DD 6.0.2 - value-from-callout?

Environment

Documentation Grumblings

value-from-callout â€” specifies the location in the XML file of the value to be deployed. Used when deploying data from an external data source.

Issue

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

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Comments

Migrateduser

Looks like you found a problem in the OD docs!

The part about "specifies the location in the XML file of the value ..." was accidently copied over form the other "value-from" descriptions. It actually is the name of the external data source java class that we you want to call to get the value for the column. So you can write a java class that calls your perl script.

Mariam

Migrateduser

FYI: I filed a doc bug.

Mariam

Adam Stoller

Are there any examples of how to do this?
I'll freely admit my lack of expertise with Java (the first/last time I used it was during development of OD 551 ...)

Basically - I need to know pretty much everything:
- Where do I create/put my (presumably) gettime.java source file ?
- Do I just need to have the desired value sent to STDOUT?
- Do I need to [not?] have a newline at the end of the output ?
- Where do I put my (presumably) gettime.class file ?
- What do I need in my classpath in order to build the gettime.class file?
- How do I reference the gettime.class file in the value-from-callout value?

For those so inclined:
- How do I write a simple java program to spit out the current date ?
(I imagine I can find this out quickly enough once I get the other answers ... but I won't look any gift-horses in the mouth ...)

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Migrateduser

Yes.. it's docd pretty well in the DD admin guide. And there are sample classes under odhome/examples/conf-dd/callout.

You have to create a class that extends a DD interface. There is method that you have to implement whose return value is the value of the column.

For the date question .. you can use the class java.lang.System. there is method called currentTimeMillis... you can probably use java.util.Date and java.util.DateFormat to convert that to the format you want.

Something like the following:

import java.lang.System
import java.util.Date
import java.util.DateFormat

public String getDate() {

long timeMil = System.currentTimeMillis();
Date date = new Date(timeMil);
String fdate = DateFormat.getDateInstance(DateFormat.LONG).format(date);
return fdate;
}

Mariam

Adam Stoller

Great - I'll look at those on Monday and post my results (or troubles getting them ;-) when I get around to actually trying to perform the deployment (my guess - Tuesday at the earliest ;-)

Thanks much!

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Adam Stoller

Okay - it's Monday morning and I'm [still] confused over this class stuff.

Do I have to write a class file that looks like the IWDataDeploySample.java file in the examples directory?
Do I need to define:public class GetSysDate implements com.interwoven.dd100.dd.IWExternalDataSource
{
...
//Constructor
public GetSysDate() { ... }
public double GetProtocolVersion() { ... }
public String GetExternalValue(Connection conn, String tableName, String colName, int opCode,
Hashtable tuple, boolean isReplicant)
{ ... }
}I'm guessing I need the constructor (GetSysDate()) - even if it doesn't do anything - yes?
Do I need the GetProtocolVersion() ?
Am I safe to assume that GetExternalValue() is as far as I would need to go and that I could do the date generation stuff you were talking about in your previous post within that function and just return it? Or do I have to do something else?
Do I need that many paramaters for GetExternalValue() or could I actually define it to take no parameters since it doesn't really care much about context or anything and isn't trying to interact with anything except the system time... Or could I role this all into the constructor itself?

If you (or anyone else) replies - please try to remember that your audience (me) is largely Java-Illterate - I understand how to write code in general, I don't understand how to write Java packages, classes, methods, etc.

(it would be sooooo much easier to be able to do something like:

    iwperl -e 'my @tm = localtime;$tm[4]++, $tm[5] += 1900;printf("%d-%d-%d", reverse(@tm[3..5]));'

    iwperl -MDate::Manip -e 'print UnixDate(ParseDate("now"), "%Y-%M-%d");'

and be done with it ;-)

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Adam Stoller

So - this is what I have so far, which I cannot get to compile, so I figure I need some pointers on how to convert this code to something that will work with core classes and how to correctly compile this stuff on a Windows box.package getsysdate;

//import the Interface definition for the Java Callout
import com.interwoven.dd100.dd.IWExternalDataSource;
//import other stuff needed
import java.util.*;
// Does the following come with Java? or is it something I would have to install?
// Is there a more core-like utility for the purpose of creating a formatted string?
import jformatter.text.*;

public class GetSysDate implements com.interwoven.dd100.dd.IWExternalDataSource
{
//Constructor
public GetSysDate() { /* nothing to do at this time */ }

// GetProtocolVersion - interface method to establish handshake with DataDeploy
// currently only supported interface protocol version is 1.0
// Do I need this?
public double GetProtocolVersion() {
return com.interwoven.dd100.dd.IWExternalDataSource.kProtocolVersion10;
}

// GetExternalValue - interface method to supply value
public String GetExternalValue(/* Do I need all those parameters as in the example file? */) {
Calendar now = Calendar.getInstance();
// Is there another way to do this? more core-supported?
String today
= new PrintFormat("%d-%02d-%02d").sprintf(now.get(Calendar.YEAR),
now.get(Calendar.MONTH) + 1,
now.get(Calendar.DAY_OF_MONTH));
return today;
}

}I tried compiling it, but not much joy there:

\Interwoven\TeamSite\local\lib> ..\..\tools\java\bin\javac.exe -classpath d:\Interwoven\OpenDeployNG\lib\dd.jar GetSysDate.java
GetSysDate.java:27: package com.interwoven.dd100.dd does not exist
import com.interwoven.dd100.dd.IWExternalDataSource;
^
GetSysDate.java:33: package jformatter.text does not exist
import jformatter.text.*;
^
GetSysDate.java:35: package com.interwoven.dd100.dd does not exist
public class GetSysDate implements com.interwoven.dd100.dd.IWExternalDataSource
^
GetSysDate.java:43: package com.interwoven.dd100.dd does not exist
return com.interwoven.dd100.dd.IWExternalDataSource.kProtocolVersion10;
^
GetSysDate.java:50: cannot resolve symbol
symbol : class PrintFormat
location: class getsysdate.GetSysDate
= new PrintFormat("%d-%02d-%02d").sprintf(now.get(Calendar.YEAR),
^
5 errors

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Migrateduser

The classpath should have ddcombo.jar not dd.jar ... that's where the DD classes are.

Yes, you do need the constructor, GetProtocolVersion, etc. You also need all the params for GetExternalValue even if you don't use them, otherwise you won't have a proper implementation of the IWExternalDataSource class.

For the non dd classes that are giving compile errors, you prob need another jar ... looks like those are not packaged with the standard java packages. So you'll have to find those packages and import them in your class.

Mariam

Adam Stoller

Thanks for the clarifications - however its possible that this is all for naught -- I'll be making a new thread shortly to describe my dilemma....

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Adam Stoller

Now that I'm looking at trying to write the deployment configuration - I noticed something that might remove the need for me to write this callout altogether (and so I'm asking for verification if this will work).

If instead of declaring my column in the dbschema.cfg like this: <column name="last_update_dt"
data-type="DATETIME"
value-from-callout="some-yet-to-be-defined-callout-string"/>Could I instead define it like this: <column name="last_update_dt"
data-type="DATETIME"
value="_replace_me_"/>and then in my deployment configuration do something like: <substitution name="global_substitution">

<field name="last_update_dt" replace="$today^"/>
</substitution>While the value-from-callout may have its uses - in my case, I think this would be significantly easier to implement and provide the same amount of functionality with far less overhead (the script that invokes the deployment can create the $today variable and pass it in on the command line and replace all occurrences of it in the deployment configuration in one pass - instead of invoking a callout for each and everyone of these fields (there are 18 identical such fields in my dbschema.cfg right now).

Am I correct in my interpretation of the documentation? Does this sound reasonable?

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Migrateduser

That's a cool idea. Sounds good to me. I can't think of any reason why that wouldn't work.

Mariam

Adam Stoller

Great - it's much easier for me - and I believe, in this circumstance - the better solution.
Thanks.

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Migrateduser

I'm sorry. I don't think this will work. DD docs do say that param substitution can not be used for the match attribute. It doesn't say anything about 'replace.' But I just tried it and DD gave me an error. This is probably because 'replace' can have '$' as part of the regex ... see page 131 of the 602 DD admin guide.

Mariam

Adam Stoller

The parameter substitution should be happening in a preprocessing step, before any regex processing of the configuration directives - if it doesn't handle replacing $token^ with the value of -k "today=2005-08-17" - I'd classify that as a significant bug.

The only places where $ is relevant in the replacement regex are:
- at the very end, followed by a quote (single or double - though it should be double-only if we're following Perl semantics)
- folowed immediately by a digit (e.g. $1, $2, $3) where it becomes a reference to a register variable to match a captured portion of the pattern portion of the replace construct.

Any other failure to process a valid $token, especially when followed by the '^' ($token^) is wrong.

I haven't gotten far enough to start testing this - but if it doesn't work now - it should defniitely be fixed.

--fish
Senior Consultant, Quotient Inc.
http://www.quotient-inc.com

Migrateduser

I filed a bug for this #61773.

Mariam

RajatChopra

Has this been fixed? Seems a long long time ago...

We are facing the same issue, while trying to access a command line parameter inside the replace attribute for substitution in DD.

The '$token' is still not recognized as a valid Command line variable. It treats it as a string literal. Smiley Sad

-R