ObjectDigest

Information summary object

You can use the Digest object like this:

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const crypto = require('crypto');
// create a SHA-512 digest object
const digest = crypto.createHash('sha512');
// update digest with data
digest.update('hello');
digest.update('world');
// get digest result
const result = digest.digest();
console.log(result);

// output result in hex and base64
console.log(result.toString('hex'));
console.log(result.toString('base64'));

In the above code, crypto.createHash()a SHA-512 digest operation object is created using the method. update()The data to be summarized can be gradually added through the method, and digest()the summary result can be obtained through the method.

inheritance relationship

member properties

size

Integer, query the number of digest bytes of the current information digest algorithm

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readonly Integer Digest.size;

member function

update

Update binary digest information

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Digest Digest.update(Buffer data);

Call parameters:

• data:Buffer, binary data block

Return results:

• Digest, returns the information summary object itself

---

Update string summary information

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Digest Digest.update(String data,
    String codec = "utf8");

Call parameters:

• data: String, string data
• codec: String, specifies the encoding format, allowed values ​​are: "buffer", "hex", "base32", "base58", "base64", "utf8", oriconvCharacter sets supported by the module

Return results:

• Digest, returns the information summary object itself

---

digest

Compute and return summary

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Value Digest.digest(String codec = "buffer");

Call parameters:

• codec: String, specifies the encoding format, allowed values ​​are: "buffer", "hex", "base32", "base58", "base64", "utf8", oriconvCharacter sets supported by the module

Return results:

• Value, returns a summary representation of the specified encoding

---

sign

Sign and return summary

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Buffer Digest.sign(PKey key,
    Object opts = {}) async;

Call parameters:

• key:PKey, signed private key
• opts: Object, specify signature options

Return results:

• Buffer, return the signed data

opts supports the following parameters:

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{
    alg: 0 指定签名的 hash 算法， 仅在 RSA 时有效， 缺省为 0. 支持算法: 0 = NONE,
    1 = MD5,
    2 = SHA1,
    3 = SHA224,
    4 = SHA256,
    5 = SHA384,
    6 = SHA512,
    7 = RIPEMD160
}

---

verify

Verify signatures are consistent

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Boolean Digest.verify(PKey key,
    Buffer sign,
    Object opts = {}) async;

Call parameters:

• key:PKey, the public key to verify the signature
• sign:Buffer, specify the signature to be verified
• opts: Object, specify verification options

Return results:

• Boolean, returns the verified result

opts supports the following parameters:

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{
    alg: 0 指定签名的 hash 算法， 仅在 RSA 时有效， 缺省为 0. 支持算法: 0 = NONE,
    1 = MD5,
    2 = SHA1,
    3 = SHA224,
    4 = SHA256,
    5 = SHA384,
    6 = SHA512,
    7 = RIPEMD160
}

---

toString

Returns the string representation of the object. Generally, "[Native Object]" is returned. The object can be re-implemented according to its own characteristics.

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String Digest.toString();

Return results:

• String, returns the string representation of the object

---

toJSON

Returns a JSON format representation of the object, generally returning a collection of readable properties defined by the object.

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Value Digest.toJSON(String key = "");

Call parameters:

• key: String, not used

Return results:

• Value, returns a value containing JSON serializable