Implement context manager in database

pcigale/analysis_modules/psum.py

@@ -177,12 +177,11 @@ class Psum(AnalysisModule):
                        if not name.endswith('_err')]
         transmission = {}
         effective_wavelength = {}
-        base = Database()
-        for name in filter_list:
-            filt = base.get_filter(name)
-            transmission[name] = filt.trans_table
-            effective_wavelength[name] = filt.effective_wavelength
-        base.close()
+        with Database() as base:
+            for name in filter_list:
+                filt = base.get_filter(name)
+                transmission[name] = filt.trans_table
+                effective_wavelength[name] = filt.effective_wavelength
 
         # We get the redshift module.
         redshift_module = get_module(redshift_module_name,

pcigale/analysis_modules/savefluxes.py

@@ -97,9 +97,8 @@ class SaveFluxes(AnalysisModule):
         # Get the filters in the database
         filter_names = [name for name in column_list
                         if not name.endswith('_err')]
-        base = Database()
-        filter_list = [base.get_filter(name) for name in filter_names]
-        base.close()
+        with Database() as base:
+            filter_list = [base.get_filter(name) for name in filter_names]
 
         # Columns of the output table
         out_columns = []

pcigale/creation_modules/bc03.py

@@ -66,9 +66,8 @@ class BC03(CreationModule):
         """Read the SSP from the database."""
         imf = self.parameters["imf"]
         metallicity = float(self.parameters["metallicity"])
-        database = Database()
-        self.ssp = database.get_ssp_bc03(imf, metallicity)
-        database.session.close_all()
+        with Database() as database:
+            self.ssp = database.get_ssp_bc03(imf, metallicity)
 
     def process(self, sed):
         """Add the convolution of a Bruzual and Charlot SSP to the SED

pcigale/creation_modules/dale2014.py

@@ -66,10 +66,9 @@ class Dale2014(CreationModule):
         """
         alpha = self.parameters["alpha"]
 
-        database = Database()
-        self.model_sb = database.get_dale2014(0.00, alpha)
-        self.model_quasar = database.get_dale2014(1.00, alpha)
-        database.session.close_all()
+        with Database() as database:
+            self.model_sb = database.get_dale2014(0.00, alpha)
+            self.model_quasar = database.get_dale2014(1.00, alpha)
 
     def process(self, sed):
         """Add the IR re-emission contributions

pcigale/creation_modules/dh2002.py

@@ -48,9 +48,8 @@ class DH2002(CreationModule):
 
     def _init_code(self):
         """Get the template set out of the database"""
-        database = Database()
-        self.dh2002 = database.get_dh2002_infrared_templates()
-        database.session.close_all()
+        with Database() as database:
+            self.dh2002 = database.get_dh2002_infrared_templates()
 
     def process(self, sed):
         """Add the IR re-emission contributions

pcigale/creation_modules/dl2007.py

@@ -76,10 +76,9 @@ class DL2007(CreationModule):
         umax = self.parameters["umax"]
         gamma = self.parameters["gamma"]
 
-        database = Database()
-        self.model_minmin = database.get_dl2007(qpah, umin, umin)
-        self.model_minmax = database.get_dl2007(qpah, umin, umax)
-        database.session.close_all()
+        with Database() as database:
+            self.model_minmin = database.get_dl2007(qpah, umin, umin)
+            self.model_minmax = database.get_dl2007(qpah, umin, umax)
 
         # The models in memory are in W/nm for 1 kg of dust. At the same time
         # we need to normalize them to 1 W here to easily scale them from the

pcigale/creation_modules/dustatt_calzleit.py

@@ -258,10 +258,9 @@ class CalzLeit(CreationModule):
         filter_list = [item.strip() for item in
                        self.parameters["filters"].split("&")]
         self.filters = {}
-        base = Database()
-        for filter_name in filter_list:
-            self.filters[filter_name] = base.get_filter(filter_name)
-        base.close()
+        with Database() as base:
+            for filter_name in filter_list:
+                self.filters[filter_name] = base.get_filter(filter_name)
 
     def process(self, sed):
         """Add the CCM dust attenuation to the SED.

pcigale/creation_modules/dustatt_powerlaw.py

@@ -182,10 +182,9 @@ class PowerLawAtt(CreationModule):
         filter_list = [item.strip() for item in
                        self.parameters["filters"].split("&")]
         self.filters = {}
-        base = Database()
-        for filter_name in filter_list:
-            self.filters[filter_name] = base.get_filter(filter_name)
-        base.close()
+        with Database() as base:
+            for filter_name in filter_list:
+                self.filters[filter_name] = base.get_filter(filter_name)
 
     def process(self, sed):
         """Add the CCM dust attenuation to the SED.

pcigale/creation_modules/m2005.py

@@ -104,9 +104,8 @@ class M2005(CreationModule):
         """Read the SSP from the database."""
         imf = self.parameters["imf"]
         metallicity = float(self.parameters["metallicity"])
-        database = Database()
-        self.ssp = database.get_ssp_m2005(imf, metallicity)
-        database.session.close_all()
+        with Database() as database:
+            self.ssp = database.get_ssp_m2005(imf, metallicity)
 
     def process(self, sed):
         """Add the convolution of a Maraston 2005 SSP to the SED

pcigale/data/__init__.py

@@ -217,6 +217,12 @@ class Database(object):
         self.session = SESSION()
         self.is_writable = writable
 
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.close()
+
     def upgrade_base(self):
         """ Upgrade the table schemas in the database
         """

pcigale/session/configuration.py

@@ -150,9 +150,8 @@ class Configuration(object):
         """
 
         # Getting the list of the filters available in pcigale database
-        base = Database()
-        filter_list = base.get_filter_list()[0]
-        base.close()
+        with Database() as base:
+            filter_list = base.get_filter_list()[0]
 
         # Finding the known filters in the data table
         obs_table = atpy.Table(self.config['data_file'], verbose=False)