How do I use Alexa APL video components? - aws-lambda

Question

I'm writing an Alexa app and setting up multi-modal responses using the 'RenderDocumentDirective' in the python SDK.
For info I'm using an AWS hosted skill in a lambda function.
I'm using RddAPL to add the APL and RddAPLA to add the APLA.
The APLA works fine. The APL has stopped working and I don't know why. I had this working earlier and now I can't work out what is wrong. There are no error messages in the console.
The APLA template works so this is not a permissions issue and it worked. I just don't know what's changed. If I remove the RddAPL directive then everything works fine.
Can you help me review the APL sections to see if there is an error?
Here is the function setting the apl documents:
import config
if config.vars.APL_SUPPORTED == True:
config.apl.DOCUMENT = 'apl/myAPL.json'
config.apl.APLA_DOCUMENT = 'apl/myAPLA.json'
Here is the function calling the apl documents:
import config
from ask_sdk_model.interfaces.alexa.presentation.apl import (
RenderDocumentDirective as RddAPL)
from ask_sdk_model.interfaces.alexa.presentation.apla import (
RenderDocumentDirective as RddAPLA)
def load_apl_document(file_path):
with open(file_path) as f:
return json.load(f)
def myResponse(handler_input, speak_output):
if config.vars.APL_SUPPORTED == True:
#creates url for video
videoUrl = create_presigned_url("video/myvideo.mp4")
handler_input.response_builder.add_directive(
RddAPL(
token = 'myToken',
document = load_apl_document(config.apl.DOCUMENT),
datasources = {
"videoUrl": videoUrl
}
)
)
#creates url for audio
audioUrl = create_presigned_url("audio/myaudio.mp3")
handler_input.response_builder.add_directive(
RddAPLA(
token = 'myToken',
document = load_apl_document(config.apl.APLA_DOCUMENT),
datasources = {
"speech": speak_output,
"audioUrl": audioUrl
}
)
)
return (
handler_input.response_builder
.set_should_end_session(False)
.response
)
else:
return (
handler_input.response_builder
.speak(speak_output)
.set_should_end_session(False)
.response
)
and these are the associated JSON files:
{
"type": "APL",
"version": "1.8",
"license": "Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.\nSPDX-License-Identifier: LicenseRef-.amazon.com.-AmznSL-1.0\nLicensed under the Amazon Software License http://aws.amazon.com/asl/",
"settings": {},
"theme": "dark",
"import": [],
"resources": [],
"styles": {},
"onMount": [],
"graphics": {},
"commands": {},
"layouts": {},
"mainTemplate": {
"parameters": [
"payload"
],
"items": [
{
"items": [
{
"source": "${payload.videoUrl}",
"autoplay": true,
"type": "Video",
"width": "100%",
"height": "100%"
}
],
"layoutDirection": "inherit",
"alignItems": "center",
"type": "Container",
"width": "100%",
"height": "100%"
}
]
}
}
{
"type": "APLA",
"version": "0.91",
"mainTemplate": {
"parameters": [
"payload"
],
"item": [
{
"type": "Mixer",
"items": [
{
"type": "Sequencer",
"items": [
{
"type": "Audio",
"description": "The Audio component plays the provided audio file, such as an MP3 file. See docs for more information.",
"source": "soundbank://soundlibrary/a_sound_from_the_library"
},
{
"type": "Speech",
"content": "${payload.speech}"
}
]
},
{
"type": "Audio",
"source": "${payload.audioUrl}",
"duration": "trimToParent",
"filter": [
{
"type": "Volume",
"amount": "50%"
},
{
"type": "FadeOut",
"duration": 2000
}
]
}
]
}
]
}
}

Answer 1

After hours of testing, I realised that you need a file __init__.py in the folder holding the .json apl templates.

Answer 2

My last answer is actually incorrect.
This is the text from the APL for audio dev documentation, which explains how the APL document differs:
Note: For APL for Audio, use the payload parameter to bind the entire datasources object to your document. This is different from APL 1.3 for screen devices, where you can bind the mainTemplate.parameters parameter to the name of the data source instead.
I've therefore changed my code as follows:
The APL .json
{
"type": "APL",
"version": "1.8",
"license": "Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.\nSPDX-License-Identifier: LicenseRef-.amazon.com.-AmznSL-1.0\nLicensed under the Amazon Software License http://aws.amazon.com/asl/",
"settings": {},
"theme": "dark",
"import": [],
"resources": [],
"styles": {},
"onMount": [],
"graphics": {},
"commands": {},
"layouts": {},
"mainTemplate": {
"parameters": [
"myDocumentData"
],
"items": [
{
"items": [
{
"source": "${myDocumentData.videoUrl}",
"autoplay": true,
"type": "Video",
"width": "100%",
"height": "100%"
}
],
"layoutDirection": "inherit",
"alignItems": "center",
"type": "Container",
"width": "100%",
"height": "100%"
}
]
}
}
and the datasource:
#creates url for video
videoUrl = create_presigned_url("video/myvideo.mp4")
handler_input.response_builder.add_directive(
RddAPL(
token = 'myToken',
document = load_apl_document(config.apl.DOCUMENT),
datasources = {
myDocumentData: {
"videoUrl": videoUrl
}
}
)
)