Add initial csaf_checker provider test

internal/testutil/testutil.go

@@ -0,0 +1,73 @@
+// This file is Free Software under the Apache-2.0 License
+// without warranty, see README.md and LICENSES/Apache-2.0.txt for details.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// SPDX-FileCopyrightText: 2023 German Federal Office for Information Security (BSI) <https://www.bsi.bund.de>
+// Software-Engineering: 2023 Intevation GmbH <https://intevation.de>
+
+// Package testutil contains shared helper functions for testing the application.
+package testutil
+
+import (
+	"html/template"
+	"net/http"
+	"os"
+	"strings"
+)
+
+// ProviderParams configures the test provider.
+type ProviderParams struct {
+	URL          string
+	EnableSha256 bool
+	EnableSha512 bool
+}
+
+// ProviderHandler returns a test provider handler with the specified configuration.
+func ProviderHandler(params *ProviderParams, directoryProvider bool) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		path := "../../testdata/"
+		if directoryProvider {
+			path += "simple-directory-provider"
+		} else {
+			path += "simple-rolie-provider"
+		}
+
+		path += r.URL.Path
+
+		if strings.HasSuffix(r.URL.Path, "/") {
+			path += "index.html"
+		}
+
+		content, err := os.ReadFile(path)
+		if err != nil {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		switch {
+		case strings.HasSuffix(path, ".html"):
+			w.Header().Add("Content-Type", "text/html")
+		case strings.HasSuffix(path, ".json"):
+			w.Header().Add("Content-Type", "application/json")
+		case strings.HasSuffix(path, ".sha256") && directoryProvider && !params.EnableSha256:
+			w.WriteHeader(http.StatusNotFound)
+			return
+		case strings.HasSuffix(path, ".sha512") && directoryProvider && !params.EnableSha512:
+			w.WriteHeader(http.StatusNotFound)
+			return
+		default:
+			w.Header().Add("Content-Type", "text/plain")
+		}
+
+		tmplt, err := template.New("base").Parse(string(content))
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+		err = tmplt.Execute(w, params)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+	}
+}