@spec extract_atom(data(), String.t(), %{required(any()) => atom()}, atom()) ::
  nil | atom()

Returns value of field_name as an atom.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)
• mapping is a map of "value" => :atom used to find which atom correspond to the field's value

Returns default on failure (field empty, no mapping...)

@spec extract_binary(data(), String.t(), nil | String.t()) :: nil | String.t()

Returns value of field_name as a binary.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a string...)

@spec extract_boolean(data(), String.t(), nil | boolean()) :: nil | boolean()

Returns value of field_name as a boolean.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a boolean...)

@spec extract_custom(data(), String.t(), (any() -> any())) :: any()

Returns value of field_name processed by fun.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)
• fun is a function of arity 1

Returns nil if the field is not included in the payload.

@spec extract_date(data(), String.t(), nil | Date.t()) :: nil | Date.t()

Returns value of field_name as a Date.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, invalid format, invalid date...)

@spec extract_datetime(data(), String.t(), nil | DateTime.t()) :: nil | DateTime.t()

Returns value of field_name as a DateTime.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, invalid format, invalid datetime...)

@spec extract_link(data(), String.t(), nil | CFSync.Link.t()) :: nil | CFSync.Link.t()

Returns value of field_name as a CFSync.Link.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a link...)

@spec extract_links(data(), String.t(), nil | [CFSync.Link.t()]) ::
  nil | [CFSync.Link.t()]

Returns value of field_name as a list of CFSync.Link.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a list...)

@spec extract_list(data(), String.t(), nil | list()) :: nil | list()

Returns value of field_name as a list.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a list...)

@spec extract_map(data(), String.t(), nil | map()) :: nil | map()

Returns value of field_name as a map.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a map...)

@spec extract_number(data(), String.t(), nil | number()) :: nil | number()

Returns value of field_name as a number.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Be careful with the result as it can be either an integer or float, depending of it's value. A contentful decimal value of 1.0 will be stored as 1 in the JSON and read as an integer by JASON.

Returns default on failure (field empty, not a number...)

@spec extract_rich_text(data(), String.t(), nil | CFSync.RichText.t()) ::
  nil | CFSync.RichText.t()

Returns value of field_name as CFSync.RichText tree.

• data is the entry's payload as provided to CFSync.Entry.Fields.new/1
• field_name is the field's id in Contentful (ie. What is configured in Contentful app)

Returns default on failure (field empty, not a richtext...)