Backend: invoice upload

backend/package.json

@@ -20,6 +20,7 @@
     "dotenv": "^7.0.0",
     "express": "^4.16.4",
     "graphql": "^14.1.1",
+    "html-pdf": "^2.2.0",
     "indicative": "^5.0.8",
     "jsonwebtoken": "^8.5.1",
     "mongoose": "^5.4.19"

backend/src/constants.js

@@ -0,0 +1,18 @@
+exports.TR_FLOW = {
+  IN: 'IN',
+  OUT: 'OUT'
+};
+
+exports.TR_TYPE = {
+  INVOICE: 'INVOICE',
+  EXPENSE: 'EXPENSE'
+};
+
+exports.STORAGE_PATH = {
+  INVOICE_PENDING: '/invoices/pending',
+  INVOICE_PAID: '/invoices/paid',
+  INVOICE_REJECTED: '/invoices/rejected',
+  EXPENSE_PENDING: '/expenses/pending',
+  EXPENSE_PAID: '/expenses/paid',
+  EXPENSE_REJECTED: '/expenses/rejected'
+};

backend/src/db.js

@@ -12,6 +12,8 @@ module.exports.connect = async () => {
       await mongoose.connection.createCollection('users');
       await mongoose.connection.createCollection('transactions');
       await mongoose.connection.createCollection('categories');
+      await mongoose.connection.createCollection('companies');
+      await mongoose.connection.createCollection('counters');
       console.log('Collections created successfully!');
     })
     .catch(err => {

backend/src/graphql/resolvers/mutations.js

@@ -1,23 +1,45 @@
-const {
-  validate,
-  registerValidation,
-  updateProfileValidation,
-  expenseValidation
-} = require('../../lib/validation');
-
-const store = (file, tags, folder, cloudinary) =>
+const saveOrRetrieveCompany = async (company, Company, upsert) => {
+  if (!company) return null;
+  const { name, id } = company;
+  if (!name && !id) return null;
+  if (company.id) {
+    return Company.findById(id);
+  }
+  if (company) {
+    return Company.findOneAndUpdate({ name }, company, { new: true, upsert });
+  }
+  return null;
+};
+
+const getInvoiceRef = async (id, Counter) => {
+  const counter = await Counter.findByIdAndUpdate(
+    id,
+    { $inc: { sequence: 1 } },
+    { new: true, upsert: true }
+  );
+  const INVOICE_REF_SIZE = process.env.INVOICE_REF_SIZE || 4;
+  const z = '0';
+  return `${id}/${`${z.repeat(INVOICE_REF_SIZE)}${counter.sequence}`.slice(-INVOICE_REF_SIZE)}`;
+};
+
+const store = (file, tags, folder, cloudinary, generated) =>
   new Promise((resolve, reject) => {
     const uploadStream = cloudinary.uploader.upload_stream({ tags, folder }, (err, image) => {
       if (image) {
         return resolve(image);
       }
       return reject(err);
     });
-    file.createReadStream().pipe(uploadStream);
+    if (!generated) file.createReadStream().pipe(uploadStream);
+    else file.pipe(uploadStream);
   });
 
 module.exports = {
-  register: async (_, { user }, { models: { User } }) => {
+  register: async (
+    _,
+    { user },
+    { models: { User }, validation: { registerValidation, validate } }
+  ) => {
     const { formatData, rules, messages } = registerValidation;
     await validate(formatData({ ...user }), rules, messages);
 
@@ -32,23 +54,35 @@ module.exports = {
   expenseClaim: async (
     unused,
     { expense },
-    { user, models: { Transaction, User }, cloudinary, db }
+    {
+      user,
+      models: { Transaction, User },
+      cloudinary,
+      db,
+      constants: { TR_TYPE, TR_FLOW, STORAGE_PATH },
+      validation: { expenseValidation, validate }
+    }
   ) => {
     expense.date = expense.date || Date.now();
 
     const { formatData, rules, messages } = expenseValidation;
     await validate(formatData({ ...expense }), rules, messages);
 
     expense.user = user.id;
-    expense.flow = 'IN';
-    expense.type = 'EXPENSE';
+    expense.flow = TR_FLOW.IN;
+    expense.type = TR_TYPE.EXPENSE;
     const receipt = await expense.receipt;
 
     const session = await db.startSession();
     let tr;
     try {
       // upload the file to cloudinary
-      const file = await store(receipt, 'expense receipt', '/expenses/pending/', cloudinary);
+      const file = await store(
+        receipt,
+        'expense receipt',
+        STORAGE_PATH.EXPENSE_PENDING,
+        cloudinary
+      );
       expense.file = file.secure_url;
 
       const opts = { session };
@@ -76,7 +110,11 @@ module.exports = {
     }
     return tr;
   },
-  updateProfile: async (_, args, { user, models: { User } }) => {
+  updateProfile: async (
+    _,
+    args,
+    { user, models: { User }, validation: { updateProfileValidation, validate } }
+  ) => {
     const { formatData, rules, messages } = updateProfileValidation;
     await validate(formatData({ ...args.user }), rules, messages);
     const { email } = args.user;
@@ -87,15 +125,81 @@ module.exports = {
       }
     }
     return User.findOneAndUpdate({ _id: user.id }, args.user, { new: true });
+  },
+  uploadInvoice: async (
+    root,
+    { invoice },
+    {
+      models: { Transaction, Company, Category },
+      cloudinary,
+      constants: { TR_TYPE, TR_FLOW, STORAGE_PATH },
+      validation: { uploadInvoiceValidation, validate }
+    }
+  ) => {
+    const { formatData, rules, messages } = uploadInvoiceValidation;
+    await validate(formatData({ ...invoice }), rules, messages);
+
+    // look for a company (by id or name), if name is provided: update it or save it if doesn't exist
+    const company = await saveOrRetrieveCompany(invoice.company, Company, true);
+    invoice.company = company;
+    if (invoice.category && (invoice.category.name || invoice.category.id)) {
+      const category = Category.findOne({
+        $or: [{ _id: company.category.id }, { name: company.category.id }]
+      });
+      if (!category) {
+        throw new Error('Category not found.');
+      }
+      invoice.category = category;
+    }
+    invoice.flow = TR_FLOW.IN;
+    invoice.type = TR_TYPE.INVOICE;
+    invoice.date = invoice.date || Date.now();
+    invoice.invoice = await invoice.invoice;
+
+    const file = await store(invoice.invoice, 'invoice', STORAGE_PATH.INVOICE_PENDING, cloudinary);
+    invoice.file = file.secure_url;
+
+    return new Transaction(invoice).save();
+  },
+  generateInvoice: async (
+    root,
+    { invoice },
+    {
+      models: { Transaction, Company, Counter },
+      cloudinary,
+      constants: { TR_TYPE, TR_FLOW, STORAGE_PATH },
+      validation: { generateInvoiceValidation, validate },
+      generateInvoicePDF
+    }
+  ) => {
+    const { formatData, rules, messages } = generateInvoiceValidation;
+
+    // look for a company (by id or name), if name is provided: update it or save it if doesn't exist
+    const company = await saveOrRetrieveCompany(invoice.company, Company, true);
+    invoice.company = company;
+
+    //  validate the inputs with the retrieved company, will throw if any required element is missing
+    await validate(formatData(invoice), rules, messages);
+    invoice.type = TR_TYPE.INVOICE;
+    invoice.flow = TR_FLOW.OUT;
+    invoice.date = Date.now();
+
+    const noInvoice = await getInvoiceRef(new Date(invoice.date).getFullYear(), Counter);
+    invoice.ref = noInvoice;
+
+    let file = await generateInvoicePDF(
+      invoice.details,
+      {
+        date: invoice.date,
+        VAT: invoice.VAT,
+        noInvoice
+      },
+      invoice.company
+    );
+
+    file = await store(file, 'invoice', STORAGE_PATH.INVOICE_PENDING, cloudinary, true);
+    invoice.file = file.secure_url;
+
+    return new Transaction(invoice).save();
   }
 };
-
-// TODO REMOVE EXAMPLE
-// {
-//   "query": "mutation ($amount: Float!, $description: String!, $receipt: Upload!) {expenseClaim(expense: {amount: $amount, description: $description, receipt: $receipt}) {id}}",
-//   "variables": {
-//     "amount": 10,
-//     "description": "Hello World!",
-//     "receipt": null
-//   }
-// }

backend/src/graphql/types.js

@@ -18,6 +18,8 @@ module.exports = gql`
     login(email: String!, password: String!): User! @guest
     expenseClaim(expense: Expense!): Transaction! @auth
     updateProfile(user: UserUpdateInput!): User! @auth
+    uploadInvoice(invoice: InvoiceUpload!): Transaction! @auth
+    generateInvoice(invoice: GenerateInvoiceInput!): Transaction! @auth
   }
   type Success {
     status: Boolean!
@@ -45,6 +47,8 @@ module.exports = gql`
 
   type Transaction {
     id: ID!
+    category: Category
+    company: Company
     flow: Flow!
     state: State!
     user: User!
@@ -55,6 +59,21 @@ module.exports = gql`
     file: String
     VAT: Int
     type: TransactionType!
+    ref: String
+  }
+
+  type Category {
+    id: ID!
+    name: String!
+  }
+
+  type Company {
+    name: String!
+    email: String
+    phone: String
+    VAT: String
+    bankDetails: BankDetails
+    address: Address
   }
 
   #inputs
@@ -89,12 +108,42 @@ module.exports = gql`
   input Expense {
     amount: Float!
     date: String
-    expDate: String
     description: String!
     receipt: Upload!
     VAT: Int
   }
 
+  input InvoiceUpload {
+    amount: Float!
+    date: String
+    category: String
+    company: CompanyInput
+    expDate: String
+    invoice: Upload!
+    VAT: Int
+  }
+
+  input CompanyInput {
+    id: ID
+    name: String
+    email: String
+    phone: String
+    VAT: String
+    bankDetails: BankDetailsInput
+    address: AdressInput
+  }
+
+  input GenerateInvoiceInput {
+    company: CompanyInput!
+    details: [GenerateInvoiceDetailsInput!]!
+    VAT: Int!
+  }
+
+  input GenerateInvoiceDetailsInput {
+    description: String!
+    amount: Float!
+  }
+
   #enums
   enum Flow {
     IN

backend/src/index.js

@@ -15,6 +15,10 @@ const models = require('./models');
 const db = require('./db');
 const auth = require('./auth');
 
+const validation = require('./lib/validation');
+const constants = require('./constants');
+const generateInvoicePDF = require('./invoiceFactory');
+
 const PORT = process.env.PORT || 4000;
 
 const app = express();
@@ -29,7 +33,18 @@ app.use(
 const context = async ({ req, res }) => {
   const user = await auth.loggedUser(req.cookies, models);
   // adopting injection pattern to ease mocking
-  return { req, res, user, auth, models, cloudinary, db };
+  return {
+    req,
+    res,
+    user,
+    auth,
+    models,
+    cloudinary,
+    db,
+    validation,
+    constants,
+    generateInvoicePDF
+  };
 };
 
 const server = new ApolloServer({
@@ -69,5 +84,8 @@ module.exports = {
   auth,
   server,
   app,
-  cloudinary
+  cloudinary,
+  validation,
+  constants,
+  generateInvoicePDF
 };