support/testing: add haproxy test

Based on the lighttpd test case.  Verify that we can download index.html
from haproxy in front of lighttpd.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

support/testing/conf/haproxy.cfg

@@ -0,0 +1,13 @@
+defaults
+    timeout connect 10s
+    timeout client 30s
+    timeout server 30s
+
+frontend myfrontend
+  mode http
+  bind :81
+  default_backend web_servers
+
+backend web_servers
+  mode http
+  server s1 localhost:80 check

support/testing/tests/package/test_haproxy.py

@@ -0,0 +1,38 @@
+import os
+
+import infra.basetest
+
+
+class TestHaproxy(infra.basetest.BRTest):
+    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
+        """
+        BR2_ROOTFS_POST_BUILD_SCRIPT="{}"
+        BR2_ROOTFS_POST_SCRIPT_ARGS="{}"
+        BR2_PACKAGE_HAPROXY=y
+        BR2_PACKAGE_LIGHTTPD=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """.format(
+            infra.filepath("tests/package/copy-sample-script-to-target.sh"),
+            infra.filepath("conf/haproxy.cfg")
+        )
+
+    def test_run(self):
+        cpio_file = os.path.join(self.builddir, "images", "rootfs.cpio")
+        self.emulator.boot(arch="armv5",
+                           kernel="builtin",
+                           options=["-initrd", cpio_file])
+        self.emulator.login()
+
+        msg = "Hello Buildroot!"
+
+        # sanity check
+        self.assertRunOk("haproxy -v")
+        self.assertRunOk("haproxy -c -f .")
+
+        # proxy to lighttpd
+        self.assertRunOk("haproxy -D -f .")
+
+        self.assertRunOk(f"echo '{msg}' > /var/www/index.html")
+        self.assertRunOk("wget http://localhost:81/index.html")
+        self.assertRunOk(f"grep -F '{msg}' index.html")