task callsites: part 2 (#4188)

* add struct logging to docs serve

* remove merge fluff

* struct logging to seed command

* converting print to use structured logging

* more structured logging print conversion

* pulling apart formatting more

* added struct logging by disecting printer.py

* add struct logging to runnable

* add struct logging to task init

* fixed formatting

* more formatting and moving things around

core/dbt/events/format.py

@@ -0,0 +1,35 @@
+import dbt.logger as logger  # type: ignore # TODO eventually remove dependency on this logger
+from dbt import ui
+from typing import Optional
+
+
+def format_fancy_output_line(
+        msg: str, status: str, index: Optional[int],
+        total: Optional[int], execution_time: Optional[float] = None,
+        truncate: bool = False
+) -> str:
+    if index is None or total is None:
+        progress = ''
+    else:
+        progress = '{} of {} '.format(index, total)
+    # TODO: remove this formatting once we rip out all the old logger
+    prefix = "{timestamp} | {progress}{message}".format(
+        timestamp=logger.get_timestamp(),
+        progress=progress,
+        message=msg)
+
+    truncate_width = ui.printer_width() - 3
+    justified = prefix.ljust(ui.printer_width(), ".")
+    if truncate and len(justified) > truncate_width:
+        justified = justified[:truncate_width] + '...'
+
+    if execution_time is None:
+        status_time = ""
+    else:
+        status_time = " in {execution_time:0.2f}s".format(
+            execution_time=execution_time)
+
+    output = "{justified} [{status}{status_time}]".format(
+        justified=justified, status=status, status_time=status_time)
+
+    return output