Generation of micropython image with frozen modules

src/app_loader.py

@@ -118,7 +118,7 @@ async def update_app(mqtt, name):
         version_sub.unsubscribe()
 
         if current_app != name or current_version != latest:
-            mqtt.log('installed: {} v{}, want {} v{}'.format(
+            mqtt.log('Current: {} v{}, want {} v{}'.format(
                 current_app, current_version, name, latest))
             try:
                 # if the wrong app is installed, we remove it and reboot to
@@ -134,6 +134,9 @@ async def update_app(mqtt, name):
             app_size = await sub.wait_for_value()
             sub.unsubscribe()
             mqtt.log('Installed {} v{}, {}b'.format(name, latest, app_size))
+
+            install_dependencies(mqtt)
+
             return True
     except Exception as e:
         mqtt.log('Update error:', e)
@@ -142,6 +145,37 @@ async def update_app(mqtt, name):
     return False
 
 
+def install_dependencies(mqtt):
+    import app
+    try:
+        deps = app.DEPENDENCIES
+        mqtt.log('Installing {} dependencies'.format(len(deps)))
+        for d in deps:
+            gc.collect()
+            if len(d) == 1:  # upip package
+                mqtt.log('  - upip package {}'.format(d))
+                import upip
+                upip.install(d)
+            elif len(d) == 2:  # file path, source URL
+                path, url = d
+                mqtt.log('  - dependency {} from {}'.format(path, url))
+                gc.collect()
+                import upip
+                f = upip.url_open(url)
+                buf = bytearray(128)
+                view = memoryview(buf)
+                with open(path, 'wb') as outfile:
+                    while True:
+                        n_read = f.readinto(buf)
+                        if n_read == 0:
+                            break
+                        outfile.write(view[:n_read])
+            gc.collect()
+    except Exception as e:
+        mqtt.log('Error installing dependencies: ', e)
+
+
+
 def deepsleep(duration_ms):
     utime.sleep_ms(200)
     # configure RTC.ALARM0 to be able to wake the device