Read Data

This handler (com.rierino.handler.ReadEventHandler) provides ability to select one, multiple or all records from a state manager on demand, facilitating common REST API read calls.

Handler Parameters

This handler requires no parameters. This handler is cacheable.

Actions

Get

Reads and returns aggregate for a single ID from a specific state manager. Event metadata fields applicable for this action are as follows:

Field	Definition	Example	Default
domain	Name of the state manager to read data from	product	-
inputElement	Json path for the input in request event payload	parameters	-
outputElement	Json path for the output in response event payload	product	-

With event metadata parameters as:

Parameter	Definition	Example	Default
outputPattern	JMESPath pattern to apply on data output, before returning response	{id:id, name:data.name, description:data.description}	-
idPath	Json path for the id field in input element	product.id	id
idValue	Static ID to read instead of idPath value	1234	-
fields	Comma separated list of fields to keep in response	data.name,data.description	-
form	Form of response to produce (i.e. full=including custom data fields)	full	-
customizeBy	Comma separated list of customizations to apply to data	luxury,tech_savvy	-
versionType	Type of version data to return (history, snapshot, none)	history	none

Example

Input

{
    "parameters": {
        "id": "given-id"
    }
}

Event Metadata

GetList

Reads and returns aggregates for a list of ID from a specific state manager. Event metadata fields applicable for this action are as follows:

Field	Definition	Example	Default
domain	Name of the state manager to read data from	product	-
inputElement	Json path for the input in request event payload	parameters.products	-
outputElement	Json path for the output in response event payload	list	-

If input element ends with .*, it allows iteration of an array of {id:""} objects for injection of their details. Otherwise, this action expects a list of ids in [""] form.

With event metadata parameters as:

Parameter	Definition	Example	Default
outputPattern	JMESPath pattern to apply on each data output, before returning response	{id:id, name:data.name, description:data.description}	-
fields	Comma separated list of fields to keep in response	data.name,data.description	-
form	Form of response to produce (i.e. full=including custom data fields)	full	-
customizeBy	Comma separated list of customizations to apply to data	luxury,tech_savvy	-
skip	Number of rows to skip in results	20	-
limit	Maximum number of rows to return	10	-
versionType	Type of version data to return (history, snapshot, none)	history	none

For complex use cases with skip, limit, fields or outputPattern using QueryEventHandler could provide better performance, as it benefits from pass-thru query execution.

GetAll

Reads and returns all aggregates from a specific state manager. Event metadata fields applicable for this action are as follows:

Field	Definition	Example	Default
domain	Name of the state manager to read data from	product	-
outputElement	Json path for the output in response event payload	list	-

With event metadata parameters as:

Parameter	Definition	Example	Default
outputPattern	JMESPath pattern to apply on each data output, before returning response	{id:id, name:data.name, description:data.description}	-
fields	Comma separated list of fields to keep in response	data.name,data.description	-
form	Form of response to produce (i.e. full=including custom data fields)	full	-
customizeBy	Comma separated list of customizations to apply to data	luxury,tech_savvy	-
first	Whether only the first record should be returned as a single value or not	true	-
skip	Number of rows to skip in results	20	-
limit	Maximum number of rows to return	10	-
orderBy	Order by field for results with direction	name desc	-