I have an entity defined as
#code
- #code:type_1 = pattern 'Y(\d{3})'
- #code:type_2 = pattern 'order number(\d{3})'
- #code:type_3 = pattern 'CZ(\d{3})'
I am trying to capture the following context values like so
{
"context": {
"type_3s": "<? #code.filter(\"c\", \"c['value'] == 'type_3'\").joinToArray('%e.groups[1]%') ?>"
}
}
So that for input
Please delete codes CZ123, CZ456, and CZ789, my final context looks like this:
$type_3s =[123,456,789]
Currently getting the error
SpEL evaluation error: Expression [ entities['code'].filter("c", "c['value'] == 'type_3'").joinToArray('%e.groups[1]%') ] at position 63: EL1004E: Method call: Method joinToArray(String) cannot be found on ArrayList type
In the above example, code.values evaluates to:
#code.values =["type_3", "type_3", "type_3"]
Any help in achieving the desired context would be greatly appreciated, thank you so much!
My recommendation would be to take a look at the Watson Assistant entity syntax. .value returns the identified entity which would be type_3. You would need to use .literal to access what was really entered.
In the tutorial on building a database-driven Slackbot a similar method is used to access what was entered for a location entity. The code is on GitHub.
Related
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
I'm trying to extract the parameter from a Lift Menu.param within a snippet so that I can use it to create a named Comet. However, I get a NullPointerException when I try to pass the parameter to the snippet using SnippetDisptach in my Boot.scala, as suggested here:
http://comments.gmane.org/gmane.comp.web.lift/44299
I've created the Menu item as follows:
object AnItemPage {
// create a parameterized page
def menu = Menu.param[Item]("Item", "Item",
s => fetchItem(s), item => item._id.toString) / "item"
private def fetchItem(s:String) : Box[Item] = synchronized {
ItemDAO.findById(ObjectId.massageToObjectId(s))
}
}
I've added the menu to SiteMap. I've also created a Snippet which I would like to pick up the Item parameter. (I'm using fmpwizard's InsertNamedComet library here):
class AddCometItemPage(boxedItem: Box[Item]) extends InsertNamedComet with DispatchSnippet{
val item : Item = boxedItem.openOr(null)
override lazy val name= "comet_item_" + item._id.toString
override lazy val cometClass= "UserItemCometActor"
def dispatch = null
}
My next step is to crate an instance of this class as demonstrated by David Pollak here:
http://comments.gmane.org/gmane.comp.web.lift/44299
This is what I have added to my Boot.scala:
LiftRules.snippetDispatch.append {
case "item_page" => new AddCometItemPage(AnItemPage.menu.currentValue)
}
My item.html references this snippet:
<div class="lift:item_page">
I get the following null pointer exception when I compile and run this:
Exception occurred while processing /item/5114eb4044ae953cf863b786
Message: java.lang.NullPointerException
net.liftweb.sitemap.Loc$class.siteMap(Loc.scala:147)
net.liftweb.sitemap.Menu$ParamMenuable$$anon$9.siteMap(Menu.scala:170)
net.liftweb.sitemap.Loc$class.allParams(Loc.scala:123)
net.liftweb.sitemap.Menu$ParamMenuable$$anon$9.allParams(Menu.scala:170)
net.liftweb.sitemap.Loc$class.net$liftweb$sitemap$Loc$$staticValue(Loc.scala:87)
net.liftweb.sitemap.Menu$ParamMenuable$$anon$9.net$liftweb$sitemap$Loc$$staticValue(Menu.scala:170)
net.liftweb.sitemap.Loc$$anonfun$paramValue$2.apply(Loc.scala:85)
net.liftweb.sitemap.Loc$$anonfun$paramValue$2.apply(Loc.scala:85)
net.liftweb.common.EmptyBox.or(Box.scala:646)
net.liftweb.sitemap.Loc$class.paramValue(Loc.scala:85)
net.liftweb.sitemap.Menu$ParamMenuable$$anon$9.paramValue(Menu.scala:170)
net.liftweb.sitemap.Loc$$anonfun$currentValue$3.apply(Loc.scala:114)
net.liftweb.sitemap.Loc$$anonfun$currentValue$3.apply(Loc.scala:114)
net.liftweb.common.EmptyBox.or(Box.scala:646)
net.liftweb.sitemap.Loc$class.currentValue(Loc.scala:114)
net.liftweb.sitemap.Menu$ParamMenuable$$anon$9.currentValue(Menu.scala:170)
bootstrap.liftweb.Boot$$anonfun$lift$8.apply(Boot.scala:107)
bootstrap.liftweb.Boot$$anonfun$lift$8.apply(Boot.scala:106)
net.liftweb.util.NamedPF$$anonfun$applyBox$1.apply(NamedPartialFunction.scala:97)
net.liftweb.util.NamedPF$$anonfun$applyBox$1.apply(NamedPartialFunction.scala:97)
net.liftweb.common.Full.map(Box.scala:553)
net.liftweb.util.NamedPF$.applyBox(NamedPartialFunction.scala:97)
net.liftweb.http.LiftRules.snippet(LiftRules.scala:711)
net.liftweb.http.LiftSession$$anonfun$net$liftweb$http$LiftSession$$findSnippetInstance$1.apply(LiftSession.scala:1506)
net.liftweb.http.LiftSession$$anonfun$net$liftweb$http$LiftSession$$findSnippetInstance$1.apply(LiftSession.scala:1506)
net.liftweb.common.EmptyBox.or(Box.scala:646)
net.liftweb.http.LiftSession.net$liftweb$http$LiftSession$$findSnippetInstance(LiftSession.scala:1505)
net.liftweb.http.LiftSession$$anonfun$locateAndCacheSnippet$1$1$$anonfun$apply$88.apply(LiftSession.scala:1670)
net.liftweb.http.LiftSession$$anonfun$locateAndCacheSnippet$1$1$$anonfun$apply$88.apply(LiftSession.scala:1669)
Has anybody any idea where I'm going wrong? I've not been able to find a lot of information on Menu.param.
Thank you very much for your help.
f
I have never tried what you are doing, so I am not sure the best way to accomplish it. The way you are using the Loc Param, you are extracting a variable from a URL pattern. In your case, http://server/item/ITEMID where ITEMID is the string representation of an Item, and which is the value that gets passed to the fetchItem function. The function call will not have a value if you just arbitrarily call it, and from what I can see you are requesting a value that is not initialized.
I would think there are two possible solutions. The first would be to use S.location instead of AnItemPage.menu.currentValue. It will return a Box[Loc[Any]] representing the Loc that is currently being accessed (with the parameters set). You can use that Loc to retrive currentValue and set your parameter.
The other option would be to instantiate the actor in your snippet. Something like this:
item.html
<div data-lift="AnItemPage">
<div id="mycomet"></div>
</div>
And then in your AnItemPage snippet, something like this:
class AnItemPage(item: Item) {
def render = "#mycomet" #> new AddCometItemPage(item).render
}
I haven't tested either of those, so they'll probably need some tweaking. Hopefully it will give you a general idea.
I'm trying to replace a function call like (simplified) Utility.GetString(MyEntity.SomePropertyWithRelatedEntity)=="abc" with an expression visitor into something like p => p.SubRelatedEntities.FirstOrDefault(sre => sre.SomeFlag==true).SomePropertyWithRelatedEntity.
It means, the datamodel goes like:
MyEntity -> RelatedEntity -> SubRelatedEntity
I'm trying to return a string value from the SubRelatedEntity, based on some rules in the RelatedEntity, so I don't have to re-write / copy/paste the whole filtering rules in every usage; that's why I put inside a "call-signature", so my expression visitor can identify it and replace the fake-call to Utility.GetString to some complicated lambda expressions.
My expression visitor contains something like:
public override Expression Visit(Expression node)
{
if (node == null)
return null;
Expression result = null;
if (node.NodeType == ExpressionType.Call)
{
MethodCallExpression mce = node as MethodCallExpression;
if (mce.Method.DeclaringType == typeof(Utility) && mce.Method.Name == "GetString")
{
Expression<Func<RelatedEntity, string>> exp = re => re.SubRelatedEntities.FirstOrDefault(sre => sre.SomeFlag == true).SomeStringValue;
result = exp.Body;
}
else
result = base.Visit(node);
}
else
result = base.Visit(node);
return result;
}
Now, the problem is, the "sre" parameter is not bound when called the injected lambda expression. After much research, I see the lambda parameters should be replaced with another expression visitor, specifically searching for the new parameters and replacing them with the old ones. In my situation, however, I don't have an "old parameter" - I have the expression MyEntity.SomePropertyWithRelatedEntity (e.g. an property filled with the related entities) which I need to insert somehow in the generated lambda.
I hope my problem is understandable. Thank you for any insights!
After getting no answers for long time and trying hard to find a solution, I've solved it at the end :o)! It goes like this:
The newly injected lambda expression gets an ParameterExpression - well, this is a 'helper', used when directly calling the lambda, what I don't want (hence, 'parameter not bound' exception when ToEnumerable is called). So, the clue is to make a specialized ExpressionVisitor, which replaces this helper with the original expression, which is of course available in the Arguments[] for the method call, which I try to replace.
Works like a charm, like this you can reuse the same LINQ expressions, something like reusable sub-queries, instead of writing all the same LINQ stuff all time. Notice as well, that expression calling a method is not allowed in EF, in Linq2Sql it worked. Also, all the proposed web articles only replace the parameter instances, when constructing/merging more LINQ expressions together - here, I needed to replace a parameter with an faked-method-call argument, e.g. the method should not be called, it only stands for a code-marker, where I need to put my LINQ sub-query.
Hope this helps somebody, at the end it's pretty simple and logical, when one knows how the expression trees are constructed ;-).
Bye,
Andrej
I've just started using Lambda expressions, and really like the shortcut. I also like the fact that I have scope within the lambda of the encompassing method. One thing I am having trouble with is nesting lambdas. Here is what I am trying to do:
public void DoSomeWork()
{
MyContext context = new MyDomainContext();
context.GetDocumentTypeCount(ci.CustomerId, io =>
{
if (io.HasError)
{
// Handle error
}
// Do some work here
// ...
// make DB call to get data
EntityQuery<AppliedGlobalFilter> query =
from a in context.GetAppliedGlobalFiltersQuery()
where a.CustomerId == ci.CustomerId && a.FilterId == 1
select a;
context.Load<AppliedGlobalFilter>(query, lo =>
{
if (lo.HasError)
{
}
**// Do more work in this nested lambda.
// Get compile time error here**
}
}, null);
}, null);
}
The second lambda is where I get the following compile time error:
Cannot convert Lambda expression to type 'System.ServiceModel.DomainService.Client.LoadBehavior' because it is not a delegate type
The compiler is choosing the wrong overload for the Load method even though I am using the same override I did in the previous Lambda.
Is this because I am trying to nest? Or do I have something else wrong?
Thanks,
-Scott
Found the problem as described in my comment above. I'll head back to work now - red face and all....
I realize this is not the answer you want, but I suggest caution about lengthy and/or nested lambdas. They work, but they often make code harder to read / maintain by other developers. I try to limit my lambdas in length to three statements, with no nesting.
I'm implementing a search box using CodeIgniter, but I'm not sure about how I should pass the search parameters through. I have three parameters: the search string; product category; and the sort order. They're all optional. Currently, I'm sending the parameters through $_POST to a temporary method, which forwards the parameters to the regular URI form. This works fine. I'm using a weird URI format though:
http://site.com/products/search=computer,sort=price,cat=laptop
Does anyone have a better/cleaner format of passing stuff through?
I was thinking of passing it into the products method as arguments, but since the parameters are optional things would get messy. Should I suck it up, and just turn $_GET methods on? Thanks in advance!
Query Strings
You can enable query strings in CodeIgniter to allow a more standard search function.
Config.php
$config['enable_query_strings'] = FALSE;
Once enabled, you can accept the following in your app:
http://site.com/products/search?term=computer&sort=price&cat=laptop
The benefit here is that the user will find it easy to edit the URL to make a quick change to their search, and your search uses common search functionality.
The down side of this approach is that you are going against one of the design decisions of the CodeIgniter development team. However, my personal opinion is that this is OK provided that query strings are not used for the bulk of your content, only for special cases such as search queries.
A much better approach, and the method the CI developers intended, is to add all your search parameters to the URI instead of a query string like so:
http://site.com/products/search/term/computer/sort/price/cat/laptop
You would then parse all the URI segments from the 3rd segment ("term") forward into an array of key => value pairs with the uri_to_assoc($segment) function from the URI Class.
Class Products extends Controller {
...
// From your code I assume you are calling a search method.
function search()
{
// Get search parameters from URI.
// URI Class is initialized by the system automatically.
$data->search_params = $this->uri->uri_to_assoc(3);
...
}
...
}
This would give you easy access to all the search parameters and they could be in any order in the URI, just like a traditional query string.
$data->search_params would now contain an array of your URI segments:
Array
(
[term] => computer
[sort] => price
[cat] => laptop
)
Read more about the URI Class here: http://codeigniter.com/user_guide/libraries/uri.html
If you're using a fixed number of parameters, you can assign a default value to them and send it instead of not sending the parameter at all. For instance
http://site.com/products/search/all/somevalue/all
Next, in the controller you can ignore the parameter if (parameter == 'all'.)
Class Products extends Controller {
...
// From your code I assume that this your structure.
function index ($search = 'all', $sort = 'price', $cat = 'all')
{
if ('all' == $search)
{
// don't use this parameter
}
// or
if ('all' != $cat)
{
// use this parameter
}
...
}
...
}