add metrics tests

Signed-off-by: Mohammed Al Sahaf <msaa1990@gmail.com>

caddytest/spec/http/metrics/spec.hurl

@@ -0,0 +1,199 @@
+# Configure Caddy with metrics endpoint
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+	servers {
+		metrics
+	}
+}
+localhost {
+	handle /metrics {
+		metrics
+	}
+	
+	respond /hello "Hello, World!" 200
+	respond /api "API" 200
+}
+```
+
+# Metrics endpoint is accessible
+GET https://localhost:9443/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+header "Content-Type" contains "text/plain"
+
+
+# Metrics contain Caddy metrics
+GET https://localhost:9443/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body contains "caddy_"
+
+
+# Generate some traffic to record metrics
+GET https://localhost:9443/hello
+[Options]
+insecure: true
+HTTP 200
+
+GET https://localhost:9443/hello
+[Options]
+insecure: true
+HTTP 200
+
+GET https://localhost:9443/api
+[Options]
+insecure: true
+HTTP 200
+
+
+# Metrics contain HTTP metrics after requests
+GET https://localhost:9443/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body contains "caddy_http"
+
+
+# Non-metrics endpoints still work normally
+GET https://localhost:9443/hello
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Hello, World!"
+
+
+# Configure Caddy with custom metrics path
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+	servers {
+		metrics
+	}
+}
+localhost {
+	handle /custom-metrics {
+		metrics
+	}
+	
+	respond "OK" 200
+}
+```
+
+# Custom metrics path works
+GET https://localhost:9443/custom-metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+header "Content-Type" contains "text/plain"
+body contains "caddy_"
+
+
+# Default path doesn't serve metrics
+GET https://localhost:9443/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "OK"
+
+
+# Configure Caddy with disable_openmetrics option
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	handle /metrics {
+		metrics {
+			disable_openmetrics
+		}
+	}
+}
+```
+
+# Metrics work with disable_openmetrics
+GET https://localhost:9443/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+header "Content-Type" contains "text/plain"
+
+
+# Configure Caddy with metrics on specific route
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	route /internal/* {
+		metrics
+	}
+	
+	respond /public "Public" 200
+	respond "Default" 200
+}
+```
+
+# Metrics accessible on specific route
+GET https://localhost:9443/internal/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+header "Content-Type" contains "text/plain"
+
+
+# Non-metrics routes unaffected
+GET https://localhost:9443/public
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Public"
+
+
+# Default route works
+GET https://localhost:9443/
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Default"
+
+
+# POST to metrics endpoint still works
+POST https://localhost:9443/internal/metrics
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+header "Content-Type" contains "text/plain"