MWLUG 2014

The Road to Damascus – A Conversion Experience:

LS and @Formula to SSJS

Matthew Fyleman, Product and Project Manager

Who am I?

• Matthew Fyleman

• 21 Years as a Notes/Domino Developer

• Mostly Working on:

– Xpages conversions

– Product development

What is this Talk About?

• Based on My Experiences

• Converting LotusScript and @Formula

to SSJS

• Tools that can help – particularly

regular expressions

What am I talking about?

• When should you convert existing code?

• Conversion Options– NotesAgent.run() with parameter doc

– Search and Replace

– Dedicated Tools

• Search and Replace– Preparation

– Introduction to Regular Expressions

– Examples and Demonstration

– Tips and Traps

• Dedicated Tools

• Questions

When should you convert code?

Never!

When should you convert code?

What is the problem?

• It is always going to be slow

• GIGO

• You will introduce new bugs

• Re-developing will be quicker, cheaper

and you will end up with a better result

• But if you really must ...

Conversion Options

What are your options?

• NotesAgent.run()

– Quick and Dirty

– Agent must run independently

– Only use when agents are available and time is critical

• Search and Replace

– LotusScript -> JavaScript (and Java)

– Less useful for @Formula

• Dedicated Tools

– @Formula

LotusScript to SSJS - Preparation

• Search and Replace is most useful for LS conversion

– Syntactically similar

• Easiest if you do a little refactoring first

– Option Declare

– doc.field(0) -> doc.getItemValue(“Field“)(0)

– Camel Case Notes Objects

– Make Sure Method calls are consistently named

• Best to Avoid All-In-One-Go

– Function or Sub at a Time

Regular Expressions

• Regular Expressions are your new BFF

• Sophisticated Pattern Matching

• Elements from search can be carried through to

replace

• The Search and Replace built in to DDE can use

Regular Expressions

• Useful outside LS conversion (e.g. Validation)– See Planet Lotus - http://planetlotus.org/profiles/ross-swick_97733

Starting Simple – Dim

• Tidy up first – Option Declare, remove clustering e.g.:

Dim x as Integer,y as Integer,z as Integer

• We want to match any variable name in the pattern:

Dim <var name> As <Any valid type>

• Fairly simple:

Dim[ ]+[A-Za-z0-9_]+[ ]+As[ ]+(Integer|String|Boolean|Double|Variant)

• But how do we replace?– Modify the search:

Dim[ ]+([\w]*)[ ]+As[ ]+String

– Use this for replace

var \1 = “”;

Starting Simple – Dim (2)

• For Notes Objects, Things are simpler

Dim <var name> As Notes<rest of object name>

- Ignore ... As New NotesSession for now

• Also, initialising in SSJS, = null is ok:

var <var name>:Notes<rest of object name> = null;

• So our terms are:– Search:

Dim[ ]+([\w]*)[ ]+As[ ]+(Notes[\w]*)

– Replace:

var \1\:\2 = null;

Less simple – If Statements

• For the most part, simple S & R (but order is important):End If to }

[ ]*Then to \) {

Else[ ]+If[ ]*to } else if \(

If[ ]* to if \(

• But what about:

If (x = 10) Then

• Use Search: If[ ]+([\w\(\)\[\]\.<>" ]*)=([\w\(\)\[\]\.<> "]*)[ ]+Then

• Use Replace: if \(\1==\2\) \{

• NB: Works but not optimal!

• Other comparison operators not a problem

! – session objects

• The problem:

• Session object is global in ssjs: ‘session’

• In LS it is created:

Dim sess As New NotesSession

• Need to find all LS session objects, and replace with session

• How do you get a list of session object names?

You need a coffee!

Adding Java

• Java String Object has regex search and replace

String source = “Dim x As String”;

String result = source.replaceAll(“Dim[ ]+([\w]*)[ ]+As[ ]+String”, “var $1 = \“\”;”);

• Pattern and Matcher objects make this even more powerful

Pattern p = Pattern.compile(pattern);Matcher m = p.matcher(this.source);int startPos = 0;while (m.find(startPos)) {

if (!itemList.contains(m.group(1))) {itemList.add(m.group(1));

} startPos = m.end() + 1;

}

Field Handling

• Similar Issue to Session

• Need to find all document object names, and replace field

handling methods

• Will probably need to handle dot notation

– Arrgghh!

• How do you search for dot notation?

<doc name>\.([^GetItemValue])\([0-9]+\)

• Still hard work!

Search and Replace: Tips & Traps

• There are other types than string!

– Always review and test converted code thoroughly

• Date handling is a pain

– Script libraries can help here – Java?

• Watch out for User interaction and particularly dialogues

Work out your strategies in advance!

Converting Formula

• @Formula JavaScript Wrappers help a lot

– Mostly just ‘;’ to ‘,’, and converting lists to arrays

• Some constructions are obvious:

@SetField(“Field”, Value);

• Goes to:

doc.replaceItemValue(“Field”, Value);

• Or

S: @SetField\([ ]*([\w”]*)[ ]*\,[ ]*([\w”]*)[ ]*\);

R: doc\.replaceItemValue\(\1, \2\);

• But there are some issues ...

@

Formula – List Processing

• No direct equivalent in SSJS for *+, *= *>= etc.

when applied to Lists

• Need to plan for this

• Java Class/Library to provide direct substitute

• Unfortunately, Java does not permit operator

overloading, so has to be a set of methods@!

Formula - @If, @Do and @While

@If(@Contains(_WFData_neu;_Key);"";

@Do(

@Set("_Sachgebiet_Zuordnung";@DbLookup("NOTES":"NOCACHE";"":_ADM$StructureDB;"Workflows";"WFArbeitsanweisung";"Sachgebietzuordnung"));

@If(_Sachgebiet_Zuordnung = "" | !@Contains(_Sachgebiet_Zuordnung;_Key2);@Do(

@Prompt([Ok];"Hinweis";"In der System Struktur VBM wurde für das aktuelle Sachgebiet kein Workflow definiert. Das Dokument wird zum ehemaligen

Kompetenzträger zurückgegeben, damit dieser ein neues Sachgebiet auswählen kann.");

@Set("_Kompetenzträger";Bearbeiter1);

@Set("_tmpintern";5)

);

@Do(

@Prompt([Ok];"Hinweis";"In der System Struktur VBM wurde für das aktuelle Sachgebiet ein neues Sachgebiet konfiguriert. Das Dokument wird zum

Kompetenzträger zurückgegeben, damit dieser das neue Sachgebiet auswählen kann.");

@Set("_neues_Sachgebiet";@Left(@Right(_Sachgebiet_Zuordnung;_key2);"||"));

@Set("_Elements";@Elements(@Explode(@Left(@Left(@Right(_WFData_neu;"||Sachgebiet#");"||"); _neues_Sachgebiet) + _neues_Sachgebiet; "$" )));

@Set("_KompetenzträgerData";@Explode(@Left(@Right(_WFData_neu;"||Kompetenzträger#");"||"); "$"));

@Set("_Kompetenzträger";@Subset(@Subset(_KompetenzträgerData;_Elements);-1));

@Set("_tmpintern";6)

)

)

)

); @!!

Focusing on @If

@!!!• @Formula is a FUNCTION language

• @If is a function not a statement

• In practice:

@SetField(“Author”; @If(Status=“1”; Manager; Salesman));

• Needs to convert to:if (Status == “1”) {

var author = doc.getItemValueString(“Manager”);} else {

var author = doc.getItemValueString(“Salesman”);}doc.replaceItemValue(“Author”, author);

Tools

• Search and Replace can be used for @Formula ->

SSJS ...

• ... but it can only take you so far

• A dedicated tool can go further

– Only real alternative to manual translation for complex

statements

– Time consuming to create

– Still not a silver bullet

Third Party Tools

• Espresso - http://www.ultrapico.com/Expresso.htm

– Good for learning regex, and serious regex dev

– Free!

• GREP

– Sophisticated regex file search

– Where regex started (UNIX grep)!

Resources and Information

• We4IT – www.we4it.com

• OpenNTF – www.openntf.org

• Regex Quick Reference

http://www.night-ray.com/regex.pdf

• Loads of websites for all aspects of regex development

• Mastering Regular Expressions – Jeffrey E.F. Friedl –

O’Reilly Publishing

Questions?

Thank-You!matthew.fyleman@we4it.com