Add --footer flag for custom HTML footer in web UI

Allows deploying with contextual links (e.g. homepage).

2 files changed, 9 insertions, 3 deletions

diff --git a/server.go b/server.go
index eeaa42e..1fe9522 100644
--- a/server.go
+++ b/server.go
@@ -28,6 +28,7 @@ type ServeCommand struct {
 	Port      int
 	DBPath    string
 	RateLimit int
+	Footer    string
 }
 
 func (c *ServeCommand) Name() string { return "serve" }
@@ -37,6 +38,7 @@ func (c *ServeCommand) Init(args []string) error {
 	fs.IntVar(&c.Port, "port", 8080, "Port to listen on")
 	fs.StringVar(&c.DBPath, "db", "data/abvjt.db", "Path to SQLite database")
 	fs.IntVar(&c.RateLimit, "rate-limit", 30, "Max requests per minute per IP")
+	fs.StringVar(&c.Footer, "footer", "", "Custom HTML footer for the web interface")
 	if err := fs.Parse(args); err != nil {
 		if errors.Is(err, flag.ErrHelp) {
 			fs.Usage()
@@ -54,7 +56,7 @@ func (c *ServeCommand) Run(stdin io.Reader, stdout io.Writer) error {
 	}
 	defer db.Close()
 
-	http.HandleFunc("/", handleRoot())
+	http.HandleFunc("/", handleRoot(c.Footer))
 	http.HandleFunc("/api/search", handleSearch(db, c.RateLimit))
 	http.HandleFunc("/api/health", handleHealth(db, c.RateLimit))
 
@@ -99,18 +101,21 @@ func (c *ServeCommand) Run(stdin io.Reader, stdout io.Writer) error {
 	return nil
 }
 
-func handleRoot() http.HandlerFunc {
+func handleRoot(footer string) http.HandlerFunc {
 	tmpl, err := template.New("index").Parse(indexHTML)
 	if err != nil {
 		panic(fmt.Sprintf("failed to parse template: %v", err))
 	}
+	footerHTML := template.HTML(footer)
 	return func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path != "/" {
 			http.NotFound(w, r)
 			return
 		}
 		w.Header().Set("Content-Type", "text/html; charset=utf-8")
-		tmpl.Execute(w, nil)
+		tmpl.Execute(w, map[string]interface{}{
+			"Footer": footerHTML,
+		})
 	}
 }
 
diff --git a/templates/index.html b/templates/index.html
index cccd378..5426164 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -100,6 +100,7 @@
     <footer>
         <a href="/api/health">health</a> &mdash;
         data from <a href="https://wos-help.webofscience.com/WOKRS535R111/help/WOS/A_abrvjt.html">Web of Science</a>
+{{if .Footer}} &mdash; {{.Footer}}{{end}}
     </footer>
     <script>
         const form = document.getElementById('searchForm');