Update ROADMAP and constraints

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>
This commit is contained in:
Alex Ellis (OpenFaaS Ltd)
2021-01-13 14:35:15 +00:00
parent 954a61cee1
commit a4a33b8596
2 changed files with 79 additions and 52 deletions

View File

@ -1,5 +1,76 @@
# faasd backlog and features
## Supported operations
* `faas login`
* `faas up`
* `faas list`
* `faas describe`
* `faas deploy --update=true --replace=false`
* `faas invoke --async`
* `faas invoke`
* `faas rm`
* `faas store list/deploy/inspect`
* `faas version`
* `faas namespace`
* `faas secret`
* `faas logs`
* `faas auth` - supported for Basic Authentication and OpenFaaS PRO with OIDC and Single-sign On.
Scale from and to zero is also supported. On a Dell XPS with a small, pre-pulled image unpausing an existing task took 0.19s and starting a task for a killed function took 0.39s. There may be further optimizations to be gained.
## Constraints vs OpenFaaS on Kubernetes
faasd suits certain use-cases as mentioned in the README file, for those who want a solution which can scale out horizontally with minimum effort, Kubernetes or K3s is a valid option.
### One replica per function
Functions only support one replica, so cannot scale horizontally, but can scale vertically.
Workaround: deploy one uniquely named function per replica.
### Scale from zero may give a non-200
When scaling from zero there is no health check implemented, so the request may arrive before your HTTP server is ready to serve a request, and therefore give a non-200 code.
Workaround: Do not scale to zero, or have your client retry HTTP calls.
### No clustering is available
No clustering is available in faasd, however you can still apply fault-tolerance and high availability techniques.
Workaround: deploy multiple faasd instances and use a hardware or software load-balancer. Take regular VM/host snapshots or backups.
### No rolling updates
When running `faas-cli deploy`, your old function is removed before the new one is started. This may cause a small amount of downtime, depending on the timeouts and grace periods you set.
Workaround: deploy uniquely named functions per version, and switch an Ingress or Reverse Proxy record to point at a new version once it is ready.
## Known issues
### Non 200 HTTP status from the gateway upon first use
This issue appears to happen sporadically and only for some users.
If you get a non 200 HTTP code from the gateway, or caddy after installing faasd, check the logs of faasd:
```bash
sudo journalctl -t faasd
```
If you see the following error:
```
unable to dial to 10.62.0.5:8080, error: dial tcp 10.62.0.5:8080: connect: no route to host
```
Restart the faasd service with:
```bash
sudo systemctl restart faasd
```
## Backlog
Should have:
@ -42,3 +113,4 @@ Nice to Have:
* [x] Terraform for DigitalOcean
* [x] [Store and retrieve annotations in function spec](https://github.com/openfaas/faasd/pull/86) - in progress
* [x] An installer for faasd and dependencies - runc, containerd