hitter

hitter is a bot of slack, which can randomly select members and perform translations.

• Use the following icon for the bot
  • https://stampo.fun

Description

• Works as a slack bot
• It works by mentoring the bot and entering the default commands.
• Add a bot to the slack channel and use it
• May be subject to slack and AWS Lambda limitations

Features

The following five commands are currently available

1. hit
   • Randomly selected from the members of the channel
2. translate
   • Translate the text as you type it.
3. link
   • Generate a pre-signed URL to get access the attachments
4. short
   • Generate a shortened URL with expiration date
5. help
   • Displays help for the command

Requirement

• Go 1.15+

• Packages in use

  • aws / aws-lambda-go: ALibraries, samples and tools to help Go developers develop AWS Lambda functions.
    • https://github.com/aws/aws-lambda-go
  • slack-go / slack: Slack API in Go - community-maintained fork created by the original author, @nlopes
    • https://github.com/slack-go/slack
  • guregu / dynamo: expressive DynamoDB library for Go
    • https://github.com/guregu/dynamo
  • google / uuid: Go package for UUIDs based on RFC 4122 and DCE 1.1: Authentication and Security Services.
    • https://github.com/google/uuid
  • araddon / dateparse: GoLang Parse many date strings without knowing format in advance.
    • https://github.com/araddon/dateparse
  • kelseyhightower / envconfig: Golang library for managing configuration data from environment variables
    • https://github.com/kelseyhightower/envconfig

• Python 3.8+

• Node.js 14+

• aws / aws-cdk: The AWS Cloud Development Kit is a framework for defining cloud infrastructure in code

  • https://github.com/aws/aws-cdk

Usage

For details on how to use each command, see below

• hit

  • Synopsis
    • @hitter hit <number of selections> [<options> ...]
      • Please specify the number of people to select.
      • It is an error to specify how many people to select for a channel
      • It may take longer to run if there are too many participants in the channel
  • Options
    • --ex <@channel participant>
      • You can specify which members you want to exclude from the selection
      • Multiple options can be configured
      • Be sure to specify the format in which you want to mention
  • Examples
    • @hitter hit 2
      • I will select two participants from the channel
    • @hitter hit 3 --ex @userA --ex @userB
      • We will select three participants from the channel
      • There are options, so @userA and @userB are not available

• translate

  • Synopsis
    • @hitter translate <input text>
      • Input text is recognized even if it is on a new line
      • The language you entered is automatically determined
      • If there is a mixture of languages, it may not be determined correctly.
      • The upper limit of the input string depends on the maximum input value of slack
      • Whenever Japanese is entered, it will be translated into English.
      • If you enter a language other than Japanese, it will always be translated into Japanese.
  • Options
    • None
  • Examples
    • @hitter translate AWS is the world's most comprehensive and broadly adopted cloud platform
      • It's an English input, so it will be translated into Japanese
    • @hitter translate AWS は、世界で最も包括的で広く採用されているクラウドプラットフォームです
      • It's a Japanese input, so it will be translated into English

• link

  • Synopsis
    • @hitter link <expired minutes> <attachments>
      • Please specify the number of minutes of validity
      • Pre-Signed URLs will become invalid after the expiry minutes
      • Expiration minutes is dependent on AWS limitations
        • https://aws.amazon.com/premiumsupport/knowledge-center/presigned-url-s3-bucket-expiration/
        • AWS Security Token Service (STS): corresponds to a maximum of 36 hours of availability in this case
      • The default expiration minutes is set to 15 minutes
      • Multiple attachments are allowed.
      • Pre-Signed URLs are generated per attachment
      • The attachment size limit depends on the memory size of AWS Lambda
  • Options
    • None
  • Examples
    • @hitter link attachmentA
      • Generate a pre-signed URL for attachment A
    • @hitter link attachmentA attachmentB
      • Generates pre-signed URLs for attachment A and attachment B, respectively

• short

  • Synopsis
    • @hitter short <URL> <option>
      • Please specify the URL to be shortened
  • Options
    • --ttl <expiration date>
      • Shortened URLs will not be available after the expiration date
      • The default expiration date is set to 1 day
      • The number of days of validity depends on the TTL feature of Amazon DynamoDB
        • https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/howitworks-ttl.html
      • Depending on the timing of the deletion, the specified expiration date may be exceeded.
  • Examples
    • @hitter short https://www.example.com/
      • Generate a shortened URL for https://www.example.com/
    • @hitter short https://www.example.net/ --ttl 4
      • Generates a shortened URL of https://www.example.net/
      • expires in 4 days

• help

  • Synopsis
    • @hitter help
  • Options
    • None
  • Examples
    • @hitter help
      • Show brief help

Limitations

• About AWS Lambda

  • Dependent on memory capacity

    • Maximum file size of the attachment
    • Current setting is 2GB.
    • Maximum memory capacity of 3GB.
    • Files over the memory capacity will fail to be attached.
    • Architectural changes are required to break through this limitation
    • Consider using the Amazon Elastic File System (Amazon EFS)
    • https://docs.aws.amazon.com/lambda/latest/dg/services-efs.html

  • Dependent on execution time

    • Current setting is 15 minutes.
    • Maximum run time is 15 minutes.
    • If there are many members participating in the slack channel, the run time may be exceeded
    • If the attachment is large, the execution time may be exceeded.

• About Amazon DynamoDB

  • Depends on the capacity unit

    • Currently in On-Demand Mode
    • Note that it is automatically expanded, but the price is proportional

  • Depends on TTL specification

    • Item deletion is done through the TTL features.
    • This could be longer than the specified period depending on the TTL specification
    • https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/howitworks-ttl.html

• About AWS Resources

  • About the start of use

    • Basically, we use AWS CDK to build it
    • AWS CloudFormation is executed from CDK
    • However, the zone to be used as a domain must be created in advance
    • The zone name and zone ID will be required during the build process.

  • About deletion

    • Basically, the deletion is done by AWS CDK
    • AWS CloudFormation is executed from CDK
    • Zones for pre-created domains will not be deleted
    • Logs output to CloudWatch Logs will not be deleted
    • S3 cannot be deleted unless the bucket is empty, so it will not be deleted
    • All other resources will be deleted automatically.
    • If you need it, please make a backup in advance
    • To remove it completely, you will need to remove the above resources manually

Resources

• Amazon S3
  • https://aws.amazon.com/s3/
• Amazon API Gateway
  • https://aws.amazon.com/api-gateway/
• AWS Lambda
  • https://aws.amazon.com/lambda/
• Amazon Route 53
  • https://aws.amazon.com/route53/
• AWS Certificate Manager
  • https://aws.amazon.com/certificate-manager/
• Amazon DynamoDB
  • https://aws.amazon.com/dynamodb/
• Amazon CloudWatch Logs
  • https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/WhatIsCloudWatchLogs.html
• AWS CloudFormation
  • https://aws.amazon.com/cloudformation/
• AWS Identity and Access Management (IAM)
  • https://aws.amazon.com/iam/

Deployment

Get the sources yourself and do the build and deployment.

1. Getting the Source

$ git clone github.com/uchimanajet7/hitter

2. Building Lambda Functions

$ cd ./hitter/hitter/lambda
$ go get -v -t -d ./...
$ GOOS=linux go build -o main

$ cd ./hitter/hitter/lambda_api
$ go get -v -t -d ./...
$ GOOS=linux go build -o main

3. Deployment with AWS CDK

$ cd ./hitter/hitter
$ source .env/bin/activate
$ cdk synth
$ cdk deploy

You need to set the environment variables in order to deploy

You need to install the tools and set the environment variables in advance.

Setting Environment Variables in AWS CDK

$ export AWS_ACCESS_KEY_ID=<YOUR ACCESS KEY>
$ export AWS_SECRET_ACCESS_KEY=<YOUR SECRET KEY>
$ export AWS_DEFAULT_REGION=ap-northeast-1
$ export AWS_DEFAULT_OUTPUT=json

Setting Environment Variables in Amazon Route 53

$ export HITTER_ZONE_NAME=example.com
$ export HITTER_ZONE_ID=<YOUR ZONE ID>

Setting Environment Variables in Slack

$ export HITTER_SLACK_OAUTH_ACCESS_TOKEN=<YOUR SLACK OAUTH TOKEN>
$ export HITTER_SLACK_VERIFICATION_TOKEN=<YOUR SLACK VERIFICATION TOKEN>

If you don't have the time to set up the tools, you can use the Remote - Containers extension and Docker in Visual Studio Code to help you.

• Visual Studio Code
  • https://code.visualstudio.com
• Visual Studio Code Remote - Containers
  • https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers
• Developing inside a Container
  • https://code.visualstudio.com/docs/remote/containers
• Docker
  • https://www.docker.com

Author

uchimanajet7

Licence

Apache License 2.0

As reference information

• Create a Slack Bot for random selection using AWS CDK #aws #slack #cdk
  • https://medium.com/@uchimanajet7/create-a-slack-bot-for-random-selection-using-aws-cdk-aws-slack-cdk-e90b8a1c3536