machinepack-postgresql/test/integration/transactional/commit-transaction.js

Structured Node.js bindings for connecting and running queries against a PostgreSQL database.

var assert = require('assert');
var Pack = require('../../../');

describe('Transactional ::', function() {
  describe('Commit Transaction', function() {
    var manager;
    var connectionA;
    var connectionB;

    // Create a manager, two connections, and a table
    before(function(done) {
      // Needed to dynamically get the host using the docker container
      var host = process.env.POSTGRES_1_PORT_5432_TCP_ADDR || 'localhost';

      Pack.createManager({
        connectionString: 'postgres://mp:mp@' + host + ':5432/mppg'
      })
      .exec(function(err, report) {
        if (err) {
          return done(err);
        }

        // Store the manager
        manager = report.manager;

        Pack.getConnection({
          manager: manager
        })
        .exec(function(err, report) {
          if (err) {
            return done(err);
          }

          // Store the connection
          connectionA = report.connection;

          Pack.getConnection({
            manager: manager
          })
          .exec(function(err, report) {
            if (err) {
              return done(err);
            }

            // Store the connection
            connectionB = report.connection;

            // Create a table to use for testing
            Pack.sendNativeQuery({
              connection: connectionA,
              nativeQuery: 'CREATE TABLE IF NOT EXISTS people(id serial primary key, name varchar(255));'
            })
            .exec(function(err) {
              if (err) {
                return done(err);
              }

              return done();
            });
          });
        });
      });
    });

    // Afterwards destroy the table and release the connections
    after(function(done) {
      Pack.sendNativeQuery({
        connection: connectionA,
        nativeQuery: 'DROP TABLE people;'
      })
      .exec(function(err) {
        if (err) {
          return done(err);
        }

        Pack.releaseConnection({
          connection: connectionA
        })
        .exec(function(err) {
          if (err) {
            return done(err);
          }

          Pack.releaseConnection({
            connection: connectionB
          }).exec(done);
        });
      });
    });

    // To Test:
    // * Open a transaction on connectionA and insert a record into the DB
    // * Run a query on connectionB and make sure the record doesn't exist
    // * Commit the transaction
    // * Run the select query again and the record should exist
    it('should perform a transaction and make sure the results are commited correctly', function(done) {
      // Start a transaction on connection A
      Pack.beginTransaction({
        connection: connectionA
      })
      .exec(function(err) {
        if (err) {
          return done(err);
        }

        // Insert a record using the transaction
        Pack.sendNativeQuery({
          connection: connectionA,
          nativeQuery: 'INSERT INTO "people" (name) VALUES (\'hugo\') returning "id";'
        })
        .exec(function(err) {
          if (err) {
            return done(err);
          }

          // Query the table using connection B and ensure the record doesn't exist
          Pack.sendNativeQuery({
            connection: connectionB,
            nativeQuery: 'SELECT * FROM "people";'
          })
          .exec(function(err, report) {
            if (err) {
              return done(err);
            }

            // Ensure no results were returned
            assert.equal(report.result.rowCount, 0);

            // Commit the transaction
            Pack.commitTransaction({
              connection: connectionA
            })
            .exec(function(err) {
              if (err) {
                return done(err);
              }

              // Query the table using connection B and ensure the record does exist
              Pack.sendNativeQuery({
                connection: connectionB,
                nativeQuery: 'SELECT * FROM "people";'
              })
              .exec(function(err, report) {
                if (err) {
                  return done(err);
                }

                // Ensure 1 result was returned
                assert.equal(report.result.rowCount, 1);

                return done();
              });
            });
          });
        });
      });
    });
  });
});