From 797bf9830c6bc40ef74df30baedfdea0658826a6 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sb@m-labs.hk>
Date: Sat, 17 Oct 2015 10:39:21 +0800
Subject: [PATCH] language: add basic logging initializer for experiments

---
 artiq/language/__init__.py                   |  4 +++-
 artiq/language/logging.py                    | 23 ++++++++++++++++++++
 examples/master/repository/arguments_demo.py | 15 ++++++-------
 3 files changed, 33 insertions(+), 9 deletions(-)
 create mode 100644 artiq/language/logging.py

diff --git a/artiq/language/__init__.py b/artiq/language/__init__.py
index 39edc6164..c7be4eb9b 100644
--- a/artiq/language/__init__.py
+++ b/artiq/language/__init__.py
@@ -1,10 +1,11 @@
 # Copyright (C) 2014, 2015 Robert Jordens <jordens@gmail.com>
 
-from artiq.language import core, environment, units, scan
+from artiq.language import core, environment, units, scan, logging
 from artiq.language.core import *
 from artiq.language.environment import *
 from artiq.language.units import *
 from artiq.language.scan import *
+from artiq.language.logging import *
 
 
 __all__ = []
@@ -12,3 +13,4 @@ __all__.extend(core.__all__)
 __all__.extend(environment.__all__)
 __all__.extend(units.__all__)
 __all__.extend(scan.__all__)
+__all__.extend(logging.__all__)
diff --git a/artiq/language/logging.py b/artiq/language/logging.py
new file mode 100644
index 000000000..c64a3dbf6
--- /dev/null
+++ b/artiq/language/logging.py
@@ -0,0 +1,23 @@
+from artiq.language.environment import *
+
+import logging
+
+
+__all__ = ["LogExperiment"]
+
+
+class LogExperiment:
+    def init_logger(self):
+        """Call this from build() to add a logging level enumeration
+        widget, initialize logging globally, and create a logger.
+
+        Your class must also derive from ``HasEnvironment`` (or
+        ``EnvExperiment``).
+
+        The created logger is called ``self.logger``."""
+        level = self.get_argument("log_level", EnumerationValue(
+            ["DEBUG", "INFO", "WARNING", "ERROR", "CRITICAL"]))
+
+        if level is not None:
+            logging.basicConfig(level=getattr(logging, level))
+            self.logger = logging.getLogger(self.__class__.__name__)
diff --git a/examples/master/repository/arguments_demo.py b/examples/master/repository/arguments_demo.py
index ffb6e2ac2..a0114c211 100644
--- a/examples/master/repository/arguments_demo.py
+++ b/examples/master/repository/arguments_demo.py
@@ -1,5 +1,3 @@
-import logging
-
 from artiq import *
 
 
@@ -35,8 +33,10 @@ class SubComponent2(HasEnvironment):
         print(self.sc2_enum)
 
 
-class ArgumentsDemo(EnvExperiment):
+class ArgumentsDemo(EnvExperiment, LogExperiment):
     def build(self):
+        self.init_logger()
+
         self.setattr_argument("free_value", FreeValue(None))
         self.setattr_argument("number", NumberValue(42e-6,
                                                     unit="s", scale=1e-6,
@@ -53,11 +53,10 @@ class ArgumentsDemo(EnvExperiment):
         self.sc2 = SubComponent2(parent=self)
 
     def run(self):
-        logging.basicConfig(level=logging.DEBUG)
-        logging.error("logging test: error")
-        logging.warning("logging test: warning")
-        logging.info("logging test: info")
-        logging.debug("logging test: debug")
+        self.logger.error("logging test: error")
+        self.logger.warning("logging test: warning")
+        self.logger.info("logging test: info")
+        self.logger.debug("logging test: debug")
 
         print(self.free_value)
         print(self.boolean)