Split monolithic rule into per-test rules, collect gathers facts only

checker/rules_reachability.go

@@ -0,0 +1,48 @@
+package checker
+
+import (
+	"context"
+	"fmt"
+
+	sdk "git.happydns.org/checker-sdk-go/checker"
+)
+
+// reachabilityRule flags endpoints that did not accept a TCP connection.
+type reachabilityRule struct{}
+
+func (r *reachabilityRule) Name() string { return "tls.reachability" }
+func (r *reachabilityRule) Description() string {
+	return "Verifies that every discovered TLS endpoint accepts a TCP connection."
+}
+
+func (r *reachabilityRule) Evaluate(ctx context.Context, obs sdk.ObservationGetter, _ sdk.CheckerOptions) []sdk.CheckState {
+	data, errSt := loadData(ctx, obs)
+	if errSt != nil {
+		return []sdk.CheckState{*errSt}
+	}
+	if len(data.Probes) == 0 {
+		return []sdk.CheckState{emptyCaseState("tls.reachability.no_endpoints")}
+	}
+
+	var out []sdk.CheckState
+	for _, ref := range sortedRefs(data) {
+		p := data.Probes[ref]
+		if p.TCPError == "" {
+			continue
+		}
+		out = append(out, sdk.CheckState{
+			Status:  sdk.StatusCrit,
+			Code:    "tls.reachability.tcp_unreachable",
+			Subject: subjectOf(p),
+			Message: fmt.Sprintf("Cannot open TCP connection to %s: %s", p.Endpoint, p.TCPError),
+			Meta:    metaOf(p),
+		})
+	}
+	if len(out) == 0 {
+		return []sdk.CheckState{passState(
+			"tls.reachability.ok",
+			"All discovered endpoints accepted a TCP connection.",
+		)}
+	}
+	return out
+}