From 6000883f8d3ecc249066cc2fb7a7f1ec93580b9f Mon Sep 17 00:00:00 2001
From: Tom Krizek <tkrizek@isc.org>
Date: Thu, 12 Jan 2023 16:41:41 +0100
Subject: [PATCH] Obtain env vars from conf.sh in pytest runner

The commands executed by pytest during a system test need to have the
same environment variables set as if they were executed by the run.sh
shell script.

It was decided that for the moment, legacy way of executing system tests
with run.sh should be kept, which complicates things a bit. In order to
avoid duplicating the required variables in both conf.sh and pytest, it
was decided to use the existing conf.sh as the only authoritative
place for the variables.

It is necessary to process the environment variables from conf.sh right
when conftest.py is loaded, since they might be needed right away (e.g.
to test for feature support during test collection).

This solution is a bit hacky and is only meant to be used during the
transitory phase when both pytest and the legacy run.sh are both
supported. In the future, a superior pytest-only solution should be
used.

For discussion of other options, refer to
https://gitlab.isc.org/isc-projects/bind9/-/merge_requests/6809#note_318889

(cherry picked from commit 2f7af791a1291f06887437623bd224a3447cec50)
---
 bin/tests/system/conftest.py | 42 +++++++++++++++++++++++++++++++++++-
 1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/bin/tests/system/conftest.py b/bin/tests/system/conftest.py
index 009d989ceb..f77a1b1097 100644
--- a/bin/tests/system/conftest.py
+++ b/bin/tests/system/conftest.py
@@ -49,4 +49,44 @@ def control_port():
 # don't branch the code.
 
 if os.getenv("LEGACY_TEST_RUNNER", "0") == "0":
-    pass  # will be implemented in followup commits
+    import logging
+    from pathlib import Path
+    import re
+    import subprocess
+
+    # ----------------------- Globals definition -----------------------------
+
+    FILE_DIR = os.path.abspath(Path(__file__).parent)
+    ENV_RE = re.compile("([^=]+)=(.*)")
+
+    # ---------------------- Module initialization ---------------------------
+
+    def parse_env(env_text):
+        """Parse the POSIX env format into Python dictionary."""
+        out = {}
+        for line in env_text.splitlines():
+            match = ENV_RE.match(line)
+            if match:
+                out[match.groups()[0]] = match.groups()[1]
+        return out
+
+    def get_env(cmd):
+        try:
+            proc = subprocess.run(
+                [cmd],
+                shell=True,
+                check=True,
+                cwd=FILE_DIR,
+                stdout=subprocess.PIPE,
+            )
+        except subprocess.CalledProcessError as exc:
+            logging.error("failed to get shell env: %s", exc)
+            raise exc
+        env_text = proc.stdout.decode("utf-8")
+        return parse_env(env_text)
+
+    # Read common environment variables for running tests from conf.sh.
+    # FUTURE: Remove conf.sh entirely and define all variables in pytest only.
+    CONF_ENV = get_env(". ./conf.sh && env")
+    os.environ.update(CONF_ENV)
+    logging.debug("conf.sh env: %s", CONF_ENV)