Exception messages are useful, but what would make it even more useful is progress messages. Something that can tell us more about the why of an exception.
Progress messages are made using the standard Python logging mechanism.
Here is what we will be developing in this example.
1 CollectCaptainAmerica -> None0 ValidateCaptainAmerica -> Captain America+-- INFO: Entering validator..+-- INFO: About to validate instance: "Captain America"+-- WARNING: Something is not right, aborting..+-- EXCEPTION: Captain America must be a hero
For this, we will utilise the built-in logger.
class ValidateCaptainAmerica(pyblish.api.InstancePlugin):order = pyblish.api.ValidatorOrderdef process(self, instance):self.log.info("Entering validator..")self.log.info("About to validate instance: %s" % instance)if not instance.data["isHero"]:self.log.warning("Something is not right.. aborting")raise Exception("%s must be a hero" % instance)
Now it's time to format the results.
header = "{:<10}{:<40} -> {}".format("Success", "Plug-in", "Instance")result = "{success:<10}{plugin.__name__:<40} -> {instance}"error = "{:<10}+-- EXCEPTION: {:<70}"record = "{:<10}+-- {level}: {message:<70}"results = list()for r in context.data["results"]:# Format summaryresults.append(result.format(**r))# Format log recordsfor lr in r["records"]:results.append(record.format("", level=lr.levelname, message=lr.msg))# Format exception (if any)if r["error"]:results.append(error.format("", r["error"]))report = """{header}{line}{results}"""print(report.format(header=header,results="\n".join(results),line="-" * 70))
Putting it all together, here is the full source code.
import pyblish.apiclass CollectCaptainAmerica(pyblish.api.ContextPlugin):order = pyblish.api.CollectorOrderdef process(self, context):context.create_instance("Captain America", isHero=False)class ValidateCaptainAmerica(pyblish.api.InstancePlugin):order = pyblish.api.ValidatorOrderdef process(self, instance):self.log.info("Entering validator..")self.log.info("About to validate instance: %s" % instance)if not instance.data.get("isHero"):self.log.warning("Something is not right.. aborting")raise Exception("%s must be a hero" % instance)pyblish.api.register_plugin(CollectCaptainAmerica)pyblish.api.register_plugin(ValidateCaptainAmerica)import pyblish.utilcontext = pyblish.util.publish()header = "{:<10}{:<40} -> {}".format("Success", "Plug-in", "Instance")result = "{success:<10}{plugin.__name__:<40} -> {instance}"error = "{:<10}+-- EXCEPTION: {:<70}"record = "{:<10}+-- {level}: {message:<70}"results = list()for r in context.data["results"]:# Format summaryresults.append(result.format(**r))# Format log recordsfor lr in r["records"]:results.append(record.format("", level=lr.levelname, message=lr.msg))# Format exception (if any)if r["error"]:results.append(error.format("", r["error"]))report = """{header}{line}{results}"""print(report.format(header=header,results="\n".join(results),line="-" * 70))