json view in a grails service

posts/how-to-use-a-grails-json-view-in-a-service.md

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+---
+title: How to use a JSON View in a Grails Service
+summary: You can render a model into JSON with a JSON View within a Grails service. 
+
+author.name: Sergio del Amo
+author.url: https://sergiodelamo.com/me.html
+author.avatar: https://images.sergiodelamo.com/smallavatar.png 
+date_published: 2021-09-22T14:56:34+01:00
+date_modified: 2021-09-22T14:56:34+01:00
+keywords:grails
+---
+
+# [%title]
+
+You can render a model into JSON with a [JSON View](http://views.grails.org/latest/#_json_views) within a [Grails](https://grails.org) service: 
+
+Given the following view:
+
+`grails-app/views/apiContact/_contact.gson`
+
+```groovy
+import example.Contact
+
+model {
+    Contact contact
+}
+json {
+    fullname contact.name
+}
+```
+
+You can create a service such as: 
+
+```groovy
+package example
+
+import grails.plugin.json.view.JsonViewTemplateEngine
+import groovy.text.Template
+import org.springframework.beans.factory.annotation.Autowired
+
+class JsonViewRenderingService {
+    @Autowired
+    JsonViewTemplateEngine jsonViewTemplateEngine
+
+    Writable renderWritable(String templatePath, Map<String, Object> model) {
+        jsonViewTemplateEngine.resolveTemplate(templatePath)
+            .make(model)
+    }
+
+    String render(String templatePath, Map<String, Object> model) {
+        renderWritable(templatePath, model)
+            .writeTo(new StringWriter())
+            .toString()
+    }
+}
+```
+
+Which you can call from other Grails Artifacts: 
+
+```groovy
+jsonViewRenderingService.render('/apiContact/_contact',
+[contact: new Contact(name: 'Sergio')])
+```
+
+Kudos to [@virtualdogbert](https://twitter.com/virtualdogbert) for this trick.
+
+
+