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Convert a List<T> to a nested Dictionary<string, Dictionary<string, T>

I'm stuck on a basic problem. I need to convert a flat List to a Nested dictionary of type Dictionary<string,Dictionary<string,Dictionary<string,Dictionary<string,string>>>>
I've almost done except the fact that I need to group multiple properties, and I used an anonymous type for that. Here is an example :
List<ApprovalAction> Gen()
{
return new List<ApprovalAction>
{
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Homeworking", ParameterName = "to", ParameterValue="Approver" },
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Homeworking", ParameterName="subject", ParameterValue = "Aproval Request" },
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Homeworking", ParameterName="body", ParameterValue = "I would like an approval request"},
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Absence", ParameterName="to" , ParameterValue="Approver" },
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Absence", ParameterName="subject", ParameterValue = "Aproval Request" },
new ApprovalAction { Name = "SendMailToApprover", Step="New", ApprovalRequestType = "Absence", ParameterName="body", ParameterValue = "I would like an approval request"}
};
}
var actions = Gen();
var dico = actions
.GroupBy(x => x.ApprovalRequestType)
.ToDictionary(
gdc => gdc.Key,
gdc => gdc.GroupBy(a => a.Step)
.ToDictionary(dd => dd.Key, dd => dd.GroupBy(x => new { x.Name, x.Step, x.ApprovalRequestType }, (key, group) => new
{
Key = key.Name,
Result = group.ToDictionary(k => k.ParameterName, v => v.ParameterValue)
})));
This is the output of Linqpad :
Do you know by which code I can replace to avoid the IEnumerable ?
Thank you !

IEnumerable<> comes from the final GroupBy. If you know that the innermost group would contain exactly one item, use Single(). Otherwise use First():
var dico = actions
.GroupBy(x => x.ApprovalRequestType)
.ToDictionary(
gdc => gdc.Key,
gdc => gdc.GroupBy(a => a.Step)
.ToDictionary(dd => dd.Key, dd => dd.GroupBy(x => new { x.Name, x.Step, x.ApprovalRequestType }, (key, group) => new {
Key = key.Name,
Result = group.ToDictionary(k => k.ParameterName, v => v.ParameterValue)
}).First()
)
);
Result of the query above looks like this:

LINQ expressions for Elasticsearch NEST query

I setting up an index as below. But now I have a requirement because of which i need to tweak the indexing style. (i have to add analyzer field in the below code).
Reference[My previous question and its answer]: Elastic Search using NEST - Results different in debug and browser mode
How can I rewrite
var connectionSettings = new ConnectionSettings(pool)
.DefaultIndex(defaultIndex)
.MapDefaultTypeNames(m => m.Add(typeof(Class1), "omg"))
.PrettyJson()
.DisableDirectStreaming());
with the mapping settings like below.
{
"mappings": {
"Class1": {
"properties": {
"Answer": {
"type": "string",
"analyzer": "english"
}
}
}
}
}
This is my take on answer:
settings = new ConnectionSettings(pool)
.DefaultIndex(defaultIndex)
.MapDefaultTypeNames(m => m.Add(typeof(Class1), "omg"))
.PrettyJson()
.DisableDirectStreaming();
var descriptor = new CreateIndexDescriptor(defaultIndex)
.Mappings(ms => ms
.Map<Class1>(m => m
.Properties(ps => ps
.String(s=>s
.Name(n=>n.Ans)
.Analyzer("english")))));
I think I'm missing a link somewhere between the index creation and mappings. Though it didnt show an error while coding, the output is not as expected.
TIA

A CreateIndexDecriptor<T> is a descriptor for creating an index, but you need to pass it to the IElasticClient.CreateIndex() method in order to create the index in Elasticsearch.
void Main()
{
var defaultIndex = "default-index";
var pool = new SingleNodeConnectionPool(new Uri("http://localhost:9200"));
var settings = new ConnectionSettings(pool, new InMemoryConnection())
.DefaultIndex(defaultIndex)
.MapDefaultTypeNames(m => m.Add(typeof(Class1), "omg"))
.PrettyJson()
.DisableDirectStreaming();
var client = new ElasticClient(settings);
client.CreateIndex("new-index", c => c
.Mappings(ms => ms
.Map<Class1>(m => m
.Properties(ps => ps
.String(s => s
.Name(n => n.Ans)
.Analyzer("english")
)
)
)
)
);
}
public class Class1
{
public string Ans { get; set;}
}
The request to Elasticsearch looks like
{
"mappings": {
"omg": {
"properties": {
"ans": {
"type": "string",
"analyzer": "english"
}
}
}
}
}

Elasticsearch nest can't find filter

So I'm trying to configure my index to have certain mappings and filters, but whenever I try to create the index I get the following error:
"[amgindex] failed to create index]; nested: IllegalArgumentException[Custom Analyzer [amgsearch] failed to find filter under name [synonym]"
this is the code I'm using to create the index
public void newIndex() {
var amgBasic = new CustomAnalyzer {
Tokenizer = "edgeNGram",
Filter = new string[] { "lowercase", "worddelimiter", "stemmerEng", "stemmerNl", "stopper", "snowball" } //
};
var amgBasicText = new CustomAnalyzer {
Tokenizer = "standard",
Filter = new string[] { "lowercase", "worddelimiter" }
};
var amgSearch = new CustomAnalyzer {
Tokenizer = "whitespace",
Filter = new string[] { "lowercase", "synonym" }
};
var synonmyfilter = new SynonymTokenFilter() {
Format = "Solr",
SynonymsPath = "analysis/synonym.txt"
};
try {
var result = client.CreateIndex("amgindex", i => i
.Analysis(descriptor => descriptor
.Analyzers(bases => bases
//.Add("amgBasic", amgBasic)
//.Add("amgBasicText", amgBasicText)
.Add("amgsearch", amgSearch)
)
.TokenFilters(c => c.Add("stemmereng", new StemmerTokenFilter() { Language = "english" }))
.TokenFilters(c => c.Add("stemmernl", new StemmerTokenFilter() { Language = "english" }))
.TokenFilters(c => c.Add("stopper", new StopTokenFilter() { Stopwords = new List<string>() { "_english_", "_dutch_" } }))
.TokenFilters(c => c.Add("snowball", new SnowballTokenFilter() { Language = "english" }))
.TokenFilters(c => c.Add("worddelimiter ", new WordDelimiterTokenFilter() { }))
.TokenFilters(c => c.Add("synonym ", synonmyfilter))
)
.AddMapping<general_document>(m => m
.Properties(o => o
.String(p => p.Name(x => x.object_name).IndexAnalyzer("amgSearch"))
.String(p => p.Name(x => x.title).IndexAnalyzer("amgSearch"))
.String(p => p.Name(x => x.Text).IndexAnalyzer("amgSearch"))
)
)
);
Log.Info("Index created? " + result.Acknowledged);
} catch (Exception ex) {
Log.Error("[index-creation] " + ex.Message);
throw;
}
}
everytime I use one of my own filters the error pops up.
Any clue why this is happening?

After spending way to much time on this I found it!! :)
there was a space in the name of 2 Filters, and those were causing the issue;
▼
.TokenFilters(c => c.Add("worddelimiter ", new WordDelimiterTokenFilter() { }))
▼
.TokenFilters(c => c.Add("synonym ", synonmyfilter))

Elasticsearch.NET NEST Object Initializer syntax for a highlight request

I've got:
var result = _client.Search<ElasticFilm>(new SearchRequest("blaindex", "blatype")
{
From = 0,
Size = 100,
Query = titleQuery || pdfQuery,
Source = new SourceFilter
{
Include = new []
{
Property.Path<ElasticFilm>(p => p.Url),
Property.Path<ElasticFilm>(p => p.Title),
Property.Path<ElasticFilm>(p => p.Language),
Property.Path<ElasticFilm>(p => p.Details),
Property.Path<ElasticFilm>(p => p.Id)
}
},
Timeout = "20000"
});
And I'm trying to add a highlighter filter but I'm not that familiar with the Object Initializer (OIS) C# syntax. I've checked NEST official pages and SO but can't seem to return any results for specifically the (OIS).
I can see the Highlight property in the Nest.SearchRequest class but I'm not experienced enough (I guess) to simply construct what I need from there - some examples and explanations as to how to employ a highlighter with OIS would be hot!

This is the fluent syntax:
var response= client.Search<Document>(s => s
.Query(q => q.Match(m => m.OnField(f => f.Name).Query("test")))
.Highlight(h => h.OnFields(fields => fields.OnField(f => f.Name).PreTags("<tag>").PostTags("</tag>"))));
and this is by object initialization:
var searchRequest = new SearchRequest
{
Query = new QueryContainer(new MatchQuery{Field = Property.Path<Document>(p => p.Name), Query = "test"}),
Highlight = new HighlightRequest
{
Fields = new FluentDictionary<PropertyPathMarker, IHighlightField>
{
{
Property.Path<Document>(p => p.Name),
new HighlightField {PreTags = new List<string> {"<tag>"}, PostTags = new List<string> {"</tag>"}}
}
}
}
};
var searchResponse = client.Search<Document>(searchRequest);
UPDATE
NEST 7.x syntax:
var searchQuery = new SearchRequest
{
Highlight = new Highlight
{
Fields = new FluentDictionary<Field, IHighlightField>()
.Add(Nest.Infer.Field<Document>(d => d.Name),
new HighlightField {PreTags = new[] {"<tag>"}, PostTags = new[] {"<tag>"}})
}
};
My document class:
public class Document
{
public int Id { get; set; }
public string Name { get; set; }
}

LINQ: ...Where(x => x.Contains(string that start with "foo"))

Given a collection of the following class:
public class Post
{
...
public IList<string> Tags { get; set; }
}
Is there an easy way to get all Posts that contain a tag starting with "foo" using LINQ?
var posts = new List<Post>
{
new Post { Tags = new[] { "fooTag", "tag" }},
new Post { Tags = new[] { "barTag", "anyTag" }},
new Post { Tags = new[] { "someTag", "fooBarTag" }}
};
var postsWithFooTag = posts.Where(x => [some fancy LINQ query here]);
postsWithFooTag should now contain items 1 and 3 of posts.

Use string's StartsWith
var postsWithFooTag = posts.Where(x => x.Tags.Any(y => y.StartsWith("foo")));
x.Any will check if any element matches some condition. StartsWith checks if the element starts with a certain string.
The above returned:
new Post { Tags = new[] { "fooTag", "tag" }},
new Post { Tags = new[] { "someTag", "fooBarTag" }}
To make it case insensitive use StringComparison.OrdinalIgnoreCase.
var postsWithFooTag = posts.Where(x => x.Tags.Any(y => y.StartsWith("FoO", StringComparison.OrdinalIgnoreCase)));
Returns:
new Post { Tags = new[] { "fooTag", "tag" }},
new Post { Tags = new[] { "someTag", "fooBarTag" }}
while StartsWith("FoO") returns no results.

Try this:
var postsWithFooTag = posts.Where(x => x.Tags.Any(y => y.StartsWith("foo")))

I believe this will work for what you're trying to do.
posts.Where(p => p.Tags.Any(t => t.StartsWith("foo")))

var tag = "foo";
var postsWithFooTag =
posts.Where( p=> p.Tags.Any( t => t.StartsWith(tag)));

Try x => x.Tags.Any(tag => tag.StartsWith("foo"))