Remove revision from Alpine Linux

This causes noise from dependabot, where it tries to bunch each
patch revision in a separate PR.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Upgrade to faas-provider 0.17.1

**What**
- Update faas-provider to get the proxy implementation that allows CORS
  requests (OPTIONS) and HEAD.

Signed-off-by: Lucas Roesler <roesler.lucas@gmail.com>

Update provider to v0.17.0

When endpoints are not found, a 503 instead of 404 is returned
from faas-netes.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Log and run each informer explicitly

Since adding a wait for the cache to sync for Kubernetes endpoints,
there appears to be conditions where the code waits indefinitely.

The issue can be reproduced by scaling the gateway to zero replicas
and back to 1, some of the time it passes the sync, other times
it gets stuck.

This patch appears to fix the problem and has been tested in
controller and operator mode on an RPi 4x node cluster and
with k3d with hey running a load test into the nodeinfo function
with a minimum of 10 replicas.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Set allowPrivilegeEscalation to false as a default

This commit fixes openfaas#523 and sets a default, which nobody has
raised any concerns with. If this affects you in a negative
way then please feel free to raise an issue for discussion.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Sync endpoints before starting HTTP server

The HTTP server which is used for CRUD and invocations should
not be started until the cached informers for endpoints is
ready. This may be related to issue openfaas#749

The cache sync duration is now being logged and measured for
users to provide logs and additional information.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

update info endpoint to use ProviderInfo struct

This commit updates faas-netes provider to updated ProviderInfo struct to return provider
version information to gateway.

Signed-off-by: Vivek Singh <vivekkmr45@yahoo.in>

Enable Go durations for timeouts

This affects the operator, which was failing to parse
the durations being passed to it as Go durations. It supported
ints, but wasn't required since this is code already exists
and is used for the controller.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Fix issue with filtering deployments

Fixes issue: openfaas#736 raised by pkoelbl where all deployments in
the openfaas-fn namespace were being returned via the REST
API when listing functions.

The selector's Add method was generating a new value to be
returned instead of updating itself. A negative test would have
shown this and may be worth adding to the codebase at a
later date, or being mocked/stubbed. A PR would be welcomed
for this.

Thanks also to @LucasRoesler for helping to investigate
and confirm the fix.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Handle null env vars

There was an error related to the following issue in
openfaas-cloud, which will also occur in faas-cli, where
null env-vars were serialized and passed into the spec.

This change has been tested and fixes the problem.

openfaas/openfaas-cloud#707

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>