| Copyright | © Herbert Valerio Riedel 2015-2018 |
|---|---|
| License | GPL-2.0-or-later |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Data.YAML.Aeson
Contents
Description
The YAML 1.2 format provides
a much richer data-model and feature-set
than the JavaScript Object Notation (JSON) format.
However, sometimes it's desirable to ignore the extra capabilities
and treat YAML as if it was merely a more convenient markup format
for humans to write JSON data. To this end this module provides a
compatibility layer atop Data.YAML which allows decoding YAML
documents in the more limited JSON data-model while also providing
convenience by reusing aeson's FromJSON instances for decoding
the YAML data into native Haskell data types.
Synopsis
- decode1 :: FromJSON v => ByteString -> Either String v
- decode1' :: FromJSON v => SchemaResolver -> (Value -> Either String Text) -> ByteString -> Either String v
- decodeValue :: ByteString -> Either String [Value]
- decodeValue' :: SchemaResolver -> (Value -> Either String Text) -> ByteString -> Either String [Value]
- scalarToValue :: Scalar -> Maybe Value
Parsing YAML using JSON models
High-level parsing/decoding via FromJSON instances
decode1 :: FromJSON v => ByteString -> Either String v Source #
Parse a single YAML document using the coreSchemaResolver and decode to Haskell types using FromJSON instances.
This operation will fail if the YAML stream does not contain
exactly one YAML document. This operation is designed to be the
moral equivalent of aeson's eitherDecode function.
See decodeValue for more information about this functions' YAML
decoder configuration.
decode1' :: FromJSON v => SchemaResolver -> (Value -> Either String Text) -> ByteString -> Either String v Source #
Variant of decode1 allowing for customization. See decodeValue' for documentation of parameters.
Parsing into JSON AST (Value)
decodeValue :: ByteString -> Either String [Value] Source #
Parse YAML documents into JSON Value ASTs
This is a wrapper function equivalent to
decodeValue'coreSchemaResolveridentityKeyConv
with identityKeyConv being defined as
> identityKeyConv :: Data.Aeson.Value -> Either String Text > identityKeyConv (Data.Aeson.String k) = Right k > identityKeyConv _ = Left "non-String key encountered in YAML mapping"
which performs no conversion and will fail when encountering YAML Scalars that have not been resolved to a text Scalar (according to the respective YAML schema resolver).
Arguments
| :: SchemaResolver | YAML Schema resolver to use |
| -> (Value -> Either String Text) | JSON object key conversion function. This operates on the YAML node as resolved by the |
| -> ByteString | YAML document to parse |
| -> Either String [Value] |
Parse YAML documents into JSON Value ASTs
YAML Anchors will be resolved and inlined accordingly. Resulting YAML cycles are not supported and will be treated as a decoding error.
NOTE: This decoder ignores YAML tags and relies on the YAML
SchemaResolver provided to ensure that scalars have been resolved
to the proper known core YAML types.