@digigov-oss/auditrecord-postgresql-engine/src/engines/postgresql/PostgreSqlEngine.ts

PostgreSQL storage database for use with audit mechanism of GSIS

//To check this engine you have to have a PostgreSQL database installed and running.
//The database must be configured to allow connections from the host that the application is running on.
//The database must also have the following table:
//table audit_records
//  auditUnit: varchar(255);
//  auditTransactionId: varchar(255);
//  auditProtocol: varchar(255);
//  auditTransactionDate:  varchar(20);
//  auditUserIp: varchar(16);
//  auditUserId: varchar(255);
// if you do not provide the table name, the engine will create it for you.

//You can use Docker to run PostgreSQL for your tests.
//`docker run -d --name audit-postgres -e POSTGRES_PASSWORD=audit --network host postgres`
//`docker exec -it audit-postgres psql -U postgres -h localhost -c "CREATE DATABASE audit;"`
//`docker exec -it audit-postgres psql -U postgres -h localhost -c "CREATE TABLE audit_log (auditUnit varchar(255), auditTransactionId varchar(255), auditProtocol varchar(255), auditTransactionDate varchar(20), auditUserIp varchar(16), auditUserId varchar(255));"`

//You can also map the fields of already existent table to the fields in the audit log.

import Client from 'pg-native';

import { AuditRecord, AuditEngine, DatabaseSettings, PNRESETTYPES } from '@digigov-oss/gsis-audit-record-db';

/**
 * @description AuditEngine implementation
 * @note This class is used to implement the methods that must be implemented by the AuditEngine
 * @class PostgreSqlEngine
 * @implements AuditEngine
 * @param {string} connectionString - connect to db via connection string
 * @param {DatabaseSettings} dbSettings - database settings
 */
export class PostgreSqlEngine implements AuditEngine {
  #table: string;
  #columnNames:AuditRecord;
  #client: any;
  
  /** 
   * @description constructor
   * @param {string} connectionString - connect to db via connection string
   * @param {DatabaseSettings} settings - settings for the database
   * @param {AuditRecord} columnNames - column names
   * @memberof PostgreSqlEngine
   */

  constructor(connectionString:string = "", dbSettings: DatabaseSettings={}) {
    const connection = connectionString!=""?{connectionString}:{};
    this.#table = dbSettings.tableName || "audit_records";
    this.#columnNames = dbSettings.columns || {
        auditUnit: "auditUnit",
        auditTransactionId: "auditTransactionId",
        auditProtocol: "auditProtocol",
        auditTransactionDate: "auditTransactionDate",
        auditUserIp: "auditUserIp",
        auditUserId: "auditUserId"
    }

    this.#client = new Client(connection);
    this.#client.connectSync();

    if (!dbSettings.tableName) {
      this.#client.querySync("CREATE TABLE IF NOT EXISTS "+this.#table+" ("+this.#columnNames.auditUnit+" varchar(255), "+this.#columnNames.auditTransactionId+" varchar(255), "+this.#columnNames.auditProtocol+" varchar(255), "+this.#columnNames.auditTransactionDate+" varchar(20), "+this.#columnNames.auditUserIp+" varchar(16), "+this.#columnNames.auditUserId+" varchar(255));");
    }
  
  }

  /**
   * @description Store a record in the database
   * @param {AuditRecord} record - record to be stored
   * @returns {AuditRecord} - the record stored
   * @memberof FileEngine
   * @method put
   */
  put(record: AuditRecord): AuditRecord {
    const data = JSON.stringify(record, null, 2);
    try {
       this.#client.querySync("INSERT INTO "+this.#table+" ("+this.#columnNames.auditUnit+","+this.#columnNames.auditTransactionId+","+this.#columnNames.auditProtocol+","+this.#columnNames.auditTransactionDate+","+this.#columnNames.auditUserIp+","+this.#columnNames.auditUserId+") \
                        VALUES ('"+record.auditUnit+"','"+record.auditTransactionId+"','"+record.auditProtocol+"','"+record.auditTransactionDate+"','"+record.auditUserIp+"','"+record.auditUserId+"');");
      return record;
    } catch (error) {
      throw error;
    }
  }
  
  /**
   * @description Get a record from the database
   * @param auditTransactionId: string - transaction id
   * @returns {AuditRecord}
   * @memberof FileEngine
   * @method get
   */
  get(auditTransactionId: string): AuditRecord {
    try {
      let data = {} 
          const res = this.#client.querySync("SELECT * FROM "+this.#table+" WHERE "+this.#columnNames.auditTransactionId+"='"+auditTransactionId+"';"); 
        data = res[0];
        return data;
    } catch (error) {
      throw error;
    }
  }

  /**
   * @description Generate a new sequence number
   * @param path
   * @returns number
   * @memberof FileEngine
   * @method seq
   */
    seq():number {
         try {
           this.#client.querySync("CREATE SEQUENCE IF NOT EXISTS "+this.#table+"_seq START 1");
           const res = this.#client.querySync("SELECT nextval('"+this.#table+"_seq');");
           return res[0].nextval; 
        } catch (error) {
          throw error;
        }
    }

  /**
   * @description Generate a new protocol number
   * @param path
   * @returns string
   * @memberof FileEngine
   * @method protocol
   */
  pn(pnreset?:PNRESETTYPES): string {
    try {

      let protocol_split = "aion";
      let protocol_date =  new Date().toISOString().split('T')[0];
      switch(pnreset){
          case "daily":
           protocol_split = protocol_date;
          break;
          case "monthly":
              protocol_split = protocol_date.split('-')[0]+"-"+protocol_date.split('-')[1];
          break;
          case "yearly":
              protocol_split = protocol_date.split('-')[0];
          break;
          case "innumerable":
              protocol_split = "aion";
          break;
      }

        const seqName = "prot"+protocol_split.replace(/-/g, '');
        //create sequence for protocol_split if not exists
        this.#client.querySync("CREATE SEQUENCE IF NOT EXISTS "+seqName+"_seq START 1");
        const res = this.#client.querySync("SELECT nextval('"+seqName+"_seq');");
        return res[0].nextval+"/"+protocol_date;
    } catch (error) {
      throw error;
    }
  }
}

export default PostgreSqlEngine;