index.ts

import express, { NextFunction, Request, Response } from 'express'
import multer from 'multer'
import path from 'path'
import cors from 'cors'
import http from 'http'
import * as fs from 'fs'
import basicAuth from 'express-basic-auth'
import { Server } from 'socket.io'
import logger from './utils/logger'
import { expressRequestLogger } from './utils/logger'

import {
    IChatFlow,
    IncomingInput,
    IReactFlowNode,
    IReactFlowObject,
    INodeData,
    IDatabaseExport,
    ICredentialReturnResponse
} from './Interface'
import {
    getNodeModulesPackagePath,
    getStartingNodes,
    buildLangchain,
    getEndingNode,
    constructGraphs,
    resolveVariables,
    isStartNodeDependOnInput,
    getAPIKeys,
    addAPIKey,
    updateAPIKey,
    deleteAPIKey,
    compareKeys,
    mapMimeTypeToInputField,
    findAvailableConfigs,
    isSameOverrideConfig,
    replaceAllAPIKeys,
    isFlowValidForStream,
    databaseEntities,
    getApiKey,
    transformToCredentialEntity,
    decryptCredentialData,
    clearSessionMemory,
    replaceInputsWithConfig,
    getEncryptionKey,
    checkMemorySessionId
} from './utils'
import { cloneDeep, omit } from 'lodash'
import { getDataSource } from './DataSource'
import { NodesPool } from './NodesPool'
import { ChatFlow } from './database/entities/ChatFlow'
import { ChatMessage } from './database/entities/ChatMessage'
import { Credential } from './database/entities/Credential'
import { Tool } from './database/entities/Tool'
import { ChatflowPool } from './ChatflowPool'
import { CachePool } from './CachePool'
import { ICommonObject, INodeOptionsValue } from 'flowise-components'
import { createRateLimiter, getRateLimiter, initializeRateLimiter } from './utils/rateLimit'

export class App {
    app: express.Application
    nodesPool: NodesPool
    chatflowPool: ChatflowPool
    cachePool: CachePool
    AppDataSource = getDataSource()

    constructor() {
        this.app = express()
    }

    async initDatabase() {
        // Initialize database
        this.AppDataSource.initialize()
            .then(async () => {
                logger.info('📦 [server]: Data Source has been initialized!')

                // Run Migrations Scripts
                await this.AppDataSource.runMigrations({ transaction: 'each' })

                // Initialize nodes pool
                this.nodesPool = new NodesPool()
                await this.nodesPool.initialize()

                // Initialize chatflow pool
                this.chatflowPool = new ChatflowPool()

                // Initialize API keys
                await getAPIKeys()

                // Initialize encryption key
                await getEncryptionKey()

                // Initialize Rate Limit
                const AllChatFlow: IChatFlow[] = await getAllChatFlow()
                await initializeRateLimiter(AllChatFlow)

                // Initialize cache pool
                this.cachePool = new CachePool()
            })
            .catch((err) => {
                logger.error('❌ [server]: Error during Data Source initialization:', err)
            })
    }

    async config(socketIO?: Server) {
        // Limit is needed to allow sending/receiving base64 encoded string
        this.app.use(express.json({ limit: '50mb' }))
        this.app.use(express.urlencoded({ limit: '50mb', extended: true }))

        if (process.env.NUMBER_OF_PROXIES && parseInt(process.env.NUMBER_OF_PROXIES) > 0)
            this.app.set('trust proxy', parseInt(process.env.NUMBER_OF_PROXIES))

        // Allow access from *
        this.app.use(cors())

        // Add the expressRequestLogger middleware to log all requests
        this.app.use(expressRequestLogger)

        if (process.env.FLOWISE_USERNAME && process.env.FLOWISE_PASSWORD) {
            const username = process.env.FLOWISE_USERNAME
            const password = process.env.FLOWISE_PASSWORD
            const basicAuthMiddleware = basicAuth({
                users: { [username]: password }
            })
            const whitelistURLs = [
                '/api/v1/verify/apikey/',
                '/api/v1/chatflows/apikey/',
                '/api/v1/public-chatflows',
                '/api/v1/prediction/',
                '/api/v1/node-icon/',
                '/api/v1/components-credentials-icon/',
                '/api/v1/chatflows-streaming',
                '/api/v1/ip'
            ]
            this.app.use((req, res, next) => {
                if (req.url.includes('/api/v1/')) {
                    whitelistURLs.some((url) => req.url.includes(url)) ? next() : basicAuthMiddleware(req, res, next)
                } else next()
            })
        }

        const upload = multer({ dest: `${path.join(__dirname, '..', 'uploads')}/` })

        // ----------------------------------------
        // Configure number of proxies in Host Environment
        // ----------------------------------------
        this.app.get('/api/v1/ip', (request, response) => {
            response.send({
                ip: request.ip,
                msg: 'See the returned IP address in the response. If it matches your current IP address ( which you can get by going to http://ip.nfriedly.com/ or https://api.ipify.org/ ), then the number of proxies is correct and the rate limiter should now work correctly. If not, increase the number of proxies by 1 until the IP address matches your own. Visit https://docs.flowiseai.com/deployment#rate-limit-setup-guide for more information.'
            })
        })

        // ----------------------------------------
        // Components
        // ----------------------------------------

        // Get all component nodes
        this.app.get('/api/v1/nodes', (req: Request, res: Response) => {
            const returnData = []
            for (const nodeName in this.nodesPool.componentNodes) {
                const clonedNode = cloneDeep(this.nodesPool.componentNodes[nodeName])
                returnData.push(clonedNode)
            }
            return res.json(returnData)
        })

        // Get all component credentials
        this.app.get('/api/v1/components-credentials', async (req: Request, res: Response) => {
            const returnData = []
            for (const credName in this.nodesPool.componentCredentials) {
                const clonedCred = cloneDeep(this.nodesPool.componentCredentials[credName])
                returnData.push(clonedCred)
            }
            return res.json(returnData)
        })

        // Get specific component node via name
        this.app.get('/api/v1/nodes/:name', (req: Request, res: Response) => {
            if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentNodes, req.params.name)) {
                return res.json(this.nodesPool.componentNodes[req.params.name])
            } else {
                throw new Error(`Node ${req.params.name} not found`)
            }
        })

        // Get component credential via name
        this.app.get('/api/v1/components-credentials/:name', (req: Request, res: Response) => {
            if (!req.params.name.includes('&')) {
                if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentCredentials, req.params.name)) {
                    return res.json(this.nodesPool.componentCredentials[req.params.name])
                } else {
                    throw new Error(`Credential ${req.params.name} not found`)
                }
            } else {
                const returnResponse = []
                for (const name of req.params.name.split('&')) {
                    if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentCredentials, name)) {
                        returnResponse.push(this.nodesPool.componentCredentials[name])
                    } else {
                        throw new Error(`Credential ${name} not found`)
                    }
                }
                return res.json(returnResponse)
            }
        })

        // Returns specific component node icon via name
        this.app.get('/api/v1/node-icon/:name', (req: Request, res: Response) => {
            if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentNodes, req.params.name)) {
                const nodeInstance = this.nodesPool.componentNodes[req.params.name]
                if (nodeInstance.icon === undefined) {
                    throw new Error(`Node ${req.params.name} icon not found`)
                }

                if (nodeInstance.icon.endsWith('.svg') || nodeInstance.icon.endsWith('.png') || nodeInstance.icon.endsWith('.jpg')) {
                    const filepath = nodeInstance.icon
                    res.sendFile(filepath)
                } else {
                    throw new Error(`Node ${req.params.name} icon is missing icon`)
                }
            } else {
                throw new Error(`Node ${req.params.name} not found`)
            }
        })

        // Returns specific component credential icon via name
        this.app.get('/api/v1/components-credentials-icon/:name', (req: Request, res: Response) => {
            if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentCredentials, req.params.name)) {
                const credInstance = this.nodesPool.componentCredentials[req.params.name]
                if (credInstance.icon === undefined) {
                    throw new Error(`Credential ${req.params.name} icon not found`)
                }

                if (credInstance.icon.endsWith('.svg') || credInstance.icon.endsWith('.png') || credInstance.icon.endsWith('.jpg')) {
                    const filepath = credInstance.icon
                    res.sendFile(filepath)
                } else {
                    throw new Error(`Credential ${req.params.name} icon is missing icon`)
                }
            } else {
                throw new Error(`Credential ${req.params.name} not found`)
            }
        })

        // load async options
        this.app.post('/api/v1/node-load-method/:name', async (req: Request, res: Response) => {
            const nodeData: INodeData = req.body
            if (Object.prototype.hasOwnProperty.call(this.nodesPool.componentNodes, req.params.name)) {
                try {
                    const nodeInstance = this.nodesPool.componentNodes[req.params.name]
                    const methodName = nodeData.loadMethod || ''

                    const returnOptions: INodeOptionsValue[] = await nodeInstance.loadMethods![methodName]!.call(nodeInstance, nodeData, {
                        appDataSource: this.AppDataSource,
                        databaseEntities: databaseEntities
                    })

                    return res.json(returnOptions)
                } catch (error) {
                    return res.json([])
                }
            } else {
                res.status(404).send(`Node ${req.params.name} not found`)
                return
            }
        })

        // ----------------------------------------
        // Chatflows
        // ----------------------------------------

        // Get all chatflows
        this.app.get('/api/v1/chatflows', async (req: Request, res: Response) => {
            const chatflows: IChatFlow[] = await getAllChatFlow()
            return res.json(chatflows)
        })

        // Get specific chatflow via api key
        this.app.get('/api/v1/chatflows/apikey/:apiKey', async (req: Request, res: Response) => {
            try {
                const apiKey = await getApiKey(req.params.apiKey)
                if (!apiKey) return res.status(401).send('Unauthorized')
                const chatflows = await this.AppDataSource.getRepository(ChatFlow)
                    .createQueryBuilder('cf')
                    .where('cf.apikeyid = :apikeyid', { apikeyid: apiKey.id })
                    .orWhere('cf.apikeyid IS NULL')
                    .orWhere('cf.apikeyid = ""')
                    .orderBy('cf.name', 'ASC')
                    .getMany()
                if (chatflows.length >= 1) return res.status(200).send(chatflows)
                return res.status(404).send('Chatflow not found')
            } catch (err: any) {
                return res.status(500).send(err?.message)
            }
        })

        // Get specific chatflow via id
        this.app.get('/api/v1/chatflows/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })
            if (chatflow) return res.json(chatflow)
            return res.status(404).send(`Chatflow ${req.params.id} not found`)
        })

        // Get specific chatflow via id (PUBLIC endpoint, used when sharing chatbot link)
        this.app.get('/api/v1/public-chatflows/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })
            if (chatflow && chatflow.isPublic) return res.json(chatflow)
            else if (chatflow && !chatflow.isPublic) return res.status(401).send(`Unauthorized`)
            return res.status(404).send(`Chatflow ${req.params.id} not found`)
        })

        // Save chatflow
        this.app.post('/api/v1/chatflows', async (req: Request, res: Response) => {
            const body = req.body
            const newChatFlow = new ChatFlow()
            Object.assign(newChatFlow, body)

            const chatflow = this.AppDataSource.getRepository(ChatFlow).create(newChatFlow)
            const results = await this.AppDataSource.getRepository(ChatFlow).save(chatflow)

            return res.json(results)
        })

        // Update chatflow
        this.app.put('/api/v1/chatflows/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })

            if (!chatflow) {
                res.status(404).send(`Chatflow ${req.params.id} not found`)
                return
            }

            const body = req.body
            const updateChatFlow = new ChatFlow()
            Object.assign(updateChatFlow, body)

            updateChatFlow.id = chatflow.id
            createRateLimiter(updateChatFlow)

            this.AppDataSource.getRepository(ChatFlow).merge(chatflow, updateChatFlow)
            const result = await this.AppDataSource.getRepository(ChatFlow).save(chatflow)

            // Update chatflowpool inSync to false, to build Langchain again because data has been changed
            this.chatflowPool.updateInSync(chatflow.id, false)

            return res.json(result)
        })

        // Delete chatflow via id
        this.app.delete('/api/v1/chatflows/:id', async (req: Request, res: Response) => {
            const results = await this.AppDataSource.getRepository(ChatFlow).delete({ id: req.params.id })
            return res.json(results)
        })

        // Check if chatflow valid for streaming
        this.app.get('/api/v1/chatflows-streaming/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })
            if (!chatflow) return res.status(404).send(`Chatflow ${req.params.id} not found`)

            /*** Get Ending Node with Directed Graph  ***/
            const flowData = chatflow.flowData
            const parsedFlowData: IReactFlowObject = JSON.parse(flowData)
            const nodes = parsedFlowData.nodes
            const edges = parsedFlowData.edges
            const { graph, nodeDependencies } = constructGraphs(nodes, edges)

            const endingNodeId = getEndingNode(nodeDependencies, graph)
            if (!endingNodeId) return res.status(500).send(`Ending node ${endingNodeId} not found`)

            const endingNodeData = nodes.find((nd) => nd.id === endingNodeId)?.data
            if (!endingNodeData) return res.status(500).send(`Ending node ${endingNodeId} data not found`)

            if (endingNodeData && endingNodeData.category !== 'Chains' && endingNodeData.category !== 'Agents') {
                return res.status(500).send(`Ending node must be either a Chain or Agent`)
            }

            const obj = {
                isStreaming: isFlowValidForStream(nodes, endingNodeData)
            }
            return res.json(obj)
        })

        // ----------------------------------------
        // ChatMessage
        // ----------------------------------------

        // Get all chatmessages from chatflowid
        this.app.get('/api/v1/chatmessage/:id', async (req: Request, res: Response) => {
            const chatmessages = await this.AppDataSource.getRepository(ChatMessage).find({
                where: {
                    chatflowid: req.params.id
                },
                order: {
                    createdDate: 'ASC'
                }
            })
            return res.json(chatmessages)
        })

        // Add chatmessages for chatflowid
        this.app.post('/api/v1/chatmessage/:id', async (req: Request, res: Response) => {
            const body = req.body
            const newChatMessage = new ChatMessage()
            Object.assign(newChatMessage, body)

            const chatmessage = this.AppDataSource.getRepository(ChatMessage).create(newChatMessage)
            const results = await this.AppDataSource.getRepository(ChatMessage).save(chatmessage)

            return res.json(results)
        })

        // Delete all chatmessages from chatflowid
        this.app.delete('/api/v1/chatmessage/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })
            if (!chatflow) {
                res.status(404).send(`Chatflow ${req.params.id} not found`)
                return
            }
            const flowData = chatflow.flowData
            const parsedFlowData: IReactFlowObject = JSON.parse(flowData)
            const nodes = parsedFlowData.nodes
            let chatId = await getChatId(chatflow.id)
            if (!chatId) chatId = chatflow.id
            clearSessionMemory(nodes, this.nodesPool.componentNodes, chatId, this.AppDataSource, req.query.sessionId as string)
            const results = await this.AppDataSource.getRepository(ChatMessage).delete({ chatflowid: req.params.id })
            return res.json(results)
        })

        // ----------------------------------------
        // Credentials
        // ----------------------------------------

        // Create new credential
        this.app.post('/api/v1/credentials', async (req: Request, res: Response) => {
            const body = req.body
            const newCredential = await transformToCredentialEntity(body)
            const credential = this.AppDataSource.getRepository(Credential).create(newCredential)
            const results = await this.AppDataSource.getRepository(Credential).save(credential)
            return res.json(results)
        })

        // Get all credentials
        this.app.get('/api/v1/credentials', async (req: Request, res: Response) => {
            if (req.query.credentialName) {
                let returnCredentials = []
                if (Array.isArray(req.query.credentialName)) {
                    for (let i = 0; i < req.query.credentialName.length; i += 1) {
                        const name = req.query.credentialName[i] as string
                        const credentials = await this.AppDataSource.getRepository(Credential).findBy({
                            credentialName: name
                        })
                        returnCredentials.push(...credentials)
                    }
                } else {
                    const credentials = await this.AppDataSource.getRepository(Credential).findBy({
                        credentialName: req.query.credentialName as string
                    })
                    returnCredentials = [...credentials]
                }
                return res.json(returnCredentials)
            } else {
                const credentials = await this.AppDataSource.getRepository(Credential).find()
                const returnCredentials = []
                for (const credential of credentials) {
                    returnCredentials.push(omit(credential, ['encryptedData']))
                }
                return res.json(returnCredentials)
            }
        })

        // Get specific credential
        this.app.get('/api/v1/credentials/:id', async (req: Request, res: Response) => {
            const credential = await this.AppDataSource.getRepository(Credential).findOneBy({
                id: req.params.id
            })

            if (!credential) return res.status(404).send(`Credential ${req.params.id} not found`)

            // Decrpyt credentialData
            const decryptedCredentialData = await decryptCredentialData(
                credential.encryptedData,
                credential.credentialName,
                this.nodesPool.componentCredentials
            )
            const returnCredential: ICredentialReturnResponse = {
                ...credential,
                plainDataObj: decryptedCredentialData
            }
            return res.json(omit(returnCredential, ['encryptedData']))
        })

        // Update credential
        this.app.put('/api/v1/credentials/:id', async (req: Request, res: Response) => {
            const credential = await this.AppDataSource.getRepository(Credential).findOneBy({
                id: req.params.id
            })

            if (!credential) return res.status(404).send(`Credential ${req.params.id} not found`)

            const body = req.body
            const updateCredential = await transformToCredentialEntity(body)
            this.AppDataSource.getRepository(Credential).merge(credential, updateCredential)
            const result = await this.AppDataSource.getRepository(Credential).save(credential)

            return res.json(result)
        })

        // Delete all chatmessages from chatflowid
        this.app.delete('/api/v1/credentials/:id', async (req: Request, res: Response) => {
            const results = await this.AppDataSource.getRepository(Credential).delete({ id: req.params.id })
            return res.json(results)
        })

        // ----------------------------------------
        // Tools
        // ----------------------------------------

        // Get all tools
        this.app.get('/api/v1/tools', async (req: Request, res: Response) => {
            const tools = await this.AppDataSource.getRepository(Tool).find()
            return res.json(tools)
        })

        // Get specific tool
        this.app.get('/api/v1/tools/:id', async (req: Request, res: Response) => {
            const tool = await this.AppDataSource.getRepository(Tool).findOneBy({
                id: req.params.id
            })
            return res.json(tool)
        })

        // Add tool
        this.app.post('/api/v1/tools', async (req: Request, res: Response) => {
            const body = req.body
            const newTool = new Tool()
            Object.assign(newTool, body)

            const tool = this.AppDataSource.getRepository(Tool).create(newTool)
            const results = await this.AppDataSource.getRepository(Tool).save(tool)

            return res.json(results)
        })

        // Update tool
        this.app.put('/api/v1/tools/:id', async (req: Request, res: Response) => {
            const tool = await this.AppDataSource.getRepository(Tool).findOneBy({
                id: req.params.id
            })

            if (!tool) {
                res.status(404).send(`Tool ${req.params.id} not found`)
                return
            }

            const body = req.body
            const updateTool = new Tool()
            Object.assign(updateTool, body)

            this.AppDataSource.getRepository(Tool).merge(tool, updateTool)
            const result = await this.AppDataSource.getRepository(Tool).save(tool)

            return res.json(result)
        })

        // Delete tool
        this.app.delete('/api/v1/tools/:id', async (req: Request, res: Response) => {
            const results = await this.AppDataSource.getRepository(Tool).delete({ id: req.params.id })
            return res.json(results)
        })

        // ----------------------------------------
        // Configuration
        // ----------------------------------------

        this.app.get('/api/v1/flow-config/:id', async (req: Request, res: Response) => {
            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: req.params.id
            })
            if (!chatflow) return res.status(404).send(`Chatflow ${req.params.id} not found`)
            const flowData = chatflow.flowData
            const parsedFlowData: IReactFlowObject = JSON.parse(flowData)
            const nodes = parsedFlowData.nodes
            const availableConfigs = findAvailableConfigs(nodes, this.nodesPool.componentCredentials)
            return res.json(availableConfigs)
        })

        this.app.post('/api/v1/node-config', async (req: Request, res: Response) => {
            const nodes = [{ data: req.body }] as IReactFlowNode[]
            const availableConfigs = findAvailableConfigs(nodes, this.nodesPool.componentCredentials)
            return res.json(availableConfigs)
        })

        this.app.get('/api/v1/version', async (req: Request, res: Response) => {
            const getPackageJsonPath = (): string => {
                const checkPaths = [
                    path.join(__dirname, '..', 'package.json'),
                    path.join(__dirname, '..', '..', 'package.json'),
                    path.join(__dirname, '..', '..', '..', 'package.json'),
                    path.join(__dirname, '..', '..', '..', '..', 'package.json'),
                    path.join(__dirname, '..', '..', '..', '..', '..', 'package.json')
                ]
                for (const checkPath of checkPaths) {
                    if (fs.existsSync(checkPath)) {
                        return checkPath
                    }
                }
                return ''
            }

            const packagejsonPath = getPackageJsonPath()
            if (!packagejsonPath) return res.status(404).send('Version not found')
            try {
                const content = await fs.promises.readFile(packagejsonPath, 'utf8')
                const parsedContent = JSON.parse(content)
                return res.json({ version: parsedContent.version })
            } catch (error) {
                return res.status(500).send(`Version not found: ${error}`)
            }
        })

        // ----------------------------------------
        // Export Load Chatflow & ChatMessage & Apikeys
        // ----------------------------------------

        this.app.get('/api/v1/database/export', async (req: Request, res: Response) => {
            const chatmessages = await this.AppDataSource.getRepository(ChatMessage).find()
            const chatflows = await this.AppDataSource.getRepository(ChatFlow).find()
            const apikeys = await getAPIKeys()
            const result: IDatabaseExport = {
                chatmessages,
                chatflows,
                apikeys
            }
            return res.json(result)
        })

        this.app.post('/api/v1/database/load', async (req: Request, res: Response) => {
            const databaseItems: IDatabaseExport = req.body

            await this.AppDataSource.getRepository(ChatFlow).delete({})
            await this.AppDataSource.getRepository(ChatMessage).delete({})

            let error = ''

            // Get a new query runner instance
            const queryRunner = this.AppDataSource.createQueryRunner()

            // Start a new transaction
            await queryRunner.startTransaction()

            try {
                const chatflows: ChatFlow[] = databaseItems.chatflows
                const chatmessages: ChatMessage[] = databaseItems.chatmessages

                await queryRunner.manager.insert(ChatFlow, chatflows)
                await queryRunner.manager.insert(ChatMessage, chatmessages)

                await queryRunner.commitTransaction()
            } catch (err: any) {
                error = err?.message ?? 'Error loading database'
                await queryRunner.rollbackTransaction()
            } finally {
                await queryRunner.release()
            }

            await replaceAllAPIKeys(databaseItems.apikeys)

            if (error) return res.status(500).send(error)
            return res.status(201).send('OK')
        })

        // ----------------------------------------
        // Prediction
        // ----------------------------------------

        // Send input message and get prediction result (External)
        this.app.post(
            '/api/v1/prediction/:id',
            upload.array('files'),
            (req: Request, res: Response, next: NextFunction) => getRateLimiter(req, res, next),
            async (req: Request, res: Response) => {
                await this.processPrediction(req, res, socketIO)
            }
        )

        // Send input message and get prediction result (Internal)
        this.app.post('/api/v1/internal-prediction/:id', async (req: Request, res: Response) => {
            await this.processPrediction(req, res, socketIO, true)
        })

        // ----------------------------------------
        // Marketplaces
        // ----------------------------------------

        // Get all chatflows for marketplaces
        this.app.get('/api/v1/marketplaces/chatflows', async (req: Request, res: Response) => {
            const marketplaceDir = path.join(__dirname, '..', 'marketplaces', 'chatflows')
            const jsonsInDir = fs.readdirSync(marketplaceDir).filter((file) => path.extname(file) === '.json')
            const templates: any[] = []
            jsonsInDir.forEach((file, index) => {
                const filePath = path.join(__dirname, '..', 'marketplaces', 'chatflows', file)
                const fileData = fs.readFileSync(filePath)
                const fileDataObj = JSON.parse(fileData.toString())
                const template = {
                    id: index,
                    name: file.split('.json')[0],
                    flowData: fileData.toString(),
                    description: fileDataObj?.description || ''
                }
                templates.push(template)
            })
            const FlowiseDocsQnA = templates.find((tmp) => tmp.name === 'Flowise Docs QnA')
            const FlowiseDocsQnAIndex = templates.findIndex((tmp) => tmp.name === 'Flowise Docs QnA')
            if (FlowiseDocsQnA && FlowiseDocsQnAIndex > 0) {
                templates.splice(FlowiseDocsQnAIndex, 1)
                templates.unshift(FlowiseDocsQnA)
            }
            return res.json(templates)
        })

        // Get all tools for marketplaces
        this.app.get('/api/v1/marketplaces/tools', async (req: Request, res: Response) => {
            const marketplaceDir = path.join(__dirname, '..', 'marketplaces', 'tools')
            const jsonsInDir = fs.readdirSync(marketplaceDir).filter((file) => path.extname(file) === '.json')
            const templates: any[] = []
            jsonsInDir.forEach((file, index) => {
                const filePath = path.join(__dirname, '..', 'marketplaces', 'tools', file)
                const fileData = fs.readFileSync(filePath)
                const fileDataObj = JSON.parse(fileData.toString())
                const template = {
                    ...fileDataObj,
                    id: index,
                    templateName: file.split('.json')[0]
                }
                templates.push(template)
            })
            return res.json(templates)
        })

        // ----------------------------------------
        // API Keys
        // ----------------------------------------

        // Get api keys
        this.app.get('/api/v1/apikey', async (req: Request, res: Response) => {
            const keys = await getAPIKeys()
            return res.json(keys)
        })

        // Add new api key
        this.app.post('/api/v1/apikey', async (req: Request, res: Response) => {
            const keys = await addAPIKey(req.body.keyName)
            return res.json(keys)
        })

        // Update api key
        this.app.put('/api/v1/apikey/:id', async (req: Request, res: Response) => {
            const keys = await updateAPIKey(req.params.id, req.body.keyName)
            return res.json(keys)
        })

        // Delete new api key
        this.app.delete('/api/v1/apikey/:id', async (req: Request, res: Response) => {
            const keys = await deleteAPIKey(req.params.id)
            return res.json(keys)
        })

        // Verify api key
        this.app.get('/api/v1/verify/apikey/:apiKey', async (req: Request, res: Response) => {
            try {
                const apiKey = await getApiKey(req.params.apiKey)
                if (!apiKey) return res.status(401).send('Unauthorized')
                return res.status(200).send('OK')
            } catch (err: any) {
                return res.status(500).send(err?.message)
            }
        })

        // ----------------------------------------
        // Serve UI static
        // ----------------------------------------

        const packagePath = getNodeModulesPackagePath('flowise-ui')
        const uiBuildPath = path.join(packagePath, 'build')
        const uiHtmlPath = path.join(packagePath, 'build', 'index.html')

        this.app.use('/', express.static(uiBuildPath))

        // All other requests not handled will return React app
        this.app.use((req, res) => {
            res.sendFile(uiHtmlPath)
        })
    }

    /**
     * Validate API Key
     * @param {Request} req
     * @param {Response} res
     * @param {ChatFlow} chatflow
     */
    async validateKey(req: Request, res: Response, chatflow: ChatFlow) {
        const chatFlowApiKeyId = chatflow.apikeyid
        const authorizationHeader = (req.headers['Authorization'] as string) ?? (req.headers['authorization'] as string) ?? ''

        if (chatFlowApiKeyId && !authorizationHeader) return res.status(401).send(`Unauthorized`)

        const suppliedKey = authorizationHeader.split(`Bearer `).pop()
        if (chatFlowApiKeyId && suppliedKey) {
            const keys = await getAPIKeys()
            const apiSecret = keys.find((key) => key.id === chatFlowApiKeyId)?.apiSecret
            if (!compareKeys(apiSecret, suppliedKey)) return res.status(401).send(`Unauthorized`)
        }
    }

    /**
     * Process Prediction
     * @param {Request} req
     * @param {Response} res
     * @param {Server} socketIO
     * @param {boolean} isInternal
     */
    async processPrediction(req: Request, res: Response, socketIO?: Server, isInternal = false) {
        try {
            const chatflowid = req.params.id
            let incomingInput: IncomingInput = req.body

            let nodeToExecuteData: INodeData

            const chatflow = await this.AppDataSource.getRepository(ChatFlow).findOneBy({
                id: chatflowid
            })
            if (!chatflow) return res.status(404).send(`Chatflow ${chatflowid} not found`)

            let chatId = await getChatId(chatflow.id)
            if (!chatId) chatId = chatflowid

            if (!isInternal) {
                await this.validateKey(req, res, chatflow)
            }

            let isStreamValid = false

            const files = (req.files as any[]) || []

            if (files.length) {
                const overrideConfig: ICommonObject = { ...req.body }
                for (const file of files) {
                    const fileData = fs.readFileSync(file.path, { encoding: 'base64' })
                    const dataBase64String = `data:${file.mimetype};base64,${fileData},filename:${file.filename}`

                    const fileInputField = mapMimeTypeToInputField(file.mimetype)
                    if (overrideConfig[fileInputField]) {
                        overrideConfig[fileInputField] = JSON.stringify([...JSON.parse(overrideConfig[fileInputField]), dataBase64String])
                    } else {
                        overrideConfig[fileInputField] = JSON.stringify([dataBase64String])
                    }
                }
                incomingInput = {
                    question: req.body.question ?? 'hello',
                    overrideConfig,
                    history: [],
                    socketIOClientId: req.body.socketIOClientId
                }
            }

            /*** Get chatflows and prepare data  ***/
            const flowData = chatflow.flowData
            const parsedFlowData: IReactFlowObject = JSON.parse(flowData)
            const nodes = parsedFlowData.nodes
            const edges = parsedFlowData.edges

            /*   Reuse the flow without having to rebuild (to avoid duplicated upsert, recomputation) when all these conditions met:
             * - Node Data already exists in pool
             * - Still in sync (i.e the flow has not been modified since)
             * - Existing overrideConfig and new overrideConfig are the same
             * - Flow doesn't start with/contain nodes that depend on incomingInput.question
             ***/
            const isFlowReusable = () => {
                return (
                    Object.prototype.hasOwnProperty.call(this.chatflowPool.activeChatflows, chatflowid) &&
                    this.chatflowPool.activeChatflows[chatflowid].inSync &&
                    isSameOverrideConfig(
                        isInternal,
                        this.chatflowPool.activeChatflows[chatflowid].overrideConfig,
                        incomingInput.overrideConfig
                    ) &&
                    !isStartNodeDependOnInput(this.chatflowPool.activeChatflows[chatflowid].startingNodes, nodes)
                )
            }

            if (isFlowReusable()) {
                nodeToExecuteData = this.chatflowPool.activeChatflows[chatflowid].endingNodeData
                isStreamValid = isFlowValidForStream(nodes, nodeToExecuteData)
                logger.debug(
                    `[server]: Reuse existing chatflow ${chatflowid} with ending node ${nodeToExecuteData.label} (${nodeToExecuteData.id})`
                )
            } else {
                /*** Get Ending Node with Directed Graph  ***/
                const { graph, nodeDependencies } = constructGraphs(nodes, edges)
                const directedGraph = graph
                const endingNodeId = getEndingNode(nodeDependencies, directedGraph)
                if (!endingNodeId) return res.status(500).send(`Ending node ${endingNodeId} not found`)

                const endingNodeData = nodes.find((nd) => nd.id === endingNodeId)?.data
                if (!endingNodeData) return res.status(500).send(`Ending node ${endingNodeId} data not found`)

                if (endingNodeData && endingNodeData.category !== 'Chains' && endingNodeData.category !== 'Agents') {
                    return res.status(500).send(`Ending node must be either a Chain or Agent`)
                }

                if (
                    endingNodeData.outputs &&
                    Object.keys(endingNodeData.outputs).length &&
                    !Object.values(endingNodeData.outputs).includes(endingNodeData.name)
                ) {
                    return res
                        .status(500)
                        .send(
                            `Output of ${endingNodeData.label} (${endingNodeData.id}) must be ${endingNodeData.label}, can't be an Output Prediction`
                        )
                }

                isStreamValid = isFlowValidForStream(nodes, endingNodeData)

                /*** Get Starting Nodes with Non-Directed Graph ***/
                const constructedObj = constructGraphs(nodes, edges, true)
                const nonDirectedGraph = constructedObj.graph
                const { startingNodeIds, depthQueue } = getStartingNodes(nonDirectedGraph, endingNodeId)

                logger.debug(`[server]: Start building chatflow ${chatflowid}`)
                /*** BFS to traverse from Starting Nodes to Ending Node ***/
                const reactFlowNodes = await buildLangchain(
                    startingNodeIds,
                    nodes,
                    graph,
                    depthQueue,
                    this.nodesPool.componentNodes,
                    incomingInput.question,
                    incomingInput.history,
                    chatId,
                    chatflowid,
                    this.AppDataSource,
                    incomingInput?.overrideConfig,
                    this.cachePool
                )

                const nodeToExecute = reactFlowNodes.find((node: IReactFlowNode) => node.id === endingNodeId)
                if (!nodeToExecute) return res.status(404).send(`Node ${endingNodeId} not found`)

                if (incomingInput.overrideConfig)
                    nodeToExecute.data = replaceInputsWithConfig(nodeToExecute.data, incomingInput.overrideConfig)
                const reactFlowNodeData: INodeData = resolveVariables(
                    nodeToExecute.data,
                    reactFlowNodes,
                    incomingInput.question,
                    incomingInput.history
                )
                nodeToExecuteData = reactFlowNodeData

                const startingNodes = nodes.filter((nd) => startingNodeIds.includes(nd.id))
                this.chatflowPool.add(chatflowid, nodeToExecuteData, startingNodes, incomingInput?.overrideConfig)
            }

            const nodeInstanceFilePath = this.nodesPool.componentNodes[nodeToExecuteData.name].filePath as string
            const nodeModule = await import(nodeInstanceFilePath)
            const nodeInstance = new nodeModule.nodeClass()

            logger.debug(`[server]: Running ${nodeToExecuteData.label} (${nodeToExecuteData.id})`)

            if (nodeToExecuteData.instance) checkMemorySessionId(nodeToExecuteData.instance, chatId)

            const result = isStreamValid
                ? await nodeInstance.run(nodeToExecuteData, incomingInput.question, {
                      chatHistory: incomingInput.history,
                      socketIO,
                      socketIOClientId: incomingInput.socketIOClientId,
                      logger,
                      appDataSource: this.AppDataSource,
                      databaseEntities,
                      analytic: chatflow.analytic
                  })
                : await nodeInstance.run(nodeToExecuteData, incomingInput.question, {
                      chatHistory: incomingInput.history,
                      logger,
                      appDataSource: this.AppDataSource,
                      databaseEntities,
                      analytic: chatflow.analytic
                  })

            logger.debug(`[server]: Finished running ${nodeToExecuteData.label} (${nodeToExecuteData.id})`)
            return res.json(result)
        } catch (e: any) {
            logger.error('[server]: Error:', e)
            return res.status(500).send(e.message)
        }
    }

    async stopApp() {
        try {
            const removePromises: any[] = []
            await Promise.all(removePromises)
        } catch (e) {
            logger.error(`❌[server]: Flowise Server shut down error: ${e}`)
        }
    }
}

/**
 * Get first chat message id
 * @param {string} chatflowid
 * @returns {string}
 */
export async function getChatId(chatflowid: string) {
    // first chatmessage id as the unique chat id
    const firstChatMessage = await getDataSource()
        .getRepository(ChatMessage)
        .createQueryBuilder('cm')
        .select('cm.id')
        .where('chatflowid = :chatflowid', { chatflowid })
        .orderBy('cm.createdDate', 'ASC')
        .getOne()
    return firstChatMessage ? firstChatMessage.id : ''
}

let serverApp: App | undefined

export async function getAllChatFlow(): Promise<IChatFlow[]> {
    return await getDataSource().getRepository(ChatFlow).find()
}

export async function start(): Promise<void> {
    serverApp = new App()

    const port = parseInt(process.env.PORT || '', 10) || 3000
    const server = http.createServer(serverApp.app)

    const io = new Server(server, {
        cors: {
            origin: '*'
        }
    })

    await serverApp.initDatabase()
    await serverApp.config(io)

    server.listen(port, () => {
        logger.info(`⚡️ [server]: Flowise Server is listening at ${port}`)
    })
}

export function getInstance(): App | undefined {
    return serverApp
}