travis-ci: build and test Git on Windows

Most Git developers work on Linux and they have no way to know if their
changes would break the Git for Windows build. Let's fix that by adding
a job to TravisCI that builds and tests Git on Windows. Unfortunately,
TravisCI does not support Windows.

Therefore, we did the following:
* Johannes Schindelin set up a Visual Studio Team Services build
sponsored by Microsoft and made it accessible via an Azure Function
that speaks a super-simple API. We made TravisCI use this API to
trigger a build, wait until its completion, and print the build and
test results.
* A Windows build and test run takes up to 3h and TravisCI has a timeout
after 50min for Open Source projects. Since the TravisCI job does not
use heavy CPU/memory/etc. resources, the friendly TravisCI folks
extended the job timeout for git/git to 3h.

Things, that would need to be done:
* Someone with write access to https://travis-ci.org/git/git would need
to add the secret token as "GFW_CI_TOKEN" variable in the TravisCI
repository setting [1]. Afterwards the build should just work.

Things, that might need to be done:
* The Windows box can only process a single build at a time. A second
Windows build would need to wait until the first finishes. This
waiting time and the build time after the wait could exceed the 3h
threshold. If this is a problem, then it is likely to happen every day
as usually multiple branches are pushed at the same time (pu/next/
master/maint). I cannot test this as my TravisCI account has the 50min
timeout. One solution could be to limit the number of concurrent
TravisCI jobs [2].

[1] https://docs.travis-ci.com/user/environment-variables#Defining-Variables-in-Repository-Settings
[2] https://docs.travis-ci.com/user/customizing-the-build#Limiting-Concurrent-Builds

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/.travis.yml b/.travis.yml
index 591cc57b80aa415be9c20b3c0dc746d792e68071..c757a111ce3ec59f503274fd13d9191c0c70a0fa 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -39,6 +39,17 @@ env:
 
 matrix:
   include:
+    - env: Windows
+      os: linux
+      compiler:
+      addons:
+      before_install:
+      before_script:
+      script:
+        - >
+          test "$TRAVIS_REPO_SLUG" != "git/git" ||
+          ci/run-windows-build.sh $TRAVIS_BRANCH $(git rev-parse HEAD)
+      after_failure:
     - env: Linux32
       os: linux
       services:

diff --git a/ci/run-windows-build.sh b/ci/run-windows-build.sh
new file mode 100755 (executable)
index 0000000..4e3a50b
--- /dev/null
+++ b/ci/run-windows-build.sh
@@ -0,0 +1,74 @@
+#!/usr/bin/env bash
+#
+# Script to trigger the a Git for Windows build and test run.
+# Set the $GFW_CI_TOKEN as environment variable.
+# Pass the branch (only branches on https://github.com/git/git are
+# supported) and a commit hash.
+#
+
+test $# -ne 2 && echo "Unexpected number of parameters" && exit 1
+test -z "$GFW_CI_TOKEN" && echo "GFW_CI_TOKEN not defined" && exit
+
+BRANCH=$1
+COMMIT=$2
+
+gfwci () {
+       local CURL_ERROR_CODE HTTP_CODE
+       exec 3>&1
+       HTTP_CODE=$(curl \
+               -H "Authentication: Bearer $GFW_CI_TOKEN" \
+               --silent --retry 5 --write-out '%{HTTP_CODE}' \
+               --output >(sed "$(printf '1s/^\xef\xbb\xbf//')" >cat >&3) \
+               "https://git-for-windows-ci.azurewebsites.net/api/TestNow?$1" \
+       )
+       CURL_ERROR_CODE=$?
+       if test $CURL_ERROR_CODE -ne 0
+       then
+               return $CURL_ERROR_CODE
+       fi
+       if test "$HTTP_CODE" -ge 400 && test "$HTTP_CODE" -lt 600
+       then
+               return 127
+       fi
+}
+
+# Trigger build job
+BUILD_ID=$(gfwci "action=trigger&branch=$BRANCH&commit=$COMMIT&skipTests=false")
+if test $? -ne 0
+then
+       echo "Unable to trigger Visual Studio Team Services Build"
+       echo "$BUILD_ID"
+       exit 1
+fi
+
+# Check if the $BUILD_ID contains a number
+case $BUILD_ID in
+''|*[!0-9]*) echo "Unexpected build number: $BUILD_ID" && exit 1
+esac
+
+echo "Visual Studio Team Services Build #${BUILD_ID}"
+
+# Wait until build job finished
+STATUS=
+RESULT=
+while true
+do
+       LAST_STATUS=$STATUS
+       STATUS=$(gfwci "action=status&buildId=$BUILD_ID")
+       test "$STATUS" = "$LAST_STATUS" || printf "\nStatus: $STATUS "
+       printf "."
+
+       case "$STATUS" in
+       inProgress|postponed|notStarted) sleep 10               ;; # continue
+                "completed: succeeded") RESULT="success"; break;; # success
+       *) echo "Unhandled status: $STATUS";               break;; # failure
+       esac
+done
+
+# Print log
+echo ""
+echo ""
+gfwci "action=log&buildId=$BUILD_ID" | cut -c 30-
+
+# Set exit code for TravisCI
+test "$RESULT" = "success"