resolve commands and subcommands

Author: nkaradzhov

packages/client/lib/client/parser.ts

@@ -1,11 +1,13 @@
 import { RedisArgument } from '../RESP/types';
 import { RedisVariadicArgument } from '../commands/generic-transformers';
 
+export type CommandIdentifier = { command: string, subcommand: string };
 export interface CommandParser {
   redisArgs: ReadonlyArray<RedisArgument>;
   keys: ReadonlyArray<RedisArgument>;
   firstKey: RedisArgument | undefined;
   preserve: unknown;
+  commandIdentifier: CommandIdentifier;
 
   push: (...arg: Array<RedisArgument>) => unknown;
   pushVariadic: (vals: RedisVariadicArgument) => unknown;
@@ -44,12 +46,10 @@ export class BasicCommandParser implements CommandParser {
     return tmp.join('_');
   }
 
-  get commandName(): string | undefined {
-    let cmdName = this.#redisArgs[0];
-    if (cmdName instanceof Buffer) {
-      return cmdName.toString();
-    }
-    return cmdName;
+  get commandIdentifier(): CommandIdentifier {
+    const command = this.#redisArgs[0] instanceof Buffer ? this.#redisArgs[0].toString() : this.#redisArgs[0];
+    const subcommand = this.#redisArgs[1] instanceof Buffer ? this.#redisArgs[1].toString() : this.#redisArgs[1];
+    return { command, subcommand };
   }
 
   push(...arg: Array<RedisArgument>) {

packages/client/lib/cluster/request-response-policies/static-policy-resolver.ts

@@ -1,5 +1,6 @@
 import type { PolicyResult, PolicyResolver } from './types';
 import { POLICIES } from './static-policies-data';
+import { CommandIdentifier } from '../../client/parser';
 
 export class StaticPolicyResolver implements PolicyResolver {
   private readonly fallbackResolver: PolicyResolver | null = null;
@@ -21,8 +22,8 @@ export class StaticPolicyResolver implements PolicyResolver {
     return new StaticPolicyResolver(this.policies, fallbackResolver);
   }
 
-  resolvePolicy(command: string): PolicyResult {
-    const parts = command.toLowerCase().split('.');
+  resolvePolicy(commandIdentifier: CommandIdentifier): PolicyResult {
+    const parts = commandIdentifier.command.toLowerCase().split('.');
 
 
     if (parts.length > 2) {
@@ -37,7 +38,7 @@ export class StaticPolicyResolver implements PolicyResolver {
 
     if (!this.policies[moduleName]) {
       if (this.fallbackResolver) {
-        return this.fallbackResolver.resolvePolicy(commandName);
+        return this.fallbackResolver.resolvePolicy(commandIdentifier);
       }
 
       // For std module commands, return 'unknown-command' instead of 'unknown-module'
@@ -51,14 +52,26 @@ export class StaticPolicyResolver implements PolicyResolver {
     if (!this.policies[moduleName][commandName]) {
       // Try fallback resolver if available
       if (this.fallbackResolver) {
-        return this.fallbackResolver.resolvePolicy(commandName);
+        return this.fallbackResolver.resolvePolicy(commandIdentifier);
       }
       return { ok: false, error: 'unknown-command' };
     }
 
+    const policy = this.policies[moduleName][commandName];
+
+    if(policy.subcommands) {
+      const subcommandPolicy = policy.subcommands[commandIdentifier.subcommand];
+      if(subcommandPolicy) {
+        return {
+          ok: true,
+          value: subcommandPolicy
+        }
+      }
+    }
+
     return {
       ok: true,
-      value: this.policies[moduleName][commandName]
+      value: policy
     }
   }
 }

packages/client/lib/cluster/request-response-policies/types.ts

@@ -1,3 +1,4 @@
+import { CommandIdentifier } from '../../client/parser';
 import type { CommandPolicies } from './policies-constants';
 
 export type Either<TOk, TError> =
@@ -6,11 +7,12 @@ export type Either<TOk, TError> =
 
 export type PolicyResult = Either<CommandPolicies, 'policy-not-found' | 'unknown-command' | 'unknown-module' | 'wrong-command-or-module-name' | 'no-policy-resolved'>;
 
+
 export interface PolicyResolver {
   /**
    * The response of the COMMAND command uses "." to separate the module name from the command name.
    */
-  resolvePolicy(command: string): PolicyResult;
+  resolvePolicy(commandIdentifier: CommandIdentifier): PolicyResult;
 
   /**
    * Sets a fallback resolver to use when policies are not found in this resolver.