I am using neo4j 1.9.4 community and soon will upgrade to 2.x. I know that neo4j can be configured with timeout in 2 ways as described here
But I wanna know if the second approach i.e. including max-execution-timeout in REST call header is supported by any of the Neo4jClient method so that I can pass that value as a parameter before returning my results? Also, will it be supported by future neo4j release?
The goal is to define a timeout for each query rather global setting.
Something like :
GraphClient
.Root
.StartCypher("root")
.Match("root-[:HAS]->childs")
.Return("childs")
.Results(5000) // passing timeout value in ms
At present, no, Neo4jClient doesn't have this capability.
Will it be supported? That depends on a few things, but as it's open source (https://github.com/Readify/Neo4jClient) you can always add it yourself and get it into the next release.
PS. For using against a 2.x db, you will want to look at the .Cypher so your query will look more like:
GraphClient.Cypher
.Match("root-[:HAS]->child")
.Return(child => child.As<ChildObj>())
.Results();
Related
Need to execute and return 1st order detail alone for each order. Below doesn't work
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?$expand=Orders($expand=Order_Details;$top=1)
Need to filter records based on order id. Below doesn't work and throws "Term 'Orders($expand=Order_Details)$filter=OrderID eq '10643'' is not valid in a $select or $expand expression"
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?$expand=Orders($expand=Order_Details)$filter=OrderID eq '10643'
Invalid but returned results
https://services.odata.org/Experimental/Northwind/Northwind.svc/Regions?expand=Order_Details
https://services.odata.org/Experimental/Northwind/Northwind.svc/Regions?expand=Territories
Not Returning Childrens
https://services.odata.org/Experimental/Northwind/Northwind.svc/Products?&expand=Suppliers
https://services.odata.org/Experimental/Northwind/Northwind.svc/Regions?&expand=Territories
https://services.odata.org/Experimental/Northwind is no longer 'Best Practise'
It's a bold statement, but this question proves that many advanced query features have not been fully or properly implemented in the published service.
While many developers may use it to practise OData query concepts, given that the OData implementation is largely up to the developers and the version of the packages they use, it is probably a of more commercial value if you query against a live or a dev implementation of the actual service that you want to query.
The following is an analysis of OPs queries and how to achieve the desired response according the the OData-V4 specification and verified against a deployed API that utilises the following NuGet packages:
Microsoft.AspNet.OData v7.3.0
Microsoft.OData.Core v7.6.2
The actual API that I used for testing is proprietary and cannot be published here.
According to the spec, you have to move the $top specifier to the Order_Details expansion.
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?
$expand=Orders($expand=Order_Details($top=1))
However:
https://services.odata.org/Experimental/Northwind does not correctly implement $top query option within expansion as defined in 5.1.3 System Query Option $expand
Query options can be applied to an expanded navigation property by appending a semicolon-separated list of query options, enclosed in parentheses, to the navigation property name. Allowed system query options are $filter, $select, $orderby, $skip, $top, $count, $search, and $expand.
$top is however supported in the ODataLib v7+ (.Net) implementation of OData v4. So the syntax is correct, but you should check with your API developers for their opinion if your queries with this syntax do not work.
NOTE: When using $top you should also use $orderbyto ensure that the query results are reliable and reproducable:
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?
$expand=Orders($expand=Order_Details($orderby=ProductID;$top=1))
To apply multiple query options within an expansion, you must separate then with a semi-colon: ;. However that alone will not prevent other customer records from being returned, so you must also add a root level filter as well, which is complicated by the fact that Orders is a collection. We can use the any function to only return customers that have an order with the specified Id:
Also note that OrderID is numeric, so do not wrap comparison values in quotes
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?
$expand=Orders($expand=Order_Details;$filter=OrderID eq 10643)
&$filter=Orders/any(o:o/OrderID eq 10643)
this can be further simplified using parameter alias:
https://services.odata.org/Experimental/Northwind/Northwind.svc/Customers?
$expand=Orders($expand=Order_Details;$filter=OrderID eq #orderId)
&$filter=Orders/any(o:o/OrderID eq #orderId)
&#orderId='10643'
However:
https://services.odata.org/Experimental/Northwind does not correctly implement parameter aliases so you cannot verify the alias syntax against this service.
Also note
that experimental service is not correctly applying the filter to either the root elements or the navigation collection, the syntax shown here does however work against the .Net ODataLib implementations of OData v4.
The reason that your $expand is not working is that you have left off the $ from the parameter name. The OData query interpreter only identifies query options are parameters that start with $.
Eitherway, according to the https://services.odata.org/Experimental/Northwind/Northwind.svc/$metadata#Regions, there is no Order_Details navigation property to $expand on:
<EntitySet Name="Regions" EntityType="NorthwindModel.Region">
<NavigationPropertyBinding Path="Territories" Target="Territories" />
</EntitySet>
So when you try again with the correct syntax:
https://services.odata.org/Experimental/Northwind/Northwind.svc/Regions?$expand=Order_Details
you get the expected message:
Could not find a property named 'OrderID' on type 'NorthwindModel.Region'
The second attempt will work if you put the correct $ in there for the $expand query option:
https://services.odata.org/Experimental/Northwind/Northwind.svc/Regions?$expand=Territories
The OData query parser only looks for the expected query options with the $ prefix, this allows your API logic to still process other non-OData parameters as you see fit to do so. The other parameters therefor are still HTTP Url compliant parameters, the implementation at odata.org doesn't know what to do with them and they are simply ignored.
This is just another variation on the same issue with 3, the $ is missing. (I suspect that this URL was meant to be in 3: https://services.odata.org/Experimental/Northwind/Northwind.svc/Products?$expand=Suppliers)
So while https://services.odata.org/Experimental/Northwind is not 100% reliable, neither are the .Net ODataLib, SAP or MS Dynamics implementations. The spec is evolving and there are many query techniques that are not fully implemented in probably any providers at this stage.
Simply be mindful of this fact and when you run into issues using an API, the first point of contact should be the developers or the community that are supporting that particular API, it will be up to the developers what techniques and packages they use and at the end of the day to what extent they support the protocol as it is specified.
First of all please share if there is any MSGraph SDK official documentation anywhere that I can use for reference.
I have a scenario, where I want to query all manager and member links from AAD without providing the user and group objectID respectively. This is currently supported in DQ channel, i.e. I can do something like this using MsGraphSDK:
MsGraphClient.Users.Delta().Request().Select("manager")
OR
MsGraphClient.Groups.Delta().Request().Select("members")
I don't want to use DQ for initial-sync due to performance problems, and other issues.
My fallback option is to query through Graph directly, so I want to do something like the following, but this doesn't return any result:
MsGraphClient.Users.Request().Select("manager")
OR
MsGraphClient.Groups.Request().Select("members")
It looks like this isn't even supported currently at the lower (AADGraph) layer. Please correct me if I am wrong, and provide a solution if any!
So my fallback approach is to pull all the user and group aadObjectIds, and explicitly query the manager and member links respectively.
In my case, there can potentially be 500K User-Objects in AAD, and I want to avoid making 500K separate GetManager calls to AAD. Instead, I want to batch the Graph requests as much as possible.
I wasn't able to find much help from the Internet on sending Batch requests through SDK.
Here's what I am doing:
I have this BatchRequestContent:
var batchRequestContent = new BatchRequestContent();
foreach (string aadObjectId in aadObjectIds)
{
batchRequestContent.AddBatchRequestStep(new BatchRequestStep(aadObjectId, Client.Users[aadObjectId].Manager.Request().GetHttpRequestMessage()));
}
and I am trying to send a BatchRequest through GraphSDK with this content to get a BatchResponse. Is this currently supported in SDK? If yes, then what's the procedure? Any documentation or example? How to read the batch-response back? Finally, is there any limit for the # of requests in a batch?
Thanks,
Here is a related post: $expand=manager does not expand manager
$expand is currently not supported on the manager and directReports relationships in the v1.0 endpoint. It is support in the beta endpoint but
the API returns way to much throw away information: https://graph.microsoft.com/beta/users?$expand=manager
The client library partially supports Batch at this time although we have a couple of pull requests to provide better support
with the next release (PR 1 and 2).
To use batch with the current library and your authenticated client, you'll do something like this:
var authProv = MsGraphClient.AuthenticationProvider;
var httpClient = GraphClientFactory.Create(authProv);
// Send batch request with BatchRequestContent.
HttpResponseMessage response = await httpClient.PostAsync("https://graph.microsoft.com/v1.0/$batch", batchRequestContent);
// Handle http responses using BatchResponseContent.
BatchResponseContent batchResponseContent = new BatchResponseContent(response);
I would like to build an in-memory Lucene index from a collection of node properties and then search against that index.
These search transactions will be happening in parallel, I need to be able to construct a separate search index for each transaction. It seems like this would not be possible using native (manual) Neo4j indexes, since they are "global", hence the use of a memory-based search index, am I mistaken?
This is working great for our use case. A couple of notes:
Use MemoryIndex rather than RAMDirectory.
Be sure to specify "provided" in your dependencies for Lucene.
You can only use 5.5.0, which is what is used natively by Neo4j.
I want to play with neo4j and spacial indexes. I can't find any documentation that demonstrates how to do this through cypher, only through the REST API.
Is it possibly to create spacial indexes through Cypher, say in the neo4j web console?
There is currently no way to create a spatial index using Cypher. You can either use java API or a REST call, see docs at http://neo4j-contrib.github.io/spatial/#rest-api-create-a-spatial-index for details. Since Neo4j browser allows to send HTTP POST you can type there:
:POST /db/data/index/node {"name":"geom", "config":
{"provider":"spatial", "geometry_type":"point", "lat":"lat", "lon":"lon"}
}
Alternatively you can use the index command within neo4j-shell.
Update for Neo4j 3.0
Neo4j Spatial for 3.0 provides stored procedures to manage the spatial index - and therefore everything can be done through cypher. See https://github.com/neo4j-contrib/spatial/blob/master/src/main/java/org/neo4j/gis/spatial/procedures/SpatialProcedures.java.
Note: this version is not yet released, so you have to build from source yourself.
I am trying to learn the OData version 4 protocol and am using the Northwind database to run queries against.
OData 4 introduced the free text search with $search but the queries I've tried all fail.
A couple things I tried (with many variants):
http://services.odata.org/V4/Northwind/Northwind.svc/Customers?$search=%28City%20eq%20Berlin%29
http://services.odata.org/V4/Northwind/Northwind.svc/Customers?$search=City%20eq%20Berlin
http://services.odata.org/V4/Northwind/Northwind.svc/Customers?$search=Berlin
Error message I get is: The query parameter '$search' begins with a system-reserved '$' character but is not recognized.
The official docs don't say much here, and just reference another source for the exact format. However, the format is very cryptic to me...
From the docs, the general idea is http://host/service/Products?$search=blue OR green which seems in line with my examples. So not sure what I'm doing wrong here.
Has anyone successfully used this before and could give me an example? Thanks!
You got an error message from http://services.odata.org/V4/Northwind/Northwind.svc because this service has not been updated to support $search. ODL began to support $search in version 6.1.0. please check 6.1.0 release notes
From the spec, "The $search system query option restricts the result to include only those entities matching the specified search expression. The definition of what it means to match is dependent upon the implementation." Since the match rule is dependent on the service implementation, the service can determine which property or even properties combinations to match the search expression.
This service http://odatae2etest.azurewebsites.net/demo/DefaultService/ has simply implemented $search, and this service choose to have the first string type property to match the search expression.
So for this service, http://odatae2etest.azurewebsites.net/demo/DefaultService/ProductDetails?$search=snack is actually meant to return ProductDetails whose description contains 'snack'.
Otherwise, $search supports AND, OR, NOT operations.