cloudapi: use Recover middleware to handle panics

recover from panics such as out-of-bounds array access & nil
pointer access, print a stack trace and return 5xx error
instead of the service crashing and relying on Execution
framework to handle crashes

vendor/github.com/labstack/echo/v4/middleware/util.go

@@ -0,0 +1,54 @@
+package middleware
+
+import (
+	"strings"
+)
+
+func matchScheme(domain, pattern string) bool {
+	didx := strings.Index(domain, ":")
+	pidx := strings.Index(pattern, ":")
+	return didx != -1 && pidx != -1 && domain[:didx] == pattern[:pidx]
+}
+
+// matchSubdomain compares authority with wildcard
+func matchSubdomain(domain, pattern string) bool {
+	if !matchScheme(domain, pattern) {
+		return false
+	}
+	didx := strings.Index(domain, "://")
+	pidx := strings.Index(pattern, "://")
+	if didx == -1 || pidx == -1 {
+		return false
+	}
+	domAuth := domain[didx+3:]
+	// to avoid long loop by invalid long domain
+	if len(domAuth) > 253 {
+		return false
+	}
+	patAuth := pattern[pidx+3:]
+
+	domComp := strings.Split(domAuth, ".")
+	patComp := strings.Split(patAuth, ".")
+	for i := len(domComp)/2 - 1; i >= 0; i-- {
+		opp := len(domComp) - 1 - i
+		domComp[i], domComp[opp] = domComp[opp], domComp[i]
+	}
+	for i := len(patComp)/2 - 1; i >= 0; i-- {
+		opp := len(patComp) - 1 - i
+		patComp[i], patComp[opp] = patComp[opp], patComp[i]
+	}
+
+	for i, v := range domComp {
+		if len(patComp) <= i {
+			return false
+		}
+		p := patComp[i]
+		if p == "*" {
+			return true
+		}
+		if p != v {
+			return false
+		}
+	}
+	return false
+}