# 500 errors from Webdev **URL:** \ **Category:** Ignition\ **Created:** [June 1, 2022, 4:00pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269 "2022-06-01T16:00:29Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 4:00pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/1 "2022-06-01T16:00:29Z")
Is there any other examples of using the servletRequest parameter in the Web Dev http methods? I am having the same issue with the 500 server error returning no matter if I return one of the required keys or return None. ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 1, 2022, 4:14pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/2 "2022-06-01T16:14:35Z")
That’s really not enough information to diagnose what’s happening. Start with checking your gateway’s logs to see what the actual 500 error is. ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 4:28pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/3 "2022-06-01T16:28:01Z")
It’s a Traceback error executing on a line in my code where I am using a system.db.runQuery such as this: testAnswer = system.db.runQuery(“INSERT INTO public.vin\_posts(vin\_data, dict\_data) VALUES(’{}’, ‘{}’)”.format(data, moreData), “eol\_post\_test”) It posts in my database just fine but I still get the error in the logs and Postman. ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 1, 2022, 4:32pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/4 "2022-06-01T16:32:28Z")
You should be using `runPrepQuery` for safe value substitution, but that’s a diversion. _What is the actual error being logged_? There will be a clear “this is what went wrong” exception being thrown, somewhere in the error. Post the full exception here, in a preformatted text block, and I can help you. Without that, I’m flying blind. ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 4:53pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/5 "2022-06-01T16:53:21Z")
```auto com.inductiveautomation.ignition.common.script.JythonExecException: Traceback (most recent call last): File "", line 6, in doPost at com.inductiveautomation.ignition.common.script.builtin.AbstractDBUtilities.error(AbstractDBUtilities.java:362) at com.inductiveautomation.ignition.common.script.builtin.AbstractDBUtilities.runQuery(AbstractDBUtilities.java:333) at jdk.internal.reflect.GeneratedMethodAccessor64.invoke(Unknown Source) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.base/java.lang.reflect.Method.invoke(Unknown Source) java.lang.Exception: java.lang.Exception: Error executing system.db.runQuery(INSERT INTO public.vin_posts(vin_data, dict_data) VALUES('5a2b173379', '{"lastName":"Blow","firstName":"5a2b173379","password":"abc123!@","role":"student","email":"under@gmail.com"}'), eol_post_test, ) at org.python.core.Py.JavaError(Py.java:547) at com.inductiveautomation.ignition.common.script.builtin.AbstractDBUtilities.error(AbstractDBUtilities.java:362) at com.inductiveautomation.ignition.common.script.builtin.AbstractDBUtilities.runQuery(AbstractDBUtilities.java:333) at jdk.internal.reflect.GeneratedMethodAccessor64.invoke(Unknown Source) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.base/java.lang.reflect.Method.invoke(Unknown Source) at org.python.core.PyReflectedFunction. __call__ (PyReflectedFunction.java:190) at com.inductiveautomation.ignition.common.script.ScriptManager$ReflectedInstanceFunction. __call__ (ScriptManager.java:541) at org.python.core.PyObject. __call__ (PyObject.java:477) at org.python.core.PyObject. __call__ (PyObject.java:481) at org.python.pycode._pyx28.doPost$1(:17) at org.python.pycode._pyx28.call_function() at org.python.core.PyTableCode.call(PyTableCode.java:173) at org.python.core.PyBaseCode.call(PyBaseCode.java:306) at org.python.core.PyFunction.function ___call__ (PyFunction.java:474) at org.python.core.PyFunction. __call__ (PyFunction.java:469) at org.python.core.PyFunction. __call__ (PyFunction.java:464) at com.inductiveautomation.ignition.common.script.ScriptManager.runFunction(ScriptManager.java:831) at com.inductiveautomation.ignition.common.script.ScriptManager.runFunction(ScriptManager.java:813) at com.inductiveautomation.ignition.gateway.project.ProjectScriptLifecycle$TrackingProjectScriptManager.runFunction(ProjectScriptLifecycle.java:806) at com.inductiveautomation.webdev.gateway.handlers.PythonResourceHandler.doRequest(PythonResourceHandler.java:294) at com.inductiveautomation.webdev.gateway.handlers.PythonResourceHandler.doPost(PythonResourceHandler.java:547) at com.inductiveautomation.webdev.gateway.servlets.WebDevDispatch.doPost(WebDevDispatch.java:153) at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) at com.inductiveautomation.webdev.gateway.servlets.WebDevDispatch.service(WebDevDispatch.java:118) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) at com.inductiveautomation.ignition.gateway.bootstrap.MapServlet.service(MapServlet.java:86) at org.eclipse.jetty.servlet.ServletHolder$NotAsync.service(ServletHolder.java:1450) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:799) at org.eclipse.jetty.servlet.ServletHandler$ChainEnd.doFilter(ServletHandler.java:1626) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:548) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:602) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:235) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1624) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1434) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:501) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1594) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1349) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) at com.inductiveautomation.catapult.handlers.RemoteHostNameLookupHandler.handle(RemoteHostNameLookupHandler.java:121) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) at org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:322) at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:59) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:146) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) at org.eclipse.jetty.server.Server.handle(Server.java:516) at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:388) at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:633) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:380) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:277) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105) at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:338) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:315) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:173) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:386) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:883) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1034) at java.base/java.lang.Thread.run(Unknown Source) Caused by: org.python.core.PyException: java.lang.Exception: java.lang.Exception: Error executing system.db.runQuery(INSERT INTO public.vin_posts(vin_data, dict_data) VALUES('5a2b173379', '{"lastName":"Blow","firstName":"5a2b173379","password":"abc123!@","role":"student","email":"under@gmail.com"}'), eol_post_test, ) ... 67 common frames omitted Caused by: java.lang.Exception: Error executing system.db.runQuery(INSERT INTO public.vin_posts(vin_data, dict_data) VALUES('5a2b173379', '{"lastName":"Blow","firstName":"5a2b173379","password":"abc123!@","role":"student","email":"under@gmail.com"}'), eol_post_test, ) ... 66 common frames omitted Caused by: org.postgresql.util.PSQLException: No results were returned by the query. at org.postgresql.jdbc.PgStatement.executeQuery(PgStatement.java:225) at org.apache.commons.dbcp2.DelegatingStatement.executeQuery(DelegatingStatement.java:329) at org.apache.commons.dbcp2.DelegatingStatement.executeQuery(DelegatingStatement.java:329) at com.inductiveautomation.ignition.gateway.datasource.DelegatingStatement.executeQuery(DelegatingStatement.java:64) at com.inductiveautomation.ignition.gateway.datasource.SRConnectionWrapper$SRStatement.executeQuery(SRConnectionWrapper.java:793) at com.inductiveautomation.ignition.gateway.datasource.SRConnectionWrapper.runQuery(SRConnectionWrapper.java:191) at com.inductiveautomation.ignition.gateway.script.GatewayDBUtilities._runQuery(GatewayDBUtilities.java:215) at com.inductiveautomation.ignition.common.script.builtin.AbstractDBUtilities.runQuery(AbstractDBUtilities.java:329) ... 64 common frames omitted ``` ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 5:03pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/6 "2022-06-01T17:03:09Z")
```auto jsonEntry = request['data'] if(len(jsonEntry) != 0): data = str(jsonEntry['firstName']) moreData = system.util.jsonEncode(jsonEntry) testAnswer = system.db.runQuery("INSERT INTO public.vin_posts(vin_data, dict_data) VALUES('{}', '{}')".format(data, moreData), "eol_post_test") #testAnswer = system.db.runPrepUpdate("INSERT INTO public.vin_posts (vin_data, dict_data) VALUES (?,?)", [data, moreData], "eol_post_test") else: testTwo = request['servletRequest'].inputStream() print(testTwo) e = system.utils.jsonEncode(testTwo) return {'json': e} # test = request['servletResponse'].outputStream() # print(test) # s = system.utils.jsonEncode(test) return {'json': jsonEntry} ``` ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 1, 2022, 5:19pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/7 "2022-06-01T17:19:34Z")
```nohighlight Caused by: org.postgresql.util.PSQLException: No results were returned by the query. ``` You’re running an UPDATE query via `runQuery`. JDBC (and thus the Postgres JDBC driver, which is what is ultimately throwing this exception) differentiate between queries and updates programmatically. You’ve got this line commented out: ```auto #testAnswer = system.db.runPrepUpdate("INSERT INTO public.vin_posts (vin_data, dict_data) VALUES (?,?)", [data, moreData], "eol_post_test") ``` That’s the right way to issue this. Was that giving you some issue? Running an update won’t give you a _response_ beyond the number of affected rows, but there’s no more information to get from an INSERT statement. ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 5:28pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/8 "2022-06-01T17:28:08Z")
I commented out the runPrepUpdate() because it wasn’t posting in the db for me. The runQuery() is the only one I can get to work for some reason. ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 1, 2022, 5:36pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/9 "2022-06-01T17:36:12Z")
Hm, `runPrepUpdate` is _definitely_ the right way to do this. `testAnswer` will be an integer on response. I’m not sure what output you’re looking for from the HTTP body. If you want to return the user details, perhaps issue a second query for the newly created user? Something like: ```python insertPost = "INSERT INTO public.vin_posts (vin_data, dict_data) VALUES (?,?)" key = system.db.runPrepUpdate(insertPost, [data, moreData], "eol_post_test", getKey=True) queryPost = "SELECT * FROM public.vin_posts WHERE id=?" createdRow = system.db.runPrepQuery(queryPost, [key], "eol_post_test") ``` ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 8:17pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/10 "2022-06-01T20:17:30Z")
Been trying different variations but runPrepQuery or runPrepUpdate doesn’t post at all in the db. The only progress I am getting is with the runQuery. ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 1, 2022, 8:22pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/11 "2022-06-01T20:22:54Z")
I can’t really fathom why that would be. If there’s e.g. a key constraint, then I would expect an error to be thrown. If you’re missing required info, an error should be thrown. There’s not very many ways for an INSERT to silently fail; it pretty much either works or it doesn’t. If you drop the `getKey` param and just log the return value, is the driver telling you you’ve updated one row in the DB? If you put the `gateway.database.updates` logger on TRACE you can see the actual query Ignition is executing, and you should also be able to see the incoming query in Postgres, somehow. ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 8:36pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/12 "2022-06-01T20:36:40Z")
![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/d/e/de661996e7b81e30d2887362f0c9739c2cd4eaec.png) ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 1, 2022, 8:40pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/13 "2022-06-01T20:40:43Z")
In the logs I do notice these false values in the queries. Does that have something to do with it? ---
**Author:** ![Richard\_Dixon](https://avatars.discourse-cdn.com/v4/letter/r/5e9695/32.png) [@Richard\_Dixon](https://forum.inductiveautomation.com/u/Richard_Dixon)\ **Post date:** [June 2, 2022, 1:24pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/14 "2022-06-02T13:24:01Z")
Good morning. I know I should be using the runPrep but since I feel pressured by time I will come back to that later. I am thinking this is a reason I am running into this 500 error and how can I use the servletResponse to send a proper status code to client? ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/5/e5e9f09277e27b34c9dc9e7ba4427dbd96d73a99.png) ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [June 2, 2022, 2:25pm UTC](https://forum.inductiveautomation.com/t/500-errors-from-webdev/60269/15 "2022-06-02T14:25:55Z")
The 500 error is being returned because the Python handler is throwing an exception. If you wrap your code that’s throwing in a try/catch (you may need to separately catch `java.lang.Exception`, for Jython compatibility reasons) then your endpoint should stop returning 500. You _can_ use `servletResponse` to set a specific response code, but it’s not generally required if a default 200 is fine. It would look something like this: `request['servletResponse'].status = 200` However, it’s probably not working because the exception thrown is engaging our handling, which will override any status you attempt to set. Which loops back to requiring you to catch the exception.