[GitHub] metron pull request #942: METRON-1461: Modify the MIN, MAX Stellar methods t...

[nickwallen]

Github user nickwallen commented on a diff in the pull request:

https://github.com/apache/metron/pull/942#discussion_r170597762
  
--- Diff: 
metron-stellar/stellar-common/src/main/java/org/apache/metron/stellar/dsl/functions/OrdinalFunctions.java
 ---
@@ -37,17 +35,23 @@
* Return the maximum value of a list of input values in a Stellar list
*/
   @Stellar(name = "MAX"
-  , description = "Returns the maximum value of a list of input 
values"
-  , params = {"list - List of arguments. The list may only contain 
objects that are mutually comparable / ordinal (implement java.lang.Comparable 
interface)" +
+  , description = "Returns the maximum value of a list of input 
values or from a statistics object"
+  , params = {"stats - The Stellar statistics object"
+  ,"list - List of arguments. The list may only contain objects 
that are mutually comparable / ordinal (implement java.lang.Comparable 
interface)" +
   " Multi type numeric comparisons are supported: 
MAX([10,15L,15.3]) would return 15.3, but MAX(['23',25]) will fail and return 
null as strings and numbers can't be compared."}
-  , returns = "The maximum value in the list, or null if the list 
is empty or the input values were not comparable.")
+  , returns = "The maximum value in the list or from stats, or 
null if the list is empty or the input values were not comparable.")
   public static class Max extends BaseStellarFunction {
 
 @Override
 public Object apply(List args) {
   if (args.size() < 1 || args.get(0) == null) {
 throw new IllegalStateException("MAX function requires at least a 
Stellar list of values");
   }
+  Object firstArg = args.get(0);
+  if(firstArg instanceof Ordinal) {
+Ordinal stats = convert(firstArg, Ordinal.class);
+return stats.getMax();
+  }
   Iterable list = (Iterable) args.get(0);
--- End diff --

It would make sense to wrap the existing "iterable" handling code in an 
"else if".  And also handle the possibility that the argument is not an 
Iterable nor an Ordinal. Perhaps like so...

```
Object firstArg = args.get(0);
if(firstArg instanceof Ordinal) {
  

} else if(firstArg instanceof Iterable) {
  

} else {
   throw new IllegalStateException("MAX function expects either  ");

}
```


---

[GitHub] metron pull request #942: METRON-1461: Modify the MIN, MAX Stellar methods t...

[nickwallen]

Github user nickwallen commented on a diff in the pull request:

https://github.com/apache/metron/pull/942#discussion_r170595688
  
--- Diff: 
metron-stellar/stellar-common/src/main/java/org/apache/metron/stellar/dsl/functions/OrdinalFunctions.java
 ---
@@ -37,17 +35,23 @@
* Return the maximum value of a list of input values in a Stellar list
*/
   @Stellar(name = "MAX"
-  , description = "Returns the maximum value of a list of input 
values"
-  , params = {"list - List of arguments. The list may only contain 
objects that are mutually comparable / ordinal (implement java.lang.Comparable 
interface)" +
+  , description = "Returns the maximum value of a list of input 
values or from a statistics object"
+  , params = {"stats - The Stellar statistics object"
+  ,"list - List of arguments. The list may only contain objects 
that are mutually comparable / ordinal (implement java.lang.Comparable 
interface)" +
   " Multi type numeric comparisons are supported: 
MAX([10,15L,15.3]) would return 15.3, but MAX(['23',25]) will fail and return 
null as strings and numbers can't be compared."}
-  , returns = "The maximum value in the list, or null if the list 
is empty or the input values were not comparable.")
+  , returns = "The maximum value in the list or from stats, or 
null if the list is empty or the input values were not comparable.")
   public static class Max extends BaseStellarFunction {
 
 @Override
 public Object apply(List args) {
   if (args.size() < 1 || args.get(0) == null) {
 throw new IllegalStateException("MAX function requires at least a 
Stellar list of values");
--- End diff --

With your changes, this error message is now incorrect.  Can you update 
this? 

This only checks the number of args, so the error message should probably 
just say that we expect one argument or something to that effect.


---

[GitHub] metron pull request #942: METRON-1461: Modify the MIN, MAX Stellar methods t...

[nickwallen]

Github user nickwallen commented on a diff in the pull request:

https://github.com/apache/metron/pull/942#discussion_r170598354
  
--- Diff: 
metron-stellar/stellar-common/src/main/java/org/apache/metron/stellar/dsl/functions/Ordinal.java
 ---
@@ -0,0 +1,24 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.metron.stellar.dsl.functions;
+
+public interface Ordinal {
--- End diff --

Can you add javadocs for the class and each method?


---

[GitHub] metron pull request #942: METRON-1461: Modify the MIN, MAX Stellar methods t...

[MohanDV]

GitHub user MohanDV opened a pull request:

https://github.com/apache/metron/pull/942

METRON-1461: Modify the MIN, MAX Stellar methods to take a stats or list 
object and return min and max


## Contributor Comments
Presently the MIN and MAX stellar function accepts only the list  as input 
and the list may only contain objects that are mutually comparable / ordinal. 
Modify the method to take a stats or list object and return min/max.

## Pull Request Checklist

Thank you for submitting a contribution to Apache Metron.  
Please refer to our [Development 
Guidelines](https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=61332235)
 for the complete guide to follow for contributions.  
Please refer also to our [Build Verification 
Guidelines](https://cwiki.apache.org/confluence/display/METRON/Verifying+Builds?show-miniview)
 for complete smoke testing guides.  


In order to streamline the review of the contribution we ask you follow 
these guidelines and ask you to double check the following:

### For all changes:
- [x] Is there a JIRA ticket associated with this PR? If not one needs to 
be created at [Metron 
Jira](https://issues.apache.org/jira/browse/METRON/?selectedTab=com.atlassian.jira.jira-projects-plugin:summary-panel).
- [x] Does your PR title start with METRON- where  is the JIRA 
number you are trying to resolve? Pay particular attention to the hyphen "-" 
character.
- [x] Has your PR been rebased against the latest commit within the target 
branch (typically master)?


### For code changes:
- [ ] Have you included steps to reproduce the behavior or problem that is 
being changed or addressed?
- [ ] Have you included steps or a guide to how the change may be verified 
and tested manually?
- [ ] Have you ensured that the full suite of tests and checks have been 
executed in the root metron folder via:
  ```
  mvn -q clean integration-test install && 
dev-utilities/build-utils/verify_licenses.sh 
  ```

- [x] Have you written or updated unit tests and or integration tests to 
verify your changes?
- [ ] If adding new dependencies to the code, are these dependencies 
licensed in a way that is compatible for inclusion under [ASF 
2.0](http://www.apache.org/legal/resolved.html#category-a)?
- [ ] Have you verified the basic functionality of the build by building 
and running locally with Vagrant full-dev environment or the equivalent?

### For documentation related changes:
- [ ] Have you ensured that format looks appropriate for the output in 
which it is rendered by building and verifying the site-book? If not then run 
the following commands and the verify changes via 
`site-book/target/site/index.html`:

  ```
  cd site-book
  mvn site
  ```

 Note:
Please ensure that once the PR is submitted, you check travis-ci for build 
issues and submit an update to your PR as soon as possible.
It is also recommended that [travis-ci](https://travis-ci.org) is set up 
for your personal repository such that your branches are built there before 
submitting a pull request.


You can merge this pull request into a Git repository by running:

$ git pull https://github.com/MohanDV/metron METRON-1461

Alternatively you can review and apply these changes as the patch at:

https://github.com/apache/metron/pull/942.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

This closes #942


commit 5cb3a9354efbba6c8f9b85382848152839407d68
Author: Mohan Venkateshaiah 
Date:   2018-02-23T19:59:07Z

Modify the MIN, MAX Stellar methods to take a stats or list object and 
return min/max.




---