GHNP call in IMS DB - cobol

I would like to know what calls in IMS need to be made before going for GHNP call. My application cobol code has GU, GHU calls before going for GHNP call. Is it mandatory to have those calls before going for GHNP function

Note that GN means "get next", so all GN-type calls (GN,GNP,GHN,GHNP) depend on your current position in the database. Without any previous calls the position is undefined and so would be the result of your GN-call.
So to get a well defined result you have to issue a statement to establish a well-defined position in your database - and usually this is a GU-Type ("get unique") call. It can also be an ISRT ("insert") as this results in a defined position as well. But usually your application-logic should show you the way to go.

Related

Using data movement sdk ,want to remove collection from docs in real time in marklogic?

Actually I am new to data movement SDK,I want to know how we can used data movement sdk to remove collection from docs which match's specific condition in real time in marklogic ?
Yes, DMSK can reprocess documents in the database including modifying the collections on the documents.
The most efficient way to change document collections on the server might be to take an approach similar to the out-of-the-box ApplyTransformListener (as summarized by
https://docs.marklogic.com/guide/java/data-movement#id_51555) but to execute a custom module instead of a transform.
Summarizing the main points:
Write an SJS (Server-Side JavaScript) module that declares a variable (using the JavaScript var statement) to receive the document URIs sent by the client and modifies the collections on those documents using a function such as
https://docs.marklogic.com/xdmp.documentSetCollections
Install the SJS module in the modules database as described here
https://docs.marklogic.com/guide/java/resourceservices#id_13008
Create a QueryBatcher to get the document URIs either from a query on the database or from a client iterator as described here:
https://docs.marklogic.com/guide/java/data-movement#id_46947
Supply a lambda function for the QueryBatcher.onUrisReady() method - see
https://docs.marklogic.com/javadoc/client/com/marklogic/client/datamovement/QueryBatcher.html#onUrisReady-com.marklogic.client.datamovement.QueryBatchListener-
In the lambda function, construct and execute a ServerEvaluationCall to the SJS module, assigning the variable to the URIs passed to the lambda function - see:
https://docs.marklogic.com/guide/java/resourceservices#id_84134
Be sure to register failure listeners using the QueryBatcher.onQueryFailure() ApplyTransformListener.onFailure​() methods to log error or otherwise respond to the unexpected.
Hoping that helps,

Umbraco7 - ContentService.SaveAndPublishWithStatus VS ContentService.SendToPublication

I have an application that uses a combination of ContentService.Saved & ContentService.Saving to extend Umbraco to manage content.
I have two websites in one Umbraco installation I am using those methods to keep content up to date in different parts of the tree.
So far I have got everything working the way I wanted to.
Now I want to add a feature that: depending on which Umbraco User is logged in, will either publish the content or simply send it for approval.
So I have changed some lines of code from:
cs.SaveAndPublishWithStatus(savedNode, 0, false)
To this:
cs.SendToPublication(savedNode);
Now the problem that I am finding is that unlike the SaveAndPublishWithStatus() method, the cs.SendToPublication(); doesn't have the option of passing false so that a save event is not raised. So I get into an infinite loop.
When I attach the debugger and manually stop the infinite loop the first time it calls cs.SendToPublication(savedNode); I get exactly the behavior I want.
Any ideas about how I can get round this problem? Is there a different method that I should be using?
You are correct in saying that it currently isn't possible to set raiseEvents to false when sending an item to publication - that's a problem.
I've added that overload in v. 7.6 (http://issues.umbraco.org/issue/U4-9490).
However considering that you need this now, an interim solution could be that you make sure your code is only run once when triggered by the .Saved / .Saving events.
One way to do this would be to check the last saved date (UpdateDate) in your code. If the content was saved within the last second of the current save operation, you know that this is a save event triggered by the save happening in SendToPublication action. Then you also know that the item has already been sent to publication and that this doesn't need to be done again - thereby preventing the endless loop from happening.

Coroutines, multiple requests in Lua

I've been poring over this subject for the past 12 hours, and I simply cannot seem to get anywhere. I do not even know if this is possible, but I'm hoping it is because it would go a long way to continuing my project.
What I am attempting to do is create coroutines so the particular program I use does not freeze up due to its inability to perform asynchronous http requests. I've figured out how to do that part, even though my understanding of coroutines is still in the "Huh? How does that work?" phase. My issue now is being able to respond to multiple requests with the correct information. For instance, the following should produce three separate responses:
foo(a)
foo(b)
foo(c)
where foo initiates a coroutine with the parameters inside. If all requested separately, then it returns the proper results. However, if requested as a block, it will only return foo(c)'s result. Now, I understand the reasoning behind this, but I cannot find a way to make it return all three results when requested as a block. To help understand this problem a bit, here's the actual code:
function background_weather()
local loc = url.escape(querystring)
weatherpage = http.request("http://api.wunderground.com/api/004678614f27ceae/conditions/q/" .. loc .. ".json")
wresults = json.decode(weatherpage)
--process some stuff here, mainly datamining
end
--send datamined information as a response
coroutine.yield()
end
And the creation of the coroutine:
function getweather ()
-- see if backgrounder running
if background_task == nil or
coroutine.status (background_task) == "dead" then
-- not running, create it
background_task = coroutine.create (background_weather)
-- make timer to keep it going
AddTimer ("tickler", 0, 0, 1, "",
timer_flag.Enabled + timer_flag.Replace,
"tickle_it")
end -- if
end -- function
The querystring variable is set with the initial request. I didn't include it here, but for the sake of testing, use 12345 as the querystring variable. The timer is something that the original author of the script initialized to check if the coroutine was still running or not, poking the background every second until done. To be honest, I'm not even sure if I've done this correctly, though it seems to run asynchronously in the program.
So, is it possible to receive multiple requests in one block and return multiple responses, correctly? Or is this far too much a task for Lua to handle?
Coroutines don't work like that. They are, in fact, blocking.
The problem coroutines resolve is "I want to have a function I can execute for a while, then go back to do other thing, and then come back and have the same state I had when I left it".
Notice that I didn't say "I want it to keep running while I do other things"; the flow of code "stops" on the coroutine, and only continues on it when you go back to it.
Using coroutines you can modify (and in some cases facilitate) how the code behaves, to make it more evident or legible. But it is still strictly single-threaded.
Remember that what Lua implements must be specified by C99. Since this standard doesn't come with a thread implementation, Lua is strictly single-threaded by default. If you want multi-threading, you need to hook it to an external lib. For example, luvit hooks Luajit with the libuv lib to achieve this.
A couple good references:
http://lua-users.org/wiki/CoroutinesTutorial
http://lua-users.org/wiki/ThreadsTutorial
http://lua-users.org/wiki/MultiTasking
http://kotisivu.dnainternet.net/askok/bin/lanes/comparison.html
Chapter 9.4 of Programming in Lua contains a fairly good example of how to deal with this exact problem, using coroutines and LuaSocket's socket.select() function to prevent busylooping.
Unfortunately I don't believe there's any way to use the socket.http functions with socket.select; the code in the PiL example is often all you'll need, but it doesn't handle some fairly common cases such as the requested URL sending a redirect.

How to stay RESTful with a complex API

My setup: Rails 2.3.10, Ruby 1.8.7
I need to implement an API that is essentially a GET but depending on a date, could involve DELETE and POST actions as well. Let me explain, for a particular day, the API needs to add 10 items to one table randomly selected from another table but this is only done once a day. If the items added are from the previous day, then the API needs to delete those items and randomly add 10 new ones. If multiple calls are made to the API in the same day, then it's just a GET after the initial creation. Hope this makes some sense.
How would I implement this as a RESTful API if at all possible.
How about?
GET /Items
If the next day has arrived, then generate 10 new items before returning them. If the next day has not arrived, then return the same 10 items you previously returned. There is no reason the server cannot update the items based on a GET. The client is not requesting an update so the request is still considered safe.
Not sure if I'm understanding you correctly, but just by looking at this, all I can think is the following: What a horrible thing, to perform an add which depending on what it's added, performs a delete. No disrespect, but seriously. Or maybe it is the way you are describing it.
Whatever the case, if you want to have a RESTful API, then you have to treat GET and PUT distinctively.
I don't think you have a clear use-case picture of how your API (or your system for that matter is to be done.) My suggestion would be to re-model this as follows:
Define a URI for your resource, say /random-items
a GET /random-items gets you between 0 and 10 items currently in the system.
a PUT/random-items with an empty body does the following:
delete any random items added on or before yesterday
add as many random items as necessary to complete 10
an invocation to DELETE /random-items) should return a 405 Method Not Allowed http error code.
an invocation to POST/random-items` should add no more than 10 items, deleting as needed.
/random-items/x is a valid URI so long as x is one of the items currently under /random-items.
A GET to it should return a representation for it or a 404 if it does not exist
A DELETE to it deletes it from under /random-items or 404 if it does not exist
A PUT to it should change its value if it makes sense (or return a 405)
A POST to it should return a 405 always
That should give you a skeleton sorta RESTful API.
However, if you insist, or need to overload GET so that it performs the additions and deletions behinds the scene, then you are making it non-RESTful.
That in itself is not a bad thing if you legitimately have a need for it (as no architectural paradigm is universally applicable.) But you need to understand what RESTful mean and when/why/how to break it.

How to get the Process Environment Block (PEB) from extern process?

I want to get the PEB from the "notepad.exe" process. Does someone know how to do it?
I tried the GetModuleHandle API, but it doesn't return a valid pointer (it return zero every time) because I have to be the caller process of that module.
For that reason, I want to know how to get it to work with EnumProcessModules or CreateToolhelp32Snapshot.
Matt Pietrek described how to do that in a 1994 Under the Hood column. It was about how to get the environment variables of another process, where the first step is to get a pointer to the PEB. To do that, he says, call NtQueryInformationProcess. The PROCESS_BASIC_INFORMATION structure it fills contains the base address of the PEB structure. (You'll need to use ReadProcessMemory to read it since the address will be in the context of the external process's address space, not yours.)
To call NtQueryInformationProcess, you'll need a handle to the process. If you started the process yourself (by calling CreateProcess), then you already have a handle. Otherwise, you'll need to find the process ID and then call OpenProcess. To get the process ID, search for the process you want with EnumProcesses or Process32First/Process32Next. (I prefer the latter because it provides more information with less work.)

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