redis-com-client

This is a fork of redis-com-client by Diego Koga.

It allows you to connect to a Redis Server from Classic ASP, other COM+ clients should also be able to connect to Redis using the provided DDLs, but that is untested.

Using this software you can use Redis in Classic ASP for caching, session management, or just storing key-value pairs in an efficient, fast way.

This fork was made to support more Redis commands, and to continue the development of the ASP COM interface for Redis. Another important change is that with this fork it's possible to provide a configurationstring for connecting to different Redis servers across a network, instead of only to localhost. Examples of these configurationstrings can be found here:https://stackexchange.github.io/StackExchange.Redis/Configuration.html#basic-configuration-strings

Installation

You can either compile the redis-com-client dll yourself using Visual Studio, or use the precompiled dll and its dependencies, found in the Precompiled DLLs folder.

Copy the dll and its dependencies to a directory somewhere the application pool of your classic ASP application has rights. Then register the main redis-com-client.dll. The COM+ dll is 64 bit, so it requires the 64-bit regasm.exe to install.

%SystemRoot%\Microsoft.NET\Framework64\v4.0.30319\regasm redis-com-client.dll /tlb:redis-com-client.tlb /codebase

Again, make sure the application pool for your ASP site has rights to the directory that contains the dll, and that the depedencies are next to the redis-com-client.dll.

Usage

In ASP the client can be used like this:

Set Redis = Server.CreateObject("RedisComClient")
    ' Pass in a configuration to connect to a server
    Redis.Open("localhost")

    ' SetPermanent gives a key an indefinite TTL...
    call Redis.SetPermanent("key1", "abcde")
    Response.Write("Key1 = " & Redis.Get("key1") & "<br/>")

    ' ...but you can always change the TTL later
    call Redis.Expire("key1", 60)
    Response.Write("Key1 TTL = " & Redis.TTL("key1") & "<br/>")

    ' Or delete it alltogether
    Redis.Del("key1")
    Response.Write("Key1 is now gone... " & Redis("key1") & "<br/>")

    ' The key "stringkey" will have a TTL of 10 seconds
    call Redis.Set("stringkey", "abcde", 10)

    ' We can also put keys and values in hashes...
    call Redis.Hset("testhash", "firstfield", "firstvalue")
    call Redis.Hset("testhash", "secondfield", "secondvalue")
    Response.Write("Testhash[firstfield] = " & Redis.Hget("testhash", "firstfield") & "<br/>")
    Response.Write("Testhash[secondfield] = " & Redis.Hget("testhash", "secondfield") & "<br/>")

    ' ...and expire the entire hash
    call Redis.Expire("testhash", 60)
    Response.Write("Testhash will expire in 60 seconds. The TTL is:" & Redis.TTL("testhash") & "<br/>")
    dim result : result = Redis.Hget("testhash", "firstfield")
    Response.Write("Here is our Testhash[firstfield] again:" & result & "<br/>")

    ' Or delete a complete hash in one go
    Redis.Del("testhash")
    Response.Write("Testhash is now gone...<br/>")
Set Redis = Nothing

API

Open(string configurationstring)

Opens the connection to a Redis server using a configuration string. Configuration strings are described here: https://stackexchange.github.io/StackExchange.Redis/Configuration.html#basic-configuration-strings

Del(string key)

Deletes a key from the server

bool Exists(string key)

Checks if a key by that name exists. Returns true or false.

ExpireAt(string key, DateTime ExpireDatetime)

Expires a key at a specific date and time

Expire(string key, int seconds)

Expires a key in the given amount of seconds

int TTL(string key)

Returns the TTL (time to live) of a key in seconds

object Get(string key)

Returns the value of a key

Set(string key, object value, int SecondsToExpire)

Sets the value of a key and the TTL in seconds

SetPermanent(string key, object value)

Sets the value of a key. The TTL will be set to -1, which means the key will be available permanently.

Persist(string key)

Sets a key to be permanently available

string Type(string key)

Returns the type of a key. For example 'string'.

double Decr(string key)

Decrements the value of the given key by 1. This key should hold an integer or a double value. Returns the resulting value.

double DecrBy(string key, double decrement)

Decrements the value of the given key by a given number. This key should hold an integer or a double value.Returns the resulting value.

double Incr(string key)

Increments the value of the given key by 1. This key should hold an integer or a double value.Returns the resulting value.

double IncrBy(string key, double increment)

Increments the value of the given key by a given number. This key should hold an integer or a double value.Returns the resulting value.

Hdel(string key, string field)

Deletes a specified field in a hash

bool Hexists(string key, string field)

Checks if a specified field in a hash exists. Returns true or false.

object Hget(string key, string field)

Returns the value of a field in a hash

long Hlen(string key)

Returns the number of fields in a hash

bool Hset(string key, string field, string value)

Sets the value of a field in a hash.

RemoveKeysWithPrefix(string prefix)

If you prefix the name of a set of keys with the same string, for example "CACHE:", you can easily delete all of these keys at once using this command. It wil look for all keys with the given prefix and delete them all.

object this(string key)

This is a shortcut for SetPermanent(string key, object value) and Get(string key) . For example: Instead of writing: Redis.SetPermanent("mykey", "myvalue"), you can write: Redis("mykey") = "myvalue". In the same way Redis.Get("mykey"), can be written as Redis("mykey").

SetExpiration(string key, int milliseconds)

This will allow you to set the expiration of a key in milliseconds instead of seconds

Common errors

Server object error 'ASP 0177 : 800401f3' 
Server.CreateObject Failed 
/redistest.asp, line 7 
800401f3 

This message occurs when the component isn't registered. Register it using regasm like this:

%SystemRoot%\Microsoft.NET\Framework64\v4.0.30319\regasm [PATH_TO_THE_DLL] /tlb:redis-com-client.tlb /codebase

Server object error 'ASP 0177 : 80070002' 
Server.CreateObject Failed 
/redistest.asp, line 7 
80070002 

You probably registered the component, but forgot the /tlb and /codebase part

StackExchange.Redis.StrongName error '80131500' 
It was not possible to connect to the redis server(s); to create a disconnected multiplexer, disable AbortOnConnectFail. SocketFailure on PING 
/redistest.asp, line 8

You should have a Redis server running on the specified computer. You can run Redis using Windows Subsystem for Linux, by running it on a Linux computer in your network or by finding the Windows Native Redis server online and running it on a Windows computer.

RegAsm : warning RA0000 : Registering an unsigned assembly with /codebase can cause your assembly to interfere with other applications that may be installed on the same computer. The /codebase switch is intended to be used only with signed assemblies. Please give your assembly a strong name and re-register it.

This error occurs when you register the dll, but it can be safely ignored unless you have more applications installed that use the redis-com-client, but in a different version.

License

Licensed under the EUPL - European Union Public License 1.2.

EUPL-1.2 Copyright (c) 2019 Erik Oosterwaal

This wrapper uses the StackExchange.Redis general purpose Redis client, which is licensed under the MIT License (MIT). More information can be found here: /~https://github.com/StackExchange/StackExchange.Redis/blob/master/LICENSE