I wasn’t expecting this week to be so “productive” 🙂
I had the chance to engage again with Documentum support, which is always an adventure 😉
We’re currently porting a framework from DFS to REST services. A couple of days ago, one of my colleagues had a problem and ask me if I knew why a query through the REST services was failing.
The query is using DATETOSTRING to retrieve a time field and returning a column with the attribute name using the alias, so, if a user requests expiration_date we execute a query like:
select DATETOSTRING(expiration_date,’dd/mm/yyyy’) as expiration_date from…
which returns the requested attribute in the desired (configurable) format. Easy, right? Well, the problem was that using r_creation_date or r_modify_date was throwing an exception:
 {   “status”: 400,
“code”: “E_INPUT_ILLEGAL_ARGUMENTS”,
“message”: “There are illegal arguments provided.”,
“details”: “Invalid format: \”12/04/2013\” is malformed at \”/04/2013\””}
We also observed that changing the alias to something else than r_creation_date/r_modify_date would work (but it was breaking our use case).
This was weird, because I was quite sure that those kind of queries worked previously, so I checked against the Content Server:
Connected to Documentum Server running Release 7.1.0210.0328Â Linux64.Oracle
1> select DATETOSTRING(r_creation_date,’dd/mm/yyyy’) as r_creation_date from dm_document enable (return_top 1);
2> go
r_creation_date
—————
12/04/2013
(1 row affected)
As I though, it was working just fine. I suspected it had something to do with the custom date format, as EMC/OpenText tends to forget that not everyone uses ANSI or the american date format, so I decided to open a SR.
After some exchange of emails, we were told that both r_creation_date and r_modify_date where reserved words and that it was expected to fail. What???
After asking support to either fill this as a product limitation or fixing it, I decided to take a look at the code myself.
As I suspected, the query works just fine, and results are returned to the Query controller. The problem here is with the way REST generates the response. If you run the query with a different alias to see the result page you’ll get this:
"entries": [Â {
"id": "http://127.0.0.1:8080/dctm-rest/repositories/repo.json?dql=select%20DATETOSTRING_LOCAL(r_creation_date,%27dd/mm/yyyy%27)%20as%20rr_creation_date%20from%20dm_document%20enable%20(return_top%201)&index=0",
"title": "12/04/2013",
"updated": "2017-06-16T11:04:38.284+00:00",
"published": "2017-06-16T11:04:38.284+00:00",
"content": {
"json-root": "query-result",
"definition": "http://127.0.0.1:8080/dctm-rest/repositories/repo/types/dm_document.json",
"properties": {
"rr_creation_date": "12/04/2013"
}}}]
Do you see those fields before the content element? That’s where everything breaks, why? Because of this:
public Date entryUpdated() {
Date updated = null;
Object modifyDate = ((QueryResultItem)getDataInternal())
.getMandatoryAttribute("r_modify_date");
if (modifyDate == null) {
updated = new Date();
} else if ((modifyDate instanceof Date)) {
updated = (Date)modifyDate;
} else {
updated = DateFormatter.parse(modifyDate.toString());
}
return updated;
}
public Date entryPublished()
{
Date published = null;
QueryResultItem queryResultItem=getDataInternal();
Object modifyDate = ((QueryResultItem)getDataInternal())
.getMandatoryAttribute("r_creation_date");
if (modifyDate == null) {
published = new Date();
} else if ((modifyDate instanceof Date)) {
published = (Date)modifyDate;
} else {
published = DateFormatter.parse(modifyDate.toString());
}
return published;
}
As you can see (besides the obvious copy/paste from one method to another changing the name of one variable), the standard view looks in the results from the query for a column with those names, and if it founds a column matching that name, tries to parse it with a forced format (which of course, it’s miserably failing with our custom date format).
This, in my opinion, is a bug, because the behaviour of the query functionality it is inconsistent between the Documentum stack, in fact, this query only fails with REST services, so I’ll keep pushing the SR to be treated as a bug and fixed by the talented team, and not as a “product limitation” or a “feature request”.
And if you face the same problem, and it is still not fixed, you have three options:
- Keep waiting for a fix
- Extend com.emc.documentum.rest.view.impl.QueryResultItemView and handle the IllegalArgumentException that throws DateFormatter.parse
- Extend the controller adding a custom view for the results and removing/overriding the updated/published fields.
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