Recently i've been working on an application which allow the users to query enities from a ContextBroker , Cosmos and so on . One feature of the application is to initialize an entity which will be used by a connected object to store data .
The creation works fine , but I have a little problem .
As said in the documentation for the Orion ContextBroker , when an Entity already exists the APPEND action is interpreted as a UPDATE (I sincerely don't understand why) . So here's a scenario , the user have a Entity called Room1 , the sensors give him his data and stores it . One day , he want to create a new entity , but make an error and call it Room1 . All the current data from Room1 will be reset to the default value I put in my application .
Here is my question , is there a way to check if the entity already exist other than doing a manual query (which will take a much longer time to process) in the application before the creation ?
Thank you for reading my question and have a good day .
Guillaume Jourdain .
Currently (Orion 0.22.0), the only way is the one you mention: check that the entity already exist doing a query.
The reason to implement update in this way is that for many uses cases, the desired behavious is exactly the oposites: the client doen't want to get an error if the entity previously doesn't exist and the "append or update" semantics works fine. Unfortunatelly, making happy one use case makes sad the other :(
The best solution would be making this behaviour configurable. We are now defining a new version of the FIWARE NGSI API that Orion implements, including a URL option to set the behaviour, e.g. ?options=append to set "strict append" semantics (opossite to "append or update" semantics).
EDIT: Orion 0.24.0 introduces the APPEND_STRICT action, which returns an error if the attribute to add already exists.
Related
I was solving one of TryHackMe's rooms about SQL injection.But I couldn't figured out one thing that came to my mind and after spending lots of time I thought it's best to ask that question here. In the room there is a machine to deploy, after deployed machine it gave me an interface(webapp) that takes inputs from me like so :
And if you give it a value like test. It returns following output:
When I saw it, I thought it was an easy SQLi question so I tried most basic SQLi payloads for common dbms like so:
' ; sleep(1) --
' or 1=1 -- ...
But none of them worked and returned me an error message like that:
After that failure, I run sqlmap and it found 2 types of SQLi payload with following payloads:
Then I realized that in time based SQLi, sqlmap used ||. Then I tried to send '|| (select sleep(2)) -- . And it worked. Now my question is why my first payload(' ; select sleep(2) -- ) didn't work, but this one worked ?
By default, MySQL query interfaces do not support multiple queries separated by semicolon. To get that, the application would have to explicitly request this feature to be enabled when it connects to the database. There's a connect option for that.
So by default, any type of SQL injection that works by trying to append a malicious query after a semicolon doesn't work.
But an SQL injection that works by modifying an expression in the single query can still work.
I have been getting this annoying exception while trying to create a native query with my entity manager. The full error message is:
java.lang.IllegalStateException: During synchronization a new object was found through a relationship that was not marked cascade PERSIST: com.model.OneToManyEntity2#61f3b3b.
at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.discoverUnregisteredNewObjects(RepeatableWriteUnitOfWork.java:313)
at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.calculateChanges(UnitOfWorkImpl.java:723)
at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.writeChanges(RepeatableWriteUnitOfWork.java:441)
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.flush(EntityManagerImpl.java:874)
at org.eclipse.persistence.internal.jpa.QueryImpl.performPreQueryFlush(QueryImpl.java:967)
at org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:207)
at org.eclipse.persistence.internal.jpa.QueryImpl.getSingleResult(QueryImpl.java:521)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getSingleResult(EJBQueryImpl.java:400)
The actual code that triggers the error is:
Query query;
query = entityManager.createNativeQuery(
"SELECT MAX(CAST(SUBSTRING_INDEX(RecordID,'-',-1) as Decimal)) FROM `QueriedEntityTable`");
String recordID = (query.getSingleResult() == null ?
null :
query.getSingleResult()
.toString());
This is being executed with an EntityTransaction in the doTransaction part. The part that is getting me with this though is that this is the first code to be executed within the doTransaction method, simplified below to:
updateOneToManyEntity1();
updateOneToManyEntity2();
entityManager.merge(parentEntity);
The entity it has a problem with "OneToManyEntity1" isn't even the table I'm trying to create the query on. I'm not doing any persist or merge up until this point either, so I'm also not sure what is supposedly causing it to be out of sync. The only database work that's being done up until this code is executed is just pulling in data, not changing anything. The foreign keys are properly set up in the database.
I'm able to get rid of this error by doing as it says and marking these relationships as Cascade.PERSIST, but then I get a MySQLContrainstraViolationException on the query.getSingleResult() line. My logs show that its doing some INSERT queries right before this, so it looks like its reaching the EntityManager.merge part of my doTransaction method, but the error and call stack point to a completely different part of the code.
Using EclipseLink (2.6.1), Glassfish 4, and MySQL. The entitymanager is using RESOURCE_LOCAL with all the necessary classes listed under the persistence-unit tag and exclude-unlisted-classes is set to false.
Edit: So some more info as I'm trying to work through this. If I put a breakpoint at the beginning of the transaction and then execute entityManager.clear() through IntelliJ's "Evaluate Expression" tool, everything works fine at least the first time through. Without it, I get an error as it tries to insert empty objects into the table.
Edit #2: I converted the nativeQuery part into using the Criteria API and this let me actually make it through my code so I could find where it was unintentionally adding in a null object to my entity list. I'm still just confused as to why the entity manager is caching these errors or something to the point that creating a native query is breaking because its still trying to insert bad data. Is this something I'd need to call EntityManager.clear() before doing each time? Or am I supposed to call this when there is an error in the doTransaction method?
So after reworking the code and setting this aside, I stumbled on at least part of the answer to my question. My issue was caused by the object being persisted prior to the transaction starting. So when I was entering my transaction, it first tried to insert/update data from my entity objects and threw an error since I hadn't set the values of most of the non-null columns. I believe this is the reason I was getting the cascade errors and I'm positive this is the source of the random insert queries I saw being fired off at the beginning of my transaction. Hope this helps someone else avoid a lot of trouble.
I'm new to the whole pimcore thing. I am trying to play around and create classes. The issue is, I am not able to create more than 1 class, and in the database it is nameless, so when I try to create another class, it also tries to store it in the database with no name, which ends up showing an SQL error saying that there is a duplicate entry. Any ideas what the reason behind this could be?
I installed pimcore on an nginx server, I am trying to create classes by choosing Settings->Objects->Classes and then "Add Class", creating the first class was ok, I entered a name for the class and it was successfully added, however the name field in the corresponding database entry is empty, as in empty string ' '. So, when I try to add another class and pimcore attempts to store it in the table "classes", it returns an error saying that it would be a duplicate entry since they both are nameless, i.e. the name entered isn't added. The following error is what I managed to find using developer tools, could be helpful.
[WARN] Unable to parse the JSON returned by the server
minified_javascript_core_f5757da….js?_dc=3708:5684 Error: You're trying to decode an invalid JSON String:
Fatal error: Call to a member function hasChilds() on null in /var/www/html/pimproject/pimcore/modules/admin/controllers/DocumentController.php on line 59
at new Ext.Error (http://192.10.0.0/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:27054)
at Function.Ext.apply.raise (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:27447)
at Object.Ext.raise (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:27594)
at Object.Ext.JSON.me.decode (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:385102)
at Ext.define.onProxyLoad (http://192.10.0.10/website/var/tmp/minified_javascript_core_f5757da9fa29d5bf13e6aa5058eff9f7.js?_dc=3708:5641:28)
at Ext.cmd.derive.triggerCallbacks (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:594533)
at Ext.cmd.derive.setCompleted (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:594231)
at Ext.cmd.derive.setException (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:594444)
at Ext.cmd.derive.process (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:593638)
at Ext.cmd.derive.processResponse (http://192.10.0.10/pimcore/static6/js/lib/ext/ext-all.js?_dc=3708:22:648303)
Just reinstall Pimcore.
It can be some composer or submodules error.
I strongly recommend for the first installation to run Demo project https://github.com/pimcore/demo not Skeleton, especially if you are using Docker. Later, when you will get the feeling of Pimcore, feel free to install Skeleton or any other project.
Pimcore is stable working for years. If you had some problems before -- nowadays, it is stable.
I recently developed a Java client which allow me to query my Hive tables from a simple url .
Unfortunately , since last Thursday the queries seems to have some issues . From time to time , my query which worked before , doesn't return me anything .
So I decided to take a look at my logs, and everytime I do a query this occur :
java.sql.SQLException: Query returned non-zero code: 12, cause: FAILED: Hive Internal Error: java.lang.RuntimeExcep
tion(org.apache.hadoop.ipc.RemoteException: org.apache.hadoop.hdfs.server.namenode.SafeModeException: Cannot create
directory /tmp/hive-root/hive_2015-06-29_09-19-53_268_7855618362212093455. Name node is in safe mode.
Resources are low on NN. Safe mode must be turned off manually.
I think the issue come from the node itself , because I didn't do any changes on my code or in my hive tables . What do you think the problem come from ? And what can I do to resolve it ?
Thank you for your reading my question .
This was due the cluster automatically entered in safe mode. We fixed it by freeing/adding some disk space.
You might read this question every day so i tried another Stackoverflow's answer before asking:
CakePHP table is missing even when it exists
Anyways. The table i try to select data from does exist (quadra-checked uppercase/lowercase!) and it gets also listed via $db->->listSources().
Here's a screenshot of the query, the message and the last result from listing all Datasource's tables:
http://i.stack.imgur.com/CdhcV.png
Note: If i run this query in PHPMyAdmin manually it works fine. I would say its impossible to get the pictures output at one time in a view - now its up to you to tell me the opposite. By the way: I am pretty sure to use the correct Datasource.
I should tell additionally that the mysql-server is hosted on another platform. Since i can use it for my localhost-phpmyadmin if i modify the config.inc.php i can promise it is no Firewall-Problem.
Written in behalf of xcy7e:
The mistake was to execute the Query from the local Model. Here's the code:
$conn = ConnectionManager::getDataSource('myDB');
$conn->query($query);
// instead of $this->query($query);