Develop Reference

Firestore - Use update method for document but with Object (Java)

I want to update a document with a User object that I have, but I do not want the document to be created if it does not exist, and therefore I cannot use "DocumentReference.set" with "SetOptions.Merge()" (to my understanding).
However, according to this post (Difference between set with {merge: true} and update), "update" is actually the command I need. My problem is, it doesn't seem like update accepts a Java object.
I do not want to check whether or not the document exists myself, as this will result in an unnecessary read.
Is there any way around this?
Here is my code (I have removed success and failure listeners for simplicity):
public void saveUser(User user)
{
CollectionReference collection = db.collection("users");
String id = user.getId();
if (id.equals(""))
{
collection.add(user);
}
else
{
// I need to ensure that the ID variable for my user corresponds
// with an existing ID, as I do not want a new ID to be generated by
// my Java code (all IDs should be generated by Firestore auto-ID)
collection.document(ID).set(user);
}
}

It sounds like you:
Want to update an existing document
Are unsure if it already exists
Are unwilling to read the document to see if it exists
If this is the case, simply call update() and let it fail if the document doesn't exist. It won't crash your app. Simply attach an error listener to the task it returns, and decide what you want to do if it fails.
However you will need to construct a Map of fields and values to update using the source object you have. There are no workarounds for that.

Enumerate Custom Slot Values from Speechlet

Is there any way to inspect or enumerate the Custom Slot Values that are set-up in your interaction model? For Instance, Say you have an intent schema with the following intent:
{
"intent": "MySuperCoolIntent",
"slots":
[
{
"name": "ShapesNSuch",
"type": "LIST_OF_SHAPES"
}
]
}
Furthermore, you've defined the LIST_OF_SHAPES Custom Slot to have the following Values:
SQUARE
TRIANGLE
CIRCLE
ICOSADECAHECKASPECKAHEDRON
ROUND
HUSKY
Question: is there a method I can call from my Speechlet or my RequestStreamHandler that will give me an enumeration of those Custom Slot Values??
I have looked through the Alexa Skills Kit's SDK Javadocs Located Here
And I'm not finding anything.
I know I can get the Slot's value that is sent in with the intent:
String slotValue = incomingIntentRequest.getIntent().getSlot("LIST_OF_SHAPES").getValue();
I can even enumerate ALL the incoming Slots (and with it their values):
Map<String, Slot> slotMap = IncomingIntentRequest.getIntent().getSlots();
for(Map.Entry<String, Slot> entry : slotMap.entrySet())
{
String key = entry.getKey();
Slot slot = (Slot)entry.getValue();
String slotName = slot.getName();
String slotValue = slot.getValue();
//do something nifty with the current slot info....
}
What I would really like is something like:
String myAppId = "amzn1.echo-sdk-ams.app.<TheRestOfMyID>";
List<String> posibleSlotValues = SomeMagicAlexaAPI.getAllSlotValues(myAppId, "LIST_OF_SHAPES");
With this information I wouldn't have to maintain two separate "Lists" or "Enumerations"; One within the interaction Model and another one within my Request Handler. Seems like this should be a thing right?

No, the API does not allow you to do this.
However, since your interaction model is intimately tied with your development, I would suggest you check in the model with your source code in your source control system. If you are going to do that, you might as well put it with your source. Depending on your language, that also means you can probably read it during run-time.
Using this technique, you can gain access to your interaction model at run-time. Instead of doing it automatically through an API, you do it by best practice.
You can see several examples of this in action for Java in TsaTsaTzu's examples.

No - there is nothing in the API that allows you to do that.
You can see the full extent of the Request Body structure Alexa gives you to work with. It is very simple and available here:
https://developer.amazon.com/public/solutions/alexa/alexa-skills-kit/docs/alexa-skills-kit-interface-reference#Request%20Format
Please note, the Request Body is not to be confused with the request, which is a structure in the request body, with two siblings: version and session.

Handling non-fatal errors in Java

I've written a program to aid the user in configuring 'mechs for a game. I'm dealing with loading the user's saved data. This data can (and some times does) become partially corrupt (either due to bugs on my side or due to changes in the game data/rules from upstream).
I need to be able to handle this corruption and load as much as possible. To be more specific, the contents of the save file are syntactically correct but semantically corrupt. I can safely parse the file and drop whatever entries that are not semantically OK.
Currently my data parser will just show a modal dialog with an appropriate warning message. However displaying the warning is not the job of the parser and I'm looking for a way of passing this information to the caller.
Some code to show approximately what is going on (in reality there is a bit more going on than this, but this highlights the problem):
class Parser{
public void parse(XMLNode aNode){
...
if(corrupted) {
JOptionPane.showMessageDialog(null, "Corrupted data found",
"error!", JOptionPane.WARNING_MESSAGE);
// Keep calm and carry on
}
}
}
class UserData{
static UserData loadFromFile(File aFile){
UserData data = new UserData();
Parser parser = new Parser();
XMLDoc doc = fromXml(aFile);
for(XMLNode entry : doc.allEntries()){
data.append(parser.parse(entry));
}
return data;
}
}
The thing here is that bar an IOException or a syntax error in the XML, loadFromFile will always succeed in loading something and this is the wanted behavior. Somehow I just need to pass the information of what (if anything) went wrong to the caller. I could return a Pair<UserData,String> but this doesn't look very pretty. Throwing an exception will not work in this case obviously.
Does any one have any ideas on how to solve this?

Depending on what you are trying to represent, you can use a class, like SQLWarning from the java.sql package. When you have a java.sql.Statement and call executeQuery you get a java.sql.ResultSet and you can then call getWarnings on the result set directly, or even on the statement itself.
You can use an enum, like RefUpdate.Result, from the JGit project. When you have a org.eclipse.jgit.api.Git you can create a FetchCommand, which will provide you with a FetchResult, which will provide you with a collection of TrackingRefUpdates, which will each contain a RefUpdate.Result enum, which can be one of:
FAST_FORWARD
FORCED
IO_FAILURE
LOCK_FAILURE
NEW
NO_CHANGE
NOT_ATTEMPTED
REJECTED
REJECTED_CURRENT_BRANCH
RENAMED
In your case, you could even use a boolean flag:
class UserData {
public boolean isCorrupt();
}
But since you mentioned there is a bit more than that going on in reality, it really depends on your model of "corrupt". However, you will probably have more options if you have a UserDataReader that you can instantiate, instead of a static utility method.

PHP how to consume SOAP web services?

I'm very new in using web services. Appreciate if anyone can help me on this.
In my PHP codes, I'm trying to use the SOAP web services from another server (JIRA, java). The JIRA SOAP API is shown here.
$jirasoap = new SoapClient($jiraserver['url']);
$token = $jirasoap->login($jiraserver['username'], $jiraserver['password']);
$remoteissue = $jirasoap->getIssue($token, "issuekey");
I found that my codes have no problem to call the functions listed on that page. However, I don't know how to use the objects returned by the API calls.
My question are:
In my PHP codes, how can I use the methods in the Java class objects returned by SOAP API calls?
For example, the function $remoteissue = $jirasoap->getIssue($a, $b) will return a RemoteIssue. Based on this (http://docs.atlassian.com/rpc-jira-plugin/latest/com/atlassian/jira/rpc/soap/beans/RemoteIssue.html), there are methods like getSummary, getKey, etc. How can I use these functions in my codes?
Based on some PHP examples I found from the internet, it seems that everyone is using something like this:
$remoteissue = $jirasoap->getIssue($token, "issuekey");
$key = $remoteissue->key;
They are not using the object's methods.
Refer to this example, it seems that someone is able to do this in other languages. Can it be done in PHP too?
The problem I'm facing is that, I am trying to get the ID of an Attachment. However, it seems that we can't get the Attachment ID using this method: $attachmentid = $remoteattachment->id;. I am trying to use the $remoteattachment->getId() method.
In PHP codes, after we made a SOAP API call and received the returned objects, how do we know what data fields are available in that object?
For example,
$remoteissue = $jirasoap->getIssue($token, "issuekey");
$summary = $remoteissue->summary;
How do we know ->summary is available in $remoteissue?
When i refer to this document (http://docs.atlassian.com/rpc-jira-plugin/latest/com/atlassian/jira/rpc/soap/beans/RemoteIssue.html), I don't see it mention any data fields in RemoteIssue. How do we know we can get key, summary, etc, from this object? How do we know it is ->summary, not ->getsummary? We need to use a web browser to open the WSDL URL?
Thanks.

This question is over one year old, but to share knowledge and provide an answer to people who have this same question and found this page, here are my findings.
The document mentioned in the question is an overview of the JiraSoapService interface. This is a good reference for what functions can be called with which arguments and what they return.
If you use Java for your Jira SoapClient the returned objects are implemented, but if you use PHP, the returned objects aren't of the type stated in this documentation and do not have any of the methods mentioned. The returned objects are instances of the internal PHP class stdClass, which is a placeholder for undefined objects. The best way to know what is returned is to use var_dump() on the objects returned from the SoapCalls.
$jirasoap = new SoapClient($jiraserver['url']);
$token = $jirasoap->login($jiraserver['username'], $jiraserver['password']);
$remoteissue = $jirasoap->getIssue($token, "PROJ-1");
var_dump($remoteissue);
/* -- You will get something like this ---
object(stdClass)#2 (21) {
["id"]=> string(3) "100"
["affectsVersions"]=> array(0) { }
["assignee"]=> string(4) "user"
...
["created"]=> string(24) "2012-12-13T09:27:49.934Z"
...
["description"]=> string(17) "issue description"
....
["key"]=> string(6) "PROJ-1"
["priority"]=> string(1) "3"
["project"]=> string(4) "PROJ"
["reporter"]=> string(4) "user"
["resolution"]=> NULL
["status"]=> string(1) "1"
["summary"]=> string(15) "Project issue 1"
["type"]=> string(1) "3"
["updated"]=> string(24) "2013-01-21T16:11:43.073Z"
["votes"]=> int(0)
}
*/
// You can access data like this:
$jiraKey = $remoteissue->key;
$jiraProject = $remoteissue->project;

The document you referred to in #2 is to a Java implementation and really doesn't give you any help with PHP. If they do not publish a public API for their service (which would be unusual), then using the WSDL as a reference will let you know what objects and methods are accepted by the service and you can plan your method calls accordingly.
The technique you used to call getIssue(...) seems fine, although you should consider using try...catch in case of a SoapException.

I have used Jira SOAP in .NET project and IntelliSense hinted me what fields are available for returned object.
You can use something like VS.Php for Visual Studio or Php for Visual Studio if you are using Visual Studio.
Or you can choose one of the IDEs from here with support of IntelliSense.

If my Ehcache is configured with a TTL, do I need to check if a retrieved Element is expired?

I can't find this anywhere in the Ehcache docs.
Right now I'm using this code to create and configure my Cache:
// Groovy syntax
def cacheConfig = new CacheConfiguration('stats', 1)
cacheConfig.timeToLiveSeconds = 2
def cache = new Cache(cacheConfig)
cache.initialise()
and this to retrieve data:
// Groovy syntax
def cachedElement = cache.get('stats')
if (cachedElement != null && ! cachedElement.isExpired()) {
// use the cached data
} else {
// get/generate the data and cache it
}
return cachedElement.value
I wrote this awhile ago, but looking at it now it seems kinda silly to have to check Element.isExpired() — that shouldn't be necessary, right? I mean, if an element is expired, then the cache shouldn't return it — right?
So I'm thinking I can remove that check — just hoping for a quick sanity check here.
Thanks!

No, you don't have to perform this check. If you get a non-null element back, then it's not expired. It is odd that the javadoc doesn't mention this, right enough, and although I have read this somewhere, I can't find a reference to back up my answer.

If it is possible that your cacheElement could actually be null then the null check is not enough. Simply returning null when something is expired is not always sufficient in that case. Ecache has no reliable way of determining if something is expired until it is accessed. You could set the following in the config:
<ehcache:config cache-manager="ehCacheManager">
<!-- interval is in minutes -->
<ehcache:evict-expired-elements interval="20"/>
</ehcache:config>
but there is always a chance that your access will fall within that interval.
If you are absolutly certain that your values are never null, then you can drop the isExpired() call.