I have created sample function here in c# which set the location value based on the parameter. I want to write below expression by using arm template style format.
public static Main(string name)
{
string location = string.Empty;
if(name == "uksouth")
{
location = "UKS";
}else if(name == "ukwest")
{
location = "UKE";
}else if(name == "IndiaWest")
{
location = "INDW";
}
else {
location = "INDS";
}
}
I have written this for one match condition, but i want to return value based on the user resource group.
"value": "[if(equals(resourceGroup().location,'uksouth'), 'UKS', 'EUS')]"
Unfortunately, ARM templates don't provide the equivalent of a "switch" mechanism, which is what might make this easier. However, you can nest multiple if statements. The syntax is a bit clunky, but this should be the equivalent of the code you've written:
"value": "[if(equals(resourceGroup().location,'uksouth'), 'UKS', [if(equals(resourceGroup().location,'ukwest'), 'UKE', [if(equals(resourceGroup().location,'IndiaWest'), 'INDW', 'INDS')])])]"
Here's the same code with a little formatting applied to make it more obvious what's happening here:
"value": "
[if(equals(resourceGroup().location,'uksouth'),
'UKS',
[if(equals(resourceGroup().location,'ukwest'),
'UKE',
[if(equals(resourceGroup().location,'IndiaWest'),
'INDW',
'INDS')])])]
"
You might also consider the approach described in this answer for a bit of a cleaner solution.
Try defining a variable that is an object used like a hashtable. Retrieve different properties from the object by key-name, accessing the properties as key-value pairs. I use something very similar to lookup values inside my ARM templates.
"variables" {
"locationShorten": {
"uksouth": "UKS",
"ukwest": "UKE",
"IndiaWest": "INDW",
"IndiaSouth": "INDS"
},
"locationShort": "[variables('locationShorten')[resourceGroup().location]]"}
Microsoft defines an object's properties as key-value pairs. "Each property in an object consists of key and value. The key and value are enclosed in double quotes and separated by a colon (:)."
Source: https://learn.microsoft.com/en-us/azure/azure-resource-manager/templates/data-types#objects
As for the documentation on using [] to access object properties, I can no longer find it for JSON but it is there for BICEP. "You can also use the [] syntax to access a property."
Source: https://learn.microsoft.com/en-us/azure/azure-resource-manager/bicep/data-types#objects
Related
I'm trying to use Pkcs11Interop to sign a message using the private key from a smart card certificate in a C# application. The smart card we are using contain multiple certificates - usually one is for signing, and one is for authentication. If I were using X509Certificate2, I'd filter certificates based on the X509KeyUsageFlags I'm looking for. I'm struggling to figure out how to approach this using PKCS11.
The code I'm starting with is below. When I call session.FindAllObjects, I'm getting 2 certificates in the result (which is expected, since that is how many certificates are on the smart card.)
I've tried using GetAttributeValue to read various attributes and see if I can use those to identify the correct certificate - strangely, they all return null/0 values. Querying the CKA_SENSITIVE attribute returns True (which is, again, expected), but apparently I cannot read other attributes from the objects.
Am I doing something incorrect in my usage of GetAttributeValue? Or is there some other way I should be approaching this problem?
public byte[] SignMessage(byte[] message, string pin)
{
var factories = new Pkcs11InteropFactories();
using (IPkcs11Library pkcs11Library = factories.Pkcs11LibraryFactory.LoadPkcs11Library(factories, DriverPath, AppType.SingleThreaded))
{
ISlot slot = GetSlot(pkcs11Library);
if (slot == null)
{
return null;
}
using (ISession session = slot.OpenSession(SessionType.ReadWrite))
{
session.Login(CKU.CKU_USER, pin);
var searchTemplate = new List<IObjectAttribute> {
factories.ObjectAttributeFactory.Create(CKA.CKA_CLASS, CKO.CKO_PRIVATE_KEY),
factories.ObjectAttributeFactory.Create(CKA.CKA_KEY_TYPE, CKK.CKK_RSA),
factories.ObjectAttributeFactory.Create(CKA.CKA_SIGN, true),
};
List<IObjectHandle> foundObjects = session.FindAllObjects(searchTemplate); // foundObjects.Count = 2!
IObjectHandle privateKey = foundObjects.FirstOrDefault();
var readResult = session.GetAttributeValue(privateKey, new List<CKA>() { CKA.CKA_LABEL });
var label = readResult[0].GetValueAsString(); // label ends up being null!
byte[] result = null;
using (IMechanism signingMechanism = session.Factories.MechanismFactory.Create(CKM.CKM_SHA256_RSA_PKCS))
{
result = session.Sign(signingMechanism, privateKey, message);
}
session.DestroyObject(privateKey);
session.Logout();
return result;
}
}
}
I came up with a solution through trial-and-error that seems to function correctly. I'm not sure if this is the correct approach, since it seems quite convoluted, so any feedback would be appreciated. I discovered that the contents of the card include a variety of objects, and a single key pair consists of three objects: a CKO_CERTIFICATE object (which seems to contain the brunt of the metadata about the certificate/keypair), a CKO_PRIVATE_KEY object and a CKO_PUBLIC_KEY object. Each of these has the CKA_ID property populated, and the objects that are part of the same key pair should have the same CKA_ID.
So I built a CertificateWrapper wrapper class to hold references to each of the three objects. I then looped over all objects on the smart card, and built CertificateWrapper objects for each unique key pair.
Then, I was able to construct an X509Certificate2 object using the CKA_VALUE attribute on the CKO_CERTIFICATE object. From there, I was able to build a X509Certificate2Collection object using an array of all of the X509Certificate2 objects I made. I could then use the .Find method (or any other method I wanted) on X509Certificate2Collection to filter down to the particular certificate I was looking for.
Once I had the X509Certificate2 object I was looking for, I was able to map it back to the CertificateWrapper object by matching the serial number from the X509Certificate2 against the CKA_SERIAL_NUMBER attribute from the CKO_CERTIFICATE object. Finally, I was able to use the CKO_PRIVATE_KEY object associated with that CKO_CERTIFICATE to do the signing operation.
Like I said, this seems very round-about, but seemed to allow me to find the correct certificate/key pair I needed for my specific workflow. Hope this explanation might be useful to someone, and I also welcome any feedback on problems with this approach and/or better ways to handle this.
Need some understanding regarding performance when using a single if vs ternary operator.
I create a wrapper instance wherein I initialize its variables. Eg below :
public class MyWrapperClass{
public string sUserName;
public MyWrapperClass(){
this.sUserName = '';
}
}
Now, while I assign the values returned from back-end to the wrapper variables, I use a single if to check if the value returned from the back-end is not blank.
Below is what I do:
if(String.isNotBlank(myObj.myField__c)){
myWrapperInstance.sUserName = myObj.myField__c;
}
I don't have an else condition here because I've already initialized the the variable as an empty string and hence if no value exists for the field, then my variable would hold an empty string.
However, I need to understand if it makes sense to use below:
myWrapperInstance.sUserName = String.isNotBlank(myObj.myField__c) ? myObj.myField__c : myObj.myField__c;
OR
myWrapperInstance.sUserName = myObj.myField__c != null ? myObj.myField__c : myObj.myField__c;
I need help understanding what is the better of the two from performance standponint?
With arrays you can use a subscript to access Array Elements directly. You can read or write to them. With Sets I am not sure of a way to write its Elements.
For example, if I access a set element matching a condition I'm only able to read the element. It is passed by copy and I can't therefore write to the original.
For example:
columns.first(
where: {
$0.header.last == Character(String(i))
}
)?.cells.append(value: addValue)
// ERROR: Cannot use mutating member on immutable value: function call returns immutable value
You can't just change things inside a set, because of how a (hash) set works. Changing them would possibly change their hash value, making the set into an invalid state.
Therefore, you would have to take the thing you want to change out of the set, change it, then put it back.
if var thing = columns.first(
where: {
$0.header.last == Character(String(i))
}) {
columns.remove(thing)
thing.cells.append(value: addValue)
columns.insert(thing)
}
If the == operator on Column doesn't care about cells (i.e. adding cells to a column doesn't suddenly make two originally equal columns unequal and vice versa), then you could use update instead:
if var thing = columns.first(
where: {
$0.header.last == Character(String(i))
}) {
thing.cells.append(value: addValue)
columns.update(thing)
}
As you can see, it's quite a lot of work, so maybe sets aren't a suitable data structure to use in this situation. Have you considered using an array instead? :)
private var _columns: [Column]
public var columns : [Column] {
get { _columns }
set { _columns = Array(Set(newValue)) }
// or any other way to remove duplicate as described here: https://stackoverflow.com/questions/25738817/removing-duplicate-elements-from-an-array-in-swift
}
You are getting the error because columns might be a set of struct. So columns.first will give you an immutable value. If you were to use a class, you will get a mutable result from columns.first and your code will work as expected.
Otherwise, you will have to do as explained by #Sweeper in his answer.
What does it mean in Coffeescript when a variable name begins with an "#" sign?
For example, I've been looking through the hubot source code and just in the first few lines I've looked at, I found
class Brain extends EventEmitter
# Represents somewhat persistent storage for the robot. Extend this.
#
# Returns a new Brain with no external storage.
constructor: (robot) ->
#data =
users: { }
_private: { }
#autoSave = true
robot.on "running", =>
#resetSaveInterval 5
I've seen it several other places, but I haven't been able to guess what it means.
The # symbol is a shorcut for this as you can see in Operators and Aliases.
As a shortcut for this.property, you can use #property.
It basically means that the “#” variables are instance variables of the class, that is, class members. Which souldn't be confused with class variables, that you can compare to static members.
Also, you can think of #variables as the this or self operators of OOP languages, but it's not the exact same thing as the old javascript this. That javascript this refer to the current scope, which causes some problems when your are trying to refer to the class scope inside a callback for example, that's why coffescript have introduced the #variables, to solve this kind of problem.
For example, consider the following code:
Brain.prototype = new EventEmitter();
function Brain(robot){
// Represents somewhat persistent storage for the robot. Extend this.
//
// Returns a new Brain with no external storage.
this.data = {
users: { },
_private: { }
};
this.autoSave = true;
var self = this;
robot.on('running', fucntion myCallback() {
// here is the problem, if you try to call `this` here
// it will refer to the `myCallback` instead of the parent
// this.resetSaveInterval(5);
// therefore you have to use the cached `self` way
// which coffeescript solved using #variables
self.resetSaveInterval(5);
});
}
Final thought, the # these days means that you are referring to the class instance (i.e., this or self). So, #data basically means this.data, so, without the #, it would refer to any visible variable data on scope.
I am currently using ReSharper V8.1. I've only recently began using ReSharper and have found some interest in their LiveTemplate Macros. I've conjured up a solution to return a list of HotspotItems from a constant, similar to ReSharper's predefined macro "Comma-delimited list of values". In the method I take the constant variable of the template parameter and do a split string on them to provide a collection of HotSpotItems. Unfortunately it doesn't work if I use the macro more than one time within a template. Below is an extreme hack job showing my implementation of the method HotspotItems of IMacroImplementation.
I am hoping that someone out there may have done some work in this area and could possibly provide an example of how they've implemented IMacroImplementation which provides a list of items from a constant and also allows for multiple uses within a single template.
Thank you.
public override HotspotItems GetLookupItems(IHotspotContext context)
{
HotspotItems hotSpotItems = null;
foreach (var hotspot in context.HotspotSession.Hotspots)
{
if (hotspot.Expression != null && ((MacroCallExpressionNew)hotspot.Expression).Definition is Macros.DisplayMultipleItems)
{
//hotspot.CurrentValue
var multiItems = ((MacroCallExpressionNew) hotspot.Expression).Definition as DisplayMultipleItems;
if (!multiItems.ItemSet)
{
var expression = hotspot.Expression as MacroCallExpressionNew;
IMacroParameterValueNew baseValue = expression.Parameters[0].GetValue(context.SessionContext.Solution.GetLifetime(), context.HotspotSession);
string templateValue = baseValue.GetValue();
multiItems.ItemSet = true;
if (!string.IsNullOrEmpty(templateValue) && templateValue.Split(',').Any())
{
var lookupItems = templateValue.Split(',').Select(param => new TextLookupItem(param)).Cast<ILookupItem>().ToList();
if (hotSpotItems == null)
hotSpotItems = new HotspotItems(lookupItems);
else
{
foreach (var item in lookupItems)
{
hotSpotItems.Items.Add(item);
}
}
}
}
}
}
return hotSpotItems;
}
You should fire up dotPeek and point it to the ReSharper bin directory and take a look at ListMacroDef and ListMacroImpl, which is the implementation for the comma-delimited list macro.
The definition derives from SimpleMacroDefinition. It gets given the parameters in the call to GetPlaceholder, looks at the first and splits it by comma, returning the first item as the placeholder.
ListMacroImpl is just as simple. Its constructor has an [Optional] parameter of type MacroParameterValueCollection. This is the list of parameter values specified in the hotspot editor. You'll want to check for null and take the first parameter, which will be your delimited list. It then overrides GetLookupItems and returns HotspotItems.Empty if the parameter value is null, or parses the value and returns a list of TextLookupItem.
You don't need to look at the session and list of hotspots - that will get you all hotspots in the session, when you're only interested in the current hotspot, and ReSharper will create a new IMacroImplementation for each hotspot and give you those values in your constructor.