From a1b346a677e85153caea447737fe8f60bf05ccb2 Mon Sep 17 00:00:00 2001
From: Guillaume Tucker <guillaume.tucker@collabora.com>
Date: Fri, 19 Aug 2022 21:24:30 +0200
Subject: [PATCH] staging.kernelci.org: only restart API if there were changes

Create a temporary local integration branch to look for a diff with
the current staging branch, then only restart the API if there are
changes.

That way, the API services don't need to be restarted at every staging
job and client scripts running elsewhere can remain connected.  They
will need to reopen their connections if the API is restarted, but
that's typically because of API changes so client-side changes are
most likely required too anyway.

Signed-off-by: Guillaume Tucker <guillaume.tucker@collabora.com>
---
 staging.kernelci.org | 40 ++++++++++++++++++++++++++--------------
 1 file changed, 26 insertions(+), 14 deletions(-)

diff --git a/staging.kernelci.org b/staging.kernelci.org
index b7207d8..297be57 100755
--- a/staging.kernelci.org
+++ b/staging.kernelci.org
@@ -244,29 +244,41 @@ cmd_rotate_tree() {
 }
 
 cmd_api_pipeline() {
-    echo "Stopping containers"
+    echo "Stopping pipeline containers"
     cd checkout/kernelci-pipeline
     docker-compose down
     cd -
-    cd checkout/kernelci-api
-    docker-compose down
-    cd -
 
-    echo "Updating API branch"
-    ./pending.py kernelci-api --push
+    echo "Creating local staging branch in tmp directory while API is running"
+    mkdir -p tmp
+    pending_api="../pending.py --settings=../data/staging.ini kernelci-api"
+    (cd tmp; $pending_api)
+
+    echo "Looking for diff with current staging branch"
+    if (cd tmp; $pending_api --diff-only); then
+        echo "Stopping API containers"
+        cd checkout/kernelci-api
+        docker-compose down
+        cd -
+
+        echo "Updating API branch"
+        ./pending.py kernelci-api --push
+
+        echo "Starting API containers"
+        cd checkout/kernelci-api
+        REQUIREMENTS=requirements-dev.txt docker-compose build
+        docker-compose up -d
+        cd -
+    else
+        echo "No API changes, leaving it running"
+    fi
 
     echo "Updating pipeline branch"
     ./pending.py kernelci-pipeline --push
 
-    echo "Restarting containers"
-    cd checkout/kernelci-api
-    REQUIREMENTS=requirements-dev.txt \
-        docker-compose build
-    docker-compose up -d
-    cd -
+    echo "Starting pipeline containers"
     cd checkout/kernelci-pipeline
-    REQUIREMENTS=requirements-dev.txt \
-        docker-compose build
+    REQUIREMENTS=requirements-dev.txt docker-compose build
     SETTINGS=/home/kernelci/config/staging.kernelci.org.conf \
         docker-compose up -d
     cd -