README.md

Portal

Port your MySQL data from old schema to the new schema with just a configuration file.

How to

• Create a config.js file which exports an object with rules and database config.
• npm install
• node index.js

Configuration

config.js must export an object with host, user, password, db and rules. See below for details.

host [String]

• Host for database

user [String]

• User for database

password [String]

• Password for the database

db [Object]

• Must contain source and destination pairs with database names

---

rules [Array]

• Contains the rules for porting
• One rule for each target table
• Example:

  rules: [ {}, {}, ... , {} ]

rules[i].table [Object]

• Object with info about target and source tables
• Must contain: old and new objects
  • new: String
  • old: String or Object with union and on pairs
• See old below for details
• Example:

  table: {
      new: 'NEW_TABLE', 
      old: 'OLD_TABLE'
  }

rules[i].fields [Object]

• Object with target_attributes as keys and source_attributes or other rules as values
• See fields below for details
• Example:

  fields: {
      user: 'login', 
      password: 'pass'
  }

  This SELECTs login and pass fields from old table and puts in user and pass of the new table, respectively

rules[i].query [String]

• A MySQL query to run instead of target and source pairs
• If found, table and fields objects are ignored
• Example:

  query: 'INSERT INTO table (user, password) VALUES ("bits", "goa_ftw!");'

  Runs the query as it is

rules[i].skip [Boolean]

• If true, the rule is skipped
• Example:

  rules: [ { skip: true, ... }, {}, {} ]

  This rule is skipped regardless of anything else

---

rules[i].tables.old [String] or [Object]

• Must be either a string with table name
• Or an object with union and on
  • union must be an array with table names
  • on must be a MySQL condition
• Example:

  old: {
      union: ['t1', 't2', 't3'],
      on: 't1.id = t2.id AND t2.id = t3.id'
  }

  Inner joins the tables with common id

---

rules[i].fields [Object]

fields[0].if [Object]

• Evaluates an if condition and enters data accordingly
• Must contain condition, pass and fail
• See condition below for details
• Example:

  if: {
      condition: {
          eval: {}
      },
      pass: 'login',
      fail: {
          value: 'some other'
      }
  }

  Checks if login attribute of old table is equal to "bits". If yes, puts login of old table in the new table else puts a string "some other"

fields[0].switch [Object]

• Evaluates switch condition and enters data accordingly
• Must contain condition, cases
• cases must be an object of key-value pairs
• Example:

  switch: {
      condition: 'login_type',
      cases: [
          { type1: { value: '1' } },
          { type2: { value: '2' } },
          { other: 'login_type' }
      ]
  }

  If login_type equals "type1" put a string "1" or if "type2" put a string "2" or if "other" put the value of login_type attribute of old table

fields[0].value [String]

• Any field with value will be put as value itself rather than getting it from the source table
• Example:

  user: { value: 'some value' }

  Puts the string "some value" in user attribute of the new table

---

if.condition

rules[i].fields[j].if.condition [Object]

• Must contain eval or or or and
• or or and must be an array of objects which must contain eval
• See eval below for details
• Example:

  condition: {
      or: [
          { eval: {C1} },
          { eval: {C2} },
          {
              and: [
                  { eval: {C3} },
                  { eval: {C4} }
              ]
          }
      ]
  }

  Is equivalent to C1 || C2 || (C3 && C4)

---

if.condition.eval

rules[i].fields[j].switch.condition.eval [Object]

• Must contain operator and (first_attribute or first_value) and (second_attribute or second_value)
  • operator must be a constant string
  • X_attribute must be an attribute of the table
  • X_value must be a constant string
• Example:

  condition: {
      eval:
          operator: '===',
          first_attribute: 'login',
          second_value: 'bits'
      }
      pass: { value: '1' },
      fail: { value: '0' }
  },

  Put "1" or "0" if login of old table is === to bits of new table