lots of fun initial progress!

interface/resources/qml/hifi/commerce/checkout/Checkout.qml

@@ -146,7 +146,8 @@ Rectangle {
     }
 
     onItemTypeChanged: {
-        if (root.itemType === "entity" || root.itemType === "wearable" || root.itemType === "contentSet" || root.itemType === "avatar") {
+        if (root.itemType === "entity" || root.itemType === "wearable" ||
+            root.itemType === "contentSet" || root.itemType === "avatar" || root.itemType === "app") {
             root.isCertified = true;
         } else {
             root.isCertified = false;
@@ -679,7 +680,7 @@ Rectangle {
             id: rezNowButton;
             enabled: (root.itemType === "entity" && root.canRezCertifiedItems) ||
                 (root.itemType === "contentSet" && Entities.canReplaceContent()) ||
-                root.itemType === "wearable" || root.itemType === "avatar";
+                root.itemType === "wearable" || root.itemType === "avatar" || root.itemType === "app";
             buttonGlyph: (root.buttonGlyph)[itemTypesArray.indexOf(root.itemType)];
             color: hifi.buttons.red;
             colorScheme: hifi.colorSchemes.light;
@@ -712,6 +713,9 @@ Rectangle {
                     lightboxPopup.button2text = "CONFIRM";
                     lightboxPopup.button2method = "MyAvatar.useFullAvatarURL('" + root.itemHref + "'); root.visible = false;";
                     lightboxPopup.visible = true;
+                } else if (root.itemType === "app") {
+                    // "Run" button is separate.
+                    Commerce.installApp(root.itemHref);
                 } else {
                     sendToScript({method: 'checkout_rezClicked', itemHref: root.itemHref, itemType: root.itemType});
                     rezzedNotifContainer.visible = true;

interface/resources/qml/hifi/commerce/purchases/PurchasedItem.qml

@@ -506,6 +506,9 @@ Item {
                     sendToPurchases({method: 'showReplaceContentLightbox', itemHref: root.itemHref});
                 } else if (root.itemType === "avatar") {
                     sendToPurchases({method: 'showChangeAvatarLightbox', itemName: root.itemName, itemHref: root.itemHref});
+                } else if (root.itemType === "app") {
+                    // "Run" and "Uninstall" buttons are separate.
+                    Commerce.installApp(root.itemHref);
                 } else {
                     sendToPurchases({method: 'purchases_rezClicked', itemHref: root.itemHref, itemType: root.itemType});
                     root.showConfirmation = true;

interface/src/commerce/QmlCommerce.cpp

@@ -10,6 +10,7 @@
 //
 
 #include "QmlCommerce.h"
+#include "CommerceLogging.h"
 #include "Application.h"
 #include "DependencyManager.h"
 #include "Ledger.h"
@@ -17,6 +18,7 @@
 #include <AccountManager.h>
 #include <Application.h>
 #include <UserActivityLogger.h>
+#include <ScriptEngines.h>
 
 QmlCommerce::QmlCommerce() {
     auto ledger = DependencyManager::get<Ledger>();
@@ -183,3 +185,100 @@ void QmlCommerce::alreadyOwned(const QString& marketplaceId) {
     auto ledger = DependencyManager::get<Ledger>();
     ledger->alreadyOwned(marketplaceId);
 }
+
+static QString APP_PATH = PathUtils::getAppDataPath() + "apps";
+bool QmlCommerce::isAppInstalled(const QString& itemHref) {
+    QUrl appHref(itemHref);
+
+    QFileInfo appFile(APP_PATH + "/" + appHref.fileName());
+    if (appFile.exists() && appFile.isFile()) {
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool QmlCommerce::installApp(const QString& itemHref) {
+    if (!QDir(APP_PATH).exists()) {
+        if (!QDir().mkdir(APP_PATH)) {
+            qCDebug(commerce) << "Couldn't make APP_PATH directory.";
+            return false;
+        }
+    }
+
+    QUrl appHref(itemHref);
+
+    auto request =
+        std::unique_ptr<ResourceRequest>(DependencyManager::get<ResourceManager>()->createResourceRequest(this, appHref));
+
+    if (!request) {
+        qCDebug(commerce) << "Couldn't create resource request for app.";
+        return false;
+    }
+
+    QEventLoop loop;
+    connect(request.get(), &ResourceRequest::finished, &loop, &QEventLoop::quit);
+    request->send();
+    loop.exec();
+
+    if (request->getResult() != ResourceRequest::Success) {
+        qCDebug(commerce) << "Failed to get .app.json file from remote.";
+        return false;
+    }
+
+    // Copy the .app.json to the apps directory inside %AppData%/High Fidelity/Interface
+    auto requestData = request->getData();
+    QFile appFile(APP_PATH + "/" + appHref.fileName());
+    if (!appFile.open(QIODevice::WriteOnly)) {
+        qCDebug(commerce) << "Couldn't open local .app.json file for creation.";
+        return false;
+    }
+    if (appFile.write(requestData) == -1) {
+        qCDebug(commerce) << "Couldn't write to local .app.json file.";
+        return false;
+    }
+    // Close the file
+    appFile.close();
+
+    // Read from the returned datastream to know what .js to add to Running Scripts
+    QJsonDocument appFileJsonDocument = QJsonDocument::fromJson(requestData);
+    QJsonObject appFileJsonObject = appFileJsonDocument.object();
+    QString scriptUrl = appFileJsonObject["scriptURL"].toString();
+
+    if ((DependencyManager::get<ScriptEngines>()->loadScript(scriptUrl.trimmed())).isNull()) {
+        qCDebug(commerce) << "Couldn't load script.";
+        return false;
+    }
+
+    emit appInstalled(appHref.fileName());
+    return true;
+}
+
+bool QmlCommerce::uninstallApp(const QString& itemHref) {
+    QUrl appHref(itemHref);
+
+    // Read from the file to know what .js script to stop
+    QFile appFile(APP_PATH + "/" + appHref.fileName());
+    if (!appFile.open(QIODevice::ReadOnly)) {
+        qCDebug(commerce) << "Couldn't open local .app.json file for deletion.";
+        return false;
+    }
+    QJsonDocument appFileJsonDocument = QJsonDocument::fromJson(appFile.readAll());
+    QJsonObject appFileJsonObject = appFileJsonDocument.object();
+    QString scriptUrl = appFileJsonObject["scriptURL"].toString();
+
+    if (!DependencyManager::get<ScriptEngines>()->stopScript(scriptUrl.trimmed(), false)) {
+        qCDebug(commerce) << "Couldn't stop script.";
+        return false;
+    }
+
+    // Delete the .app.json from the filesystem
+    // remove() closes the file first.
+    if (!appFile.remove()) {
+        qCDebug(commerce) << "Couldn't delete local .app.json file.";
+        return false;
+    }
+
+    emit appUninstalled(appHref.fileName());
+    return true;
+}

interface/src/commerce/QmlCommerce.h

@@ -51,6 +51,9 @@ signals:
 
     void contentSetChanged(const QString& contentSetHref);
 
+    void appInstalled(const QString& appFileName);
+    void appUninstalled(const QString& appFileName);
+
 protected:
     Q_INVOKABLE void getWalletStatus();
 
@@ -76,8 +79,11 @@ protected:
     Q_INVOKABLE void transferHfcToNode(const QString& nodeID, const int& amount, const QString& optionalMessage);
     Q_INVOKABLE void transferHfcToUsername(const QString& username, const int& amount, const QString& optionalMessage);
 
-
     Q_INVOKABLE void replaceContentSet(const QString& itemHref);
+
+    Q_INVOKABLE bool isAppInstalled(const QString& itemHref);
+    Q_INVOKABLE bool installApp(const QString& itemHref);
+    Q_INVOKABLE bool uninstallApp(const QString& itemHref);
 };
 
 #endif // hifi_QmlCommerce_h

scripts/system/marketplaces/marketplaces.js

@@ -551,11 +551,11 @@ var selectionDisplay = null; // for gridTool.js to ignore
                 break;
             case 'checkout_rezClicked':
             case 'purchases_rezClicked':
-                if (message.itemType === "app") {
-                    console.log("How did you get here? You can't buy apps yet!");
-                } else {
-                    rezEntity(message.itemHref, message.itemType);
-                }
+                rezEntity(message.itemHref, message.itemType);
+                break;
+            case 'checkout_installClicked':
+            case 'purchases_installClicked':
+                
                 break;
             case 'header_marketplaceImageClicked':
             case 'purchases_backClicked':