Lambda Container Images

With the recent AWS announcement of container images support for AWS Lambda, a machine learning developer can take advantage of up to 10 GB storage to deploy Deep Learning Models (Pytorch, Tensorflow) or more robust Decision Tree Models like the XGBoost library.

You can find on this repo examples deploying an XGBoost model and a Pytorch model. All the AWS infrastructure is automatically provisioned using AWS CloudFormation and AWS Sam. Additionally, a bash pipeline (pipeline.sh) is included to create the AWS resources needed, you can adapt it to your CI/CD service.

Note. Make sure you have awscli and aws-sam-cli installed and configured in your system. For more information go here.

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Pytorch Example

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1. Create an ECR Registry and an S3 Bucket

The first AWS services that we need to provision are an ECR Registry to push the docker images to and an S3 bucket to store the model artifacts and the stack's files.

Export the following environment variables with appropiate names

• TEMPLATE_REGISTRY (the stack's name of your registry).

• TEMPLATE_LAMBDA (the stack's name of your lambda).

• PREFIX_LAMBDA (s3 bucket key to upload lambda stack artifacts).

• CAPABILITIES (Capability type to create AWS stack, run sam deploy --help for more info).

For instance,

export TEMPLATE_REGISTRY="pytorch-example"
export TEMPLATE_LAMBDA="pytorch-lambda"
export PREFIX_LAMBDA="sam_templates/pytorch-lambda"
export CAPABILITIES="CAPABILITY_NAMED_IAM"

and run

bash pipeline.sh -s <stage> -r

where <stage> refers to the development stage (i.e. dev, stage, prod).

Note. By default, the S3 Bucket takes the following name: "${Project}-<stage>-${AWS::AccountId}". You can modify this name in the registry.yaml file.

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2. Deploying the Pytorch Model

TL: DR
On your terminal run

bash pipeline.sh -s <stage> -d ./pytorch-example

2.A The Dockerfile

By default the Dockerfile uses python:3.6-buster image, a newer python version can be set changing the variable RUNTIME_VERSION inside the /pytorch-example/DockerFile.

This base image must implement the Lambda Runtime API awslambdaric, the docs suggest the following

The container image must implement the Lambda Runtime API. The AWS open-source runtime interface clients implement the API. You can add a runtime interface client to your preferred base image to make it compatible with Lambda.

2.B Load the Pytorch model

The pretrained model (Mobilenet V2) is loaded from the function directory of the container. Optionally you can use boto3 to retrieve the model from an S3 bucket.

2.C The deployment step

Run the deploy step as follows

bash pipeline.sh -s <stage> -d <path>

where the <path> argument (defaults to current paht) refers to the directory where the Dockerfile and the app is located

For instance,

bash pipeline.sh -s dev -d ./pytorch-example

**Note **: This will fail if you have not already run the -r flag in the pipeline.sh. Alternatively you can run them together: bash pipeline.sh -s <stage> -r -d <path>

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4. Get Predictions

Note: As the docker images contains awslambdaric, you can test the Docker container locally, refer to this instructions for more details.

Pytorch offers some pretrained models with code example Implementations. In this example, we're using Mobilenet V2 to identify a dog's breed.

For this, the API endpoint expects the user to pass a valid public Url of a dog's image and a number of dog's match.

curl -XPOST "here_goes_your_api_url" -H 'Content-Type: application/json' -d '{"input_url": "https://github.com/pytorch/hub/raw/master/images/dog.jpg", "n_predictions":5}'

where you can retrieve here_goes_your_api_url from the output of the lambda stack (template.yaml), see image below.

Expected result:

[["Samoyed, Samoyede", 83.03044128417969], ["Pomeranian", 6.988767623901367], ["keeshond", 1.2964094877243042], ["collie", 1.0797767639160156], ["Great Pyrenees", 0.9886746406555176]]

or input any publicly avaible dog image

curl -XPOST "here_goes_your_api_url" -H 'Content-Type: application/json' -d '{"input_url": "https://www.thesprucepets.com/thmb/sfuyyLvyUx636_Oq3Fw5_mt-PIc=/3760x2820/smart/filters:no_upscale()/adorable-white-pomeranian-puppy-spitz-921029690-5c8be25d46e0fb000172effe.jpg", "n_predictions":10}'

with result

[["Pomeranian", 61.879791259765625], ["Maltese dog, Maltese terrier, Maltese", 13.713523864746094], ["Samoyed, Samoyede", 8.831860542297363], ["Arctic fox, white fox, Alopex lagopus", 3.6575238704681396], ["Japanese spaniel", 2.2257049083709717], ["keeshond", 2.205970048904419], ["papillon", 1.0087969303131104], ["barrow, garden cart, lawn cart, wheelbarrow", 0.5974907279014587], ["Pekinese, Pekingese, Peke", 0.5239897966384888], ["Chihuahua", 0.2706214189529419]]

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XGBoost Example

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1. Setting up AWS Resources

Configure the stacks with an appropiate name. For XGBoost, we can set the following set of variables

export TEMPLATE_REGISTRY="xgboost-registry-example"
export TEMPLATE_LAMBDA="xgboost-lambda-example"
export PREFIX_LAMBDA="sam_templates/xgboost-lambda-example"

and run

bash pipeline.sh -s <stage> -r -d ./xgboost-example

where <stage> refers to the development stage (i.e. dev, stage, prod). If you want to run each step at a time, refer to the Pytorch example for an explanation of each step.

Note. Refer to the xgboost-example/README.md file, to choose how to install xgboost, through miniconda or from source. While installing xgboost through conda is more easy, it is not recommended for a production setting as your lambda runtimes will be higher thus a higher billed duration time than installing it from source.

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2. Getting predictions

This example considers a trained XGBoost model with the Boston dataset.

The API endpoint expects to receive a list of 13 features according to the original dimensionality of the data. The handler will transform the input list to a numpy array.

For example,

curl -XPOST "here_goes_your_api_url" -H 'Content-Type: application/json' -d '{"input_X": [0.95577, 0, 8.14, 0, 0.538, 6.047, 88.8, 4.4534, 4, 307, 21, 306.38, 17.28]}'

where you can retrieve here_goes_your_api_url from the output of the lambda stack (template.yaml), see image below.

with the following output

{"message": "Succesful Prediction", "prediction": 14.716414451599121}

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References

AWS Lambda Runtime Interface Client. URL: https://github.com/aws/aws-lambda-python-runtime-interface-client

Creating Lambda Container Images. URL: https://docs.aws.amazon.com/lambda/latest/dg/images-create.html

Docker Commands Reference. URL: https://docs.docker.com/engine/reference/run/#entrypoint-default-command-to-execute-at-runtime

ECR Repository Resource. URL: https://docs.aws.amazon.com/es_es/AWSCloudFormation/latest/UserGuide/aws-resource-ecr-repository.html

News for AWS Lambda - Container Image Support. URL: https://aws.amazon.com/blogs/aws/new-for-aws-lambda-container-image-support/

Testing Lambda Container Images Locally. URL: https://docs.aws.amazon.com/lambda/latest/dg/images-test.html

Working with Lambda Layers and Extensions in Container Images. URL: https://aws.amazon.com/blogs/compute/working-with-lambda-layers-and-extensions-in-container-images/