Chapter 64. Spring Redis
The producer and consumer are supported.
This component allows sending and receiving messages from Redis. Redis is an advanced key-value store where keys can contain strings, hashes, lists, sets and sorted sets. In addition Redis provides pub/sub functionality for inter-app communications. Camel provides a producer for executing commands, a consumer for subscribing to pub/sub messages, and an idempotent repository for filtering out duplicate messages.
Prerequisites
To use this component, you must have a Redis server running.
64.1. URI Format
spring-redis://host:port[?options]
64.2. Configuring Options
Camel components are configured on two separate levels:
- component level
- endpoint level
64.2.1. Configuring Component Options
The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example, a component may have security settings, credentials for authentication, URLs for network connection.
Some components only have a few options, and others may have many. Because components typically have pre-configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.
Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.
64.2.2. Configuring Endpoint Options
Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as a consumer (from) or as a producer (to), or used for both.
Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL and DataFormat DSL as a type safe way of configuring endpoints and data formats in Java.
A good practice when configuring options is to use Property Placeholders, which allows you to not hardcode URLs, port numbers, sensitive information, and other settings. In other words, placeholders allow you to externalize the configuration from your code, and gives more flexibility and reuse.
The following two sections lists all the options, firstly for the component followed by the endpoint.
64.3. Component Options
The Spring Redis component supports 4 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
redisTemplate (common) | Autowired Reference to a pre-configured RedisTemplate instance to use. | RedisTemplate | |
bridgeErrorHandler (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer uses the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean |
lazyStartProducer (producer) | Whether the producer should be started lazy (on the first message). By starting lazy, you can use this to allow CamelContext and routes to start up in situations where a producer may otherwise fail during starting and cause the route to fail being started. By starting lazy, Camel’s routing error handlers handle any startup failures while routing messages. Beware that when the first message is processed, creating, and starting, the producer may take a little time and prolong the total processing time of the processing. | false | boolean |
autowiredEnabled (advanced) | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring of JDBC data sources, JMS connection factories, and AWS Clients. | true | boolean |
64.4. Endpoint Options
The Spring Redis endpoint is configured using URI syntax:
spring-redis:host:port
with the following path and query parameters:
64.4.1. Path Parameters (2 parameters)
Name | Description | Default | Type |
---|---|---|---|
host (common) | Required The host where the Redis server is running. | String | |
port (common) | Required Redis server port number. | Integer |
64.4.2. Query Parameters (10 parameters)
Name | Description | Default | Type |
---|---|---|---|
channels (common) | List of topic names or name patterns to subscribe to. Multiple names can be separated by a comma. | String | |
command (common) | Default command, which can be overridden by message header. Notice that the consumer only supports the following commands only: PSUBSCRIBE and SUBSCRIBE. Enum values:
| SET | Command |
connectionFactory (common) | Reference to a pre-configured RedisConnectionFactory instance to use. | RedisConnectionFactory | |
redisTemplate (common) | Reference to a pre-configured RedisTemplate instance to use. | RedisTemplate | |
serializer (common) | Reference to a pre-configured RedisSerializer instance to use. | RedisSerializer | |
bridgeErrorHandler (consumer (advanced)) | Allows for bridging the consumer to the Camel routing Error Handler, which means any exceptions that occurred while the consumer is trying to pick up incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. The consumer defaults to use the org.apache.camel.spi.ExceptionHandler to deal with exceptions. These exceptions log at WARN or ERROR level and ignored. | False | Boolean |
exceptionHandler (consumer (advanced)) | To let the consumer use a custom ExceptionHandler. If you enable the bridgeErrorHandler option, this option is not used. By default, the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. | ExceptionHandler | |
exchangePattern (consumer (advanced)) | Sets the exchange pattern when the consumer creates an exchange. Enum values:
| ExchangePattern | |
listenerContainer (consumer (advanced)) | Reference to a pre-configured RedisMessageListenerContainer instance to use. | RedisMessageListenerContainer | |
lazyStartProducer (Producer (advanced)) | Whether the producer should be started lazy (on the first message). By starting lazy, you can use this to allow CamelContext and routes to start up in situations where a producer may otherwise fail during starting and cause the route startup to fail. By deferring this startup to be lazy, the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | False | Boolean |
64.5. Message Headers
The Spring Redis component supports 29 message header(s), which is/are listed below:
Name | Description | Default | Type |
---|---|---|---|
CamelRedis.Command (producer) Constant: COMMAND | The command to perform. | String | |
CamelRedis.Key (common) Constant: KEY | The key. | String | |
CamelRedis.Keys (common) Constant: KEYS | The keys. | Collection | |
CamelRedis.Field (common) Constant: FIELD | The field. | String | |
CamelRedis.Fields (common) Constant: FIELDS | The fields. | Collection | |
CamelRedis.Value (common) Constant: VALUE | The value. | Object | |
CamelRedis.Values (common) Constant: VALUES | The values. | Map | |
CamelRedis.Start (common) Constant: START | Start. | Long | |
CamelRedis.End (common) Constant: END | End. | Long | |
CamelRedis.Timeout (common) Constant: TIMEOUT | The timeout. | Long | |
CamelRedis.Offset (common) Constant: OFFSET | The offset. | Long | |
CamelRedis.Destination (common) Constant: DESTINATION | The destination. | String | |
CamelRedis.Channel (common) Constant: CHANNEL | The channel. | byte[] or String | |
CamelRedis.Message (common) Constant: MESSAGE | The message. | Object | |
CamelRedis.Index (common) Constant: INDEX | The index. | Long | |
CamelRedis.Position (common) Constant: POSITION | The position. | String | |
CamelRedis.Pivot (common) Constant: PIVOT | The pivot. | String | |
CamelRedis.Count (common) Constant: COUNT | Count. | Long | |
CamelRedis.Timestamp (common) Constant: TIMESTAMP | The timestamp. | Long | |
CamelRedis.Pattern (common) Constant: PATTERN | The pattern. | byte[] or String | |
CamelRedis.Db (common) Constant: DB | The db. | Integer | |
CamelRedis.Score (common) Constant: SCORE | The score. | Double | |
CamelRedis.Min (common) Constant: MIN | The min. | Double | |
CamelRedis.Max (common) Constant: MAX | The max. | Double | |
CamelRedis.Increment (common) Constant: INCREMENT | Increment. | Double | |
CamelRedis.WithScore (common) Constant: WITHSCORE | WithScore. | Boolean | |
CamelRedis.Latitude (common) Constant: LATITUDE | Latitude. | Double | |
CamelRedis.Longitude (common) Constant: LONGITUDE | Latitude. | Double | |
CamelRedis.Radius (common) Constant: RADIUS | Radius. | Double |
64.6. Usage
Also, see the available unit tests.
Redis Producer
from(“direct:start”) .setHeader("CamelRedis.Key", constant(key)) .setHeader("CamelRedis.Value", constant(value)) .to("spring-redis://host:port?command=SET&redisTemplate=#redisTemplate");
Redis Consumer
from("spring-redis://host:port?command=SUBSCRIBE&channels=myChannel") .log("Received message: ${body}");
Where '//host:port' is URL address for running Redis server.
64.6.1. Message headers evaluated by the Redis producer
The producer issues commands to the server and each command has a different set of parameters with specific types. The result from the command execution is returned in the message body.
Hash Commands | Description | Parameters | Result |
---|---|---|---|
| Set the string value of a hash field |
| Void |
| Get the value of a hash field |
| String |
| Set the value of a hash field, only if the field does not exist |
| Void |
| Set multiple hash fields to multiple values |
| Void |
| Get the values of all the given hash fields |
| Collection<Object> |
| Increment the integer value of a hash field by the given number |
| Long |
| Determine if a hash field exists |
| Boolean |
| Delete one or more hash fields |
| Void |
| Get the number of fields in a hash |
| Long |
| Get all the fields in a hash |
| Set<String> |
| Get all the values in a hash |
| Collection<Object> |
| Get all the fields and values in a hash |
| Map<String, Object> |
List Commands | Description | Parameters | Result |
---|---|---|---|
RPUSH | Append one or multiple values to a list |
| Long |
RPUSHX | Append a value to a list, only if the list exists |
| Long |
LPUSH | Prepend one or multiple values to a list |
| Long |
LLEN | Get the length of a list |
| Long |
LRANGE | Get a range of elements from a list |
| List<Object> |
LTRIM | Trim a list to the specified range |
| Void |
LINDEX | Get an element from a list by its index |
| String |
LINSERT | Insert an element before or after another element in a list |
| Long |
LSET | Set the value of an element in a list by its index |
| Void |
LREM | Remove elements from a list |
| Long |
LPOP | Remove and get the first element in a list |
| Object |
RPOP | Remove and get the last element in a list |
| String |
RPOPLPUSH | Remove the last element in a list, append it to another list and return it |
| Object |
BRPOPLPUSH | Pop a value from a list, push it to another list and return it; or block until one is available |
| Object |
BLPOP | Remove and get the first element in a list, or block until one is available |
| Object |
BRPOP | Remove and get the last element in a list, or block until one is available |
| String |
Set Commands | Description | Parameters | Result |
---|---|---|---|
SADD | Add one or more members to a set |
| Boolean |
SMEMBERS | Get all the members in a set |
| Set<Object> |
SREM | Remove one or more members from a set |
| Boolean |
SPOP | Remove and return a random member from a set |
| String |
SMOVE | Move a member from one set to another |
| Boolean |
SCARD | Get the number of members in a set |
| Long |
SISMEMBER | Determine if a given value is a member of a set |
| Boolean |
SINTER | Intersect multiple sets |
| Set<Object> |
SINTERSTORE | Intersect multiple sets and store the resulting set in a key |
| Void |
SUNION | Add multiple sets |
| Set<Object> |
SUNIONSTORE | Add multiple sets and store the resulting set in a key |
| Void |
SDIFF | Subtract multiple sets |
| Set<Object> |
SDIFFSTORE | Subtract multiple sets and store the resulting set in a key |
| Void |
SRANDMEMBER | Get one or multiple random members from a set |
| String |
Ordered set Commands | Description | Parameters | Result |
---|---|---|---|
ZADD | Add one or more members to a sorted set, or update its score if it already exists |
| Boolean |
ZRANGE | Return a range of members in a sorted set, by index |
| Object |
ZREM | Remove one or more members from a sorted set |
| Boolean |
ZINCRBY | Increment the score of a member in a sorted set |
| Double |
ZRANK | Determine the index of a member in a sorted set |
| Long |
ZREVRANK | Determine the index of a member in a sorted set, with scores ordered from high to low |
| Long |
ZREVRANGE | Return a range of members in a sorted set, by index, with scores ordered from high to low |
| Object |
ZCARD | Get the number of members in a sorted set |
| Long |
ZCOUNT | Count the members in a sorted set with scores within the given values |
| Long |
ZRANGEBYSCORE | Return a range of members in a sorted set, by score |
| Set<Object> |
ZREVRANGEBYSCORE | Return a range of members in a sorted set, by score, with scores ordered from high to low |
| Set<Object> |
ZREMRANGEBYRANK | Remove all members in a sorted set within the given indexes |
| Void |
ZREMRANGEBYSCORE | Remove all members in a sorted set within the given scores |
| Void |
ZUNIONSTORE | Add multiple sorted sets and store the resulting sorted set in a new key |
| Void |
ZINTERSTORE | Intersect multiple sorted sets and store the resulting sorted set in a new key |
| Void |
String Commands | Description | Parameters | Result |
---|---|---|---|
SET | Set the string value of a key |
| Void |
GET | Get the value of a key |
| Object |
STRLEN | Get the length of the value stored in a key |
| Long |
APPEND | Append a value to a key |
| Integer |
SETBIT | Sets or clears the bit at offset in the string value stored at key |
| Void |
GETBIT | Returns the bit value at offset in the string value stored at key |
| Boolean |
SETRANGE | Overwrite part of a string at key starting at the specified offset |
| Void |
GETRANGE | Get a substring of the string stored at a key |
| String |
SETNX | Set the value of a key, only if the key does not exist |
| Boolean |
SETEX | Set the value and expiration of a key |
| Void |
DECRBY | Decrement the integer value of a key by the given number |
| Long |
DECR | Decrement the integer value of a key by one |
| Long |
INCRBY | Increment the integer value of a key by the given amount |
| Long |
INCR | Increment the integer value of a key by one |
| Long |
MGET | Get the values of all the given keys |
| List<Object> |
MSET | Set multiple keys to multiple values |
| Void |
MSETNX | Set multiple keys to multiple values, only if none of the keys exist |
| Void |
GETSET | Set the string value of a key and return its old value |
| Object |
Key Commands | Description | Parameters | Result |
---|---|---|---|
EXISTS | Determine if a key exists |
| Boolean |
DEL | Delete a key |
| Void |
TYPE | Determine the type stored at key |
| DataType |
KEYS | Find all keys matching the given pattern |
| Collection<String> |
RANDOMKEY | Return a random key from the keyspace |
| String |
RENAME | Rename a key |
| Void |
RENAMENX | Rename a key, only if the new key does not exist |
| Boolean |
EXPIRE | Set a key’s time to live in seconds |
| Boolean |
SORT | Sort the elements in a list, set or sorted set |
| List<Object> |
PERSIST | Remove the expiration from a key |
| Boolean |
EXPIREAT | Set the expiration for a key as a UNIX timestamp |
| Boolean |
PEXPIRE | Set a key’s time to live in milliseconds |
| Boolean |
PEXPIREAT | Set the expiration for a key as a UNIX timestamp specified in milliseconds |
| Boolean |
TTL | Get the time to live for a key |
| Long |
MOVE | Move a key to another database |
| Boolean |
Geo Commands | Description | Parameters | Result |
---|---|---|---|
GEOADD | Adds the specified geospatial items (latitude, longitude, name) to the specified key |
| Long |
GEODIST | Return the distance between two members in the geospatial index for the specified key |
| Distance |
GEOHASH | Return valid Geohash strings representing the position of an element in the geospatial index for the specified key |
| List<String> |
GEOPOS | Return the positions (longitude, latitude) of an element in the geospatial index for the specified key |
| List<Point> |
GEORADIUS | Return the element in the geospatial index for the specified key, which is within the borders of the area specified with the central location and the maximum distance from the center (the radius) |
| GeoResults |
GEORADIUSBYMEMBER | This command is exactly like GEORADIUS with the sole difference that instead of taking, as the center of the area to query, a longitude and latitude value, it takes the name of a member already existing inside the geospatial index for the specified key |
| GeoResults |
Other Commands | Description | Parameters | Result |
---|---|---|---|
MULTI | Mark the start of a transaction block | none | Void |
DISCARD | Discard all commands issued after MULTI | none | Void |
EXEC | Execute all commands issued after MULTI | none | Void |
WATCH | Watch the given keys to determine the execution of the MULTI/EXEC block |
| Void |
UNWATCH | Forget about all watched keys | none | Void |
ECHO | Echo the given string |
| String |
PING | Ping the server | none | String |
QUIT | Close the connection | none | Void |
PUBLISH | Post a message to a channel |
| Void |
64.7. Dependencies
Maven users will need to add the following dependency to their pom.xml.
pom.xml
<dependency> <groupId>org.apache.camel.springboot</groupId> <artifactId>camel-spring-redis-starter</artifactId> </dependency>
Use the BOM to get the version.
<dependencyManagement> <dependencies> <dependency> <groupId>com.redhat.camel.springboot.platform</groupId> <artifactId>camel-spring-boot-bom</artifactId> <version>${camel-spring-boot-version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement>
64.8. Spring Boot Auto-Configuration
When using spring-redis with Spring Boot, ensure you use the following Maven dependency to have support for auto-configuration:
<dependency> <groupId>org.apache.camel.springboot</groupId> <artifactId>camel-spring-redis-starter</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency>
The component supports 5 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
camel.component.spring-redis.autowired-enabled | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatically configure JDBC data sources, JMS connection factories, AWS Clients, etc. | True | Boolean |
camel.component.spring-redis.bridge-error-handler | Allows for bridging the consumer to the Camel routing Error Handler, which means any exceptions that occur while the consumer is trying to pick up incoming messages, or the likes, will be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | False | Boolean |
camel.component.spring-redis.enabled | Whether to enable auto configuration of the spring-redis component. This is enabled by default. | Boolean | |
camel.component.spring-redis.lazy-start-producer | Whether the producer should be started lazy (on the first message). By starting lazy, you can allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail start up. By deferring this startup to be lazy, the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | False | Boolean |
camel.component.spring-redis.redis-template | Reference to a pre-configured RedisTemplate instance to use. The option is an org.springframework.data.redis.core.RedisTemplate type. | RedisTemplate |