1 files changed, 30 insertions, 0 deletions
diff --git a/web/src/js/components/Header/ConnectionIndicator.jsx b/web/src/js/components/Header/ConnectionIndicator.jsx
new file mode 100644
index 00000000..1ee42e25
--- /dev/null
+++ b/web/src/js/components/Header/ConnectionIndicator.jsx
@@ -0,0 +1,30 @@
+import React from "react"
+import PropTypes from "prop-types"
+import { connect } from "react-redux"
+import { ConnectionState } from "../../ducks/connection"
+
+
+ConnectionIndicator.propTypes = {
+    state: PropTypes.symbol.isRequired,
+    message: PropTypes.string,
+
+}
+function ConnectionIndicator({ state, message }) {
+    switch (state) {
+        case ConnectionState.INIT:
+            return <span className="connection-indicator init">connecting…</span>;
+        case ConnectionState.FETCHING:
+            return <span className="connection-indicator fetching">fetching data…</span>;
+        case ConnectionState.ESTABLISHED:
+            return <span className="connection-indicator established">connected</span>;
+        case ConnectionState.ERROR:
+            return <span className="connection-indicator error"
+                         title={message}>connection lost</span>;
+        case ConnectionState.OFFLINE:
+            return <span className="connection-indicator offline">offline</span>;
+    }
+}
+
+export default connect(
+    state => state.connection,
+)(ConnectionIndicator)