers::getUserRegistry();
+ userRegistry->remove(parseFlakeRef(url).input);
+ userRegistry->write(fetchers::getUserRegistryPath());
+ }
+};
+
+struct CmdFlakePin : virtual Args, EvalCommand
+{
+ std::string url;
+
+ std::string description() override
+ {
+ return "pin a flake to its current version in user flake registry";
+ }
+
+ CmdFlakePin()
+ {
+ expectArg("url", &url);
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ auto ref = parseFlakeRef(url);
+ auto userRegistry = fetchers::getUserRegistry();
+ userRegistry->remove(ref.input);
+ auto [tree, resolved] = ref.resolve(store).input->fetchTree(store);
+ fetchers::Attrs extraAttrs;
+ if (ref.subdir != "") extraAttrs["dir"] = ref.subdir;
+ userRegistry->add(ref.input, resolved, extraAttrs);
+ }
+};
+
+struct CmdFlakeInit : virtual Args, Command
+{
+ std::string description() override
+ {
+ return "create a skeleton 'flake.nix' file in the current directory";
+ }
+
+ void run() override
+ {
+ Path flakeDir = absPath(".");
+
+ if (!pathExists(flakeDir + "/.git"))
+ throw Error("the directory '%s' is not a Git repository", flakeDir);
+
+ Path flakePath = flakeDir + "/flake.nix";
+
+ if (pathExists(flakePath))
+ throw Error("file '%s' already exists", flakePath);
+
+ writeFile(flakePath,
+#include "flake-template.nix.gen.hh"
+ );
+ }
+};
+
+struct CmdFlakeClone : FlakeCommand
+{
+ Path destDir;
+
+ std::string description() override
+ {
+ return "clone flake repository";
+ }
+
+ CmdFlakeClone()
+ {
+ mkFlag()
+ .shortName('f')
+ .longName("dest")
+ .label("path")
+ .description("destination path")
+ .dest(&destDir);
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ if (destDir.empty())
+ throw Error("missing flag '--dest'");
+
+ getFlakeRef().resolve(store).input->clone(destDir);
+ }
+};
+
+struct CmdFlakeArchive : FlakeCommand, MixJSON, MixDryRun
+{
+ std::string dstUri;
+
+ CmdFlakeArchive()
+ {
+ mkFlag()
+ .longName("to")
+ .labels({"store-uri"})
+ .description("URI of the destination Nix store")
+ .dest(&dstUri);
+ }
+
+ std::string description() override
+ {
+ return "copy a flake and all its inputs to a store";
+ }
+
+ Examples examples() override
+ {
+ return {
+ Example{
+ "To copy the dwarffs flake and its dependencies to a binary cache:",
+ "nix flake archive --to file:///tmp/my-cache dwarffs"
+ },
+ Example{
+ "To fetch the dwarffs flake and its dependencies to the local Nix store:",
+ "nix flake archive dwarffs"
+ },
+ Example{
+ "To print the store paths of the flake sources of NixOps without fetching them:",
+ "nix flake archive --json --dry-run nixops"
+ },
+ };
+ }
+
+ void run(nix::ref<nix::Store> store) override
+ {
+ auto flake = lockFlake();
+
+ auto jsonRoot = json ? std::optional<JSONObject>(std::cout) : std::nullopt;
+
+ StorePathSet sources;
+
+ sources.insert(flake.flake.sourceInfo->storePath.clone());
+ if (jsonRoot)
+ jsonRoot->attr("path", store->printStorePath(flake.flake.sourceInfo->storePath));
+
+ // FIXME: use graph output, handle cycles.
+ std::function<void(const Node & node, std::optional<JSONObject> & jsonObj)> traverse;
+ traverse = [&](const Node & node, std::optional<JSONObject> & jsonObj)
+ {
+ auto jsonObj2 = jsonObj ? jsonObj->object("inputs") : std::optional<JSONObject>();
+ for (auto & input : node.inputs) {
+ auto lockedInput = std::dynamic_pointer_cast<const LockedNode>(input.second);
+ assert(lockedInput);
+ auto jsonObj3 = jsonObj2 ? jsonObj2->object(input.first) : std::optional<JSONObject>();
+ if (!dryRun)
+ lockedInput->lockedRef.input->fetchTree(store);
+ auto storePath = lockedInput->computeStorePath(*store);
+ if (jsonObj3)
+ jsonObj3->attr("path", store->printStorePath(storePath));
+ sources.insert(std::move(storePath));
+ traverse(*lockedInput, jsonObj3);
+ }
+ };
+
+ traverse(*flake.lockFile.root, jsonRoot);
+
+ if (!dryRun && !dstUri.empty()) {
+ ref<Store> dstStore = dstUri.empty() ? openStore() : openStore(dstUri);
+ copyPaths(store, dstStore, sources);
+ }
+ }
+};
+
+struct CmdFlake : virtual MultiCommand, virtual Command
+{
+ CmdFlake()
+ : MultiCommand({
+ {"list", []() { return make_ref<CmdFlakeList>(); }},
+ {"update", []() { return make_ref<CmdFlakeUpdate>(); }},
+ {"info", []() { return make_ref<CmdFlakeInfo>(); }},
+ {"list-inputs", []() { return make_ref<CmdFlakeListInputs>(); }},
+ {"check", []() { return make_ref<CmdFlakeCheck>(); }},
+ {"add", []() { return make_ref<CmdFlakeAdd>(); }},
+ {"remove", []() { return make_ref<CmdFlakeRemove>(); }},
+ {"pin", []() { return make_ref<CmdFlakePin>(); }},
+ {"init", []() { return make_ref<CmdFlakeInit>(); }},
+ {"clone", []() { return make_ref<CmdFlakeClone>(); }},
+ {"archive", []() { return make_ref<CmdFlakeArchive>(); }},
+ })
+ {
+ }
+
+ std::string description() override
+ {
+ return "manage Nix flakes";
+ }
+
+ void run() override
+ {
+ if (!command)
+ throw UsageError("'nix flake' requires a sub-command.");
+ command->prepare();
+ command->run();
+ }
+
+ void printHelp(const string & programName, std::ostream & out) override
+ {
+ MultiCommand::printHelp(programName, out);
+ }
+};
+
+static auto r1 = registerCommand<CmdFlake>("flake");