store: support in-memory database

For testing, this is faster / and doesn't pollute the file system.

lib/mu-store.cc

@@ -106,7 +106,7 @@ struct Store::Private {
 
 #define LOCKED std::lock_guard<std::mutex> l(lock_);
 
-        enum struct XapianOpts {ReadOnly, Open, CreateOverwrite };
+        enum struct XapianOpts {ReadOnly, Open, CreateOverwrite, InMemory };
 
         Private (const std::string& path, bool readonly):
                 read_only_{readonly},
@@ -128,6 +128,14 @@ struct Store::Private {
                 writable_db().begin_transaction();
         }
 
+        Private (const std::string& root_maildir,
+                 const StringVec& personal_addresses, const Store::Config& conf):
+                read_only_{false},
+                db_{make_xapian_db("", XapianOpts::InMemory)},
+                mdata_{init_metadata(conf, "", root_maildir, personal_addresses)},
+                contacts_{"", mdata_.personal_addresses} {
+        }
+
         ~Private() try {
                 g_debug("closing store @ %s", mdata_.database_path.c_str());
                 if (!read_only_) {
@@ -145,6 +153,8 @@ struct Store::Private {
                         return std::make_unique<Xapian::WritableDatabase>(db_path, Xapian::DB_OPEN);
                 case XapianOpts::CreateOverwrite:
                         return std::make_unique<Xapian::WritableDatabase>(db_path, Xapian::DB_CREATE_OR_OVERWRITE);
+                case XapianOpts::InMemory:
+                        return std::make_unique<Xapian::WritableDatabase>(std::string{}, Xapian::DB_BACKEND_INMEMORY);
                 default:
                         throw std::logic_error ("invalid xapian options");
                 }
@@ -174,6 +184,8 @@ struct Store::Private {
         void commit () try {
                 g_debug("committing %zu modification(s)", dirtiness_);
                 dirtiness_      = 0;
+                if (mdata_.in_memory)
+                        return; // not supported in the in-memory backend.
                 writable_db().commit_transaction();
                 writable_db().begin_transaction();
         } MU_XAPIAN_CATCH_BLOCK;
@@ -200,6 +212,7 @@ struct Store::Private {
 
                 mdata.batch_size          = ::atoll(db().get_metadata(BatchSizeKey).c_str());
                 mdata.max_message_size    = ::atoll(db().get_metadata(MaxMessageSizeKey).c_str());
+                mdata.in_memory           = db_path.empty();
 
                 mdata.root_maildir       = db().get_metadata(RootMaildirKey);
                 mdata.personal_addresses = Mu::split(db().get_metadata(PersonalAddressesKey),",");
@@ -288,6 +301,13 @@ Store::Store (const std::string& path, const std::string& maildir,
         priv_{std::make_unique<Private>(path, maildir, personal_addresses, conf)}
 {}
 
+
+Store::Store (const std::string& maildir,
+              const StringVec& personal_addresses, const Config& conf):
+        priv_{std::make_unique<Private>(maildir, personal_addresses, conf)}
+{}
+
+
 Store::~Store() = default;
 
 const Store::Metadata&
@@ -307,7 +327,6 @@ const Xapian::Database&
 Store::database() const
 {
         return priv_->db();
-
 }
 
 Xapian::WritableDatabase&
@@ -370,7 +389,6 @@ maildir_from_path (const std::string& root, const std::string& path)
         return mdir;
 }
 
-
 unsigned
 Store::add_message (const std::string& path)
 {
@@ -395,7 +413,6 @@ Store::add_message (const std::string& path)
 	return docid;
 }
 
-
 bool
 Store::update_message (MuMsg *msg, unsigned docid)
 {
@@ -573,9 +590,6 @@ Store::for_each_term (const std::string& field, Store::ForEachTermFunc func) con
         return n;
 }
 
-
-
-
 void
 Store::commit () try
 {

lib/mu-store.hh

@@ -1,5 +1,5 @@
 /*
-** Copyright (C) 2020 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+** Copyright (C) 2021 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
 ** This program is free software; you can redistribute it and/or modify it
 ** under the terms of the GNU General Public License as published by the
@@ -69,6 +69,16 @@ public:
         Store (const std::string& path, const std::string& maildir,
                const StringVec& personal_addresses, const Config& conf);
 
+        /**
+         * Construct an in-memory, writeable store for testing
+         *
+         * @param maildir maildir to use for this store
+         * @param personal_addresses addresses that should be recognized as
+         * 'personal' for identifying personal messages.
+         */
+        Store (const std::string& maildir,
+               const StringVec& personal_addresses, const Config& conf);
+
         /**
          * DTOR
          */
@@ -81,6 +91,7 @@ public:
 
                 bool        read_only;          /**< Is the database opened read-only? */
                 size_t      batch_size;         /**< Maximum database transaction batch size */
+                bool        in_memory;          /**< Is this an in-memory database (for testing)?*/
 
                 std::string root_maildir;       /**<  Absolute path to the top-level maildir */
 
@@ -117,7 +128,6 @@ public:
          */
         Xapian::WritableDatabase& writable_database();
 
-
         /**
          * Get the Indexer associated with this store. It is an error to call
          * this on a read-only store.

lib/test-mu-store.cc

@@ -79,14 +79,46 @@ test_store_add_count_remove ()
 }
 
 
+static void
+test_store_add_count_remove_in_memory ()
+{
+	Mu::Store store{MuTestMaildir, {}, {}};
+
+        g_assert_true (store.metadata().in_memory);
+
+        const auto id1 = store.add_message(MuTestMaildir + "/cur/1283599333.1840_11.cthulhu!2,");
+
+        g_assert_cmpuint(id1, !=, Mu::Store::InvalidId);
+
+        g_assert_cmpuint(store.size(), ==, 1);
+        g_assert_true(store.contains_message(MuTestMaildir + "/cur/1283599333.1840_11.cthulhu!2,"));
+
+        g_assert_cmpuint(store.add_message(MuTestMaildir2 + "/bar/cur/mail3"),
+                         !=, Mu::Store::InvalidId);
+
+        g_assert_cmpuint(store.size(), ==, 2);
+        g_assert_true(store.contains_message(MuTestMaildir2 + "/bar/cur/mail3"));
+
+        store.remove_message(id1);
+        g_assert_cmpuint(store.size(), ==, 1);
+        g_assert_false(store.contains_message(MuTestMaildir + "/cur/1283599333.1840_11.cthulhu!2,"));
+
+        store.remove_message (MuTestMaildir2 + "/bar/cur/mail3");
+        g_assert_true(store.empty());
+        g_assert_false(store.contains_message(MuTestMaildir2 + "/bar/cur/mail3"));
+}
+
+
+
 int
 main (int argc, char *argv[])
 {
 	g_test_init (&argc, &argv, NULL);
 
 	/* mu_runtime_init/uninit */
-	g_test_add_func ("/mu-store/ctor-dtor", test_store_ctor_dtor);
+	g_test_add_func ("/store/ctor-dtor", test_store_ctor_dtor);
-	g_test_add_func ("/mu-store/add-count-remove", test_store_add_count_remove);
+	g_test_add_func ("/store/add-count-remove", test_store_add_count_remove);
+        g_test_add_func ("/store/in-memory/add-count-remove", test_store_add_count_remove_in_memory);
 
 	// if (!g_test_verbose())
 	// 	g_log_set_handler (NULL,