Monday, October 31, 2016

Spam email

Sometime spam email is so bad it is pure comedy genius. The amount of things wrong with this opening statement.

It is my pleasure to inform you that Diplomatic Agent Terry has arrive in yournearest Airport today with your package worthy $5.5million you have to contacthim at this email address (diplomaticagentfredjames33@gmail.com

Wednesday, October 26, 2016

Side effects with not having decent UNIT tests

This is not Grails/Groovy specific but in general.

Grails/Groovy is certainly more reliant on tests, as it is dynamically typed, so code needs to be executed to pickup errors. The Java world seems to rely on static typing while Groovy on tests. Tests are always better than typing, period.

Besides the obvious, if it is not tested how do you know it works? There are some interesting side effects I see with poorly unit tested code.

Makes your Code Better

  • Having to write unit tests for a class/method makes your code structurally better.
  • It leads to better separation of concerns. 
  • Starts enforcing the law of Demeter. 
  • Easily tested code is generally easier to understand. 


Documents Code

  • Documentation falls out of date and quickly becomes irrelevant. Properly written tests (Spock helps) is a great way to document code. 


Makes changing existing code possible

  • I cannot change existing if I have no idea if it works, or how it works. 
  • In larger systems knowing if existing code works without tests becomes increasingly difficult.
  • It can be very difficult to execute see what code is doing if you need to stand up the whole system just to test a method.


Quicker to Change and Safer to Change

  • If your code has a unit test you can execute it immediately.
  • You can see changes, and what they do to existing tests immediately
  • 100's of times an hour.

Tuesday, October 25, 2016

Intellij Color Schemes

Found a neat little site with colour schemes for Intellij

http://color-themes.com/?view=index

Once you have downloaded the jar, just go to File->import settings and load that jar.

Friday, October 14, 2016

Grails3 GORM running MongoDB

Had some issues getting Mongo to work with Grails3 based on this doc, ended up creating an example project of it all working

Feel free to download, have a look

Spock data driven testing with interactions (Mocks)

You can do data driven testing with Mocks and interactions, the key is that your interaction should be in the setup: block For Example
    @Unroll
    def "createOtherField test to see if label override works #fieldName override(#fieldLabel) == #resultName"() {
        setup:
        FormFieldMapManager formFieldMapManager = Mock()
        String onlineFormId = '1'
        List<LabelValue> otherFields = []
        1*formFieldMapManager.getMappedFields(onlineFormId, false) >> [new FormFieldMap()]

        expect:
        List<LabelValue> result = ProcessorUtil.createOtherField(formFieldMapManager, onlineFormId, otherFields, fieldName, 'fieldValue')
        result[0].label == resultName

        where:
        fieldName   | fieldLabel    || resultName
        'fieldName' | null          || 'fieldName'
        'fieldName' | ''            || 'fieldName'
        ''          | null          || ''
        'fieldName' | 'OVERRIDE'    || 'OVERRIDE'
    }

Tuesday, October 11, 2016

Intellij H2 Database viewer

For some reason to be able to see you tables in the Intellij H2 DB viewer you have append the following mv_store=false in your application.yml so the connection string looks like so:
jdbc:h2:file:./devDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE;mv_store=false

Monday, September 12, 2016

Flatten a Map of Maps

A question came up that interested me, someone had a map that contains children of possibly lists of other maps, and they wanted to flatten all these maps to count all the values contained in this map of lists of maps. I just used a recursive closure to collect all the values of the maps and lists, flatten that into a list and then an inject (fold) to count up the values.

def collector
collector = {item -> item.collect {element -> element.value instanceof Map ? collector(element.value) : element.value}}

assert 4 == collector([a: [q:1, w:1], b: [e:1], c: 1]).flatten().inject(0) { temp, val -> temp + val.value}
assert 3 == collector([a: [q:1, w:[z:1, x:1]]]).flatten().inject(0) { temp, val -> temp + val.value}

Sunday, September 11, 2016

Grails logging debug from your controller logback.groovy

To get your controllers and services logging debug messages edit your logback.groovy. Just add your package structure, for instance if your package structure was com.myapp

root(ERROR, ['STDOUT']) // Sets log level of all
logger('grails.app.controllers.com.myapp', DEBUG, ['STDOUT'], false) // Turn on debug for all your controllers
logger('grails.app.services.com.myapp', DEBUG, ['STDOUT'], false) // Turn on debug for all your services

Tuesday, June 28, 2016

Rest API Docs Swagger

I had a lot of problems trying to get swagger to work, finally found this resource which sort of worked for me.
First I started getting

Error creating bean with name 'com.github.rahulsom.swaggydoc.ApiController': Injection of autowired dependencies failed;
This was fixed by adding the following to depenedencies
compile "org.grails:grails-dependencies"

The test UserController, User domain worked. But when I added a very simple class of my won it would render on the http://localhost:8080/api page but clicking it did not bring down it operations.

Okay found the reason. For Swaggy to work you need a few crucial things:
  • Your controller needs the @Api annotation

@Api(value = 'ApiFile', description = 'Anything')
class ApiFileTypeController extends RestfulController {
    static responseFormats = ['json', 'xml']
    ApiFileTypeController() {
        super(ApiFileType)
    }
}
  • Your UrlMapping needs the url for the resource

class UrlMappings {

    static mappings = {
        "/$controller/$action?/$id?(.$format)?"{
            constraints {
                // apply constraints here
            }
        }
        "/filetypes"(resource: 'apiFileType')

        "/"(view:"/index")
        "500"(view:'/error')
        "404"(view:'/notFound')
    }
}

Sunday, June 26, 2016

Grails3 Twitter Bootstrap installing a theme

So Grails 3 and twitter boostrap, where is the bootstrap plugin and how do I install a theme?
First there is no plugin (well there are some plugins that seem to modify your scaffoldin, fields plugin) but Grails 3 has bootstrap as standard really.

But you have bought a theme like Material and want to get it into your app.

Get Theme

So download the Material theme unpack it and run the setup (npm install).
Lets say we want to install the jQuery light theme your theme directory should have a structure similar to:
 --Export
     |
     +--AngularJs
     |
     +--Documenation
     |
     +--jQuery
          |
          +--dark
          |
          +--light
               |
               +--css
               |
               +--fonts
               |
               +--img
               |
               +--js
               |
               +--less
               |
               +--media
               |
               +--node_modules
               |
               +--vendors
               |
               Loads html

Copy the entire light directory into your grails directory at the assets location [app]/grails-app/assets
Rename it to material.

If you run the app, you should be able to access your theme material, with the urls like
http://localhost:8080/assets/index.html
http://localhost:8080/assets/css/demo.css

Material.gsp

Now take a material theme html page, like index.html and copy it into your [app]grails-app/views/layouts directory calling it something like material.gsp.

Now lets edit the material.gsp to take out content and render our grails app in there. Find the


<section id="content">

And replace all the content in it so it looks like this. Basically nothing but including a body

<section id="content">
     <g:layoutBody/>
</section>

Replace all links to css and js includes directories to point to the new assets directory in material.gsp so these links

<link href="vendors/bower_components/fullcalendar/dist/fullcalendar.min.css" rel="stylesheet">
<script src="vendors/bower_components/jquery/dist/jquery.min.js"></script>

Become these

<link href="/assets/vendors/bower_components/fullcalendar/dist/fullcalendar.min.css" rel="stylesheet">
<script src="/assets/vendors/bower_components/jquery/dist/jquery.min.js"></script>

Use

Now we just need tell our page to use this new layout so go to your index.gsp and make the head look as follows (change the content)
<head>
    <meta name="layout" content="material"/>
Now your index.gsp page should render in this new theme

Next Steps

This just quickly shows you how to get a theme in, you still need to change the navigation and add whatever content you want, but it is a start

Sunday, June 19, 2016

Grails fiels f:table f:all

Grails uses the field plugin to generate templates for your GSP.
So for instance your gsp with
<fieldset class="form">
    <f:all bean="project"/>
</fieldset>
Will show a form for all the fields on a Bean.
And the following will show a table view

<f:table collection="${projectList}" />
But what if you want to override the styling, that is easy!
But where do you start, it took me a while to find the default templates that are used, you can find them in the plugin.

So right here is the tables one:
<table>
<thead>
<tr>
<g:each in="${domainProperties}" var="p" status="i">
<g:set var="propTitle">${domainClass.propertyName}.${p.name}.label</g:set>
<g:sortableColumn property="${p.name}" title="${message(code: propTitle, default: p.naturalName)}" />
</g:each>
</tr>
</thead>
<tbody>
<g:each in="${collection}" var="bean" status="i">
<tr class="${(i % 2) == 0 ? 'even' : 'odd'}">
<g:each in="${domainProperties}" var="p" status="j">
<g:if test="${j==0}">
<td><g:link method="GET" resource="${bean}"><f:display bean="${bean}" property="${p.name}" displayStyle="${displayStyle?:'table'}" /></g:link></td>
</g:if>
<g:else>
<td><f:display bean="${bean}" property="${p.name}" displayStyle="${displayStyle?:'table'}" /></td>
</g:else>
</g:each>
</tr>
</g:each>
</tbody>
</table>

Wednesday, June 15, 2016

Debugging Grails 3 in Intellij 2016

I got stuck trying to edit run/debug configuration in Intellij to get my Grails project to debug. There where lots of posts about forks etc, etc.
But it is much simpler than that.

Just go to

grails-app/init/webtracker.api/Application

and right click on Application and select Debug 'Application.main()'

There we go
Intellij will remember these and you can get to them quick in the Build menu

Tuesday, June 14, 2016

Grails log your hibernate queries

To log the Hibernate queries that your app is making merely add these to your logback.groovy
logger('org.hibernate.SQL', DEBUG, ['STDOUT'], false)
logger('org.hibernate.type', TRACE, ['STDOUT'], false)
The false eliminated duplicate entries

Legacy DB, Grails & Domain Classes

When having to build Grails apps around a legacy DB, this plugin is a great start.

The DB reverse engineer plugin (works with Grails 3)

It is a good idea to create a Integration test to just check you can access these tables. The integration test will be run on your development envrionment and you will need to have some data in there. Be careful obviously as it is bad practise to rely on existing data, but this helped me get all the mappings properly wired up.
Start with something as simple as:
package com.webtracker.api.prodcat

import com.webtracker.api.Company
import com.webtracker.api.Project
import com.webtracker.api.WpActivationKey
import grails.test.mixin.integration.Integration
import grails.transaction.Rollback
import spock.lang.Specification

/**
 * Sanity domain Integration tests, uses development DB
 *
 * Created by demian on 14/06/16.
 */
@Integration
@Rollback
class DomainSpec extends Specification{

    def setup() {
    }

    def cleanup() {

    }

    void "Can we list and load an activation key"() {
        when:
        def keys = WpActivationKey.list()
        def key1 = WpActivationKey.get keys[0].id
        def key2 = WpActivationKey.findByActivationKey keys[0].activationKey

        then:
        keys.size() > 0
        key1 == key2

    }

    void "Can we list and load a company"() {
        when:
        def companies = Company.list()
        def company1 = Company.get companies[0].id
        def company2 = Company.findByName companies[0].name

        then:
        companies.size() > 0
        company1 == company2
    }

    void "Can we list and load a project"() {
        when:
        def projects = Project.list()

        then:
        projects.size() > 0
    }
}

I ran into a few stumbling blocks, all easily overcome
In my case the auto timestamping did not work out the box (as column names where different), but that was incredibly easy to fix.

Here is my Domain Class snippet
 Date dateCreated
 Long projectId

 static mapping = {
  version false
 }

 static constraints = {
  activationKey maxSize: 100, unique: true
        dateCreated column: 'created_date'
 }

I started getting this error
Caused by: java.sql.SQLException: Value '0000-00-00 00:00:00' can not be represented as java.sql.Timestamp
This is because that is a valid SQL date but not in Gorm, this was fixed by appending the following to application.yml datasource:url: connection string
?zeroDateTimeBehavior=convertToNull

Intellij YES

After years of working in Eclipse and Sublime 3 I decided to give Intellij a chance. I am very impressed.
I am not much of a fan of IDE's that do a lot of magic as I find it leads to lazy programming, and Intellij does a LOT of magic. But it is very very good at it's magic.
The plugins are of superb quality.
So impressed I bought it.
It even has groovy repl debugging
I also find it faster than eclipse (though I did recently change to an SSD, but I also used it on a regular HD) It also works great in Ubuntu

Back in Grails World and So Happy (Interceptor)

I have the opportunity to develop some in Grails again and I am just so happy. Just a breath of fresh air.

Had to build a simple token authentication for a restful web service.

Ended up with this code using the Grails 3 Interceptor.
I find it readable, concise and clear. (By the way generated this code below with hilite.me great tool)
package com.webtracker.api.prodcat

import grails.compiler.GrailsCompileStatic
import grails.converters.JSON
import org.apache.catalina.connector.Response

/**
 * This method is expensive as it can be called before every controller
 */
@GrailsCompileStatic
class TokenInterceptor {

    TokenInterceptor() {
        matchAll()
    }

    boolean before() {
        if (params?.apikey) {
            WpActivationKey key = WpActivationKey.findByActivationKey(params?.apikey)
            if (key) {
                true
            } else {
                response.status = Response.SC_FORBIDDEN
                render([errors: ['api key not valid']] as JSON)
                false
            }
        } else {
            response.status = Response.SC_FORBIDDEN
            render([errors: ['no api key specified']] as JSON)
            false
        }
    }

    boolean after() {
        true
    }

    void afterView() {
        // no-op
    }
}

Just remember to make your Domain class cacheable so you do not have to query all the time
@Cacheable("activationKeys")