add adapter logging interface

core/dbt/events/README.md

@@ -7,3 +7,16 @@ The event module provides types that represent what is happening in dbt in `even
 
 # Adding a New Event
 In `events.types` add a new class that represents the new event. This may be a simple class with no values, or it may be a dataclass with some values to construct downstream messaging. Only include the data necessary to construct this message within this class. You must extend all destinations (e.g. - if your log message belongs on the cli, extend `CliEventABC`) as well as the loglevel this event belongs to.
+
+# Adapter Maintainers
+To integrate existing log messages from adapters, you likely have a line of code like this in your adapter already:
+```python
+from dbt.logger import GLOBAL_LOGGER as logger
+```
+
+Simply change it to these two lines with your adapter's database name, and all your existing call sites will now use the new system for v1.0:
+```python
+from dbt.events import AdapterLogger
+logger = AdapterLogger("<database name>")
+# e.g. AdapterLogger("Snowflake")
+```

core/dbt/events/__init__.py

@@ -0,0 +1 @@
+from .adapter_endpoint import AdapterLogger  # noqa: F401

core/dbt/events/adapter_endpoint.py

@@ -0,0 +1,22 @@
+from dataclasses import dataclass
+from dbt.events.functions import fire_event
+from dbt.events.types import (
+    AdapterEventDebug, AdapterEventInfo, AdapterEventWarning, AdapterEventError
+)
+
+
+@dataclass
+class AdapterLogger():
+    name: str
+
+    def debug(self, msg: str):
+        fire_event(AdapterEventDebug(name=self.name, raw_msg=msg))
+
+    def info(self, msg: str):
+        fire_event(AdapterEventInfo(name=self.name, raw_msg=msg))
+
+    def warning(self, msg: str):
+        fire_event(AdapterEventWarning(name=self.name, raw_msg=msg))
+
+    def error(self, msg: str):
+        fire_event(AdapterEventError(name=self.name, raw_msg=msg))

core/dbt/events/types.py

@@ -63,6 +63,31 @@ def cli_msg(self) -> str:
         raise Exception("cli_msg not implemented for cli event")
 
 
+@dataclass
+class AdapterEventBase():
+    name: str
+    raw_msg: str
+
+    def cli_msg(self) -> str:
+        return f"{self.name} adapter: {self.raw_msg}"
+
+
+class AdapterEventDebug(DebugLevel, AdapterEventBase, CliEventABC):
+    pass
+
+
+class AdapterEventInfo(InfoLevel, AdapterEventBase, CliEventABC):
+    pass
+
+
+class AdapterEventWarning(WarnLevel, AdapterEventBase, CliEventABC):
+    pass
+
+
+class AdapterEventError(ErrorLevel, AdapterEventBase, CliEventABC):
+    pass
+
+
 class ParsingStart(InfoLevel, CliEventABC):
     def cli_msg(self) -> str:
         return "Start parsing."