topic Re: Loop through input file to populate context variable to be used in job in Talend Studio

Loop through input file to populate context variable to be used in job

tale103108 — Thu, 02 Jul 2015 20:34:18 GMT

Talend 5.4
Linux 6.2
I want to read a text file that contains one value per row, use that value to populate a context variable (or a variable) and then go to a sub job that uses the variable, then repeat through file (and the process) until the end of file.
How to do?
Thank you all.

Re: Loop through input file to populate context variable to be used in job

Anonymous — Fri, 03 Jul 2015 09:50:26 GMT

Hi,
From your description, it seems that you are looking for tContextLoad or Implicit tContextLoad.
Could you please take a look at component: TalendHelpCenter:tContextLoad
and a forum about How to use Implicit tContextLoad in use case https://community.talend.com/t5/Design-and-Development/resolved-Iterate-through-a-list-of-URL-s-for-tRSSInput/td-p/94539 to see if it is satisfying your needs?
Best regards
Sabrina

Re: Loop through input file to populate context variable to be used in job

tale103108 — Thu, 09 Jul 2015 15:32:40 GMT

In the link you provided, if you look at some of the responses, Shong comes close to what I am looking for when he states the following:

You can use tFlowToIterate to iterate all rowss one by one, for example:
tFileInputDelimited--main(row1)-->tFlowToIterate--iterate--tRSSInput--main--tLogRow
on tRSSInput, set the RSS URL field as: row1.url

However, what I need in place of the tRSSInput would be a tContextLoad. And then once the context is loaded I need to call another subjob to use that context. Then I need to repeat this step for each row in the tFileInputDelimited. That input file, by the way, would have the following structure (i.e. same context key, different values):
name=John
name=Carol
name=Joan
...
Please advise and if you have a snapshot of the flow that would help tremendously.

Re: Loop through input file to populate context variable to be used in job

Jcs19 — Thu, 09 Jul 2015 15:55:29 GMT

In the link you provided, if you look at some of the responses, Shong comes close to what I am looking for when he states the following:

You can use tFlowToIterate to iterate all rowss one by one, for example:
tFileInputDelimited--main(row1)-->tFlowToIterate--iterate--tRSSInput--main--tLogRow
on tRSSInput, set the RSS URL field as: row1.url

However, what I need in place of the tRSSInput would be a tContextLoad. And then once the context is loaded I need to call another subjob to use that context. Then I need to repeat this step for each row in the tFileInputDelimited. That input file, by the way, would have the following structure (i.e. same context key, different values):
name=John
name=Carol
name=Joan
...
Please advise and if you have a snapshot of the flow that would help tremendously.

I would replace tRSSInput by tJavarow and tLogRow by tRunJob (your child job)

Re: Loop through input file to populate context variable to be used in job

tale103108 — Fri, 10 Jul 2015 16:18:19 GMT

I figured this out by just using tJavaFlex in place of tRSSInput and adding some Java (see below)....

context.name = ((String)globalMap.get("row1.name"));
row2.name = context.name;

thanks for all your help.