I've been having problems with conflicting updates in Marklogic. I'm aware of the cause, but I don't know how to fix it.
I have 1 main (.sjs) file which calls two different (.sjs) files which both update a set of documents. In the main file I use: declareUpdate({explicitCommit: true}); and then in the separate files I use the command xdmp.commit(); after updating the documents. However, I'm still getting: XDMP-CONFLICTINGUPDATES.
Part of the code: Main.sjs:
function main(){
declareUpdate({explicitCommit: true});
function.to.file.1();
function.to.file.2();
}
file1.sjs:
//make some docs and insert them into ML
function file1Function(){
for (let d of someCollectionOfData) {
xdmp.documentInsert('/a/uri/filexx.json', d, {collections: aCollectionName1});
};
xdmp.commit();
}
file2.sjs:
//adjust docs made in file1 and put them back into ML
funtion file2Function(){
for (let d of xdmp.directory('/location/of/aCollectionName1/','infinity')) {
let dObj = d.toObject();
dObj.addSomething = 'something';
xdmp.documentInsert(fn.documentUri(d), dObj, {collections: aCollectionName1});
}
xdmp.commit();
}
It must mean your file1 is located inside '/location/of/aCollectionName1/'. Keep in mind that MarkLogic doesn't commit immediately when you invoke xdmp.commit(). Actual persisting is always postponed until after all code has executed. It therefor doesn't make much sense to invoke xdmp.commit() more than once in one request. You won't be able to read your updates after xdmp.commit().
HTH!
Related
Node noobie here. After doing a lot of searching and reading a lot of articles, posts, and Stackoverflow discussions, I remain stuck when implementing nested async calls in node.js. Here is the scenario I'm trying to implement:
My code receives an event to open the third party CSV file. Once the file is opened, the content must be validated. If the data is valid, it gets persisted to the backend data store. Any exception to the validation rules must be stored in a separate error log on the back end.
I've modularized the solution into separate functions: one function to open the file, the next function to validate the contents of the file, the next function to persist the content, and finally last function to persist eventual errors generated by the validation function.
Each of these functions incurs certain latency, which necessitates using callbacks. But because the nesting of the callbacks can go a few levels deep, I've tried to keep my code shallow and to separate concerns and compartmentalize the logic in separate modules/functions. Now when I'm trying to string them together, I am failing at implementing correct callback logic.
For example, my top level module looks something like this:
module.exports = {
openFile: (filePath) => {
// code to open file and load the content
readAndParseFile(fileContent, validateAndReturnStatus);
}
}
function readAndParseFile(fileContent, next) {
// code to parse file content into rows of data
next(rows, persistValues);
}
function validateAndReturnStatus(rows, next) {
// code to validate
if(valid) {
persistValues(row, sendResponse);
}
}
function persistValues(row, next) {
//code to persist validated data
next('success');
}
function sendResponse(status) {
console.log(status);
}
Above is a very simplified pseudo-code, but I hope it illustrates my intention. My question is: what is the most reliable, correct way to nest functions that are unavoidably latent and make sure that the batch process is waiting on the correct status at the end of the processing?
Thanks.
I've got a question regarding loading external files in node.
Basically I'm loading an external JSON file that contains some configuration, and this file is modified by an external process every 10 minutes. How can i reload this file every 10 minutes, without restarting node?
I've tried this solution:
delete require.cache['/home/conf/myfile.json']
but some people have advised against it. Can anybody help me?
At the end I changed my code and I now use fs.readFile to load my json file, instead of using a require.
I then used node-watch to check for changes in file and reload it.
Couple options. You could just use setInterval for 10 minutes and read the file in the callback. Otherwise you could use fs.watch and trigger the reload when the file actually changes.
update based on comment
If you're using require, it will only load the file once, regardless of how many times you're requiring it and there isn't really a mechanism to invalidate a required file. You could create a wrapper around the functionality and require that instead. Your wrapper is the file you require, and it exposes a function which returns your current config. Inside that module you could create the setTimeout refresh mentioned above.
You can have a look at my module-invalidate module that allows you to invalidate a required module. The module will then be automatically reloaded on further access.
Example:
module ./myModule.js
module.invalidable = true;
var count = 0;
exports.count = function() {
return count++;
}
main module ./index.js
require('module-invalidate');
var myModule = require('./myModule.js');
console.log( myModule.count() ); // 0
console.log( myModule.count() ); // 1
setInterval(function() {
module.constructor.invalidateByExports(myModule);
console.log( myModule.count() ); // 0
console.log( myModule.count() ); // 1
}, 10*60*1000);
I'm working on a project (creating a browser based check list). One of my goals has been to write every piece by hand without a library like jquery or a mysql database.
Currently I'm trying to create on object for managing tasks. I'm not finished the primary function, but everything is closed, and I don't detect any errors. Furthermore, I'm haven't iterated it or called it's functions yet, so there's nothing to reference it yet. When I comment it out, the script runs normally.
I've included the xml request links up above and tested them successfully in a separate portion of the script.
I'm testing in firefox.
I'm writing this in SciTE
Here's the code:
function Task(name,node,childNode,divClass,content,onclick)
{
function retrieveTask(node,childNode)
{
var taskArray = [];
taskArray.push(xmlDoc.getElementsByTagName(name)[node].childNodes[childNode].nodeValue;)
taskArray.push(xmlDoc.getElementsByTagName(description)[node].childNodes[childNode].nodeValue;)
taskArray.push(xmlDoc.getElementsByTagName(complete)[node].childNodes[childNode].nodeValue;)
return taskArray;
}
function displayTask(name,content)
{
var task = retrieveTask(node,childNode);
var clickDiv = "";
formatDiv(name,"task",task[1],clickDiv);
task[2] === true ? formatDiv(name+1,"incompleteBox"," ",clickDiv) : formatDiv(name+1,"completeBox","O",clickDiv);
}
}
If anyone could give me some insight or tips that would be awesome. This isn't homework, it's a hobby, so it's a self teaching process.
...childNodes[childNode].nodeValue;)
should be );
I have file called common.js and it's included in each page of my site using <script />.
It will grow fast as my sites functionality will grow (I hope; I imagine). :)
Lets example I have a jQuery event:
$('#that').click(function() {
one_of_many_functions($(this));
}
For the moment, I have that one_of_many_functions() in common.js.
Is it somehow possible that JavaScript automatically loads file one_of_many_functions.js when such function is called, but it doesn't exist? Like auto-loader. :)
The second option I see is to do something like:
$('#that').click(function() {
include('one_of_many_functions');
one_of_many_functions($(this));
}
That not so automatically, but still - includes wanted file.
Is any of this possible? Thanks in an advice! :)
It is not possible to directly auto-load external javascripts on demand. It is, however, possible to implement a dynamic inclusion mechanism similar to the second route you mentioned.
There are some challenges though. When you "include" a new external script, you aren't going to be able to immediately use the included functionality, you'll have to wait until the script loads. This means that you'll have to fragment your code somewhat, which means that you'll have to make some decisions about what should just be included in the core vs. what can be included on demand.
You'll need to set up a central object that keeps track of which assets are already loaded. Here's a quick mockup of that:
var assets = {
assets: {},
include: function (asset_name, callback) {
if (typeof callback != 'function')
callback = function () { return false; };
if (typeof this.assets[asset_name] != 'undefined' )
return callback();
var html_doc = document.getElementsByTagName('head')[0];
var st = document.createElement('script');
st.setAttribute('language', 'javascript');
st.setAttribute('type', 'text/javascript');
st.setAttribute('src', asset_name);
st.onload = function () { assets._script_loaded(asset_name, callback); };
html_doc.appendChild(st);
},
_script_loaded: function (asset_name, callback) {
this.assets[asset_name] = true;
callback();
}
};
assets.inlude('myfile.js', function () {
/* do stuff that depends on myfile.js */
});
Sure it's possible -- but this can become painful to manage. In order to implement something like this, you're going to have to maintain an index of functions and their corresponding source file. As your project grows, this can be troublesome for a few reasons -- the 2 that stick out in my mind are:
A) You have the added responsibility of maintaining your index object/lookup mechanism so that your scripts know where to look when the function you're calling cannot be found.
B) This is one more thing that can go wrong when debugging your growing project.
I'm sure that someone else will mention this by the time I'm finished writing this, but your time would probably be better spent figuring out how to combine all of your code into a single .js file. The benefits to doing so are well-documented.
I have created something close to that a year ago. In fact, I have found this thread by search if that is something new on the field. You can see what I have created here: https://github.com/thiagomata/CanvasBox/blob/master/src/main/New.js
My project are, almost 100% OOP. So, I used this fact to focus my solution. I create this "Class" with the name "New" what is used to, first load and after instance the objects.
Here a example of someone using it:
var objSquare = New.Square(); // Square is loaded and after that instance is created
objSquare.x = objBox.width / 2;
objSquare.y = objBox.height / 2;
var objSomeExample = New.Stuff("some parameters can be sent too");
In this version I am not using some json with all js file position. The mapping is hardcore as you can see here:
New.prototype.arrMap = {
CanvasBox: "" + window.MAIN_PATH + "CanvasBox",
CanvasBoxBehavior: "" + window.MAIN_PATH + "CanvasBoxBehavior",
CanvasBoxButton: "" + window.MAIN_PATH + "CanvasBoxButton",
// (...)
};
But make this more automatic, using gulp or grunt is something what I am thinking to do, and it is not that hard.
This solution was created to be used into the project. So, the code may need some changes to be able to be used into any project. But may be a start.
Hope this helps.
As I said before, this still is a working progress. But I have created a more independent module what use gulp to keep it updated.
All the magic que be found in this links:
https://github.com/thiagomata/CanvasBox/blob/master/src/coffee/main/Instance.coffee
https://github.com/thiagomata/CanvasBox/blob/master/src/node/scripts.js
https://github.com/thiagomata/CanvasBox/blob/master/gulpfile.js
A special look should be in this lines of the Instance.coffee
###
# Create an instance of the object passing the argument
###
instaceObject = (->
ClassElement = (args) ->
window[args["0"]].apply this, args["1"]
->
ClassElement:: = (window[arguments["0"]])::
objElement = new ClassElement(arguments)
return objElement
)()
This lines allows me to initialize a instance of some object after load its file. As is used in the create method:
create:()->
#load()
return instaceObject(#packageName, arguments)
I spent the better part of last month beating my head against the wall before I came up with an easy way to dynamically load, and chain together HTML canvas classes which are stored on the server, but, obviously, initialized on the client (harder than it sounds when the ordering is important in an asynchronous environment).
I was wondering if someone could help me find a way to load simple javascript scripts. Lets define a load('foo.js') function which instructs the client to load script foo.js from the server and execute it as javascript code.
Given the three files, stored on the server:
A.js
a = 10;
B.js
load('A.js');
b = a + 10;
C.js
load('B.js');
c = b + 10;
If the client issues the command load('C.js'); what's the easiest/most reliable way to implement this. One idea I had was to scan the code serverside and return all the scripts at once. This requires the minimal amount of php requests. However, if the client has already requested C.js before, the script should exist client side, and this would be inneficient, especially if C.js and all its dependent files are large. Another option I considered was to wrap all of these serverside scripts in an object like so, for C.js above:
{
depenencies: ['B.js'] ,
code : 'c.age = b.age + 10;'
}
I just don't know how to 'pause' execution of script C.js after the load('B.js') statement, and then resuming it after B.js has been loaded.
EDIT Thanks to redsqaure for suggesting yepnope and requirejs. Unfortunately, I do not like them for several reasons. For one, requirejs is difficult (I am sure I will come under criticism for this one). My main gripe with this is that, if it is so difficult to learn, I might as well recreate it myself, learning it in the process, AND having greater control over it. Second, it requires you to change your style of writing. Switching to Dojo and having to use dojo.declare("ClassName", [ParentA,ParentB], {...}); to declare classes is one thing, but wrapping every snippet of code in require(['A','B',...], function(){}); is another. Finally, I don't know how simple it will be to instruct where to look for files. I want the user to be able to define a 'PATH' variable server side, and have the search occur in each of the folders/subfolders of the 'PATH'
Depends on how optimized you want it to be. Either you can go the route of synchronous XHR or use a callback (async and recommended). If you were to go the second route your code would look something like:
// Say C.js is dependent on A.js and B.js..
load(["A.js","B.js"], function() {
// code goes here
});
EDIT
Taking a second look after you feedback what you want is somewhat possible, but would be brittle and hard to write in javascript. Below i have a sample/untested implementation of a dependency loader where a file can only have one call to load("file.js") possible. This would be more complex for multiple possible dependencies. Also I'm assuming these files are coming from the same domain.
// Usage: load("A.js")
// A.js -> B.js -> C.js
window.load = (function() {
var loaded = {};
return function(str, /* internally used */ callback) {
if(!loaded[str]) {
loaded[str] = true;
$.get(str, function(data) {
var matches = data.match(/load\(['|"](.*)["|']\)/);
if(matches.length > 1) { // has deps
window.load(matches[1], function() {
window.eval(data);
if(!!callback) callback();
});
} else { // no deps
window.eval(data);
}
});
}
}
})();
Why not look into a script loader like yepnope.js or require.js