mirror of
https://github.com/openfaas/faas.git
synced 2025-06-09 00:36:46 +00:00
88eea5f62e
Introduces a single-flight call to a function's health endpoint to verify that it is registered with an Istio sidecar (Envoy) before letting the invocation through. Results are cached for 5 seconds, before a probe is required again. Tested without Istio, with probe_functions environment variable set to true, I saw a probe execute in the logs. Fixes: #1721 for Istio users. Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alex@openfaas.com>
117 lines
2.9 KiB
Go
117 lines
2.9 KiB
Go
// Copyright (c) OpenFaaS Author(s). All rights reserved.
|
|
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
|
|
|
|
package probing
|
|
|
|
import (
|
|
"fmt"
|
|
"log"
|
|
"net/http"
|
|
"time"
|
|
|
|
"github.com/openfaas/faas/gateway/pkg/middleware"
|
|
"github.com/openfaas/faas/gateway/scaling"
|
|
"github.com/openfaas/faas/gateway/types"
|
|
)
|
|
|
|
// NewFunctionProber create a new scaler with the specified
|
|
// ScalingConfig
|
|
func NewFunctionProber(functionQuery scaling.FunctionQuery, resolver middleware.BaseURLResolver) FunctionProber {
|
|
// if directFunctions {
|
|
return &FunctionHTTPProber{
|
|
Query: functionQuery,
|
|
Resolver: resolver,
|
|
}
|
|
}
|
|
|
|
// FunctionHTTPProber probes a function's health endpoint
|
|
type FunctionHTTPProber struct {
|
|
Query scaling.FunctionQuery
|
|
Resolver middleware.BaseURLResolver
|
|
DirectFunctions bool
|
|
}
|
|
|
|
type FunctionNonProber struct {
|
|
}
|
|
|
|
func (f *FunctionNonProber) Probe(functionName, namespace string) FunctionProbeResult {
|
|
return FunctionProbeResult{
|
|
Found: true,
|
|
Available: true,
|
|
}
|
|
}
|
|
|
|
type FunctionProber interface {
|
|
Probe(functionName, namespace string) FunctionProbeResult
|
|
}
|
|
|
|
// FunctionProbeResult holds the result of scaling from zero
|
|
type FunctionProbeResult struct {
|
|
Available bool
|
|
Error error
|
|
Found bool
|
|
Duration time.Duration
|
|
Updated time.Time
|
|
}
|
|
|
|
// Expired find out whether the cache item has expired with
|
|
// the given expiry duration from when it was stored.
|
|
func (res *FunctionProbeResult) Expired(expiry time.Duration) bool {
|
|
return time.Now().After(res.Updated.Add(expiry))
|
|
}
|
|
|
|
// Scale scales a function from zero replicas to 1 or the value set in
|
|
// the minimum replicas metadata
|
|
func (f *FunctionHTTPProber) Probe(functionName, namespace string) FunctionProbeResult {
|
|
start := time.Now()
|
|
|
|
cachedResponse, _ := f.Query.Get(functionName, namespace)
|
|
probePath := "/_/health"
|
|
|
|
if cachedResponse.Annotations != nil {
|
|
if v, ok := (*cachedResponse.Annotations)["com.openfaas.http.path"]; ok && len(v) > 0 {
|
|
probePath = v
|
|
}
|
|
}
|
|
|
|
maxCount := 10
|
|
pollInterval := time.Millisecond * 50
|
|
|
|
err := types.Retry(func(attempt int) error {
|
|
u := f.Resolver.BuildURL(functionName, namespace, probePath, true)
|
|
|
|
r, _ := http.NewRequest(http.MethodGet, u, nil)
|
|
r.Header.Set("User-Agent", "com.openfaas.gateway/probe")
|
|
|
|
resp, err := http.DefaultClient.Do(r)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
log.Printf("[Probe] %s => %d", u, resp.StatusCode)
|
|
|
|
if resp.StatusCode == http.StatusOK {
|
|
return nil
|
|
}
|
|
return fmt.Errorf("failed with status: %s", resp.Status)
|
|
}, "Probe", maxCount, pollInterval)
|
|
|
|
if err != nil {
|
|
return FunctionProbeResult{
|
|
Error: err,
|
|
Available: false,
|
|
Found: true,
|
|
Duration: time.Since(start),
|
|
Updated: time.Now(),
|
|
}
|
|
}
|
|
|
|
return FunctionProbeResult{
|
|
Error: nil,
|
|
Available: true,
|
|
Found: true,
|
|
Duration: time.Since(start),
|
|
Updated: time.Now(),
|
|
}
|
|
}
|