KMB ETA API

A serverless funtion appied the headerless browser running in AWS lambda to fetch the KMB Bus ETA API data.

Blog posts

• https://www.adamliu.net/how-to-use-the-headerless-browser-to-fetch-the-hk-kmb-eta-data-fight-with-the-recaptcha
• https://www.adamliu.net/say-byebye-to-the-eta-features-in-my-wechat-miniprogram

Run locally

npm install -g serverless
# cd to the floder
npm i
sls offline
# open this link in browser http://localhost:3000/?route=280X&bound=2&seq=3&bsicode=NA06-N-1800-0

Deploy on AWS Lambda

Prepare the lambda layer

The puppeteer is too big, the size is more that 262144000 bytes(lambda unzipped size limit). puppeteer-core is recommended to lambda.

1. Follow the link section to add the lambda layer https://github.com/alixaxel/chrome-aws-lambda#aws-lambda-layer
2. It will get the ARN if added successfully.
3. Update serverless.yml layers key.
4. Remember to remove node_modules and rerun npm install if package.json changes.

CLI

sls deploy
# 1. change the serverless to specify aws profile
# 2. if deploy successfully, you will get  a link from AWS API Gateway
# 3. call the link in browser to test the lambda https://xxx.amazonaws.com/dev/?route=280X&bound=2&seq=3&bsicode=NA06-N-1800-0

REF

1. Lambda IP ranges https://docs.aws.amazon.com/general/latest/gr/aws-ip-ranges.html