back/methods/postcode/filter.js

@@ -0,0 +1,77 @@
+const {ParameterizedSQL} = require('loopback-connector');
+const {buildFilter, mergeFilters} = require('vn-loopback/util/filter');
+// const {models} = require('vn-loopback/server/server');
+
+module.exports = Self => {
+    Self.remoteMethod('filter', {
+        description:
+        'Find all postcodes of the model matched by postcode, town, province or country.',
+        accessType: 'READ',
+        returns: {
+            type: ['object'],
+            root: true,
+        },
+        accepts: [
+            {
+                arg: 'filter',
+                type: 'object',
+                description: 'Filter defining where, order, offset, and limit - must be a JSON-encoded string',
+                http: {source: 'query'}
+            },
+            {
+                arg: 'search',
+                type: 'string',
+                description: 'Value to filter',
+                http: {source: 'query'}
+            },
+        ],
+        http: {
+            path: `/filter`,
+            verb: 'GET',
+        },
+    });
+    Self.filter = async(ctx, filter, options) => {
+        const myOptions = {};
+
+        if (typeof options == 'object')
+            Object.assign(myOptions, options);
+
+        const conn = Self.dataSource.connector;
+        const where = buildFilter(ctx.args, (param, value) => {
+            switch (param) {
+            case 'search':
+                return {or: [
+                    {'pc.code': {like: `%${value}%`}},
+                    {'t.name': {like: `%${value}%`}},
+                    {'p.name': {like: `%${value}%`}},
+                    {'c.country': {like: `%${value}%`}}
+                ]
+                };
+            }
+        }) ?? {};
+
+        filter = mergeFilters(ctx.args?.filter ?? {}, {where});
+
+        const stmts = [];
+        let stmt;
+        stmt = new ParameterizedSQL(`
+        SELECT
+            pc.code,
+            t.name as town,
+            p.name as province,
+            c.country
+        FROM
+            postCode pc
+            JOIN town t on t.id = pc.townFk
+            JOIN province p on p.id = t.provinceFk
+            JOIN country c on c.id = p.countryFk
+        `);
+
+        stmt.merge(conn.makeSuffix(filter));
+        const itemsIndex = stmts.push(stmt) - 1;
+
+        const sql = ParameterizedSQL.join(stmts, ';');
+        const result = await conn.executeStmt(sql, myOptions);
+        return itemsIndex === 0 ? result : result[itemsIndex];
+    };
+};

back/methods/postcode/specs/filter.spec.js

@@ -0,0 +1,103 @@
+const {models} = require('vn-loopback/server/server');
+
+describe('Postcode filter()', () => {
+    it('should retrieve with no filter', async() => {
+        const tx = await models.Postcode.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            const ctx = {
+                args: {
+
+                },
+            };
+            const results = await models.Postcode.filter(ctx, options);
+
+            expect(results.length).toBeGreaterThan(0);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should retrieve with filter as postcode', async() => {
+        const tx = await models.Postcode.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            const ctx = {
+                args: {
+                    search: 46,
+                },
+            };
+            const results = await models.Postcode.filter(ctx, options);
+
+            expect(results.length).toEqual(4);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should retrieve with filter as city', async() => {
+        const tx = await models.Postcode.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            const ctx = {
+                args: {
+                    search: 'Alz',
+                },
+            };
+            const results = await models.Postcode.filter(ctx, options);
+
+            expect(results.length).toEqual(1);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should retrieve with filter as province', async() => {
+        const tx = await models.Postcode.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            const ctx = {
+                args: {
+                    search: 'one',
+                },
+            };
+            const results = await models.Postcode.filter(ctx, options);
+
+            expect(results.length).toEqual(4);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+
+    it('should retrieve with filter as country', async() => {
+        const tx = await models.Postcode.beginTransaction({});
+        const options = {transaction: tx};
+
+        try {
+            const ctx = {
+                args: {
+                    search: 'Ec',
+                },
+            };
+            const results = await models.Postcode.filter(ctx, options);
+
+            expect(results.length).toEqual(1);
+            await tx.rollback();
+        } catch (e) {
+            await tx.rollback();
+            throw e;
+        }
+    });
+});

back/models/postcode.js

@@ -1,6 +1,7 @@
 let UserError = require('vn-loopback/util/user-error');
 
 module.exports = Self => {
+    require('../methods/postcode/filter.js')(Self);
     Self.rewriteDbError(function(err) {
         if (err.code === 'ER_DUP_ENTRY')
             return new UserError(`This postcode already exists`);