Redis 中文文档


Advanced in-memory caching module for JavaScript.


For when you need caching but running Redis would be an overkill.


KV.JS is a fast, in-memory data store written in pure JavaScript, heavily inspired by Redis and Memcached. It is capable of handling multiple data types, including strings, lists, sets, sorted sets, hashes, and geospatial indexes. Additionally, with more than 140 functions, KV.JS supports a vast variety of operations, ranging from SET, GET, EXPIRE, DEL to INCR, DECR, LPUSH, RPUSH, SADD, SREM, HSET, HGET, and many many more.

Installation


  1. ``` shell
  2. npm install @heyputer/kv.js
  3. ```

Usage


  1. ``` js
  2. const kvjs = require('@heyputer/kv.js');

  4. // Create a new kv.js instance
  5. const kv = new kvjs();

  7. // Set a key
  8. kv.set('foo', 'bar');

  10. // Get the key's value
  11. kv.get('foo'); // "bar"

  13. // Delete the key
  14. kv.del('foo');

  16. // Set another key
  17. kv.set('username', 'heyputer');

  19. // Automatically delete the key after 60 seconds
  20. kv.expire('username', 60);
  21. ```

More usage examples


decr
  1. ``` js
  2. // Assuming the key 'counter' has been set, decrement the value of the key by 1
  3. kv.decr('counter');
  4. ```

decrby
  1. ``` js
  2. // Assuming the key 'counter' has been set, decrement the value of the key by 5 (output: -5)
  3. kv.decrby('counter', 5);

  5. // Assuming the key 'counter' has been set, decrement the value of the key by -3 (output: 3)
  6. kv.decrby('counter', -3);

  8. // Assuming the key 'counter' has been set, decrement the value of the key by 10 (output: -7)
  9. kv.decrby('counter', 10);

  11. // Assuming the key 'counter' has been set, decrement the value of the key by 0 (output: 0)
  12. kv.decrby('counter', 0);

  14. // Assuming the key 'counter' has been set, decrement the value of the key by -7 (output: 4)
  15. kv.decrby('counter', -7);
  16. ```

del Delete specified key(s). If a key does not exist, it is ignored.

  1. ``` js
  2. // Delete a single key ("key1"), returns 1 if the key was deleted, 0 if it did not exist or has expired.
  3. kv.del("key1");

  5. // Delete multiple keys ("key2" and "key3"), returns the number of keys deleted (0, 1, or 2) depending on which keys existed and were not expired.
  6. kv.del("key2", "key3");

  8. // Attempt to delete a non-existent key ("nonExistentKey"), returns 0 since the key does not exist.
  9. kv.del("nonExistentKey");

  11. // Attempt to delete an expired key ("expiredKey"), returns 0 if the key has expired.
  12. kv.del("expiredKey");

  14. // Delete multiple keys ("key4", "key5", "key6"), returns the number of keys deleted (0 to 3) depending on which keys existed and were not expired.
  15. kv.del("key4", "key5", "key6");
  16. ```

exists Check if one or more keys exist.

  1. ``` js
  2. // Check if a single key ("key1") exists, returns 1 if the key exists and is not expired, 0 otherwise.
  3. kv.exists("key1");

  5. // Check if multiple keys ("key2" and "key3") exist, returns the number of existing keys (0, 1, or 2) that are not expired.
  6. kv.exists("key2", "key3");

  8. // Check if a non-existent key ("nonExistentKey") exists, returns 0 since the key does not exist.
  9. kv.exists("nonExistentKey");

  11. // Check if an expired key ("expiredKey") exists, returns 0 if the key has expired.
  12. kv.exists("expiredKey");

  14. // Check if multiple keys ("key4", "key5", "key6") exist, returns the number of existing keys (0 to 3) that are not expired.
  15. kv.exists("key4", "key5", "key6");
  16. ```

expire
  1. ``` js
  2. // Set a key's time to live in seconds without any option
  3. kv.expire('username', 60);

  5. // Set a key's time to live in seconds only if the key does not have an expiry time
  6. kv.expire('username', 120, {NX: true});

  8. // Set a key's time to live in seconds only if the key already has an expiry time
  9. kv.expire('username', 180, {XX: true});

  11. // Set a key's time to live in seconds only if the key's expiry time is greater than the specified time
  12. kv.expire('username', 240, {GT: true});

  14. // Set a key's time to live in seconds only if the key's expiry time is less than the specified time
  15. kv.expire('username', 300, {LT: true});
  16. ```

expireat
  1. ``` js
  2. // Set the TTL for key "user1" to expire in 30 seconds.
  3. kv.expireat("user1", Math.floor(Date.now() / 1000) + 30);

  5. // Set the TTL for key "user2" to expire at a specific UNIX timestamp (e.g. 1700000000), only if the key does not already have an expiry time.
  6. kv.expireat("user2", 1700000000, {NX: true});

  8. // Set the TTL for key "user3" to expire in 45 seconds, only if the key already has an expiry time.
  9. kv.expireat("user3", Math.floor(Date.now() / 1000) + 45, {XX: true});

  11. // Set the TTL for key "user4" to expire in 60 seconds, only if the new TTL is greater than the current TTL.
  12. kv.expireat("user4", Math.floor(Date.now() / 1000) + 60, {GT: true});

  14. // Set the TTL for key "user5" to expire in 15 seconds, only if the new TTL is less than the current TTL.
  15. kv.expireat("user5", Math.floor(Date.now() / 1000) + 15, {LT: true});

  17. // Set the TTL for key "user6" to expire at a specific UNIX timestamp (e.g. 1705000000), only if the key already have an expiry time.
  18. kv.expireat("user6", 1705000000, {XX: true});

  20. // Set the TTL for key "user7" to expire in 90 seconds, only if the key does not already have an expiry time.
  21. kv.expireat("user7", Math.floor(Date.now() / 1000) + 90, {NX: true});

  23. // Set the TTL for key "user8" to expire at a specific UNIX timestamp (e.g. 1710000000), only if the new TTL is greater than the current TTL.
  24. kv.expireat("user8", 1710000000, {GT: true});

  26. // Set the TTL for key "user9" to expire in 120 seconds, only if the new TTL is less than the current TTL.
  27. kv.expireat("user9", Math.floor(Date.now() / 1000) + 120, {LT: true});

  29. // Set the TTL for key "user10" to expire in 5 seconds.
  30. kv.expireat("user10", Math.floor(Date.now() / 1000) + 5);
  31. ```

get Get the value of a key.

  1. ``` js
  2. // Example 1: Get the value of an existing key
  3. kv.get('username'); // Returns the value associated with the key 'username'

  5. // Example 2: Get the value of a non-existent key
  6. kv.get('nonexistent'); // Returns null

  8. // Example 3: Get the value of an expired key (assuming 'expiredKey' was set with an expiration)
  9. kv.get('expiredKey'); // Returns null

  11. // Example 4: Get the value of a key after updating its value
  12. kv.set('color', 'red'); // Sets the key 'color' to the value 'red'
  13. kv.get('color'); // Returns 'red'

  15. // Example 5: Get the value of a key after deleting it (assuming 'deletedKey' was previously set)
  16. kv.delete('deletedKey'); // Deletes the key 'deletedKey'
  17. kv.get('deletedKey'); // Returns null
  18. ```

getset
  1. ``` js
  2. // Set initial values for key.
  3. kv.set("username", "John");

  5. // Replace the value of "username" with "Alice" and return the old value ("John").
  6. kv.getset("username", "Alice"); // Returns "John"

  8. // Replace the value of "nonExistentKey" with "Bob" and return the old value (null).
  9. kv.getset("nonExistentKey", "Bob"); // Returns null
  10. ```

incr
  1. ``` js
  2. // Increment the value of an existing key ("key1") by 1, returns the new value of the key.
  3. kv.incr("key1");

  5. // Increment the value of a non-existing key ("nonExistentKey"), returns 1 as the new value of the key (since it's initialized as 0 and incremented by 1).
  6. kv.incr("nonExistentKey");

  8. // Increment the value of an expired key ("expiredKey"), if the key has expired, it will be treated as a new key, returns 1 as the new value of the key.
  9. kv.incr("expiredKey");

  11. // Increment the value of an existing key ("key2") with a non-numeric value, throws an error.
  12. kv.incr("key2"); // Assuming "key2" has a non-numeric value

  14. // Increment the value of an existing key ("key3") with a numeric value, returns the incremented value of the key.
  15. kv.incr("key3"); // Assuming "key3" has a numeric value
  16. ```

incrby
  1. ``` js
  2. // Increment the value of a key by 5 (assuming the key does not exist or its value is an integer)
  3. kv.incrby('counter', 5);

  5. // Increment the value of a key by -3 (assuming the key does not exist or its value is an integer)
  6. kv.incrby('counter', -3);

  8. // Increment the value of a key by 10 (assuming the key does not exist or its value is an integer)
  9. kv.incrby('counter', 10);

  11. // Increment the value of a key by 0 (assuming the key does not exist or its value is an integer)
  12. kv.incrby('counter', 0);

  14. // Increment the value of a key by -7 (assuming the key does not exist or its value is an integer)
  15. kv.incrby('counter', -7);
  16. ```

keys
  1. ``` js
  2. // Find all keys matching the pattern 'user:*' (assuming some keys matching the pattern exist)
  3. kv.keys('user:*');

  5. // Find all keys matching the pattern 'product:*' (assuming some keys matching the pattern exist)
  6. kv.keys('product:*');

  8. // Find all keys matching the pattern '*:email' (assuming some keys matching the pattern exist)
  9. kv.keys('*:email');

  11. // Find all keys matching the pattern 'username' (assuming some keys matching the pattern exist)
  12. kv.keys('username');
  13. ```

mget
  1. ``` js
  2. // Retrieve the values of key 'username'
  3. kv.mget('username');

  5. // Retrieve the values of keys 'username' and 'email' (assuming they exist)
  6. kv.mget('username', 'email');
  7. ```

mset
  1. ``` js
  2. // Set the values of keys 'username' and 'email' to 'johndoe' and 'johndoe@example.com', respectively
  3. kv.mset('username', 'johndoe', 'email', 'johndoe@example.com');

  5. // Set the values of keys 'counter' and 'score' to 0 and 100, respectively
  6. kv.mset('counter', 0, 'score', 100);
  7. ```

persist
  1. ``` js
  2. // Remove the expiration from the key "key1".
  3. kv.persist("key1");
  4. ```

rename
  1. ``` js
  2. // Rename the key 'username' to 'email' (assuming 'username' exists)
  3. kv.rename('username', 'email');
  4. ```

sadd Add one or more members to a set stored at key.

  1. ``` js
  2. // add a member to a set
  3. kv.sadd('set1', 'member1'); // Output: true

  5. // add multiple members to a set
  6. kv.sadd('set1', 'member2', 'member3'); // Output: true

  8. // print the members of a set
  9. kv.smembers('set1'); // Output: ['member1', 'member2', 'member3']

  11. // add a member to a set that already contains the member
  12. kv.sadd('set1', 'member1'); // Output: false

  14. // add a member to a non-existent set
  15. kv.sadd('set2', 'member1'); // Output: true
  16. ```

scard Returns the number of members of the set stored at key.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // print the number of members in a set
  5. kv.scard('set1'); // Output: 3
  6. ```

sdiff This method retrieves the members of a set that are present in the first set but not in any of the subsequent sets, and returns them as a new set.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // add a few members to a second set
  5. kv.sadd('set2', 'member2', 'member3', 'member4'); // Output: true
  6. // print the members of the first set that are not in the second set
  7. kv.sdiff('set1', 'set2'); // Output: ['member1']
  8. ```

set Set the string value of a key with optional NX/XX/GET/EX/PX/EXAT/PXAT/KEEPTTL, GET, and expiration options.

  1. ``` js
  2. // Set a basic key-value pair
  3. kv.set('username', 'john_doe'); // Output: true

  5. // Set a key-value pair only if the key does not already exist (NX option)
  6. kv.set('username', 'jane_doe', {NX: true});

  8. // Set a key-value pair only if the key already exists (XX option)
  9. kv.set('email', 'jane@example.com', {XX: true});

  11. // Set a key-value pair with an expiration time in seconds (EX option)
  12. kv.set('session_token', 'abc123', {EX: 3600});

  14. // Get the existing value and set a new value for a key (GET option)
  15. kv.set('username', 'mary_smith', {GET: true});

  17. // Set a key-value pair with an expiration time in milliseconds (PX option)
  18. kv.set('temp_data', '42', {PX: 1000});

  20. // Set a key-value pair with an expiration time at a specific Unix timestamp in seconds (EXAT option)
  21. kv.set('event_data', 'event1', {EXAT: 1677649420});

  23. // Set a key-value pair with an expiration time at a specific Unix timestamp in milliseconds (PXAT option)
  24. kv.set('event_data2', 'event2', {PXAT: 1677649420000});

  26. // Set a key-value pair and keep the original TTL if the key already exists (KEEPTTL option)
  27. kv.set('username', 'alice_wonder', {KEEPTTL: true});

  29. // Set a key-value pair with multiple options (NX, EX, and GET options)
  30. kv.set('new_user', 'carol_baker', {NX: true, EX: 7200, GET: true});
  31. ```

sinter This method retrieves the members that are present in all the sets provided as arguments, and returns them as a new set representing the intersection of those sets.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // add a few members to a second set
  5. kv.sadd('set2', 'member2', 'member3', 'member4'); // Output: true
  6. // print the members that are present in both sets
  7. kv.sinter('set1', 'set2'); // Output: ['member2', 'member3']
  8. ```

sismember This method determines if a given value is a member of a set.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // check if a member is present in a set
  5. kv.sismember('set1', 'member1'); // Output: true
  6. // check if a member is not present in a set
  7. kv.sismember('set1', 'member4'); // Output: false
  8. ```

smove This method moves a member from one set to another.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // add a few members to a second set
  5. kv.sadd('set2', 'member4', 'member5', 'member6'); // Output: true
  6. // move a member from one set to another
  7. kv.smove('set1', 'set2', 'member1'); // Output: true
  8. // print the members of the first set
  9. kv.smembers('set1'); // Output: ['member2', 'member3']
  10. // print the members of the second set
  11. kv.smembers('set2'); // Output: ['member1', 'member4', 'member5', 'member6']
  12. ```

sort Sort the elements in a list, set or sorted set.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // sort the members of a set
  5. kv.sort('set1'); // Output: ['member1', 'member2', 'member3']

  7. // add a few members to a sorted set
  8. kv.zadd('zset1', 1, 'member1', 2, 'member2', 3, 'member3'); // Output: true
  9. // sort the members of a sorted set
  10. kv.sort('zset1'); // Output: ['member1', 'member2', 'member3']

  12. // add a few members to a list
  13. kv.rpush('list1', 'member1', 'member2', 'member3'); // Output: true
  14. // sort the members of a list
  15. kv.sort('list1'); // Output: ['member1', 'member2', 'member3']
  16. ```

smembers This method retrieves all the members of the set value stored at key.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3'); // Output: true
  4. // print the members of a set
  5. kv.smembers('set1'); // Output: ['member1', 'member2', 'member3']
  6. ```

spop Removes and returns one or multiple random members from a set.

  1. ``` js
  2. // add a few members to a set
  3. kv.sadd('set1', 'member1', 'member2', 'member3', ',member4', 'member5'); // Output: true
  4. // remove and return a random member from a set
  5. kv.spop('set1'); // Output: one of the members
  6. // remove and return a random member from a set
  7. kv.spop('set1', 2); // Output: two of the remaining members
  8. ```

ttl
  1. ``` js
  2. // Set key 'username' to 'heyputer' and set its expiration to 60 seconds
  3. kv.set('username', 'heyputer');
  4. kv.expire('username', 60);

  6. // Check the time-to-