server/models/utils.ts

   1 // Translate for example "-name" to [ [ 'name', 'DESC' ], [ 'id', 'ASC' ] ]
   2 import { Sequelize } from 'sequelize-typescript'
   3
   4 function getSort (value: string, lastSort: string[] = [ 'id', 'ASC' ]) {
   5   let field: any
   6   let direction: 'ASC' | 'DESC'
   7
   8   if (value.substring(0, 1) === '-') {
   9     direction = 'DESC'
  10     field = value.substring(1)
  11   } else {
  12     direction = 'ASC'
  13     field = value
  14   }
  15
  16   // Alias
  17   if (field.toLowerCase() === 'match') field = Sequelize.col('similarity')
  18
  19   return [ [ field, direction ], lastSort ]
  20 }
  21
  22 function getSortOnModel (model: any, value: string, lastSort: string[] = [ 'id', 'ASC' ]) {
  23   let [ firstSort ] = getSort(value)
  24
  25   if (model) return [ [ model, firstSort[0], firstSort[1] ], lastSort ]
  26   return [ firstSort, lastSort ]
  27 }
  28
  29 function throwIfNotValid (value: any, validator: (value: any) => boolean, fieldName = 'value') {
  30   if (validator(value) === false) {
  31     throw new Error(`"${value}" is not a valid ${fieldName}.`)
  32   }
  33 }
  34
  35 function buildTrigramSearchIndex (indexName: string, attribute: string) {
  36   return {
  37     name: indexName,
  38     fields: [ Sequelize.literal('lower(immutable_unaccent(' + attribute + '))') as any ],
  39     using: 'gin',
  40     operator: 'gin_trgm_ops'
  41   }
  42 }
  43
  44 function createSimilarityAttribute (col: string, value: string) {
  45   return Sequelize.fn(
  46     'similarity',
  47
  48     searchTrigramNormalizeCol(col),
  49
  50     searchTrigramNormalizeValue(value)
  51   )
  52 }
  53
  54 function createSearchTrigramQuery (col: string, value: string) {
  55   return {
  56     [ Sequelize.Op.or ]: [
  57       // FIXME: use word_similarity instead of just similarity?
  58       Sequelize.where(searchTrigramNormalizeCol(col), ' % ', searchTrigramNormalizeValue(value)),
  59
  60       Sequelize.where(searchTrigramNormalizeCol(col), ' LIKE ', searchTrigramNormalizeValue(`%${value}%`))
  61     ]
  62   }
  63 }
  64
  65 // ---------------------------------------------------------------------------
  66
  67 export {
  68   getSort,
  69   getSortOnModel,
  70   createSimilarityAttribute,
  71   throwIfNotValid,
  72   buildTrigramSearchIndex,
  73   createSearchTrigramQuery
  74 }
  75
  76 // ---------------------------------------------------------------------------
  77
  78 function searchTrigramNormalizeValue (value: string) {
  79   return Sequelize.fn('lower', Sequelize.fn('immutable_unaccent', value))
  80 }
  81
  82 function searchTrigramNormalizeCol (col: string) {
  83   return Sequelize.fn('lower', Sequelize.fn('immutable_unaccent', Sequelize.col(col)))
  84 }