病院のベッドを検索するWhatsAppとMessengerのGraphQLボットを構築する

// package.json

{
  "scripts": {
    "dev": "nodemon src/app.js"
  }
}

// src/app.js

const express = require("express")

const app = express()
app.use(express.json())

// src/app.js

const { fixedMessages, sendMessage } = require("./utils")

app.post("/webhooks/inbound", (request, response) => {
  console.log(request.body)
)

app.post("/webhooks/status", (request, response) => {
  console.log(request.body)
  response.status(200).end()
})

app.listen(3000, () => {
  console.log("Listening on port 3000")
})

VONAGE_API_KEY = // Your Vonage API key
VONAGE_API_SECRET = // Your Vonage API Secret
WHATSAPP_NUMBER = // The from number in the case of the WhatsApp Sandbox
MESSENGER_ID = // The from ID of the Messenger Sandbox

// src/app.js
require("dotenv").config()

// src/utils.js

const axios = require("axios")

// default message type will be `text`
const sendMessage = async (to, message, type = "text") => {  let from = {
    // either 'WhatsApp' or 'messenger'
    type: to.type,
  }

  if (to.type === "whatsapp") {
    // the WhatsApp Sandbox number    
    from.number = proccess.env.WHATSAPP_NUMBER
  } else if (to.type === "messenger") {
    // the Messenger Sandbox ID
    from.id = process.env.MESSENGER_ID
  }

  await axios.post(
    "https://messages-sandbox.nexmo.com/v0.1/messages",
    {
      to,
      from,
      message: {
        content: {
          type,
          [type]: message,
        },
      },
    },
    {
      auth: {
        username: process.env.VONAGE_API_KEY,
        password: process.env.VONAGE_API_SECRET,
      },
    }
  )
}

module.exports = {
  sendMessage,
}

// src/app.js

const handleInbound = async (request, response) => {
  const content = request.body.message.content

  const text = content.text.toLowerCase().trim()

  // whom we have to reply to
  const to = request.body.from

  const searchRegex = /^search .* in .*$/i
  const directionsRegex = /^get directions to .*/i

  if (text.match(searchRegex)) {
    handleSearch(text, to)
  } else if (text.match(directionsRegex)) {
    handleDirections(text, to)
  } else if (["help", "hi", "hello"].includes(text)) {
    sendMessage(to, fixedMessages.help)
  } else if (text === "cities") {
    sendMessage(to, fixedMessages.cities)
  } else {
    sendMessage(to, `Sorry, invalid message. Type *help* to get a list of all commands.`)
  }

  response.status(200).end()
}

// src/app.js
app.post("/webhooks/inbound", handleInbound)

// src/utils.js

const outdent = require("outdent")

const fixedMessages = {
  help: outdent`
    The Bedav Bot gives you information on the availability of beds in hospitals and the contact information and location of those hospitals as well.
    
    You can use the following commands:
    1. *help* - Get this menu and all the commands you can use
    2. *cities* - Get a list of all the cities available
    2. *search* _<hospital-name>_ *in* _<location>_ - Search for a hospital in a particular location. For example, "search sakra in bangalore" searches for hospitals with the name Sakra in Bangalore
    3. *get directions to* _<hospital-id>_ - Get directions to a hospital with a particular ID. You can get the hospital ID from the search results. The serial number preceding the Hospital name is the Hospital ID. For example, if the search result has _(87) Sakra Hospital_, send _get directions to 87_ to get directions to Sakra Hospital.
  `,
  cities: outdent`
    The cities/districts currently available are:

    *Karnataka*
      1. Bangalore/Bengaluru

    *Maharashtra*
      2. Pune
      3. Kohlapur
      4. Sangli
      5. Satara
      6. Solapur

    *Andhra Pradesh*
      7. Anantapur
      8. Chittoor
      9. East Godavari
      10. Guntur
      11. Krishna
      12. Kurnool
      13. Prakasam
      14. Nellore
      15. Srikakulam
      16. Vishakapatanam
      17. Vizianagaram
      18. West Godavari
      19. Kadapa
  `,
}

module.exports = {
  ...
  fixedMessages,
}

// app.js

const { GraphQLClient } = require("graphql-request")
const client = new GraphQLClient("https://bedav.org/graphql")

// src/utils.js

const { encode, decode } = require("js-base64")

const getHospitalId = (encodedId) => {
  return decode(encodedId).slice(9)
}

const getEncodedString = (hospitalId) => {
  return encode(`Hospital:${hospitalId}`)
}

module.exports = {
  ...
  getEncodedString,
}

// src/utils.js

const getFormattedHospital = (hospital) => {
  const index = getHospitalId(hospital.id)

  const roundedString = (occupied, total) => {
    return `${Math.floor((occupied * 100) / total)}% Occupied`
  }

  const h = hospital

  // Percentages of beds available
  const percentages = {
    icu: roundedString(h.icuOccupied, h.icuTotal),
    hdu: roundedString(h.hduOccupied, h.icuTotal),
    oxygen: roundedString(h.oxygenOccupied, h.icuTotal),
    general: roundedString(h.generalOccupied, h.icuTotal),
    ventilators: roundedString(h.ventilatorsOccupied, h.icuTotal),
  }

  const formatted = outdent`
    *(${index}) ${hospital.name}*
      ${h.icuTotal !== 0 && h.icuAvailable !== null ? `_ICU Available_: ${h.icuAvailable} (${percentages.icu})` : ""}
      ${h.hduTotal !== 0 && h.icuAvailable !== null ? `_HDU Avalable_: ${h.hduAvailable} (${percentages.hdu})` : ""}
      ${h.oxygenTotal !== 0 && h.oxygenAvailable !== null ? `_Oxygen Available_: ${h.oxygenAvailable} (${percentages.oxygen}})` : ""}
      ${h.generalTotal !== 0 && h.generalAvailable !== null ? `_General Available_: ${h.generalAvailable} (${percentages.general})` : ""}
      ${
        h.ventilatorsTotal !== 0 && h.ventilatorsAvailable !== null
          ? `_Ventilators Available_: ${h.ventilatorsAvailable} (${percentages.ventilators})`
          : ""
      }
      ${h.phone !== null ? `_Phone_: ${h.phone}` : ""}
      ${h.phone !== null ? `_Website_: ${h.website}` : ""}
  `

  return removeEmptyLines(formatted)
}

// src/utils.js

const removeEmptyLines = (string) => {
  const lines = string.split("\n")
  const newLines = []

  for (const line of lines) {
    // Continue if the line is a blank line
    if (line.match(/^\s*$/)) continue
    newLines.push(line)
  }

  return newLines.join("\n")
}

// src/utils.js

const getFormattedHospitals = (hospitals) => {
  let message = ""

  for (const hospital of hospitals) {
    const formattedHospital = getFormattedHospital(hospital)
    message += formattedHospital + "\n\n"
  }

  return message
}

module.exports = {
  ...
  getFormattedHospitals,
}

// src/queries.js

const searchGraphQLQuery = gql`
  query($location: String, $query: String) {
    # get hospitals from a city named Bengaluru in the state of Karnataka
    locality(name: $location) {
      hospitals(first: 5, searchQuery: $query) {
        edges {
          node {
            id
            name
            phone
            website
            address
            latitude
            longitude

            icuAvailable
            hduAvailable
            oxygenAvailable
            generalAvailable
            ventilatorsAvailable

            icuOccupied
            hduOccupied
            oxygenOccupied
            generalOccupied
            ventilatorsOccupied

            icuTotal
            hduTotal
            oxygenTotal
            generalTotal
            ventilatorsTotal
          }
        }
      }
    }
  }
`

module.exports = {
  searchGraphQLQuery,
}
`

// src/utils.js

const locationKey = {
  bangalore: "bengaluru-karnataka",
  bengaluru: "bengaluru-karnataka",
  pune: "pune-maharashtra",
  kohlapur: "kohlapur-maharashtra",
  sangli: "sangli-maharashtra",
  satara: "satara-maharashtra",
  solapur: "solapur-maharashtra",
  anantapur: "anantapur-andhra pradesh",
  chittoor: "chittoor-andhra pradesh",
  "east godavari": "east godavari-andhra pradesh",
  guntur: "guntur-andhra pradesh",
  krishna: "krishna-andhra pradesh",
  kurnool: "kurnool-andhra pradesh",
  prakasam: "prakasam-andhra pradesh",
  nellore: "spsr nellore-andhra pradesh",
  srikakulam: "srikakulam-andhra pradesh",
  vishakapatanam: "vishakapatanam-andhra pradesh",
  vizianagaram: "vizianagaram-andhra pradesh",
  "west godavari": "west godavari-andhra pradesh",
  kadapa: "kadapa-andhra pradesh",
}

module.exports = {
  ...
  locationKey,
}

// src/app.js

const { fixedMessages, sendMessage, locationKey, getFormattedHospitals } = require("./utils")

const handleSearch = async (message, to) => {
  // extract the search query and location from the message
  const searchRegex = /^search (?<searchQuery>[a-zA-Z0-9_ ]+) in (?<location>[a-zA-Z0-9_ ]+)$/i
  const match = searchRegex.exec(message)

  if (match === null) {
    sendMessage(to, "Please enter the hospital name you want to search for and the location")
    return
  }

  const { groups: { searchQuery, location } } = match

  if (!Object.keys(locationKey).includes(location)) {
    sendMessage(to, "Invalid location entered. Type *cities* to look at all the cities available")
    return
  }

  try {
    const data = await client.request(searchGraphQLQuery, {
      location: locationKey[location],
      query: searchQuery,
    })

   const { edges } = data.locality.hospitals
    const hospitals = edges.map((item) => item.node)

    if (edges.length === 0) {
      sendMessage(to, "Sorry, there were no hospitals that matched your search 🙁")
      return
    }

    const formattedMessage = getFormattedHospitals(hospitals)
    sendMessage(to, formattedMessage)
  } catch (error) {
    sendMessage(to, "Sorry, there were no hospitals that matched your search 🙁")
  }
}

// src/queries.js

const directionsGraphQLQuery = gql`
  query($id: ID!) {
    hospital(id: $id) {
      id
      longitude
      latitude
      name
      address
    }
  }
`

module.exports = {
  ...
  directionsGraphQLQuery,
}

// src/app.js

const handleDirections = async (message, to) => {
  const directionsRegex = /^get directions to (?<hospitalId>\d+)$/i
  const match = directionsRegex.exec(message)

  if (match === null) {
    sendMessage(to, "Please enter a valid Hospital ID")
    return
  }

  const hospitalId = getEncodedString(parseInt(match.groups.hospitalId))

  try {
    const { hospital } = await client.request(directionsGraphQLQuery, {
      id: hospitalId,
    })

    if (to.type === "whatsapp") {
      sendMessage(
        to,
        {
          type: "location",
          location: {
            longitude: hospital.longitude,
            latitude: hospital.latitude,
            name: hospital.name,
            address: hospital.address,
          },
        },
        "custom"
      )
    } else {
      const link = `https://maps.google.com/maps?q=${hospital.latitude},${hospital.longitude}`
      const message = `${link}\n*${hospital.name}*\n${hospital.address}\n`

      sendMessage(to, message)
    }
  } catch (error) {
    sendMessage(to, "Please enter a valid Hospital ID")
  }
}