Data::Sah::CoerceCommon - Common stuffs for Data::Sah::Coerce and Data::Sah::CoerceJS


This document describes version 0.053 of Data::Sah::CoerceCommon (from Perl distribution Data-Sah-Coerce), released on 2022-09-22.




 get_coerce_rules(%args) -> [$status_code, $reason, $payload, \%result_meta]

Get coerce rules.

This routine determines coerce rule modules to use (based on the default set and coerce_rules specified), loads them, filters out modules with old/incompatible metadata version, and return the list of rules.

This common routine is used by Data::Sah compilers, as well as Data::Sah::Coerce and Data::Sah::CoerceJS.

This function is not exported.

Arguments ('*' denotes required arguments):

  • coerce_rules => array[str]

    A specification of coercion rules to use (or avoid).

    This setting is used to specify which coercion rules to use (or avoid) in a flexible way. Each element is a string, in the form of either NAME to mean specifically include a rule, or !NAME to exclude a rule.

    Some coercion modules are used by default, unless explicitly avoided using the '!NAME' rule.

    To not use any rules:

    To use the default rules plus R1 and R2:

     ['R1', 'R2']

    To use the default rules but not R1 and R2:

     ['!R1', '!R2']
  • coerce_to => str

    Some Sah types, like date, can be represented in a choice of types in the target language. For example, in Perl you can store it as a floating number a.k.a. float(epoch), or as a DateTime object, or Time::Moment object. Storing in DateTime can be convenient for date manipulation but requires an overhead of loading the module and storing in a bulky format. The choice is yours to make, via this setting.

  • compiler* => str

  • data_term* => str

  • type* => sah::type_name

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)



If set to false, will not support old prefix (Data::Sah::Coerce::<$TARGET_TYPE>::<$SOURCE_TYPE_AND_DESC>. Mainly for testing.


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