feat: Make API endpoint configurable (#29)

## Which problem is this PR solving?
Make API endpoint configurable, this will be required for deploying to
our own environments since they point at different API endpoints.

## Short description of the changes
- Add `HONEYCOMB_API_ENDPOINT` configuration variable

## How to verify that this has the expected result
- Use the new environment variable to send data to Honeycomb's dogfood
environment

---------

Co-authored-by: Mike Goldsmith <goldsmith.mike@gmail.com>
Co-authored-by: Vera Reynolds <vreynolds@users.noreply.github.com>

deployment.yaml

@@ -43,8 +43,8 @@ spec:
     spec:
       containers:
         - name: hny-ebpf-agent
-          # image: hny/ebpf-agent:local
-          image: ghcr.io/honeycombio/ebpf-agent:dev
+          image: hny/ebpf-agent:local
+          # image: ghcr.io/honeycombio/ebpf-agent:dev
           imagePullPolicy: IfNotPresent
           env:
             - name: HONEYCOMB_API_KEY
@@ -54,6 +54,8 @@ spec:
                   key: api-key
             - name: HONEYCOMB_DATASET
               value: ebpf-agent-go
+            - name: HONEYCOMB_API_ENDPOINT
+              value: $HONEYCOMB_API_ENDPOINT
           securityContext:
             capabilities:
               add:

main.go

@@ -20,11 +20,12 @@ func main() {
 		log.Fatalf("Failed to get host kernel version: %v", err)
 	}
 	log.Printf("Host kernel version: %s\n", kernelVersion)
-
+	log.Printf("Honeycomb API endpoint: %s\n", os.Getenv("HONEYCOMB_API_ENDPOINT"))
 	// setup libhoney
 	libhoney.Init(libhoney.Config{
-		APIKey: os.Getenv("HONEYCOMB_API_KEY"),
+		APIKey:  os.Getenv("HONEYCOMB_API_KEY"),
 		Dataset: os.Getenv("HONEYCOMB_DATASET"),
+		APIHost: os.Getenv("HONEYCOMB_API_ENDPOINT"),
 	})
 	defer libhoney.Close()