Package 'shinyvalidate' reference manual

Title:	Input Validation for Shiny Apps
Description:	Improves the user experience of Shiny apps by helping to provide feedback when required inputs are missing, or input values are not valid.
Authors:	Carson Sievert [aut, cre] , Richard Iannone [aut] , Joe Cheng [aut], Posit Software, PBC [cph, fnd]
Maintainer:	Carson Sievert <[email protected]>
License:	MIT + file LICENSE
Version:	0.1.3.9000
Built:	2024-11-03 04:20:32 UTC
Source:	https://github.com/rstudio/shinyvalidate

Combine shinyvalidate rule functions

Description

Takes multiple shinyvalidate rule functions, and returns a shinyvalidate rule function. When this resulting rule function is invoked, it will try each of its constituent rule functions in order; the first validation error that is detected will be returned immediately and the remaining rules will not be tried.

This function is not intended to be used by Shiny app authors (i.e. not for InputValidator$add_rule("x", compose_rules(...))), but for developers of reusable shinyvalidate rule functions. See examples.

Usage

compose_rules(...)
compose_rules(...)

Arguments

...

Any number of shinyvalidate rule functions; earlier rules will be attempted before later rules. Argument names are ignored. Single-sided formulas are also accepted instead of a function, using . as the variable name for the input value.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

# Create a new shinyvalidate rule that is composed
# of two `sv_*()` rule functions (`sv_integer()` and
# `sv_gt()`, and a custom function for ensuring
# a number is even)
positive_even_integer <- function() {
  compose_rules(
    sv_integer(),
    sv_gt(0),
    ~ if (. %% 2 == 1) "Must be an even number"
  )
}

# Use the `positive_even_integer()` rule function
# to check that a supplied value is an integer, greater
# than zero, and even (in that order)

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("value", "Value")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Add two `add_rule()` statements: one that
  # combines `sv_required()` and `sv_numeric()` in
  # single rule, and another that is defined
  # through the use of `compose_rules()`
  iv$add_rule("value", compose_rules(sv_required(), sv_numeric()))
  iv$add_rule("value", positive_even_integer())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

# Create a new shinyvalidate rule that is composed
# of two `sv_*()` rule functions (`sv_integer()` and
# `sv_gt()`, and a custom function for ensuring
# a number is even)
positive_even_integer <- function() {
  compose_rules(
    sv_integer(),
    sv_gt(0),
    ~ if (. %% 2 == 1) "Must be an even number"
  )
}

# Use the `positive_even_integer()` rule function
# to check that a supplied value is an integer, greater
# than zero, and even (in that order)

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("value", "Value")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Add two `add_rule()` statements: one that
  # combines `sv_required()` and `sv_numeric()` in
  # single rule, and another that is defined
  # through the use of `compose_rules()`
  iv$add_rule("value", compose_rules(sv_required(), sv_numeric()))
  iv$add_rule("value", positive_even_integer())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Check whether an input value has been provided

Description

This function takes an input value and uses heuristics to guess whether it represents an "empty" input vs. one that the user has provided. This will vary by input type; for example, a shiny::textInput() is "" when empty, while a shiny::numericInput() is NA.

input_provided returns TRUE for all values except:

NULL
""
An empty atomic vector or list
An atomic vector that contains only missing (NA) values
A character vector that contains only missing and/or "" values
An object of class "try-error"
A value that represents an unclicked shiny::actionButton()

Usage

input_provided(val)
input_provided(val)

Arguments

val

Values to test for availability in a Shiny context.

Details

This function is based on shiny::isTruthy() but tweaked here in shinyvalidate to change the treatment of FALSE values: isTruthy(FALSE) returns FALSE, but input_provided(FALSE) returns TRUE. This difference is motivated by shiny::checkboxInput(), where isTruthy() answers the question of "is the input present and checked" while input_provided is just "is the input present".

Value

A logical vector of length 1.

Shiny validation object

Description

An R6 class for adding realtime input validation to Shiny apps.

InputValidator objects are designed to be created as local variables in Shiny server functions and Shiny module server functions. The Shiny app author can register zero, one, or multiple validation rules for each input field in their UI, using the InputValidator$add_rule() method.

Once an InputValidator object is created and populated with rules, it can be used in a few ways:

The InputValidator$enable() method can be called to display real-time feedback to users about what inputs are failing validation, and why.
The InputValidator$is_valid() method returns TRUE if and only if all of the validation rules are passing; this can be checked before executing actions that depend on the inputs being valid.
The InputValidator$validate() method is a lower-level feature that directly returns information about what fields failed validation, and why.

It's possible to have multiple InputValidator objects for each Shiny app. One scenario where this makes sense is if an app contains multiple forms that are completely unrelated to each other; each form would have its own InputValidator instance with a distinct set of rules.

Methods

Method `new()`

Create a new validator object.

Usage

InputValidator$new(
  priority = 1000,
  session = shiny::getDefaultReactiveDomain()
)

Arguments

priority: When a validator object is enabled, it creates an internal shiny::observe() to keep validation feedback in the UI up-to-date. This parameter controls the priority of that observer. It's highly recommended to keep this value higher than the priorities of any observers that do actual work, so users see validation updates quickly.
session: The Shiny session object. (You should probably just use the default.)

Method `parent()`

For internal use only.

Usage

InputValidator$parent(validator)

Arguments

validator: An InputValidator object.

Method `condition()`

Gets or sets a condition that overrides all of the rules in this validator. Before performing validation, this validator will execute the cond function. If cond returns TRUE, then validation continues as normal; if FALSE, then the validation rules will be skipped and treated as if they are all passing.

Usage

InputValidator$condition(cond)

Arguments

cond: If this argument is missing, then the method returns the currently set condition function. If not missing, then cond must be either a zero-argument function that returns TRUE or FALSE; a single-sided formula that results in TRUE or FALSE; or NULL (which is equivalent to ~ TRUE).

Returns

If cond is missing, then either NULL or a zero-argument function; if cond is provided, then nothing of consequence is returned.

Method `add_validator()`

Add another InputValidator object to this one, as a "child". Any time this validator object is asked for its validity, it will only return TRUE if all of its child validators are also valid; and when this validator object is enabled (or disabled), then all of its child validators are enabled (or disabled) as well.

This is intended to help with validating Shiny modules. Each module can create its own InputValidator object and populate it with rules, then return that object to the caller.

Usage

InputValidator$add_validator(validator, label = deparse(substitute(validator)))

Arguments

validator: An InputValidator object.
label: An optional label for the InputValidator object. By default, a label will be automatically generated.

Method `add_rule()`

Add an input validation rule. Each input validation rule applies to a single input. You can add multiple validation rules for a single input by calling add_rule() multiple times; the first validation rule for an input that fails will be used, and will prevent subsequent rules for that input from executing.

Usage

InputValidator$add_rule(
  inputId,
  rule,
  ...,
  session. = shiny::getDefaultReactiveDomain()
)

Arguments

inputId: A single-element character vector indicating the ID of the input that this rule applies to. (Note that this name should not be qualified by a module namespace; e.g. pass "x" and not session$ns("x").)
rule: A function that takes (at least) one argument: the input's value. The function should return NULL if it passes validation, and if not, a single-element character vector or HTML tag containing an error message to display to the user near the input. You can alternatively provide a single-sided formula instead of a function, using . as the variable name for the input value being validated.
...: Optional: Additional arguments to pass to the rule function whenever it is invoked.
session.: The session object to which the input belongs. (There's almost never a reason to change this from the default.)

Method `enable()`

Begin displaying input validation feedback in the user interface. Once enabled, this validator object will automatically keep the feedback up-to-date. (It's safe to call the enable() method on an already-enabled validator.) If this validator object has been added to another validator object using InputValidator$add_validator, calls to enable() on this validator will be ignored.

Usage

InputValidator$enable()

Method `disable()`

Clear existing input validation feedback in the user interface for all inputs represented in this validator's ruleset, and stop providing feedback going forward. Once disabled, enable() can be called to resume input validation.

Usage

InputValidator$disable()

Method `fields()`

Returns TRUE if all input validation rules currently pass, FALSE if not.

Usage

InputValidator$fields()

Method `is_valid()`

Returns TRUE if all input validation rules currently pass, FALSE if not.

Usage

InputValidator$is_valid()

Method `validate()`

Run validation rules and gather results. For advanced usage only; most apps should use the is_valid() and enable() methods instead. The return value of this method is a named list, where the names are (fully namespace qualified) input IDs, and the values are either NULL (if the input value is passing) or a single-element character vector describing a validation problem.

Usage

InputValidator$validate()

Method `_validate_impl()`

For internal use only.

Usage

InputValidator$_validate_impl(indent)

Arguments

indent: For internal use only.

Skip any normal validation performed by a rule

Description

While the predominant role of the skip_validation() function is tied to the sv_optional() function (where it's used internally), you can also return skip_validation() from custom validation rules. When returned, all subsequent validation rules defined for the input will be skipped.

Usage

skip_validation()
skip_validation()

Value

A function that returns a sentinel value, signaling to shinyvalidate that any further validation rules for an input are to be skipped.

Validate that a field is a number bounded by minimum and maximum values

Description

The sv_between() function validates that a field has values between left and right boundary values. Both bounds are inclusive by default, but both can be set as either inclusive or exclusive with the inclusive argument. In its default mode, the validation check will effectively be of the form ⁠<left> <= <field> <= <right>⁠.

Usage

sv_between(
  left,
  right,
  inclusive = c(TRUE, TRUE),
  message_fmt = "Must be between {left} and {right}.",
  allow_na = FALSE,
  allow_nan = FALSE
)
sv_between(
  left,
  right,
  inclusive = c(TRUE, TRUE),
  message_fmt = "Must be between {left} and {right}.",
  allow_na = FALSE,
  allow_nan = FALSE
)

Arguments

`left`, `right`	The left and right boundary values. Inclusively for each of the boundaries is set with the `inclusive` argument; the defaults are set for inclusive bounds.
`inclusive`	A two-element logical vector that indicates whether the `left` and `right` bounds, respectively, should be inclusive. Both bounds are by default are inclusive, using `c(TRUE, TRUE)`.
`message_fmt`	The validation error message to use if a value fails to match the rule. The message can be customized by using the `"{left}"` and `"{right}"` string parameters, which allows for the insertion of the `left` and `right` values. While the default message uses both of these string parameters, they are not required in a user-defined `message_fmt` string.
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("count", "Count")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_between()` requires `left` and
  # `right` boundary values; a message will be
  # displayed if the validation of `input$count` fails
  iv$add_rule("count", sv_between(10, 100))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("count", "Count")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_between()` requires `left` and
  # `right` boundary values; a message will be
  # displayed if the validation of `input$count` fails
  iv$add_rule("count", sv_between(10, 100))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field contains an email address

Description

A validation function, suitable for use with InputValidator$add_rule(), that checks whether an input value looks like a valid email address.

Usage

sv_email(
  message = "Not a valid email address",
  allow_multiple = FALSE,
  allow_na = FALSE
)
sv_email(
  message = "Not a valid email address",
  allow_multiple = FALSE,
  allow_na = FALSE
)

Arguments

`message`	The validation error message to use if a value doesn't match a regex pattern for email address detection.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`	If `FALSE`, then any `NA` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("email", "Email")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_email()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$email` fails
  iv$add_rule("email", sv_email())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("email", "Email")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_email()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$email` fails
  iv$add_rule("email", sv_email())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is equal to a specified value

Description

The sv_equal() function compares the field value to a specified value with the == operator.

Usage

sv_equal(
  rhs,
  message_fmt = "Must be equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_equal(
  rhs,
  message_fmt = "Must be equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> == <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_equal()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_equal(1))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_equal()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_equal(1))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is greater than a specified value

Description

The sv_gt() function compares the field value to a specified value with the > operator.

Usage

sv_gt(
  rhs,
  message_fmt = "Must be greater than {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_gt(
  rhs,
  message_fmt = "Must be greater than {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> > <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_gt()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_gt(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_gt()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_gt(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is greater than or equal to a specified value

Description

The sv_gte() function compares the field value to a specified value with the >= operator.

Usage

sv_gte(
  rhs,
  message_fmt = "Must be greater than or equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_gte(
  rhs,
  message_fmt = "Must be greater than or equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> >= <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_gte()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_gte(1))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_gte()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_gte(1))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is part of a defined set

Description

The sv_in_set() function checks whether the field value is a member of a specified set of values.

Usage

sv_in_set(
  set,
  message_fmt = "Must be in the set of {values_text}.",
  set_limit = 3
)
sv_in_set(
  set,
  message_fmt = "Must be in the set of {values_text}.",
  set_limit = 3
)

Arguments

`set`	A vector or list of elements for which the field value must be a part of (`value %in% set` must be `TRUE`) to pass validation. To allow an empty field, `NA` should be included in the `set` vector. Optionally, `NaN` can be included as well.
`message_fmt`	The validation error message to use if a value fails to match the rule. The message can be customized by using the `"{values_text}"` string parameter, which allows for the insertion of `set` values (formatted internally as a text list and controlled via the `set_limit` parameter). While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`set_limit`	The limit of `set` values to include in the automatically-generated error message (i.e., when `message = NULL`, the default). If the number of elements provided in `set` is greater than `set_limit` then only the first `⁠<message_limit>⁠` set elements will be echoed along with text that states how many extra elements are part of the `set`.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("rating", "Rating")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_in_set()` requires a value
  # set given as a vector; a message will be
  # shown if the validation of `input$rating` fails
  iv$add_rule("rating", sv_in_set(1:5))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("rating", "Rating")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_in_set()` requires a value
  # set given as a vector; a message will be
  # shown if the validation of `input$rating` fails
  iv$add_rule("rating", sv_in_set(1:5))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is a number that is integer-like

Description

The sv_integer() function validates that a field is 'integer-like' with the {value} %% 1 == 0 test. Very large values (generally with absolute exponent values greater than 15) won't be validated correctly due to floating point imprecision. By default, only a single, finite, not-missing, valid numbers are allowed, but each of those criteria can be controlled via arguments.

Usage

sv_integer(
  message = "An integer is required",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE
)
sv_integer(
  message = "An integer is required",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE
)

Arguments

`message`	The validation error message to use if a value is not an integer.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("count", "Count")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_integer()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$count` fails
  iv$add_rule("count", sv_integer())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("count", "Count")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_integer()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$count` fails
  iv$add_rule("count", sv_integer())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is less than a specified value

Description

The sv_lt() function compares the field value to a specified value with the < operator.

Usage

sv_lt(
  rhs,
  message_fmt = "Must be less than {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_lt(
  rhs,
  message_fmt = "Must be less than {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> < <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_lt()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_lt(10))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_lt()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_lt(10))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is less than or equal to a specified value

Description

The sv_lte() function compares the field value to a specified value with the <= operator.

Usage

sv_lte(
  rhs,
  message_fmt = "Must be less than or equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_lte(
  rhs,
  message_fmt = "Must be less than or equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> <= <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_lte()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_lte(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("number", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_lte()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$number` fails
  iv$add_rule("number", sv_lte(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is not equal to a specified value

Description

The sv_not_equal() function compares the field value to a specified value with the != operator.

Usage

sv_not_equal(
  rhs,
  message_fmt = "Must not be equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_not_equal(
  rhs,
  message_fmt = "Must not be equal to {rhs}.",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`rhs`	The right hand side (RHS) value is to be used for the comparison with the field value. The validation check will effectively be of the form `⁠<field> != <rhs>⁠`.
`message_fmt`	The validation error message to use if the field fails the validation test. Use the `"{rhs}"` string parameter to customize the message, including what was set in `rhs`. While the default message uses this string parameter, it is not required in a user-defined `message_fmt` string.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("score", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_not_equal()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$score` fails
  iv$add_rule("score", sv_not_equal(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("score", "Number")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_not_equal()` requires a value
  # to compare against the field value; a message
  # will be shown if the validation of
  # `input$score` fails
  iv$add_rule("score", sv_not_equal(0))

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field is a number

Description

The sv_numeric() function validates that a field is numeric with the base::is.numeric() function. By default, only a single, finite, not-missing, valid number is allowed, but each of those criteria can be controlled via arguments.

Usage

sv_numeric(
  message = "A number is required",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)
sv_numeric(
  message = "A number is required",
  allow_multiple = FALSE,
  allow_na = FALSE,
  allow_nan = FALSE,
  allow_inf = FALSE
)

Arguments

`message`	The validation error message to use if a value is not numeric.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`, `allow_nan`	If `FALSE` (the default for both options), then any `NA` or `NaN` element will cause validation to fail.
`allow_inf`	If `FALSE` (the default), then any `Inf` or `-Inf` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("rating", "Rating")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_numeric()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$rating` fails
  iv$add_rule("rating", sv_numeric())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("rating", "Rating")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_numeric()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$rating` fails
  iv$add_rule("rating", sv_numeric())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Indicate that a field is optional

Description

Call sv_optional() to generate a validation function that indicates an input is allowed to not be present. If an sv_optional() rule sees that an input is not present, subsequent rules for that input are skipped and the input is considered valid. Otherwise, the rule simply passes. (sv_optional() will never return a validation error/message.)

By default, the definition of "is present" is based on input_provided().

Child validators (see InputValidator$add_validator()) are not affected by sv_optional() rules in parent validators; only rules in the same validator instance as the sv_optional() will be skipped.

Usage

sv_optional(test = input_provided)
sv_optional(test = input_provided)

Arguments

test

A single-argument function, or single-sided formula (using . to access the value to test), that returns TRUE for success and FALSE for failure.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("email", "Email")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_optional()` is often paired with
  # another `sv_*()` function; below, an email in
  # `input$email` is not required, but if present, it
  # must be valid
  iv$add_rule("email", sv_optional())
  iv$add_rule("email", sv_email())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("email", "Email")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_optional()` is often paired with
  # another `sv_*()` function; below, an email in
  # `input$email` is not required, but if present, it
  # must be valid
  iv$add_rule("email", sv_optional())
  iv$add_rule("email", sv_email())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Validate that a field matches a regular expression

Description

A validation function, suitable for use with InputValidator$add_rule(), that checks whether input values match the specified regular expression.

Usage

sv_regex(
  pattern,
  message,
  ignore.case = FALSE,
  perl = FALSE,
  fixed = FALSE,
  useBytes = FALSE,
  invert = FALSE
)
sv_regex(
  pattern,
  message,
  ignore.case = FALSE,
  perl = FALSE,
  fixed = FALSE,
  useBytes = FALSE,
  invert = FALSE
)

Arguments

`pattern`	Character string containing a regular expression (or character string if `fixed = TRUE`) to be tested against. If a character vector of length 2 or more is supplied, the first element is used with a warning.
`message`	The validation error message to use if a value fails to match the pattern.
`ignore.case`, `perl`, `fixed`, `useBytes`, `invert`	Options passed through to `base::grepl()`.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("lookup_id", "Lookup ID")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_regex()` requires both a regex
  # pattern and message to display if the validation
  # of `input$lookup_id` fails
  iv$add_rule(
    "lookup_id",
    sv_regex("^[a-zA-Z0-9]*$", "Only alphanumeric characters allowed")
  )

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

# As an alternative to the above example, the
# following snippet can serve to replace the
# `iv$add_rule(...)` statement

# If you're more comfortable with wildcards
# (i.e., globbing) than with regular expressions,
# use `glob2rx()` in `pattern`

# iv$add_rule(
#   "lookup_id",
#   sv_regex(
#     pattern = glob2rx("*.png"),
#     message = "A filename ending in 'png' was expected",
#     ignore.case = TRUE
#   )
# )

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("lookup_id", "Lookup ID")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_regex()` requires both a regex
  # pattern and message to display if the validation
  # of `input$lookup_id` fails
  iv$add_rule(
    "lookup_id",
    sv_regex("^[a-zA-Z0-9]*$", "Only alphanumeric characters allowed")
  )

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

# As an alternative to the above example, the
# following snippet can serve to replace the
# `iv$add_rule(...)` statement

# If you're more comfortable with wildcards
# (i.e., globbing) than with regular expressions,
# use `glob2rx()` in `pattern`

# iv$add_rule(
#   "lookup_id",
#   sv_regex(
#     pattern = glob2rx("*.png"),
#     message = "A filename ending in 'png' was expected",
#     ignore.case = TRUE
#   )
# )

Validate that the field is present

Description

Call sv_required() to generate a validation function that ensures an input value is present. By default, the definition of "is present" is based on input_provided().

Usage

sv_required(message = "Required", test = input_provided)
sv_required(message = "Required", test = input_provided)

Arguments

`message`	The validation error message to be displayed if the test does not pass.
`test`	A single-argument function, or single-sided formula (using `.` to access the value to test), that returns `TRUE` for success and `FALSE` for failure.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("name", "Name")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: ensure that `input$name` is present,
  # and return a terse validation message if not
  iv$add_rule("name", sv_required())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

# There are some alternatives to the above example,
# and the following snippets can serve to replace
# the `iv$add_rule(...)` statement

# (1) Providing a custom message to display
# when validation fails:

# iv$add_rule("email", sv_required("An email is required"))

# (2) Providing a `test` argument to change
# the definition of "is present"; in this
# snippet, any non-NULL value will be accepted:

# iv$add_rule("choices", sv_required(test = is.null))

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("name", "Name")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: ensure that `input$name` is present,
  # and return a terse validation message if not
  iv$add_rule("name", sv_required())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

# There are some alternatives to the above example,
# and the following snippets can serve to replace
# the `iv$add_rule(...)` statement

# (1) Providing a custom message to display
# when validation fails:

# iv$add_rule("email", sv_required("An email is required"))

# (2) Providing a `test` argument to change
# the definition of "is present"; in this
# snippet, any non-NULL value will be accepted:

# iv$add_rule("choices", sv_required(test = is.null))

Validate that a field contains a URL

Description

A validation function, suitable for use with InputValidator$add_rule(), that checks whether an input value is a valid URL.

Usage

sv_url(message = "Not a valid URL", allow_multiple = FALSE, allow_na = FALSE)
sv_url(message = "Not a valid URL", allow_multiple = FALSE, allow_na = FALSE)

Arguments

`message`	The validation error message to use if a value doesn't match a regex pattern for URL detection.
`allow_multiple`	If `FALSE` (the default), then the length of the input vector must be exactly one; if `TRUE`, then any length is allowed (including a length of zero; use `sv_required()` if one or more values should be required).
`allow_na`	If `FALSE`, then any `NA` element will cause validation to fail.

Value

A function suitable for use as an InputValidator$add_rule() rule.

Examples

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("url", "URL")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_url()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$address` fails
  iv$add_rule("url", sv_url())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

## Only run examples in interactive R sessions
if (interactive()) {

library(shiny)
library(shinyvalidate)

ui <- fluidPage(
  textInput("url", "URL")
)

server <- function(input, output, session) {
  
  # Validation rules are set in the server, start by
  # making a new instance of an `InputValidator()`
  iv <- InputValidator$new()

  # Basic usage: `sv_url()` works well with its
  # defaults; a message will be displayed if the
  # validation of `input$address` fails
  iv$add_rule("url", sv_url())

  # Finally, `enable()` the validation rules
  iv$enable()
}

shinyApp(ui, server)

}

Package 'shinyvalidate'

Help Index

Combine shinyvalidate rule functions

Description

Usage

Arguments

Value

See Also

Examples

Check whether an input value has been provided

Description

Usage

Arguments

Details

Value

Shiny validation object

Description

Methods

Public methods

Method new()

Usage

Arguments

Method parent()

Usage

Arguments

Method condition()

Usage

Arguments

Returns

Method add_validator()

Usage

Arguments

Method add_rule()

Usage

Arguments

Method enable()

Usage

Method disable()

Usage

Method fields()

Usage

Method is_valid()

Usage

Method validate()

Usage

Method _validate_impl()

Usage

Arguments

Skip any normal validation performed by a rule

Description

Usage

Value

Validate that a field is a number bounded by minimum and maximum values

Description

Usage

Arguments

Value

See Also

Examples

Validate that a field contains an email address

Description

Usage

Arguments

Value

See Also

Examples

Validate that a field is equal to a specified value

Description

Usage

Arguments

Value

See Also

Examples

Validate that a field is greater than a specified value

Description

Usage

Arguments

Value

See Also

Examples

Method `new()`

Method `parent()`

Method `condition()`

Method `add_validator()`

Method `add_rule()`

Method `enable()`

Method `disable()`

Method `fields()`

Method `is_valid()`

Method `validate()`

Method `_validate_impl()`