NRedisStack

JSONPath supports logical operators to combine multiple relational expressions within a filter:

• Logical AND (&&): Both conditions must be true.
• Logical OR (||): At least one condition must be true.

Example of Logical AND:

json.Get("warehouse:1", "$.inventory[?(@.gender==\"Men\"&&@.price>20)]");

Example of Logical OR:

json.Get("warehouse:1", "$.inventory[?(@.price<100||@.gender==\"Women\")].id");

Starting from version 1.0.0-beta1, NRedisStack automatically overrides the server-side dialect to version 2 by default. This means the client automatically appends DIALECT 2 to commands like FT.AGGREGATE and FT.SEARCH.

This change may impact the results returned compared to older versions. If your application requires a different dialect, you must configure the client accordingly.

You can use JSONPath filter expressions [?(<expression>)] to query items within an array based on relational logic. Supported operators include:

• Equality (==): Match a field against a specific value.
• Less Than (<): Match numeric fields less than a value.
• Greater Than or Equal (>=): Match numeric fields greater than or equal to a value.

Example of equality:

// Matches items where description is exactly 'Turtle Check Men Navy Blue Shirt'
json.Get("warehouse:1", "$.inventory[?(@.description==\"Turtle Check Men Navy Blue Shirt\")]");

NRedisStack extends the standard StackExchange.Redis client by providing specialized command classes for different Redis Stack modules.

To use a module, you first connect using the standard StackExchange.Redis ConnectionMultiplexer and obtain an IDatabase. You then access the module-specific commands by calling an extension method on the IDatabase instance (e.g., db.JSON() for JSON commands).

Each module has its own dedicated command class that exposes the relevant Redis Stack commands.

using NRedisStack;
using NRedisStack.RedisStackCommands;
using StackExchange.Redis;

ConnectionMultiplexer redis = ConnectionMultiplexer.Connect("localhost");
IDatabase db = redis.GetDatabase();

// Access module commands via extension methods
JsonCommands json = db.JSON();
SearchCommands ft = db.FT();

Use the =~ operator in a JSONPath filter to perform regular expression matching on string fields.

• Exact Match/Contains: [?(@.field =~ "pattern")] matches if the pattern is found.
• Case Insensitive: Use the (?i) flag within the regex string (e.g., "(?i)term").
• Begins With: Use the ^ anchor (e.g., "^Term").

Examples:

json.Get("warehouse:1", "$.inventory[?(@.description =~ \"Blue\")]");

// Case-insensitive 'watch'
json.Get("warehouse:1", "$.inventory[?(@.description =~ \"(?i)watch\")]");

// Begins with 'T'
json.Get("warehouse:1", "$.inventory[?(@.description =~ \"^T\")]");

All NRedisStack methods provide both synchronous and asynchronous implementations. Asynchronous methods are identified by the Async suffix (e.g., SetAsync, GetAsync) and are fully await-able. To use them, ensure you are working within an async context and await the calls to prevent blocking.

// Connect to a Redis server and get a JSON instance
var redis = await ConnectionMultiplexer.ConnectAsync("localhost");
var db = redis.GetDatabase();
var json = db.JSON();

// Store data asynchronously
await json.SetAsync("key", "$", new { name = "John", age = 30, city = "New York" });

// Retrieve data asynchronously
var john = await json.GetAsync("key");

Combine RediSearch with JSONPath filtering to extract specific nested data from JSON documents.

1. Indexing JSON

Use FT.CREATE with IndexDataType.JSON. Define fields using FieldName with JSONPath syntax (e.g., $.city).

2. Filtering with JSONPath

Use .ReturnFields() in your Query to apply JSONPath filters. This allows you to return only specific elements of an array that match a condition (e.g., $.inventory[?(@.price>50)].id). Use Dialect(3) to ensure full JSONPath support.

foreach (var doc in ft.Search("wh_idx",
                        new Query("@city:Boston")
                            .ReturnFields(new FieldName("$.inventory[?(@.price>50)].id", "result"))
                            .Dialect(3))
                    .Documents.Select(x => x["result']))
{
    Console.WriteLine(doc);
}

To perform advanced operations like Vector Similarity Search, JSON filtering, and Aggregations, you must include the following namespaces in your C# project:

using StackExchange.Redis;
using NRedisStack;
using NRedisStack.RedisStackCommands;
using NRedisStack.Search;
using NRedisStack.Search.Literals.Enums;
using NRedisStack.Search.Aggregation;

The REDUCE COLLECT reducer (used with FT.AGGREGATE and GROUPBY) is currently gated behind the server's unstable features flag. If this flag is not enabled, the server will return an error when attempting to use this feature.

To enable it, you must run the following command on your Redis server:

Note for Clusters: In a Redis Cluster environment, the flag must be enabled on all nodes, not just the coordinator or the node receiving the connection, as the query is fanned out to every shard.

CONFIG SET search-enable-unstable-features yes

To add NRedisStack to your .NET project, use the dotnet CLI to add the NuGet package.

dotnet add package NRedisStack