Generates a map with keys :blank, :some and :any containing vectors of randomly selected, unique names which fit into certain categories, accordingly: required keys which must be blank, required keys which must not be blank, required keys which may have any value.

Data for randomization is taken from a map under the key :required/cat and from a vector under the key :required/special of the provided configuration argument. This vector is randomized to get a list of items values marked in validators configuration as special (coming from :required/blank, :required/some or :required keys, without its validation function being overriden by any manually configured validator). When the list is ready its items are grouped by the mentioned categories and returned as a map.

The optional second argument items is a number of items to generate. The optional third argument rng should be a random number generator object.

Generates a list of randomly selected, unique names from a vector which should be available under the key :required/blank of the provided map.

The optional second argument items is a number of items to generate. The optional third argument rng should be a random number generator object.

Generates a list of randomly selected, unique names from a vector which should be available under the key :required/some of the provided map.

The optional second argument items is a number of items to generate. The optional third argument rng should be a random number generator object.

Prepares validators configuration.

Sequences of values provided under :required/some, :required/blank and :required keys are cleaned-up and transformed into strings. Map under the key :validators is also transformed: its keys are converted into strings and values are dereferenced if they are symbols.

Any parameter in a sequence provided under :required/some or :required/blank key is removed if it has a custom validator assigned in :validators map.

Parameter names which exist in both :required/some and :required/blank sequences are removed from them and moved to a sequence under the :required/any key. Marking some required parameter to be blank and non-blank at the same time causes it to fall into a category where is can have any value to be considered valid.

Parameter names which exist in :required sequence and also exist in :required/some or :required/blank sequence are removed from the :required sequence.

Parameter names which exist in :required/some, :required/blank and :required are removed from :required/some and :required/blank, and only exist in :required. Unless their validator was already specified in :validators they are also added to :required/any.

For each parameter name from :required/some a validator is generated (checking if a given value is not blank). For each parameter name from :required/blank a validator is generated (checking if a given value is blank). For each parameter name from :required/any a validator is generated (accepting any value, including blanks).

Manually assigned validators are expressed as a map under :validators key.

Automatically created validators (for the aforementioned keys: :required/some, :required/blank and :required/any) are associated with their parameter names in a map under the :validators/all key, which also contains manually assigned validators.

During the operation a map is created under the :required/cat key. It contains all of the required parameter names as keys with validation categories assigned (expressed as keywords):

• :some – parameter is valid if it has a non-blank value
• :blank – parameter is valid if it has a blank value
• :any – parameter is valid if it has any value
• :custom – parameter is valid if it passes a custom validation (see :validators).

This function returns a given configuration map with the following keys transformed as described earlier:

Booleans: * :enabled? (true if enabled in configuration with :enabled?) * :default-pass? (true if unknown parameters are considered valid) * :check-required? (true if required parameters are to be checked)

Vectors: * :required/some (required parameters having auto-generated validators for non-blanks) * :required/blank (required parameters having auto-generated validators for blanks) * :required/any (required parameters having auto-generated validators for any values) * :required/special (all required parameters having auto-generated validators) * :required/user (required parameters which were manually configured) * :required (all required parameters, including those having auto-generated validators)

Maps: * :required/cat (all required parameters with categories assigned) * :validators (manually configured validators for parameter names) * :validators/all (manually and automatically configured validators)

Keywords: * :result-key (key identifying validation results in a request map) * :config-key (key identifying configuration in a request map) * :required/source (required parameters source, a keyword, defaults to :required/user) * :required/mode (required parameters checking mode: :all (default), :one or a number).

Validators wrapping middleware initializer. Processes the configuration expressed as a map which may have the following keys specified:

Switches: * :enabled? (true if enabled in configuration with :enabled?) * :default-pass? (true if unknown parameters are considered valid) * :check-required? (true if required parameters are to be checked)

Sequential collections: * :required/some (parameters which should have generated validators for non-blanks) * :required/blank (parameters which should have generated validators for blanks) * :required/any (parameters which should have generated validators for any values) * :required/user (parameters associated with the :required key) * :required/special (parameters for which validator was automatically generated) * :required/nospecial (parameters for which validator was not automatically generated) * :required (all required parameters)

Maps: * :validators (validators assigned to parameter names)

Keywords: * :result-key (key identifying validation results in a request map) * :config-key (key identifying configuration in a request map).

Validator names should be strings or objects which are convertible to strings. Validators can be various objects, see io.randomseed.utils.validators/Validating protocol.

The result of calling this function is a map intended to be used with Reitit router as a middleware. The handler function itself will add :validators/config and :validators/params-valid? entries to a request map. Names of these identifying keys can be changed by setting :result-key and/or :config-key configuration options.

The presence of validation function can be controlled by setting :validators/disabled? in a request context to override the defaults. It is a switch which disables the validation completely (any parameter will be considered valid).

By default, only manually configured required validators (assigned to the :required/user configuration key) will be checked for presence! It can be changed by setting :required/check to:

• :required/some (parameters which should have generated validators for non-blanks)
• :required/blank (parameters which should have generated validators for blanks)
• :required/any (parameters which should have generated validators for any values)
• :required/user (parameters associated with the :required key)
• :required/special (parameters for which validator was automatically generated)
• :required/nospecial (parameters for which validator was not automatically generated)
• :required (all required parameters)

See amelinium.http.middleware.validators/prep-validators to see the detailed logic behind preparing the configuration.