Support KissCache style proxies

LAVA supports an alternative cache style where it just passes the URL to
be fetched to a web service and accepts whatever the web service
provides as valid, allowing caching of objects served over HTTPS without
complicated certificate management.  This is configured in the worker
config with the 'http_url_format_string' parameter, support doing so via
lava-docker.

Signed-off-by: Mark Brown <[email protected]>

README.md

@@ -479,7 +479,9 @@ There are two way to add custom devices types.
 	If you are modifying an already present (upstream) device-type, it is the best way.
 
 ## How to made LAVA slave use a proxy ?
-Add env to a slave like:
+
+For a standard HTTP/HTTPS proxy add env to a slave like:
+
 slave:
   env:
   - "http_proxy: http://dns:port"
@@ -490,6 +492,11 @@ Or on master via
        - "http_proxy: http://squid_IP_address:3128"
        - "https_proxy: http://squid_IP_address:3128"
 
+Or alternatively for a URL format string style proxy such as KissCache:
+
+slave:
+  http_url_format_string: http://kisscache_host:port
+
 
 ## How to use a board which uses PXE ?
 All boards which uses PXE, could be used with LAVA via grub.

lavalab-gen.py

@@ -420,7 +420,7 @@ def main():
             "custom_volumes",
             "devices", "dispatcher_ip", "default_slave",
             "extra_actions", "export_ser2net", "expose_ser2net", "expose_ports", "env",
-            "host", "host_healthcheck",
+            "host", "host_healthcheck", "http_url_format_string",
             "loglevel", "lava-coordinator", "lava_worker_token",
             "name",
             "remote_user", "remote_master", "remote_address", "remote_rpc_port", "remote_proto", "remote_user_token",
@@ -564,7 +564,7 @@ def main():
             fcoordinator.close()
         if "dispatcher_ip" in worker:
             fconfig = open("%s/worker-config" % workerdir, 'a')
-            fconfig.write("dispatcher_ip: %s" % worker["dispatcher_ip"])
+            fconfig.write("dispatcher_ip: %s\n" % worker["dispatcher_ip"])
             fconfig.close()
         if "expose_ports" in worker:
             for eports in worker["expose_ports"]:
@@ -583,6 +583,10 @@ def main():
             if remote_master in worker and "build_args" in worker[remote_master]:
                 dockcomp["services"]["healthcheck"]["build"]["args"] = worker[remote_master]['build_args']
             shutil.copytree("healthcheck", "output/%s/healthcheck" % host)
+        if "http_url_format_string" in worker:
+            fconfig = open("%s/worker-config" % workerdir, 'a')
+            fconfig.write("http_url_format_string: \"%s\"\n" % worker["http_url_format_string"])
+            fconfig.close()
         if "extra_actions" in worker:
             fp = open("%s/scripts/extra_actions" % workerdir, "w")
             for eaction in worker["extra_actions"]: