Flex Scripting: Basic Scripting Advice

The following provides a simple guide to writing Flex scripts, in orrder to make scripts as small and efficient as possible.

Variable declaration

Aim to usedefrather than the class name, as it leads to more compact code (IDEs will still be able to provide auto-completion):

// bad 
Long count = 123L
NewAssetPlaceholder assetPl = NewAssetPlaceholder.builder()
        .type('media-asset')
        .name('demo asset')
        .build()

// good 
def count = 123L
def assetPl = NewAssetPlaceholder.builder()
        .type('media-asset')
        .name('demo asset')
        .build()

It is also good practise to declare variables as close as possible to where they are used:

// bad 
def enabled = isUdoEnabled() && isParentUdo()
def assetPl = NewAssetPlaceholder.builder()
        .type('media-asset')
        .name('demoasset')
        .build()
if (enabled) {
    def asset = assetService.createAsset(assetPl)
}

// good 
def enabled = isUdoEnabled() && isParentUdo()
if (enabled) {
    def assetPl = NewAssetPlaceholder.builder()
            .type('media-asset')
            .name('demo asset')
            .build()
    def asset = assetService.createAsset(assetPl)
}

Variable case

Use camel-case for variables:

// bad
def Outputmessage ='my message'
def outputmessage ='my message'

// good
def outputMessage ='my message'

Flex model object instantiation

This model instantiation should be avoided as it is verbose:

// bad
def assetPl = new NewAssetPlaceholder()
assetPl.type = 'media-asset'
assetPl.name = 'demo asset'

// good
def assetPl = NewAssetPlaceholder.builder()
        .type('media-asset')
        .name('demo asset')
        .build()

// also good
def assetPl = new NewAssetPlaceholder([type: 'media-asset', name: 'demo assert"'])

Strings

Single quotes should be used when not performing string interpolation:

// bad 
def myValue ="some value"

// good 
def myValue ='some value'

It is better to use string interpolation rather than string concatenation, especially with long strings, as it makes it easier to comprehend:

// bad 
def myValue = size + " annotations added to assetID " + assetId + " in " + time + "seconds"

// good 
def myValue = "$size annotations added to asset ID $assetId in $time seconds"

Semicolons

Semicolons are not necessary in Groovy, and it is recommended not to use them (inline with the [Apache Groovy Style Guide] (http://groovy-lang.org/style-guide.html)).

ifstatements

Avoid the use ofifstatements without curly braces, as it is easy to introduce logic errors if you do not:

// bad 
if (somevalue)
    callMyFunction()

// good 
if (somevalue) {
    callMyFunction()
}

Close All Streams

Be sure to close any streams that are opened. Any class that inherits from Closable should be closed. For example, the first example here is bad practice because JVM resources are leaked and the second syntax should be used:

// bad 
def execute() {
    def fis = new FileInputStream('/flex/flex-enterprise/storage/media/Subtitle.vtt')
    def data = IOUtils.toString(fis, Charset.defaultCharset())
}

// good 
def execute() {
    def data
    try (def fis = new FileInputStream('/flex/flex-enterprise/storage/media/Subtitle.vtt')) {
        data = IOUtils.toString(fis, Charset.defaultCharset())
    }
}

HttpURLConnection con = (HttpURLConnection) url.openConnection()
try {
    int status = con.getResponseCode()
} finally {
    con.disconnect()
}

Check for Cancelled Jobs and Exit a Script

To improve performance and stops scripts from running even when a job is cancelled, the option `isCancelled()` is exposed from Groovy SDK to allow JEF SDK to check if a job has been cancelled and exit the script (e.g.: context.executionService.isCancelled(context.executionId)). For example, a script that is blocking execution in a loop is not cancelled when the job is cancelled from Enterprise. Using this method, you can check for the job status and implement a method to exit the script.

def execute(){
while(!context.executionService.isCancelled(context.executionId)){
context.logInfo("running")
Thread.sleep(60000);
context.logInfo("afterSleep")
}
context.logInfo("cancelled")
}