server/models/utils.ts

   1 // Translate for example "-name" to [ [ 'name', 'DESC' ], [ 'id', 'ASC' ] ]
   2 import { Sequelize } from 'sequelize-typescript'
   3
   4 type SortType = { sortModel: any, sortValue: string }
   5
   6 function getSort (value: string, lastSort: string[] = [ 'id', 'ASC' ]) {
   7   let field: any
   8   let direction: 'ASC' | 'DESC'
   9
  10   if (value.substring(0, 1) === '-') {
  11     direction = 'DESC'
  12     field = value.substring(1)
  13   } else {
  14     direction = 'ASC'
  15     field = value
  16   }
  17
  18   // Alias
  19   if (field.toLowerCase() === 'match') field = Sequelize.col('similarity')
  20
  21   return [ [ field, direction ], lastSort ]
  22 }
  23
  24 function getSortOnModel (model: any, value: string, lastSort: string[] = [ 'id', 'ASC' ]) {
  25   let [ firstSort ] = getSort(value)
  26
  27   if (model) return [ [ model, firstSort[0], firstSort[1] ], lastSort ]
  28   return [ firstSort, lastSort ]
  29 }
  30
  31 function throwIfNotValid (value: any, validator: (value: any) => boolean, fieldName = 'value') {
  32   if (validator(value) === false) {
  33     throw new Error(`"${value}" is not a valid ${fieldName}.`)
  34   }
  35 }
  36
  37 function buildTrigramSearchIndex (indexName: string, attribute: string) {
  38   return {
  39     name: indexName,
  40     fields: [ Sequelize.literal('lower(immutable_unaccent(' + attribute + '))') as any ],
  41     using: 'gin',
  42     operator: 'gin_trgm_ops'
  43   }
  44 }
  45
  46 function createSimilarityAttribute (col: string, value: string) {
  47   return Sequelize.fn(
  48     'similarity',
  49
  50     searchTrigramNormalizeCol(col),
  51
  52     searchTrigramNormalizeValue(value)
  53   )
  54 }
  55
  56 // ---------------------------------------------------------------------------
  57
  58 export {
  59   SortType,
  60   getSort,
  61   getSortOnModel,
  62   createSimilarityAttribute,
  63   throwIfNotValid,
  64   buildTrigramSearchIndex
  65 }
  66
  67 // ---------------------------------------------------------------------------
  68
  69 function searchTrigramNormalizeValue (value: string) {
  70   return Sequelize.fn('lower', Sequelize.fn('immutable_unaccent', value))
  71 }
  72
  73 function searchTrigramNormalizeCol (col: string) {
  74   return Sequelize.fn('lower', Sequelize.fn('immutable_unaccent', Sequelize.col(col)))
  75 }