test: add regression test for explicit null required param

## Summary
- Add `tlsEnabled` config field to Redis source for enabling TLS on
connections
- Apply TLS config to both cluster and standalone Redis clients
- Add test case for TLS config parsing and update docs

This is needed for cloud-managed Redis services like AWS ElastiCache
(Redis OSS) that require TLS for secure connections.

## Example config (tools.yaml)
```yaml
sources:
  leadsforge-redis:
    kind: redis
    address:
      - ${REDIS_HOST}
    clusterEnabled: true
    tls:
      enabled: true
      insecureSkipVerify: true
```

---------

Co-authored-by: Yuan Teoh <45984206+Yuan325@users.noreply.github.com>

docs/en/resources/sources/redis.md

@@ -4,8 +4,8 @@ linkTitle: "Redis"
 type: docs
 weight: 1
 description: >
-    Redis is a in-memory data structure store.
-    
+  Redis is a in-memory data structure store.
+
 ---
 
 ## About
@@ -44,6 +44,9 @@ password: ${MY_AUTH_STRING} # Omit this field if you don't have a password.
 # database: 0
 # clusterEnabled: false
 # useGCPIAM: false
+# tls:
+#   enabled: false
+#   insecureSkipVerify: false
 ```
 
 {{< notice tip >}}
@@ -61,7 +64,7 @@ Here is an example tools.yaml config with [AUTH][auth] enabled:
 ```yaml
 kind: sources
 name: my-redis-cluster-instance
-type: memorystore-redis
+type: redis
 address:
   - 127.0.0.1:6379
 password: ${MY_AUTH_STRING}
@@ -78,7 +81,7 @@ using IAM authentication:
 ```yaml
 kind: sources
 name: my-redis-cluster-instance
-type: memorystore-redis
+type: redis
 address:
   - 127.0.0.1:6379
 useGCPIAM: true
@@ -89,14 +92,16 @@ clusterEnabled: true
 
 ## Reference
 
-| **field**      | **type** | **required** | **description**                                                                                                                 |
-|----------------|:--------:|:------------:|---------------------------------------------------------------------------------------------------------------------------------|
-| type           |  string  |     true     | Must be "memorystore-redis".                                                                                                    |
-| address        |  string  |     true     | Primary endpoint for the Memorystore Redis instance to connect to.                                                              |
-| username       |  string  |    false     | If you are using a non-default user, specify the user name here. If you are using Memorystore for Redis, leave this field blank |
-| password       |  string  |    false     | If you have [Redis AUTH][auth] enabled, specify the AUTH string here                                                            |
-| database       |   int    |    false     | The Redis database to connect to. Not applicable for cluster enabled instances. The default database is `0`.                    |
-| clusterEnabled |   bool   |    false     | Set it to `true` if using a Redis Cluster instance. Defaults to `false`.                                                        |
-| useGCPIAM      |  string  |    false     | Set it to `true` if you are using GCP's IAM authentication. Defaults to `false`.                                                |
+| **field**              | **type** | **required** | **description**                                                                                                                               |
+|------------------------|:--------:|:------------:|-----------------------------------------------------------------------------------------------------------------------------------------------|
+| type                   |  string  |     true     | Must be "redis".                                                                                                                              |
+| address                |  string  |     true     | Primary endpoint for the Memorystore Redis instance to connect to.                                                                            |
+| username               |  string  |    false     | If you are using a non-default user, specify the user name here. If you are using Memorystore for Redis, leave this field blank               |
+| password               |  string  |    false     | If you have [Redis AUTH][auth] enabled, specify the AUTH string here                                                                          |
+| database               |   int    |    false     | The Redis database to connect to. Not applicable for cluster enabled instances. The default database is `0`.                                  |
+| tls.enabled            |   bool   |    false     | Set it to `true` to enable TLS for the Redis connection. Defaults to `false`.                                                                 |
+| tls.insecureSkipVerify |   bool   |    false     | Set it to `true` to skip TLS certificate verification. **Warning:** This is insecure and not recommended for production. Defaults to `false`. |
+| clusterEnabled         |   bool   |    false     | Set it to `true` if using a Redis Cluster instance. Defaults to `false`.                                                                      |
+| useGCPIAM              |   bool   |    false     | Set it to `true` if you are using GCP's IAM authentication. Defaults to `false`.                                                              |
 
 [auth]: https://cloud.google.com/memorystore/docs/redis/about-redis-auth

internal/sources/redis/redis.go

@@ -15,6 +15,7 @@ package redis
 
 import (
 	"context"
+	"crypto/tls"
 	"fmt"
 	"time"
 
@@ -44,14 +45,20 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 }
 
 type Config struct {
-	Name           string   `yaml:"name" validate:"required"`
-	Type           string   `yaml:"type" validate:"required"`
-	Address        []string `yaml:"address" validate:"required"`
-	Username       string   `yaml:"username"`
-	Password       string   `yaml:"password"`
-	Database       int      `yaml:"database"`
-	UseGCPIAM      bool     `yaml:"useGCPIAM"`
-	ClusterEnabled bool     `yaml:"clusterEnabled"`
+	Name           string    `yaml:"name" validate:"required"`
+	Type           string    `yaml:"type" validate:"required"`
+	Address        []string  `yaml:"address" validate:"required"`
+	Username       string    `yaml:"username"`
+	Password       string    `yaml:"password"`
+	Database       int       `yaml:"database"`
+	UseGCPIAM      bool      `yaml:"useGCPIAM"`
+	ClusterEnabled bool      `yaml:"clusterEnabled"`
+	TLS            TLSConfig `yaml:"tls"`
+}
+
+type TLSConfig struct {
+	Enabled            bool `yaml:"enabled"`
+	InsecureSkipVerify bool `yaml:"insecureSkipVerify"`
 }
 
 func (r Config) SourceConfigType() string {
@@ -91,6 +98,13 @@ func initRedisClient(ctx context.Context, r Config) (RedisClient, error) {
 		}
 	}
 
+	var tlsConfig *tls.Config
+	if r.TLS.Enabled {
+		tlsConfig = &tls.Config{
+			InsecureSkipVerify: r.TLS.InsecureSkipVerify,
+		}
+	}
+
 	var client RedisClient
 	var err error
 	if r.ClusterEnabled {
@@ -104,6 +118,7 @@ func initRedisClient(ctx context.Context, r Config) (RedisClient, error) {
 			CredentialsProviderContext: authFn,
 			Username:                   r.Username,
 			Password:                   r.Password,
+			TLSConfig:                  tlsConfig,
 		})
 		err = clusterClient.ForEachShard(ctx, func(ctx context.Context, shard *redis.Client) error {
 			return shard.Ping(ctx).Err()
@@ -125,6 +140,7 @@ func initRedisClient(ctx context.Context, r Config) (RedisClient, error) {
 		CredentialsProviderContext: authFn,
 		Username:                   r.Username,
 		Password:                   r.Password,
+		TLSConfig:                  tlsConfig,
 	})
 	_, err = standaloneClient.Ping(ctx).Result()
 	if err != nil {

internal/sources/redis/redis_test.go

@@ -63,6 +63,9 @@ func TestParseFromYamlRedis(t *testing.T) {
 			database: 1
 			useGCPIAM: true
 			clusterEnabled: true
+			tls:
+			  enabled: true
+			  insecureSkipVerify: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-redis-instance": redis.Config{
@@ -73,6 +76,10 @@ func TestParseFromYamlRedis(t *testing.T) {
 					Database:       1,
 					ClusterEnabled: true,
 					UseGCPIAM:      true,
+					TLS: redis.TLSConfig{
+						Enabled:            true,
+						InsecureSkipVerify: true,
+					},
 				},
 			},
 		},

internal/util/parameters/parameters.go

@@ -144,7 +144,7 @@ func ParseParams(ps Parameters, data map[string]any, claimsMap map[string]map[st
 			// parse non auth-required parameter
 			var ok bool
 			v, ok = data[name]
-			if !ok {
+			if !ok || v == nil {
 				v = p.GetDefault()
 				// if the parameter is required and no value given, throw an error
 				if CheckParamRequired(p.GetRequired(), v) {

internal/util/parameters/parameters_test.go

@@ -2347,3 +2347,23 @@ func TestCheckParamRequired(t *testing.T) {
 		})
 	}
 }
+
+func TestParseParams_ExplicitNullForRequiredParam(t *testing.T) {
+	// Define a required string parameter
+	params := parameters.Parameters{
+		parameters.NewStringParameter("required_param", "this is required"),
+	}
+
+	// Input map with explicit nil
+	input := map[string]any{
+		"required_param": nil,
+	}
+
+	// Call ParseParams
+	_, err := parameters.ParseParams(params, input, nil)
+
+	// Expect an error because the parameter is required
+	if err == nil {
+		t.Errorf("ParseParams allowed explicit nil for required parameter, expected error")
+	}
+}