Add support for builtin profiles (WIP)

TODO:
- complement the "minimal.conf" profile
- add more builtin profiles (e.g. a "narrow.conf", to limit the number
  of columns)?
- add a compat layer around importlib.resources API
- add tests

CHANGELOG.md

@@ -9,6 +9,7 @@
   `${XDG_CONFIG_HOME:~/.config}/pg_activity/<profile>.conf` or
   `/etc/pg_activity/<profile>.conf` as selected from the command line through
   `--profile <profile>`.
+  A few built-in profiles are distributed with pg\_activity.
 
 ### Changed
 

README.md

@@ -164,6 +164,10 @@ files located at `${XDG_CONFIG_HOME:~/.config}/pg_activity/<my-profile>.conf` or
 `--profile <my-profile>` command-line option. The format of these files is the
 same as the main configuration file.
 
+`pg_activity` ships with a few built-in profiles:
+
+- `minimal`, providing a minimal user interface with most non-essential
+  information hidden
 
 [INI format]: https://docs.python.org/3/library/configparser.html#supported-ini-file-structure
 

pgactivity/compat.py

@@ -1,6 +1,7 @@
+import importlib.resources
 import operator
 import sys
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 import attr
 import attr.validators
@@ -11,6 +12,22 @@
 else:
     from importlib.metadata import version
 
+if sys.version_info >= (3, 11):
+
+    def read_resource(pkgname: str, dirname: str, *args: str) -> Optional[str]:
+        resource = importlib.resources.files(pkgname).joinpath(dirname)
+        for arg in args:
+            resource = resource.joinpath(arg)
+        if resource.is_file():
+            return resource.read_text()
+        return None
+
+else:
+
+    def read_resource(pkgname: str, dirname: str, *args: str) -> Optional[str]:
+        raise NotImplementedError
+
+
 ATTR_VERSION = tuple(int(x) for x in version("attrs").split(".", 2)[:2])
 BLESSED_VERSION = tuple(int(x) for x in version("blessed").split(".", 2)[:2])
 

pgactivity/config.py

@@ -1,13 +1,14 @@
 import configparser
 import enum
+import io
 import os
 from pathlib import Path
 from typing import IO, Any, Dict, List, Optional, Type, TypeVar
 
 import attr
 from attr import validators
 
-from .compat import gt
+from .compat import gt, read_resource
 
 
 class ConfigurationError(Exception):
@@ -188,6 +189,19 @@ def from_config_section(cls: Type[_T], section: configparser.SectionProxy) -> _T
         return cls(**values)
 
 
+@attr.s(auto_attribs=True, frozen=True, slots=True)
+class BuiltinProfile:
+    name: str
+    content: IO[str]
+
+    @classmethod
+    def get(cls, name: str) -> Optional["BuiltinProfile"]:
+        content = read_resource("pgactivity", "profiles", f"{name}.conf")
+        if content is not None:
+            return BuiltinProfile(name, io.StringIO(content))
+        return None
+
+
 USER_CONFIG_HOME = Path(os.environ.get("XDG_CONFIG_HOME", Path.home() / ".config"))
 ETC = Path("/etc")
 
@@ -282,4 +296,9 @@ def lookup(
             if fpath.exists():
                 with fpath.open() as f:
                     return cls.parse(f, str(fpath))
+
+        builtin_profile = BuiltinProfile.get(profile)
+        if builtin_profile is not None:
+            return cls.parse(builtin_profile.content, builtin_profile.name)
+
         raise FileNotFoundError(f"profile {profile!r} not found")

pgactivity/profiles/minimal.conf

@@ -0,0 +1,2 @@
+[database]
+hidden = yes