Fix #219: use deployment in Knative when cannot scale to 0

pkg/metadata/http.go

@@ -0,0 +1,131 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements.  See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to You under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License.  You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package metadata
+
+import (
+	"github.com/apache/camel-k/pkg/apis/camel/v1alpha1"
+	"regexp"
+	"strings"
+)
+
+var httpURIs = map[string]bool{
+	"ahc":                  true,
+	"ahc-ws":               true,
+	"atmosphere-websocket": true,
+	"cxf":         true,
+	"cxfrs":       true,
+	"grpc":        true,
+	"jetty":       true,
+	"netty-http":  true,
+	"netty4-http": true,
+	"rest":        true,
+	"restlet":     true,
+	"servlet":     true,
+	"spark-rest":  true,
+	"spring-ws":   true,
+	"undertow":    true,
+	"websocket":   true,
+	"knative":     true,
+}
+
+var passiveURIs = map[string]bool{
+	"bean":       true,
+	"binding":    true,
+	"browse":     true,
+	"class":      true,
+	"controlbus": true,
+	"dataformat": true,
+	"dataset":    true,
+	"direct":     true,
+	"direct-vm":  true,
+	"language":   true,
+	"log":        true,
+	"mock":       true,
+	"properties": true,
+	"ref":        true,
+	"seda":       true,
+	"stub":       true,
+	"test":       true,
+	"validator":  true,
+	"vm":         true,
+}
+
+var restIndicator = regexp.MustCompile(".*rest\\s*\\([^)]*\\).*")
+var xmlRestIndicator = regexp.MustCompile(".*<\\s*rest\\s+[^>]*>.*")
+
+// requiresHTTPService returns true if the integration needs to expose itself through HTTP
+func requiresHTTPService(source v1alpha1.SourceSpec, fromURIs []string) bool {
+	if hasRestIndicator(source) {
+		return true
+	}
+	return containsHTTPURIs(fromURIs)
+}
+
+// hasOnlyPassiveEndpoints returns true if the integration has no endpoint that needs to remain always active
+func hasOnlyPassiveEndpoints(source v1alpha1.SourceSpec, fromURIs []string) bool {
+	passivePlusHTTP := make(map[string]bool)
+	for k, v := range passiveURIs {
+		passivePlusHTTP[k] = v
+	}
+	for k, v := range httpURIs {
+		passivePlusHTTP[k] = v
+	}
+	return containsOnlyURIsIn(fromURIs, passivePlusHTTP)
+}
+
+func containsHTTPURIs(fromURI []string) bool {
+	for _, uri := range fromURI {
+		prefix := getURIPrefix(uri)
+		if enabled, ok := httpURIs[prefix]; ok && enabled {
+			return true
+		}
+	}
+	return false
+}
+
+func containsOnlyURIsIn(fromURI []string, allowed map[string]bool) bool {
+	for _, uri := range fromURI {
+		prefix := getURIPrefix(uri)
+		if enabled, ok := allowed[prefix]; !ok || !enabled {
+			return false
+		}
+	}
+	return true
+}
+
+func getURIPrefix(uri string) string {
+	parts := strings.SplitN(uri, ":", 2)
+	if len(parts) > 0 {
+		return parts[0]
+	}
+	return ""
+}
+
+func hasRestIndicator(source v1alpha1.SourceSpec) bool {
+	pat := getRestIndicatorRegexpsForLanguage(source.Language)
+	return pat.MatchString(source.Content)
+}
+
+func getRestIndicatorRegexpsForLanguage(language v1alpha1.Language) *regexp.Regexp {
+	switch language {
+	case v1alpha1.LanguageXML:
+		return xmlRestIndicator
+	default:
+		return restIndicator
+	}
+}

pkg/metadata/metadata.go

@@ -19,19 +19,68 @@ package metadata
 
 import (
 	"github.com/apache/camel-k/pkg/apis/camel/v1alpha1"
+	"sort"
 )
 
+// ExtractAll returns metadata information from all listed source codes
+func ExtractAll(sources []v1alpha1.SourceSpec) IntegrationMetadata {
+	// neutral metadata
+	meta := IntegrationMetadata{
+		Language:            "",
+		Dependencies:        []string{},
+		FromURIs:            []string{},
+		ToURIs:              []string{},
+		PassiveEndpoints:    true,
+		RequiresHTTPService: false,
+	}
+	for _, source := range sources {
+		meta = merge(meta, Extract(source))
+	}
+	return meta
+}
+
+func merge(m1 IntegrationMetadata, m2 IntegrationMetadata) IntegrationMetadata {
+	language := m2.Language
+	if m1.Language != "" && m1.Language != language {
+		language = ""
+	}
+	deps := make(map[string]bool)
+	for _, d := range m1.Dependencies {
+		deps[d] = true
+	}
+	for _, d := range m2.Dependencies {
+		deps[d] = true
+	}
+	allDependencies := make([]string, 0)
+	for k := range deps {
+		allDependencies = append(allDependencies, k)
+	}
+	sort.Strings(allDependencies)
+	return IntegrationMetadata{
+		Language:            language,
+		FromURIs:            append(m1.FromURIs, m2.FromURIs...),
+		ToURIs:              append(m1.ToURIs, m2.ToURIs...),
+		Dependencies:        allDependencies,
+		RequiresHTTPService: m1.RequiresHTTPService || m2.RequiresHTTPService,
+		PassiveEndpoints:    m1.PassiveEndpoints && m2.PassiveEndpoints,
+	}
+}
+
 // Extract returns metadata information from the source code
 func Extract(source v1alpha1.SourceSpec) IntegrationMetadata {
 	language := discoverLanguage(source)
 	fromURIs := discoverFromURIs(source, language)
 	toURIs := discoverToURIs(source, language)
 	dependencies := discoverDependencies(source, fromURIs, toURIs)
+	requiresHTTPService := requiresHTTPService(source, fromURIs)
+	passiveEndpoints := hasOnlyPassiveEndpoints(source, fromURIs)
 	return IntegrationMetadata{
-		Language:     language,
-		FromURIs:     fromURIs,
-		ToURIs:       toURIs,
-		Dependencies: dependencies,
+		Language:            language,
+		FromURIs:            fromURIs,
+		ToURIs:              toURIs,
+		Dependencies:        dependencies,
+		RequiresHTTPService: requiresHTTPService,
+		PassiveEndpoints:    passiveEndpoints,
 	}
 }