Input validator for javascript based apps.
npm install smart-input-validator``
npm i -s smart-input-validator
Validator takes 3 parameters.
`js`
validator(inputs, rules, errorMessages);
- inputs is a key-value pair where the key is the field name and the value is the user input.
- rules is a key-value pair where the key is the field and the value will be the rules for the validation of that field. Each rules are separated by ; (note that there's a space after the semi-colon, that's important). Don't add spaces before and after , and :.
- errorMessages is a multi-dimension key-value pair, the first dimension is the field and the second dimension is another key-value pair where the key is the rule and the value is the error message that will be returned.
The general format is as follows:
`js`
let errors = validator(
// parameter 1 is user inputs
{
input1: "value1",
input2: "value2"
},
// parameter 2 is the rules for the inputs
{
input1: "rule1; rule2; rule3; rule4:value1,value2,value3; rule5:value1"
},
// parameter 3 is the error messages for the validations
{
input1: {
rule1: "error!",
rule2: "error!",
rule3: "error!",
rule4: "error!"
}
}
);
#### Example codes
`js
import validator from "smart-input-validator";
let errors = validator(
{
email: "invalid-email",
firstname: "",
password: "do",
confirm_password: "will-not-match"
},
{
email: "required; email",
firstname: "required; allowedChars:alphabets,spaces",
password: "required; min:8",
confirm_password: "required; equals:password"
},
{
email: {
required: "Please enter your email.",
email: "Your email is invalid."
},
firstname: {
required: "Please enter your first name.",
allowedChars: "Your first name is invalid."
},
password: {
required: "Please enter your password.",
min: "Your password is too short."
},
confirm_password: {
required: "Please enter your password again.",
equals: "Passwords do not match."
}
}
);
`
The variable errors above will be an array of error messages like so:
`js`
[
"Your email is invalid.",
"Please enter your first name.",
"Your password is too short.",
"Passwords do not match."
];
You can also have validations with the same error messages and only one will show.
`js
import validator from "smart-input-validator";
let errors = validator(
{
name: "a"
},
{
name: "required; allowedChars:alphabets,spaces; min:2"
},
{
name: {
required: "Please enter your name.",
allowedChars: "Your name is invalid.",
min: "Your name is invalid."
}
}
);
`
The error will be like so:
`
[
"Your name is invalid."
]
`js`
let errors = validator(
// parameter 1 is user inputs
{
input1: "value1",
input2: "value2"
},
// parameter 2 is the rules for the inputs
{
input1: "rule1; rule2; rule3; rule4:value1,value2,value3; rule5:value1"
},
// parameter 3 is the error messages for the validations
{
input1: {
rule1: "error!",
rule2: "error!",
rule3: "error!",
rule4: "error!"
}
}
);
#### Length related validations
- input1: 'exactLen:255' -- a field whose exact string length is 255.input1: 'minLen:8'
- -- a field whose minimum string length is 8.input1: 'maxLen:255'
- -- a field whose maximum string length is 255.input1: 'betweenLen:8,18'
- -- a field whose maximum string length is 18 and minimum string length is 8.
#### Value related validations
- input1: 'min:8' -- a numeric field whose minimum value is 8.input1: 'max:255'
- -- a numeric field whose maximum value is 255.input1: 'between:8,18'
- -- a numeric field whose value should be 8 to 18.input1: 'exactly:255'
- -- a numeric field whose value should be exactly 255.input1: 'required'
- -- a field that should not be an empty string.input1: 'email'
- -- a field that should be a valid email.input1: 'allowedChars:alphabets,spaces,numbers,decimals'
- -- a field that is restricted only to a particular set of characters. Accepted values are alphabets,spaces,numbers,decimals. Note that if you specify decimals you don't need to specify numbers.input1: 'notAllowedChars:alphabets,spaces,numbers,decimals'
- -- Similar to allowedChars, except you specify the character set that you don't allow.input1: 'in:choice 1,choice 2,choice 3,...n'
- -- a field that is restricted only to the available choices.
#### Equality related validations
- input1: 'equals:another_field' -- a field that is equal to another field. another_field could be a field in the fields parameter or an actual value.input1: 'regex:/([a-zA-Z])/'
- -- a field that has specific characters allowed. Note that regex is affirmative. That means error occurs if value.test(regex) == true.input1: 'notRegex:/([a-zA-Z])/'
- -- a field that has specific characters allowed. Note that notRegex is negative. That means error occurs if value.test(regex) == false.input1: 'bool'
- -- a field that should be a boolean.
_$all is a string that basically acts as the default error message that you can provide. If a field has an error and you did not provide an error message for that field, but the _$all was provided on that field, then it will use it.
- If you want two or more validation rules to have the same error messages.
You provide _$all in the error messages parameter.
`js
import validator from "smart-input-validator";
const errors = validator(
{
value1: "val",
value2: "val"
},
{
value1: "allowedChars:numbers; betweenLen:8,18; minLen:8",
value2: "allowedChars:numbers; betweenLen:8,18; minLen:8"
},
{
value1: {
allowedChars: "allowedChars error message for value1.",
betweenLen: "betweenLen error message for value1.",
minLen: "minLen error message for value1."
},
value2: {
betweenLen: "betweenLen error message for value2.",
betweenLen: "betweenLen error message for value2.",
minLen: "minLen error message for value2."
}
}
);
console.log(errors);
`
The codes above will fail because error messages for betweenLen and minLen are missing. But if you provide _$all:
`js
import validator from "smart-input-validator";
const errors = validator(
{
value1: "val",
value2: "val"
},
{
value1: "allowedChars:numbers; betweenLen:8,18; minLen:8",
value2: "allowedChars:numbers; betweenLen:8,18; minLen:8"
},
{
value1: {
allowedChars: "allowedChars error message for value1.",
_$all: "default custom error message for value1."
},
value2: {
betweenLen: "betweenLen error message for value2.",
_$all: "default custom error message for value2."
}
}
);
console.log(errors);
`
The codes above will now output:
`js`
[
"allowedChars error message for value1.",
"default custom error message for value1.",
"default custom error message for value2.",
"betweenLen error message for value2."
];
_$options is an object that can be added to the second parameter, which is the validation rules. It basically tells the validator how to behave.
`js
import validator from "smart-input-validator";
const errors = validator(
{
value1: "val",
value2: "val"
},
{
value1: "allowedChars:numbers; betweenLen:8,18; minLen:8",
value2: "allowedChars:numbers; betweenLen:8,18; minLen:8"
},
{
value1: {
allowedChars: "allowedChars error message for value1.",
betweenLen: "betweenLen error message for value1.",
minLen: "minLen error message for value1."
},
value2: {
betweenLen: "betweenLen error message for value2.",
betweenLen: "betweenLen error message for value2.",
minLen: "minLen error message for value1."
}
}
);
console.log(errors);
`
The codes above will output:
`js`
[
"allowedChars error message for value1.",
"value1 must be 8 to 18 characters long.",
"value1 must be at least 8 characters long.",
"value2 has invalid characters.",
"betweenLen error message for value2.",
"value2 must be at least 8 characters long."
];
This is the default behavior. If you provide _$options you can change the way it behaves. _$options can be provided like so:
`js
import validator from "smart-input-validator";
const errors = validator(
{
value1: "val",
value2: "val"
},
{
value1: "allowedChars:numbers; betweenLen:8,18; minLen:8",
value2: "allowedChars:numbers; betweenLen:8,18; minLen:8",
_$options: {
stopAtFirstError: true
}
},
{
value1: {
allowedChars: "allowedChars error message for value1.",
betweenLen: "betweenLen error message for value1.",
minLen: "minLen error message for value1."
},
value2: {
betweenLen: "betweenLen error message for value2.",
betweenLen: "betweenLen error message for value2.",
minLen: "minLen error message for value2."
}
}
);
console.log(errors);
`
The codes above will ouput:
`js`
["allowedChars error message for value1.", "value2 has invalid characters."];
- _$options.stopAtFirstError` -- not required -- tells the validator to stop at the very first error occurrence, so if an error was encountered on the very first occurrence, the validation will stop there and move to validated the next field.
If you have a new feature request, feature enhancement request, bug report, clarification, or if you have something you want to point out about the docs, feel free to open an issue or send a PR.
MIT