Jbdap-interpreter NPM

JBDAP-Node-Interpreter

This package provides a series of functional tools to help developers to interpret a JBDAP-style-json object which is the first thing to write a JBDAP driver.

Install

npm install --save jbdap-interpreter

yarn add jbdap-interpreter

Usage

// import tools, set 'zh-cn' as default info language
const { parser, validator, reference, calculator } = require('jbdap-interpreter')('zh-cn')

// then you can use them in your code
validator.checkJSON(json)

APIs

There are four modules here.

1. validator - help to check different kinds of parameters to see whether they are valid

checkJSON(json,lang) - validate whether a json object is a valid JBDAP-json
- params
  - json - Object - target to validate
  - lang - String - the infomation langage, if not passed, use default.
- return - Boolean
- error - throw a NiceError object directly.
checkCommand(cmd,lang) - check whether a jbdap command object is valid
- params
  - cmd - Object - target to check
  - lang - String - the infomation langage, if not passed, use default.
- return - Boolean
- error - throw a NiceError object directly.
checkTopCommand(cmd,lang) - just like checkCommand except we require this command to be a top level command
safeString(cmd,lang) - process a string to an xss-free one.
- params
  - str - String - the string to be processed.
- return - String - the new safe string
hasSqlInjection(cmd,lang) - check whether a string has sql injection dangers
- params
  - str - String - the string to be checked
- return - Boolean

2. parser - help to parse different kinds of configurations in JBDAP-style-json

parseComparision(type,key,value,lang) - parse a condition key-value-pair to a comparision structure
- params
  - type - String - 'compare' for reference and 'query' for 'query.where'
  - key - String - the key of the condition key-value-pair
  - value - String|Any - the value of the condition key-value-pair
  - lang - String - the infomation langage, if not passed, use default.
- return - Object
```
// for example:
{
    left: 'price',
    operator: 'gte',
    right: 150
}
```

parseFields(fields,lang) - parse 'fields' property in JBDAP command

params
- fields - String|ArrayObject - target to parse
- lang - String - the infomation langage, if not passed, use default.

return - Object - parsed structure

raw - Array - the field names you want in a table

// for example:
[
    'id',
    'name',
    { lastVisited: 'updatedAt' },  // lastVisited is the alias of updatedAt
    ...
]

values - Array - the data you want to get in a 'values' type command

// for example:
[
    {
        name: 'userCount',
        operator: 'count',
        fields: 'id'
    },
    ...
]

cascaded - Array - the cascaded fields which have the same structure as a top query command

// for example:
[
    {
        name: 'top5blogs',
        type: 'list',
        target: 'blogs',
        fields: '*',
        query: {
            where: {
                'userId#eq': '$.id'
            }
        }
    },
    ...
]

parseOrder(order,lang) - parse 'query.order' property in JBDAP command
- params
  - order - String|ArrayString - target to parse
  - lang - String - the infomation langage, if not passed, use default.
- return - Array - parsed structure
```
// for example:
[
    {
        column: 'updatedAt',
        order: 'desc'
    },
    {
        column: 'categoryId',
        order: 'asc'
    }
]
```
parseOffsetAndLimit(page,size,lang) - parse 'query.page' and 'query.size' to a structure
- params
  - page - Integer - query.page
  - size - Integer - query.size
  - lang - String - the infomation langage, if not passed, use default.
- return - Object
```
// for example:
{
    offset: 90,
    limit: 10
}
```

3. calculator - do calculations for many places

checkCondition(type,obj,relation,root,parent,self,lang) - calculate the result of a condition object
- params
  - type - String - 'compare' for 'onlyIf' structure and 'query' for 'query.where' in reference
  - obj - Object - the structure to calculate
  - relation - String - the relation between top properties, allows and|or|not
  - root - Object - the root data space
  - parent - Object - the node this calculation belongs to
  - self - the node data itself
  - lang - String - the infomation langage, if not passed, use default.
- return - Boolean
compare(comparision,root,parent,self,lang) - calculate the result of a condition object
- params
  - comparision - Object - the structure which has been parsed by parser.parseComparision()
  - root - Object - the root data space
  - parent - Object - the node this calculation belongs to
  - self - the node data itself
  - lang - String - the infomation langage, if not passed, use default.
- return - Boolean
tag2value(tag,root,parent,self,lang) - convert a tag to value it presents
- params
  - tag - String - the tag to convert
  - root - Object - the root data space
  - parent - Object - the node this calculation belongs to
  - self - the node data itself
  - lang - String - the infomation langage, if not passed, use default.
- return - Any
getValue(list,obj,lang) - get a specified value from a data list, this is used in 'values' type command
- params
  - list - ArrayObject - the source data list
  - obj - Object - the structure which is parsed by parser.parseFields(), the 'values' property works in here
  - lang - String - the infomation langage, if not passed, use default.
- return - Any

4. reference - deal with the reference features

getObjFromObj(data,rawFields,lang) - get specified fields from data
- params - Object - the source object
  - rawFields - ArrayString|Object - the structure which is parsed by parser.parseFields(), the 'raw' property works in here
  - lang - String - the infomation langage, if not passed, use default.
- return - Object
getObjFromList(data,query,rawFields,root,parent,lang) - find one entity from a referenced data list, if there are many, take the first one
- params
  - data - ArrayObject - the source data list
  - query - Object - a 'query' definition in JBDAP command
  - rawFields - ArrayString|Object - the fields structure which is parsed by parser.parseFields(), the 'raw' property works in here
  - root - Object - the root data space
  - parent - Object - the node this calculation belongs to
  - lang - String - the infomation langage, if not passed, use default.
- return - Object
getListFromList(data,query,rawFields,root,parent,lang) - execute a query and fetch the ones which fits the specified condition
- params
  - data - ArrayObject - the source data list
  - query - Object - a 'query' definition in JBDAP command
  - rawFields - ArrayString|Object - the fields structure which is parsed by parser.parseFields(), the 'raw' property works in here
  - root - Object - the root data space
  - parent - Object - the node this calculation belongs to
  - lang - String - the infomation langage, if not passed, use default.
- return - ArrayObject
getValuesFromList(data,valuesFields,lang) - calculate the values you need from a data list, this is used by 'values' type command
- params
  - data - ArrayObject - the source data list
  - valuesFields - ArrayObject - the fields structure which is parsed by parser.parseFields(), the 'values' property works in here