Add TemplateRedisFilters

Author: mythz

src/ServiceStack.Redis/TemplateRedisFilters.cs

@@ -0,0 +1,166 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+using ServiceStack.Configuration;
+using ServiceStack.Templates;
+
+namespace ServiceStack.Redis
+{
+    public class RedisSearchCursorResult
+    {
+        public int Cursor { get; set; }
+        public List<RedisSearchResult> Results { get; set; }
+    }
+
+    public class RedisSearchResult
+    {
+        public string Id { get; set; }
+        public string Type { get; set; }
+        public long Ttl { get; set; }
+        public long Size { get; set; }
+    }
+
+    public class TemplateRedisFilters : TemplateFilter
+    {
+        public IRedisClientsManager RedisManager { get; set; }
+        public IAppSettings AppSettings { get; set; }
+        T exec<T>(Func<IRedisClient, T> fn)
+        {
+            using (var db = RedisManager.GetClient())
+            {
+                return fn(db);
+            }
+        }
+
+        static Dictionary<string, int> cmdArgCounts = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase) {
+            { "SET", 3 }
+        };
+
+        List<string> parseCommandString(string cmd)
+        {
+            var args = new List<string>();
+            var lastPos = 0;
+            for (var i = 0; i < cmd.Length; i++)
+            {
+                var c = cmd[i];
+                if (c == '{' || c == '[')
+                {
+                    break; //stop splitting args if value is complex type
+                }
+                if (c == ' ')
+                {
+                    var arg = cmd.Substring(lastPos, i - lastPos);
+                    args.Add(arg);
+                    lastPos = i + 1;
+
+                    //if we've reached the command args count, capture the rest of the body as the last arg
+                    if (cmdArgCounts.TryGetValue(args[0], out int argCount) && args.Count == argCount - 1)
+                        break;
+                }
+            }
+            args.Add(cmd.Substring(lastPos));
+            return args;
+        }
+
+        object toObject(RedisText r)
+        {
+            if (r == null)
+                return null;
+
+            if (r.Children != null && r.Children.Count > 0)
+            {
+                var to = new List<object>();
+                for (var i = 0; i < r.Children.Count; i++)
+                {
+                    var child = r.Children[i];
+                    var value = child.Text ?? toObject(child);
+                    to.Add(value);
+                }
+                return to;
+            }
+            return r.Text;
+        }
+
+        public object redisCall(string cmd)
+        {
+            if (string.IsNullOrEmpty(cmd))
+                return null;
+
+            var args = parseCommandString(cmd);
+            var objParams = args.Select(x => (object)x).ToArray();
+            var redisText = exec(r => r.Custom(objParams));
+            var result = toObject(redisText);
+            return result;
+        }
+
+        public List<RedisSearchResult> redisSearchKeys(TemplateScopeContext scope, string query) => redisSearchKeys(scope, query, null);
+        public List<RedisSearchResult> redisSearchKeys(TemplateScopeContext scope, string query, object options)
+        {
+            var json = redisSearchKeysAsJson(scope, query, options);
+            const string noResult = "{\"cursor\":0,\"results\":{}}";
+            if (json == noResult)
+                return new List<RedisSearchResult>();
+
+            var searchResults = json.FromJson<RedisSearchCursorResult>();
+            return searchResults.Results;
+        }
+
+        public string redisSearchKeysAsJson(TemplateScopeContext scope, string query, object options)
+        {
+            if (string.IsNullOrEmpty(query))
+                return null;
+
+            var args = scope.AssertOptions(nameof(redisSearchKeys), options);
+            var limit = args.TryGetValue("limit", out object value)
+                ? value.ConvertTo<int>()
+                : scope.GetValue("redis.search.limit") ?? 100;
+
+            const string LuaScript = @"
+local limit = tonumber(ARGV[2])
+local pattern = ARGV[1]
+local cursor = tonumber(ARGV[3])
+local len = 0
+local keys = {}
+repeat
+    local r = redis.call('scan', cursor, 'MATCH', pattern, 'COUNT', limit)
+    cursor = tonumber(r[1])
+    for k,v in ipairs(r[2]) do
+        table.insert(keys, v)
+        len = len + 1
+        if len == limit then break end
+    end
+until cursor == 0 or len == limit
+local cursorAttrs = {['cursor'] = cursor, ['results'] = {}}
+if len == 0 then
+    return cjson.encode(cursorAttrs)
+end
+
+local keyAttrs = {}
+for i,key in ipairs(keys) do
+    local type = redis.call('type', key)['ok']
+    local pttl = redis.call('pttl', key)
+    local size = 0
+    if type == 'string' then
+        size = redis.call('strlen', key)
+    elseif type == 'list' then
+        size = redis.call('llen', key)
+    elseif type == 'set' then
+        size = redis.call('scard', key)
+    elseif type == 'zset' then
+        size = redis.call('zcard', key)
+    elseif type == 'hash' then
+        size = redis.call('hlen', key)
+    end
+    local attrs = {['id'] = key, ['type'] = type, ['ttl'] = pttl, ['size'] = size, ['foo'] = 'bar'}
+    table.insert(keyAttrs, attrs)    
+end
+cursorAttrs['results'] = keyAttrs
+return cjson.encode(cursorAttrs)";
+
+            var json = exec(r => r.ExecCachedLua(LuaScript, sha1 =>
+                r.ExecLuaShaAsString(sha1, query, limit.ToString(), "0")));
+
+            return json;
+        }
+    }
+}