Added coloredlogs

Pimlico now always tries to install and load coloredlogs, so that the
extensive logging output it produces is a bit easier to read.

If it fails, it doesn't worry about it.

src/python/pimlico/__init__.py

@@ -33,7 +33,7 @@
     reload(site)
 
 from pimlico.core.dependencies.base import check_and_install
-from pimlico.core.dependencies.core import CORE_PIMLICO_DEPENDENCIES
+from pimlico.core.dependencies.core import CORE_PIMLICO_DEPENDENCIES, coloredlogs_dependency
 
 PIMLICO_ROOT = os.path.abspath(os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "..", ".."))
 
@@ -74,6 +74,18 @@ def install_core_dependencies():
             print("Unable to install all core dependencies: exiting", file=sys.stderr)
             sys.exit(1)
 
+    # Special procedure for coloredlogs
+    # This is nice to have, but if we can't install it or load it, it's not a problem
+    try:
+        if not coloredlogs_dependency.available({}):
+            print("Installing coloredlogs")
+            coloredlogs_dependency.install({})
+        # Load coloredlogs and start using it for all logging formatters
+        import coloredlogs
+        coloredlogs.install()
+    except Exception as e:
+        print("Error installing and loading colorlogs. Logs will not be coloured. {}".format(e))
+
 
 def get_jupyter_pipeline():
     """

src/python/pimlico/core/dependencies/core.py

@@ -5,7 +5,7 @@
 
 from future.utils import PY2
 
-from pimlico.core.dependencies.python import PythonPackageOnPip, PythonPackageSystemwideInstall
+from pimlico.core.dependencies.python import PythonPackageOnPip
 
 #: Core dependencies required by the basic Pimlico installation, regardless of what pipeline is being processed.
 #: These will be checked when Pimlico is run, using the same dependency-checking mechanism that Pimlico modules
@@ -34,3 +34,6 @@
         # Provides a backport of Py3's updated and renamed configparser package
         PythonPackageOnPip("configparser"),
     ])
+
+
+coloredlogs_dependency = PythonPackageOnPip("coloredlogs")

src/python/pimlico/test/suite.py

@@ -4,6 +4,11 @@
 from pimlico.test.pipeline import run_test_suite
 from pimlico.utils.logging import get_console_logger
 
+if __name__ == "__main__":
+    from pimlico import install_core_dependencies
+    install_core_dependencies()
+
+
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description="Pipeline test suite runner")
     parser.add_argument("suite_file", help="CSV file in which each line contains a path to a pipeline config file "