I'm reviewing my method for retrieving appsettings values from my config files. Before I would store the value in a static variable in a global ConfigurationManager class to avoid multiple unnecessary disk reads to the web.config file. It appears that was unnecessary as the WebConfigurationManager class already does this. Is this indeed the case? If I issue the following command 10 times in a row, how many times would it actually access the web.config file?
myConfigValue = WebConfigurationManager.AppSettings["MyConfigValue"];
It would only go to disk one time, and even then it probably already did it at the first request for any page in the app.
It will have to do a lookup on your "MyConfigValue" string each time, so there might be some room for improvement if you can put this somewhere that you only need to do that part once.
Either way, it's a micro-optimization.
none. the web.config file is read once, on application start...
http://www.google.com/search?hl=en&q=web.config+changes+require+iis+restart&btnG=Google+Search&aq=f&oq=&aqi=
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I've written a language server extension for VS code. In order to improve start-up time, I'd like to cache some global state. I'm struggling to find a safe, user transparent, location.
The cache is shared between all workspaces
It consists of 200-300MB of serialized data
It should persist between updates of the extension
The extension is cross-platform
I've discovered the following four options, but none of them seem appropriate:
ExtensionContext.extensionPath: This is almost perfect. Obvious to the user, safe sandboxed space. However, it's wiped on extension update.
ExtensionContext.storagePath: This is not global, and hard for the user to clear, so would very quickly end up using GBs of storage space.
ExtensionContext.globalState: Placing 300MB of binary data into a JSON dictionary store seems bad.
%UserData%/linux/OSX equivalents: Adding and deleting files in uncontrolled general userspace is a risk I'd rather avoid.
Where's the appropriate place to store this data?
The January 2019 release of VS Code added ExtensionContext.globalStoragePath, which is a global version of storagePath
An absolute file path in which the extension can store global state. The directory might not exist on disk and creation is up to the extension. However, the parent directory is guaranteed to be existent.
https://code.visualstudio.com/updates/v1_31#_global-storage-path
You might want to consider creating a file path defined in the User Settings; I think this solution covers all of your requirements.
You can set a default value in the package.json and it's transparent to the user - they can change it if they want to.
More info here: https://code.visualstudio.com/api/references/contribution-points#contributes.configuration
I'm programming my fist SwiftApp got stuck setting up Core data. Since I'm integrating it into existing code I can't have Xcode set it up on Prohect init anymore. Furthermore I als want to understand what the lines of code actually do. Since all Core libraries are secret I am stuck with Apple's Docs which are not very clear on the matter.
Pfew... with that out of the way here is the question; What is the significance of the name passed to...
let container = NSPersistentContainer(name: "Core_Data")
...in the App Delegate file. I had set it up before but during compilation Xcode complained that it could not find the specified Name's module. Changing it to my project's name, the core data file I had created or the name of the Database passed to the menu when adding a Core Data file did not seem to help at all. Searching the web and a few tutorials people just fly over it and it is still very much unclear to me.
Any help would be much appreciated!
The string passed there is used for two things. If you were to pass the string Foo, Core Data would attempt:
To find the data model by looking for Foo.xcdatamodel or Foo.xcdatamodeld.
To find (or create) the persistent store, using the name Foo.sqlite.
Even an incorrect string value (i.e. one that doesn't match the name of your data model) should not cause a compilation error. It might cause an error at run time if iOS can't find the named data model.
I'm trying to build a system that can purge and regenerate URLs as required for a particular system. I previously was having issues with purging when the system located the object by hash but missed the variant as I didn't have a "purge;" in my vcl_miss (only in my vcl_hit, some guides/example vcl files do not mention this need but the main documentation does here).
What I'm trying to figure-out is if I need to do something similar for a REGEN call. From my understanding, "set req.hash_always_miss = true;" will mean that the old hash is missed and a new hash object is generated. Subsequent calls will find the new hash, but may still miss that object if there is not an appropriate variant in the cache.
Could someone confirm for me whether a subsequent request missing the variant in the new object will lead directly to a cache miss and fetch, rather than finding any of the variants from the previous object?
hash_always_miss will only influence the current/ongoing request and the cache contents that it replaces. A fetch will always happen, and the object will be put into the cache using the same rules as any other miss/fetch sequence.
The "old" other variants of the same hash are still valid objects and will be served to a client indicating request headers matching the varied headers.
hash_always_miss will replace the current variant, and nothing else.
To answer your question, the second part of your sentence is most correct.
I'm trying to come up with a way to make it easy to switch out our "mock" data services and our live ones. Basically, we'll have live servers with real web services, but for whatever reason, a developer may want to load data from static files (file urls).
I figured I would solve this problem by creating categories that override the methods that fetch the data, thus leaving original code untouched (it has no concept of the "mock" data). I don't want to litter my code with #ifdef.
I can put an #ifdef at the very beginning of each file that has categories in it, and I can set a custom flag in the configuration settings, but I'd rather just have a way to include or exclude the files depending on the configuration. Is that possible? How do you solve this problem?
See http://lists.apple.com/archives/xcode-users/2009/Jun/msg00153.html
The trick is to define EXCLUDED_SOURCE_FILE_NAMES in the configuration you want to exclude the files from, and set the value of that custom build setting to a list of the file names (or a pattern that matches those, and only those, file names).
I would recommend creating two targets one of which has the mock categories included and another one which does not.
When you want to test, just build the target containing the mock categories. Everything else can remain identical.
If you would like to add a file but do not wont to compile it. Go to (for all your targets) project>build phases>compile source and take out the file that you do not want to compile.
I have two projects:
ASP.Net 3.5 website (frontend, UI)
VB Class Library (dataaccess logic)
Where should I save my connectionString, so that I can use if from the class library? And how does this affect where it is placed when I deploy/publish?
Note:
I don't want to pass it to every function in my VB Class
Depending on how you constructed your DAL -- LINQ, TableAdapters, etc. -- it may automatically look for it in the web.config file. If you created the DAL via a designer, likely it stores the default connection string in the app.config file for you class library. I copy the connection strings section from the app.config file to my web.config and change the connection string to the correct database (I have separate web.config's for DEV/QA/PROD). This makes it trivial since the designer generated code already has the code implemented to retrieve it from the configuration file.
If you are hand-coding your DAL and need to pass in the connection string, I suggest setting up a strongly-typed configuration class that interfaces to the web.config and does lazy loading of your configuration values. Use a factory to create your DAL and inject the configuration class into your factory via constructor so that it knows how to create your DAL with the connectionsString retrieved from the configuration file.
My question came from having spent half a day of trying to make this work, but I kept getting the wrong connection when deploying (where I use another database).
My problem was, that I was using
My.Settings.DefaultConnectionString
...To retrieve the connectionString in my VB Class Library.
After following tvanfossons anwer, I dug around some more and found out, that I can simply use (after referencing system.configuration) :
System.Configuration.ConfigurationManager.ConnectionStrings.Item("DefaultConnectionString").ConnectionString
It looks in the web-config for webapplications and app.config for windows/class library apps.
I am glad it now works, but even more glad I know why. ;)
I had the same issue you were having and I ended up using the System.Configuration.ConfigurationManager class to obtain the connection string stored in my web.config file from my class library like Kjensen's answer suggested. This worked wonders, if I had more experience I would vote that answer up.
I needed the connection string to build my Linq2Sql data context, which this method provided me with.
I now build my data context like below (remembering to add a reference to System.Configuration) -
public MyDataContext() : base(System.Configuration.ConfigurationManager.ConnectionStrings["MyConnectionString"]
.ConnectionString, mappingSource)
And as long as the web.config file contains "MyConnectionString" the configuration manager takes care of the rest.
We keep ours in the machine.config of each server and have a custom DAL to handle all DB interaction for our web apps.
Put it in the web.config in the connection strings section.
In the VB project use HttpContext.Current.GetSection to retrieve the section.
A fellow developers idea once was that we should store all the connection strings in a database table.
Don't try doing that. You won't get very far. :)