From e019db37a2eeee60928dee6f0a1ea7e8f9cb525a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Juli=C3=A1n=20L=C3=B3pez=20Ca=C3=B1a?=
 <rjlopezmad@gmail.com>
Date: Tue, 2 Apr 2019 23:00:42 +0200
Subject: [PATCH] feat(filter): add not operator

---
 src/field-filter.ts   | 10 ++++++++--
 src/filter-factory.ts |  5 +++--
 src/lookup.enum.ts    |  3 ++-
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/field-filter.ts b/src/field-filter.ts
index 919c3ad..32ee055 100644
--- a/src/field-filter.ts
+++ b/src/field-filter.ts
@@ -1,11 +1,14 @@
 import { AbstractFilter } from './filter';
 import { LookupFilter } from './lookup.enum';
-import { Like, IsNull, LessThan, LessThanOrEqual, MoreThan, MoreThanOrEqual, In, Between } from 'typeorm';
+import { Like, IsNull, LessThan, LessThanOrEqual, MoreThan, MoreThanOrEqual, In, Between, Not } from 'typeorm';
 
 export class FieldFilter extends AbstractFilter {
 
-  constructor(query: any, prop: string, lookup: LookupFilter, value: string) {
+  private notOperator: boolean;
+
+  constructor(query: any, prop: string, lookup: LookupFilter, value: string, notOperator: boolean = false) {
     super(query, prop, lookup, value);
+    this.notOperator = notOperator;
   }
 
   public buildQuery() {
@@ -48,6 +51,9 @@ export class FieldFilter extends AbstractFilter {
         queryToAdd = { [this.prop]: Between(+rangeValues[0], +rangeValues[1]) };
         break;
     }
+    if(this.notOperator) {
+      queryToAdd[this.prop] = Not(queryToAdd[this.prop]);
+    }
     this.query['where'] = {
       ...this.query['where'],
       ...queryToAdd
diff --git a/src/filter-factory.ts b/src/filter-factory.ts
index 0a3d69c..089ac13 100644
--- a/src/filter-factory.ts
+++ b/src/filter-factory.ts
@@ -7,10 +7,11 @@ export class FilterFactory {
   public get(query: any, key: string, value: string): AbstractFilter {
     if (this.isFieldFilter(key)) {
       const field = key.split(LookupDelimiter.LOOKUP_DELIMITER)[0];
+      const notQuery = key.includes(`${LookupDelimiter.LOOKUP_DELIMITER}${LookupFilter.NOT}`);
       const lookup = key.includes(LookupDelimiter.LOOKUP_DELIMITER)
-        ? key.split(LookupDelimiter.LOOKUP_DELIMITER)[1] as LookupFilter
+        ? key.split(LookupDelimiter.LOOKUP_DELIMITER)[notQuery ? 2 : 1] as LookupFilter
         : LookupFilter.EXACT;
-      return new FieldFilter(query, field, lookup, value);
+      return new FieldFilter(query, field, lookup, value, notQuery);
     }
   }
 
diff --git a/src/lookup.enum.ts b/src/lookup.enum.ts
index f65b2dc..03ac090 100644
--- a/src/lookup.enum.ts
+++ b/src/lookup.enum.ts
@@ -9,7 +9,8 @@ export enum LookupFilter {
   STARTS_WITH = 'startswith',
   ENDS_WITH = 'endswith',
   IN = 'in',
-  BETWEEN = 'between'
+  BETWEEN = 'between',
+  NOT = 'not',
 }
 
 export enum LookupDelimiter {