Use :atc-postgres-version: role in documentation

.env

@@ -1,3 +1,4 @@
 ATS_VERSION=9.2.4
 GO_VERSION=1.23.1
+POSTGRES_VERSION=13.2
 TOMCAT_VERSION=9.0.91

docs/source/_ext/atc.py

@@ -128,6 +128,33 @@ def atc_go_version(
 	strong_node = nodes.strong(major_minor_version, major_minor_version)
 	return [strong_node], []
 
+def atc_postgres_version(
+	unused_typ: None,
+	unused_rawtext: None,
+	unused_text: None,
+	lineno: int,
+	unused_inliner: None,
+	unused_options: None=None,
+	unused_content: None=None
+) -> Tuple[List[nodes.Node], List[nodes.Node]]:
+	"""
+	A role that inserts the Postgres version used/required by this version of ATC.
+
+	Example:
+
+		:atc-postgres-version:_
+	"""
+	env_file = os.path.join(os.path.dirname(__file__), "../../../.env")
+	with open(file=env_file, encoding="utf-8") as env_file:
+		env_file_contents = env_file.read()
+
+	matches = re.search(pattern=r"^POSTGRES_VERSION=(\d+\.\d+)$", string=env_file_contents, flags=re.MULTILINE)
+	if matches is None:
+		raise ValueError(f"Postgres version found that could not be parsed: '{env_file_contents}' (from line {lineno})")
+	major_minor_version = matches.group(1)
+	strong_node = nodes.strong(major_minor_version, major_minor_version)
+	return [strong_node], []
+
 # -- Issue role --------------------------------------------------------------
 
 ISSUE_URI: Final = REPO_URI + "issues/%s"
@@ -330,6 +357,7 @@ def setup(app: Sphinx) -> Dict[str, Any]:
 	app.add_directive("impl-detail", ImplementationDetail)
 	app.add_directive("versionremoved", VersionRemoved)
 	app.add_role("atc-go-version", atc_go_version)
+	app.add_role("atc-postgres-version", atc_postgres_version)
 	app.add_role("issue", issue_role)
 	app.add_role("pr", pr_role)
 	app.add_role("pull-request", pr_role)

docs/source/admin/traffic_ops.rst

@@ -87,7 +87,7 @@ Guide
 
 		to-# psql -h pg -U postgres
 		Password for user postgres:
-		psql (13.2)
+		psql (13.16)
 		Type "help" for help.
 
 		postgres=#

docs/source/development/traffic_ops.rst

@@ -28,7 +28,10 @@ Software Requirements
 =====================
 Traffic Ops is only supported on CentOS 7+ systems (although many developers do use Mac OS with some success). Here are the requirements:
 
-- `PostgreSQL 13.2 <https://www.postgresql.org/download/>`_ - the machine where Traffic Ops is running must have the client tool set (e.g. :manpage:`psql(1)`), but the actual database can be run anywhere so long as it is accessible.
+- |install-postgres-link|_ - the machine where Traffic Ops is running must have the client tool set (e.g. :manpage:`psql(1)`), but the actual database can be run anywhere so long as it is accessible.
+
+.. |install-postgres-link| replace:: PostgreSQL :atc-postgres-version:`_`
+.. _install-postgres-link: https://www.postgresql.org/download/
 
 	.. note:: Prior to version 13.2, Traffic Ops used version 9.6. For upgrading an existing Mac OS Homebrew-based PostgreSQL instance, you can use `Homebrew <https://brew.sh/>`_ to easily upgrade from 9.6 to 13.2: