Create new wallet databases as directories rather than files

This change should make it easier for users to make complete backups of wallets
because they can now just back up the specified `-wallet=<path>` path directly,
instead of having to back up the specified path as well as the transaction log
directory (for incompletely flushed wallets).

Another advantage of this change is that if two wallets are located in the same
directory, they will now use their own BerkeleyDB environments instead using a
shared environment. Using a shared environment makes it difficult to manage and
back up wallets separately because transaction log files will contain a mix of
data from all wallets in the environment.

2 files changed, 24 insertions, 14 deletions

diff --git a/test/functional/feature_config_args.py b/test/functional/feature_config_args.py
index 61abba8082..c6cec0596b 100755
--- a/test/functional/feature_config_args.py
+++ b/test/functional/feature_config_args.py
@@ -37,13 +37,13 @@ class ConfArgsTest(BitcoinTestFramework):
         os.mkdir(new_data_dir)
         self.start_node(0, ['-conf='+conf_file, '-wallet=w1'])
         self.stop_node(0)
-        assert os.path.isfile(os.path.join(new_data_dir, 'regtest', 'wallets', 'w1'))
+        assert os.path.exists(os.path.join(new_data_dir, 'regtest', 'wallets', 'w1'))
 
         # Ensure command line argument overrides datadir in conf
         os.mkdir(new_data_dir_2)
         self.nodes[0].datadir = new_data_dir_2
         self.start_node(0, ['-datadir='+new_data_dir_2, '-conf='+conf_file, '-wallet=w2'])
-        assert os.path.isfile(os.path.join(new_data_dir_2, 'regtest', 'wallets', 'w2'))
+        assert os.path.exists(os.path.join(new_data_dir_2, 'regtest', 'wallets', 'w2'))
 
 if __name__ == '__main__':
     ConfArgsTest().main()
diff --git a/test/functional/wallet_multiwallet.py b/test/functional/wallet_multiwallet.py
index 871fc1a151..378c06ee59 100755
--- a/test/functional/wallet_multiwallet.py
+++ b/test/functional/wallet_multiwallet.py
@@ -29,13 +29,24 @@ class MultiWalletTest(BitcoinTestFramework):
         self.stop_nodes()
         assert_equal(os.path.isfile(wallet_dir('wallet.dat')), True)
 
+        # create symlink to verify wallet directory path can be referenced
+        # through symlink
+        os.mkdir(wallet_dir('w7'))
+        os.symlink('w7', wallet_dir('w7_symlink'))
+
+        # rename wallet.dat to make sure plain wallet file paths (as opposed to
+        # directory paths) can be loaded
+        os.rename(wallet_dir("wallet.dat"), wallet_dir("w8"))
+
         # restart node with a mix of wallet names:
         #   w1, w2, w3 - to verify new wallets created when non-existing paths specified
         #   w          - to verify wallet name matching works when one wallet path is prefix of another
         #   sub/w5     - to verify relative wallet path is created correctly
         #   extern/w6  - to verify absolute wallet path is created correctly
-        #   wallet.dat - to verify existing wallet file is loaded correctly
-        wallet_names = ['w1', 'w2', 'w3', 'w', 'sub/w5', os.path.join(self.options.tmpdir, 'extern/w6'), 'wallet.dat']
+        #   w7_symlink - to verify symlinked wallet path is initialized correctly
+        #   w8         - to verify existing wallet file is loaded correctly
+        #   ''         - to verify default wallet file is created correctly
+        wallet_names = ['w1', 'w2', 'w3', 'w', 'sub/w5', os.path.join(self.options.tmpdir, 'extern/w6'), 'w7_symlink', 'w8', '']
         extra_args = ['-wallet={}'.format(n) for n in wallet_names]
         self.start_node(0, extra_args)
         assert_equal(set(node.listwallets()), set(wallet_names))
@@ -43,10 +54,13 @@ class MultiWalletTest(BitcoinTestFramework):
         # check that all requested wallets were created
         self.stop_node(0)
         for wallet_name in wallet_names:
-            assert_equal(os.path.isfile(wallet_dir(wallet_name)), True)
+            if os.path.isdir(wallet_dir(wallet_name)):
+                assert_equal(os.path.isfile(wallet_dir(wallet_name, "wallet.dat")), True)
+            else:
+                assert_equal(os.path.isfile(wallet_dir(wallet_name)), True)
 
         # should not initialize if wallet path can't be created
-        self.assert_start_raises_init_error(0, ['-wallet=wallet.dat/bad'], 'File exists')
+        self.assert_start_raises_init_error(0, ['-wallet=wallet.dat/bad'], 'Not a directory')
 
         self.assert_start_raises_init_error(0, ['-walletdir=wallets'], 'Error: Specified -walletdir "wallets" does not exist')
         self.assert_start_raises_init_error(0, ['-walletdir=wallets'], 'Error: Specified -walletdir "wallets" is a relative path', cwd=data_dir())
@@ -55,17 +69,13 @@ class MultiWalletTest(BitcoinTestFramework):
         # should not initialize if there are duplicate wallets
         self.assert_start_raises_init_error(0, ['-wallet=w1', '-wallet=w1'], 'Error loading wallet w1. Duplicate -wallet filename specified.')
 
-        # should not initialize if wallet file is a directory
-        os.mkdir(wallet_dir('w11'))
-        self.assert_start_raises_init_error(0, ['-wallet=w11'], 'Error loading wallet w11. -wallet filename must be a regular file.')
-
         # should not initialize if one wallet is a copy of another
-        shutil.copyfile(wallet_dir('w2'), wallet_dir('w22'))
-        self.assert_start_raises_init_error(0, ['-wallet=w2', '-wallet=w22'], 'duplicates fileid')
+        shutil.copyfile(wallet_dir('w8'), wallet_dir('w8_copy'))
+        self.assert_start_raises_init_error(0, ['-wallet=w8', '-wallet=w8_copy'], 'duplicates fileid')
 
         # should not initialize if wallet file is a symlink
-        os.symlink(wallet_dir('w1'), wallet_dir('w12'))
-        self.assert_start_raises_init_error(0, ['-wallet=w12'], 'Error loading wallet w12. -wallet filename must be a regular file.')
+        os.symlink('w8', wallet_dir('w8_symlink'))
+        self.assert_start_raises_init_error(0, ['-wallet=w8_symlink'], 'Invalid -wallet path')
 
         # should not initialize if the specified walletdir does not exist
         self.assert_start_raises_init_error(0, ['-walletdir=bad'], 'Error: Specified -walletdir "bad" does not exist')