Advanced Redis or redisio

redis.md

Redis Methods:

Single key-value pairs set/get karne ke liye use hota hai.

-- set/get => data store in string format

-- hset/hget/hgetall:

• Data store in Object format
• Used in store userProfile to get data fast not db calls and if any update invalidate data.

1. SET/set: await redisClient.set(`user:${req.params.id}:json`, JSON.Stringfy(objData), "EX", 300);
2. GET/get: const storedOtp = await redisClient.get(otpKey(phone));

Multiple key-value pairs set/get karne ke liye use hota hai.

4. MSET/mSet:

   await redisClient.mSet({
       name: "Alice",
       city: "Mumbai",
       role: "Developer",
       }); 
   

5. MGET/mGet:

   const values = await redisClient.mGet([
        "name",
        "city",
        "role",
      ]);
   
    Output: ["Alice", "Mumbai", "Developer"] as Array
   

• Important

  • MSET me TTL set nahi kar sakte.

• Why use MSET?

  • Multiple network round trips avoid hote hain.
  • Performance better hoti hai.
  • Ek command me multiple keys set ho jati hain.

Redis ke Hash data structure ke commands hain | Hash ko JavaScript object ki tarah samjho.

// 1. set => JSON.stringify(data) and get => JSON.parse(data)

app.post("/user/:id/json", async (req, res) => {
    const { id } = req.params;
    const { name, email, age, city } = req.body;
    if(!id){
        return res.status(400).json({ success: false, error: "User ID is required!" });
    }
    const user = { id, name, email, age, city };
    const key = `user:${id}:json`;
    await redisClient.set(key, JSON.stringify(user), 'EX', 100);
    return res.status(200).json({ success: true, data: "User created successfully" });
});

// Get whole string  
app.get("/user/:id/json", async (req, res) => {
    const { id } = req.params;
    const key = `user:${id}:json`;
    const user = await redisClient.get(key);
    return res.status(200).json({ success: true, data: JSON.parse(user) }); // Need to parse JSON and replace whole data of string
});

// delete the whole string 
app.delete("/user/:id/json", async (req, res) => {
    const { id } = req.params;
    const key = `user:${id}:json`;
    await redisClient.del(key);
    return res.status(200).json({ success: true, data: "User deleted successfully" });
});

// 2. HSET => store user profile as hash map
app.post("/user/:id/hset", async (req, res) => {
    const { id } = req.params;
    const { name, email, age, city } = req.body;
    if(!id){
        return res.status(400).json({ success: false, error: "User ID is required!" });
    }
    const user = { id, name, email, age, city };
    const key = `user:${id}:hash`;
    await redisClient.hset(key, user);
    return res.status(200).json({ success: true, data: "User created successfully" });
});

// Get whole hash | object map of user
app.get("/user/:id/hget", async (req, res) => {
    const { id } = req.params;
    const key = `user:${id}:hash`;
    const user = await redisClient.hgetall(key);
    return res.status(200).json({ success: true, data: user }); // No need to parse and modify key value objects
});

// delete the whole hash | object
app.delete("/user/:id/hdel", async (req, res) => {
    const { id } = req.params;
    const key = `user:${id}:hash`;
    await redisClient.del(key);
    return res.status(200).json({ success: true, data: "User deleted successfully" });
});

// Update Object
app.put("/user/:id/hset", async (req, res) => {
    const { id } = req.params;
    const { name, email, age, city } = req.body;
    if(!id){
        return res.status(400).json({ success: false, error: "User ID is required!" });
    }
    const user = { id, name, email, age, city };
    const key = `user:${id}:hash`;
    await redisClient.hset(key, user);
    return res.status(200).json({ success: true, data: "User updated successfully" });
});

10. HDEL/hdel:

    await redisClient.hdel("user:1");
    

11. HEXISTS/hexists:

     const isExists = await redisClient.hexists(
        "user:1"
      );
    
      console.log(Boolean(isExists));