move ui to using trunk

cargo install trunk

ui/js/Downloads.js

@@ -0,0 +1,70 @@
+const Downloads = {
+    props: [ 'kind', 'name', 'token', 'state' ],
+    data() {
+        return { createDisabled: false, selectedAssets: {} }
+    },
+    computed: {
+        availableAssets() {
+            return {
+                cluster: ['addons'],
+                host: [
+                    "kernel",
+                    "initrd",
+                    "bootstrap.tar",
+                    "boot.img.lz4",
+                    "boot.img.gz",
+                    "boot.qcow2",
+                    "boot.vmdk",
+                    "boot.img",
+                    "boot.iso",
+                    "boot.tar",
+                    "boot-efi.tar",
+                    "config",
+                    "bootstrap-config",
+                    "ipxe",
+                ],
+            }[this.kind]
+        },
+        downloads() {
+            return Object.entries(this.state.Downloads)
+              .filter(e => { let d=e[1]; return d.Kind == this.kind && d.Name == this.name })
+              .map(e => {
+                const token= e[0];
+                return {
+                  text: token.substring(0, 5) + '...',
+                  url: '/public/downloads/'+token+"/",
+                }
+              })
+        },
+        assets() {
+            return this.availableAssets.filter(a => this.selectedAssets[a])
+        },
+    },
+    methods: {
+        createToken() {
+            event.preventDefault()
+            this.createDisabled = true
+
+            fetch('/authorize-download', {
+                method: 'POST',
+                body: JSON.stringify({Kind: this.kind, Name: this.name, Assets: this.assets}),
+                headers: { 'Authorization': 'Bearer ' + this.token, 'Content-Type': 'application/json' },
+            }).then((resp) => resp.json())
+              .then((token) => { this.selectedAssets = {}; this.createDisabled = false })
+              .catch((e) => { alert('failed to create link'); this.createDisabled = false })
+        },
+    },
+    template: `
+  <h4>Available assets</h4>
+  <p class="downloads">
+    <template v-for="asset in availableAssets">
+      <label :class="{selected: selectedAssets[asset]}"><input type="checkbox" v-model="selectedAssets[asset]" />&nbsp;{{ asset }}</label>
+      {{" "}}
+    </template>
+  </p>
+  <p><button :disabled="createDisabled || assets.length==0" @click="createToken">Create link</button></p>
+  <template v-if="downloads.length">
+    <h4>Active links</h4>
+    <p class="download-links"><template v-for="d in downloads"><a :href="d.url" target="_blank">{{ d.text }}</a>{{" "}}</template></p>
+  </template>`
+}