fix the docs

docs/index.rst

@@ -10,7 +10,6 @@ Welcome to tempsdb's documentation!
    :maxdepth: 2
    :caption: Contents:
 
-   time-series
    usage
    exceptions
 

docs/time-series.rst

-Time series
-===========
-
-The name of the series must be a valid name for a directory on your filesystem.

docs/usage.rst

@@ -6,6 +6,10 @@ Start off by instantiating an object
 .. autoclass:: tempsdb.database.Database
     :members:
 
+You can create new databases via
+
+.. autofunction:: tempsdb.database.create_database
+
 Then you can create and retrieve particular series:
 
 .. autoclass:: tempsdb.series.TimeSeries

tempsdb/database.pxd

@@ -9,3 +9,6 @@ cdef class Database:
 
     cpdef void close(self)
     cpdef TimeSeries get_series(self, str name)
+
+cpdef Database create_database(str path)
+

tempsdb/database.pyx

 import os
 import threading
 
-from tempsdb.exceptions import DoesNotExist
+from tempsdb.exceptions import DoesNotExist, AlreadyExists
 from .series cimport TimeSeries
 
 
 cdef class Database:
     """
     A basic TempsDB object.
+
+    :param path: path to the directory with the database
     """
     def __init__(self, path: str):
         self.path = path
@@ -16,16 +18,33 @@ cdef class Database:
         self.lock = threading.Lock()
 
     cpdef TimeSeries get_series(self, name: str):
-        cdef TimeSeries result
+        """
+        Load and return an existing series
+        
+        :param name: name of the series
+        :type name: str
+        :return: a loaded time series
+        :rtype: TimeSeries
+        :raises DoesNotExist: series does not exist
+        """
+        cdef:
+            TimeSeries result
+            str path
         if name in self.open_series:
             result = self.open_series[name]
         else:
+            path = os.path.join(self.path, name)
             with self.lock:
-                if not os.path.isdir(os.path.join(self.path, name)):
+                # Check a second time due to the lock
+                if name in self.open_series:
+                    return self.open_series[name]
+                if not os.path.isdir(path):
                     raise DoesNotExist('series %s does not exist' % (name, ))
-                self.open_series[name] = result = TimeSeries(self, name)
+                self.open_series[name] = result = TimeSeries(path)
         return result
 
+    def __del__(self):
+        self.close()
 
     cpdef void close(self):
         """
@@ -37,3 +56,19 @@ cdef class Database:
         for series in self.open_series.values():
             series.close()
         self.closed = True
+
+
+cpdef Database create_database(str path):
+    """
+    Creates a new, empty database
+    
+    :param path: path where the DB directory will be put
+    :type path: str
+    :return: a Database object
+    :rtype: Database
+    :raises AlreadyExists: the directory exists
+    """
+    if os.path.exists(path):
+        raise AlreadyExists('directory already exists')
+    os.mkdir(path)
+    return Database(path)