I'm using the latest Google Chrome stable (19.0.1084.56 m) on Windows 7 and experimenting with Mutation observers for the first time. (The project is a user script for a third party website, the server of which I have no access to.)
So it happens that MutationRecord has a field oldValue:
record . oldValue
The return value depends on type. For "attributes", it is the value of the changed attribute before the change. For "characterData", it is the data of the changed node before the change. For "childList", it is null.
So I'm monitoring for changes to the characterData but when I get the MutationRecord the oldValue field is always null.
Should it be working, is there a possibility I've got something wrong, or is this feature just too bleeding edge to expect to work yet?
Is there somewhere I can find Google's documentation, bug report, feature request, etc that might declare whether this is implemented or when it might be?
Configure your observer with:
observer.observe(container, {
attributeOldValue : true
});
Full API documentation:
https://developer.mozilla.org/pt-BR/docs/Web/API/MutationObserver
Related
I am having troubles with the resetAuth() function. I implemented it roughly like this example, but I have no idea when it is being called. Adding a console output and observing the Stackdriver Log tells me that this function is never being called during what I would call a normal workflow.
The documentation is weirdly brief and is missing this part about why I need to implement it and when it is being called. Do I need to call resetAuth() manually on some point? Is there a button somewhere that calls this function?
I'm using the AuthType USER_PASS by the way and everything else seems to work just fine after some investigation and debugging.
I found this document called Community Connectors Developer Launch where, among other things, the following it listed (as of 2018-07-30):
What's next: Upcoming changes and improvements
Some of the features and improvements we'll be working on in the
coming months include:
Configuration and Authentication
Capability to execute the resetAuth function of community connectors from within Data Studio.
Does this mean that calling resetAuth() is currently not yet implemented?
resetAuth is called when the user revokes access to the connector via the https://datastudio.google.com/datasources/create endpoint.
There was a bug that caused this function to not be called for certain auth types, but it has been resolved.
A number of my tests use a DeleteCookies method which does this:
chromeDriver.Manage().Cookies.DeleteAllCookies();
This was great until today, when one of the tests made the app take exception:
The required anti-forgery cookie "__RequestVerificationToken" is not present.
So I decided to delete the specific cookie in question, rather than all of them:
chromeDriver.Manage().Cookies.DeleteCookieNamed("user%40user.com");
The specified cookie was not deleted.
To verify DeleteCookieNamed actually worked at all, I deleted two of the other cookies the app creates and it worked.
When a user logs in, the app sets the name of the cookie to their username (in this case, user#user.com) ...but presumably due to URL encoding, changes # to %40.
The cookies that did delete didn't contain %40.
If it was the case that you can't delete cookies where the name contains %40, then DeleteAllCookies wouldn't have worked. Therefore I suspect my targeted cookie has dependencies, similar to how foreign key constraints work in relational databases, such that I need to delete one or more other cookies in a specific order before I can delete the specified one.
A cursory glance at Google provides me with instructions on how to delete cookies in Chrome, rather than how Chrome deletes cookies. Joy. I've run out of time today, please do you have any insights?
The way I got round this issue when I had it was to create the cookie through selenium, and then I was able to delete it. I did find it easier though not to use the # in the cookie names. Hope that helps.
This seems an appropriate work-around for my particular situation - run the CanLogIn test last, using a Playlist:
https://stackoverflow.com/a/29039261/1875540
Use Chrome DevTools:
https://chromedevtools.github.io/devtools-protocol/tot/Network/#method-deleteCookies
The code will be like this:
ChromeDriver driver;
var parameters = new Dictionary<string, object>
{
["name"] = "user%40user.com";
};
driver.ExecuteChromeCommand("Network.deleteCookies", parameters);
You can do this by Selenium DevTools as well. But since they have some problems with integrations, and you may need to upgrade the library after every google update, using the above code can be more efficient and easier.
I am currently reading Async Javascript by Trevor Burnham. This has been a great book so far.
He talks about this snippet and console.log being 'async' in the Safari and Chrome console. Unfortunately I can't replicate this. Here is the code:
var obj = {};
console.log(obj);
obj.foo = 'bar';
// my outcome: Object{}; 'bar';
// The book outcome: {foo:bar};
If this was async, I would anticipate the outcome to be the books outcome. console.log() is put in the event queue until all code is executed, then it is ran and it would have the bar property.
It appears though it is running synchronously.
Am I running this code wrong? Is console.log actually async?
console.log is not standardized, so the behavior is rather undefined, and can be changed easily from release to release of the developer tools. Your book is likely to be outdated, as might my answer soon.
To our code, it does not make any difference whether console.log is async or not, it does not provide any kind of callback or so; and the values you pass are always referenced and computed at the time you call the function.
We don't really know what happens then (OK, we could, since Firebug, Chrome Devtools and Opera Dragonfly are all open source). The console will need to store the logged values somewhere, and it will display them on the screen. The rendering will happen asynchronously for sure (being throttled to rate-limit updates), as will future interactions with the logged objects in the console (like expanding object properties).
So the console might either clone (serialize) the mutable objects that you did log, or it will store references to them. The first one doesn't work well with deep/large objects. Also, at least the initial rendering in the console will probably show the "current" state of the object, i.e. the one when it got logged - in your example you see Object {}.
However, when you expand the object to inspect its properties further, it is likely that the console will have only stored a reference to your object and its properties, and displaying them now will then show their current (already mutated) state. If you click on the +, you should be able to see the bar property in your example.
Here's a screenshot that was posted in the bug report to explain their "fix":
So, some values might be referenced long after they have been logged, and the evaluation of these is rather lazy ("when needed"). The most famous example of this discrepancy is handled in the question Is Chrome's JavaScript console lazy about evaluating arrays?
A workaround is to make sure to log serialized snapshots of your objects always, e.g. by doing console.log(JSON.stringify(obj)). This will work for non-circular and rather small objects only, though. See also How can I change the default behavior of console.log in Safari?.
The better solution is to use breakpoints for debugging, where the execution completely stops and you can inspect the current values at each point. Use logging only with serialisable and immutable data.
This isn't really an answer to the question, but it might be handy to someone who stumbled on this post, and it was too long to put in a comment:
window.console.logSync = (...args) => {
try {
args = args.map((arg) => JSON.parse(JSON.stringify(arg)));
console.log(...args);
} catch (error) {
console.log('Error trying to console.logSync()', ...args);
}
};
This creates a pseudo-synchronous version of console.log, but with the same caveats as mentioned in the accepted answer.
Since it seems like, at the moment, most browsers' console.log's are asynchronous in some manner, you may want to use a function like this in certain scenarios.
When using console.log:
a = {}; a.a=1;console.log(a);a.b=function(){};
// without b
a = {}; a.a=1;a.a1=1;a.a2=1;a.a3=1;a.a4=1;a.a5=1;a.a6=1;a.a7=1;a.a8=1;console.log(a);a.b=function(){};
// with b, maybe
a = {}; a.a=function(){};console.log(a);a.b=function(){};
// with b
in the first situation the object is simple enough, so console can 'stringify' it then present to you; but in the other situations, a is too 'complicated' to 'stringify' so console will show you the in memory object instead, and yes, when you look at it b has already be attached to a.
I need trigger able to detect that polled Zabbix agent items does not returns data.
For zabbix trapper items this functionality is covered by nodata() function (Heartbeat lost detection in Zabbix documentation) but I need similar functionality supported for Zabbix agent items.
For example, a have defined Zabbix agent UserParameter:
UserParameter=custom.mssqlping,/usr/local/scripts/mssqlping.sh.
The script mssqlping.sh returns 0/1. I need to cover situation when mssqlping.sh script is broken and returns empy string, which is not stored in zabbix because it is not number.
How to detect that periodically polled item data are no longer coming?
It is not that it's not stored that creates the problem but the fact that it is not being considered as a valid item anymore so you can't trigger anything out of it. There is a plenty of related bug reports related to it. AFAIk your options:
Adjust the script to return a numeric value in case of errors
Use 2.2's "internal events" to detect the "becomes unsupported" event
Make and external script that will query the database directly and will notify you on its own or triggering a condition through zabbix's trappers
Or the option here is to trigger based on nodata()
from: https://www.zabbix.com/forum/zabbix-help/41652-zabbix-trigger-timeout?p=245422#post245422
{myserver:example.iregexp("/string/",1m)}=1 AND {myserver:example.nodata(1m)}=0
some more reading: https://zabbix.org/wiki/Trigger_examples
Background:
Developing a trading system which subscribe to many events which are sent by API of Interactive Brokers. One interesting event is about my trading account value which fluctuates during trading hour so I would prefer to see the information with accountvalueupdate event immediately. I develop this one based on ActiveX api and c# in Visual Studio 2010.
the presentation I wanna check this information is to use a gauge developed by(http://www.devexpress.com/Products/NET/Controls/WinForms/Gauges/). This gauge looks fancy but the principle should be similar to the normal gauge we use in Visual Studio. It seems like I could only update the value of the gauge by databinding since I tried to assign updated account value to this.myGauge.value and failed.
I build up MySql connection between MySql and VS2010. I create only one table in MySQL which is called account. For the sake of simplicity, i only have two column(accountID and accountValue) and one row|(which means when event comes with new accountValue, I just overwrite the value of accountValue last session then the number of row is always one. really simple idea.....).In that Gauge proporties I found databinng option and I setted up by using advanced option to navigate throw available table and bind it to the only useful column accountValue.
Issue:
I set up the default value of the accountValue as 500 as default for test. I build my software. The gauge shows 500 correctly.
Of course, my real account value is not 500, so Now I click one button to connect to API and start listening the event. After few seconds, event arrives since I opened on Console for managing the mysql table and use select * from account to continuously watch the update. I noticed the value of accountValue column(TABLE WORKS RIGHT AND WE ONLY HAVE ONE ROW, OEVERWRITTING MODE) becomes the right one, for example, 35000.
HOWEVER, THE GAUGE DOES NOT CHANGE AT ALL...!! Now If i closed my software and build again, the gauge shows the right value 35000. Now I shut down the api and no coming event and only use commandline of mysql to change the value of accountValue again to 500. NO UPDATING in gauge as well.
It looks like the gauge only read the value of table during the build session or when it starts and never listen to the update of binding databases.
By the way, I tried to set up the biding data mode to either "onValidation" or "onPropertieschanged" but it does not solve although the "onPropertieschanged" looks the right one....
I tried to assign updated account value to this.myGauge.value...
Unfortunately, the information you provided doesn't allow to clearly diagnose this problem. There is no the Value property neither in WinForms GaugeControl nor in CircularGauge (as soon as in Linear/Digital/StateIndicator gauge), but only in ASPxGaugeControl (ASPxGaugeControl.Value). So, please provide a full sample code that doesnot work on your side.
All these properties can be changed manually in code or data-bound to data sources using the standard .NET data-binding mechanism:
The ArcScaleComponent.DataBindings property allows you to data-bind
to the current value of a circular gauge's scale (ArcScale.Value).
The LinearScaleComponent.DataBindings property allows you to
data-bind to the current value of a linear gauge's scale
(LinearScale.Value).
The DigitalGauge.DataBindings property allows you to data-bind to the
text displayed by a digital gauge.
The StateIndicatorComponent.DataBindings property allows you to
data-bind to a state of a state indicator gauge.
Please, review the following articles for more details: Data Binding.
The databinding feature is demonstrated in the Gauge's Main Demo project (the DataBinding module):
this.arcScaleComponent2.DataBindings.Add(
new System.Windows.Forms.Binding("Value", this.productsBindingSource,
"UnitsOnOrder", true, System.Windows.Forms.DataSourceUpdateMode.Never));
P.S. Please use the DevExpress Support Center to ask a questions or report issues, because there is no guarantee of DX involvement when you use the communities, newsgroups or other communication channels.