wavehunter: add QMDL storage

Instead of reading/writing to a single QMDL file, we now can manage
a directory of several files, and have the ability to start/stop writing
to them on the fly.

This commit also adds graceful exiting to the server, so we can perform
cleanup steps when the server's exiting.

wavehunter/static/js/main.js

@@ -1,24 +1,90 @@
 async function populateDivs() {
     const systemStats = await getSystemStats();
-    const diagStats = await getDiagStats();
-
     const systemStatsDiv = document.getElementById('system-stats');
-    const diagStatsDiv = document.getElementById('diag-stats');
-
     systemStatsDiv.innerHTML = JSON.stringify(systemStats, null, 2);
-    diagStatsDiv.innerHTML = JSON.stringify(diagStats, null, 2);
+
+    const qmdlManifest = await getQmdlManifest();
+    updateQmdlManifestTable(qmdlManifest);
+}
+
+function updateQmdlManifestTable(manifest) {
+    const table = document.getElementById('qmdl-manifest-table');
+    const numRows = table.rows.length;
+    for (let i=1; i<numRows; i++) {
+        table.deleteRow(1);
+    }
+    if (manifest.current_entry) {
+        const row = createEntryRow(manifest.current_entry);
+        row.classList.add('current');
+        table.appendChild(row)
+    }
+    for (let entry of manifest.entries) {
+        table.appendChild(createEntryRow(entry));
+    }
+}
+
+function createEntryRow(entry) {
+    const row = document.createElement('tr');
+    const name = document.createElement('th');
+    name.scope = 'row';
+    name.innerText = entry.name;
+    row.appendChild(name);
+    for (const key of ['start_time', 'end_time', 'size_bytes']) {
+        const td = document.createElement('td');
+        td.innerText = entry[key];
+        row.appendChild(td);
+    }
+    const pcap_td = document.createElement('td');
+    const pcap_link = document.createElement('a');
+    pcap_link.href = `/api/pcap/${entry.name}`;
+    pcap_link.innerText = 'pcap';
+    pcap_td.appendChild(pcap_link);
+    row.appendChild(pcap_td);
+    const qmdl_td = document.createElement('td');
+    const qmdl_link = document.createElement('a');
+    qmdl_link.href = `/api/qmdl/${entry.name}`;
+    qmdl_link.innerText = 'qmdl';
+    qmdl_td.appendChild(qmdl_link);
+    row.appendChild(qmdl_td);
+    return row;
 }
 
 async function getSystemStats() {
-    return await getJson('/api/system-stats');
+    return JSON.parse(await req('GET', '/api/system-stats'));
 }
 
-async function getDiagStats() {
-    return await getJson('/api/diag-stats');
+async function getQmdlManifest() {
+    const manifest = JSON.parse(await req('GET', '/api/qmdl-manifest'));
+    if (manifest.current_entry) {
+        manifest.current_entry.start_time = new Date(manifest.current_entry.start_time);
+    }
+    for (entry of manifest.entries) {
+        entry.start_time = new Date(entry.start_time);
+        entry.end_time = new Date(entry.end_time);
+    }
+    // sort them in reverse chronological order
+    manifest.entries.reverse();
+    return manifest;
 }
 
-async function getJson(url) {
-    const response = await fetch(url);
-    const data = await response.json();
-    return data;
+async function startRecording() {
+    await req('POST', '/api/start-recording');
+    populateDivs();
+}
+
+async function stopRecording() {
+    await req('POST', '/api/stop-recording');
+    populateDivs();
+}
+
+async function req(method, url) {
+    const response = await fetch(url, {
+        method: method,
+    });
+    const body = await response.text();
+    if (response.status >= 200 && response.status < 300) {
+        return body;
+    } else {
+        throw new Error(body);
+    }
 }