# Available Policy Workflow Blocks Starting with the [Wikipedia definition](https://en.wikipedia.org/wiki/Workflow_engine), a Policy Workflow Engine (PWE) is a software application that manages business processes based on business rules and business data which are defined within the context of a specific policy. A PWE, therefore, manages and monitors the state of required policy actions and the required information flow in a policy grouped into a policy workflow, and determines which are the next policy actions based on the state of a policy workflow. The policy actions may be anything from saving an application form in a document management system to sending a reminder e-mail to users or escalating overdue items to management. Policy Workflow Blocks enable different business logic to exist within the Guardian’s PWE. ### Available Policy Workflows Blocks

Block	Definition	Documentation Link
InterfaceContainerBlock	A block which contains and organizes other blocks.	InterfaceContainerBlock
PolicyRolesBlock	A block which determines a role for the user.	PolicyRolesBlock
InterfaceStepBlock	Similar to the InterfaceContainerBlock, with the difference that it can only render a single child element.	InterfaceStepBlock
requestVCDocumentBlock	A type of the block which creates a form from the schema, and sends the document to the server.	requestVCDocumentBlock
sendToGuardianBlock	A type of the block which can save a new or updated document.	sendToGuardianBlock
reassigningBlock	A type of block which re-signs the document and change the user to document owner.	reassigningBlock
InformationBlock	A block type which can display a notification or a progress bar.	InformationBlock
InterfaceDocumentsSourceBlock	A block type which outputs information from the DB as grid.	InterfaceDocumentsSourceBlock
paginationAddon	A block type which adds pagination to the InterfaceDocumentSourceBlock if added	paginationAddon
DocumentsSourceAddOn	A type of block for searching VC as grid	DocumentsSourceAddOn
filtersAddOn	A child block for 'DocumentsSourceAddon'. Contains additional dynamic filters	filtersAddOn
InterfaceActionBlock	A block to create custom actions.	InterfaceActionBlock
externalDataBlock	Receives data from the external source and passes them over the the next block.	externalDataBlock
retirementDocumentBlock	Receives the VC from the previous block and retires based on the rule(s).	retirementDocumentBlock
calculateContainerBlock & calculateMathAddonBlock	The blocks to calculate. calculateContainerBlock: Receives VC from the previous block. Passes the new VC to the next block. calculateMathOnBlock: Child block for 'calculateContainerBlock'. Contains descriptions of variables and formulas.	calculateContainerBlock & calculateMathAddonBlock
reportBlock	The block container for TrustChain.	reportBlock & reportItemBlock
reportItemBlock	The block for setting up the elements of the TrustChain.	reportBlock & reportItemBlock
Switch Block	This block transfers execution to one or more blocks depending on the parameters	switchBlock
timerBlock	timer object which triggers the event	TimerBlock
aggregateDocumentBlock	block responsible for aggregation of the documents	aggregateDocumentBlock
revocationBlock	This Block finds related messages in policy topics, and revokes those messages and sends it to Hedera topic, but it doesn’t save documents in DB	revocationBlock
setRelationshipsBlock	Contains DocumentSourceAddOn Block and set relationships for input document.	setRelationshipBlock
buttonBlock	Block responsible for creating buttons	buttonBlock
documentValidatorBlock	Block to validate documents, including linked documents	documentValidatorBlock
tokenActionBlock	Block is responsible to automation actions related to tokens	tokenActionBlock
tokenConfirmationBlock	Block enables the owner of the private key for the account to manually perform operations with the token	tokenConfirmationBlock
mintDocumentBlock	Block is responsible for adding configurations on calculating the amount of tokens to be minted.	mintDocumentBlock
groupManagerBlock	Block allows to manage group membership, add and remove users from the group.	groupManagerBlock
multiSignBlock	This block provides a way to specify multiple signators for a single VC document, and then create a VP based on it.	multiSignBlock
customLogicBlock	This block is used to perform Logic	customLogicBlock
splitBlock	This block allows to accumulate VC documents and produce new VCs in fixed chunks	splitBlock
wipeDocumentBlock	This block is used to wipe the Token	wipeDocumentBlock
CreateTokenBlock	This block is used to create Token template	CreateTokenBlock
impactAddon	This is an addon to create token impacts	impactAddon
Http Request Block	This block is used to retrieve outside data	HttpRequestBlock
historyAddon	This block turn on history on interfaceDocumentsSourceBlock.	historyAddon
selectiveAttributes Block	This block will filter attributes (option field) in documents returned by documentsSourceAddon.	selectiveAttributesBlock
tagsManagerBlock	This block is responsible for managing tags in policies.	tagsManagerBlock
externalTopicBlock	This block allows to configure the link to Hedera topics established by other policy instances for monitoring of ‘document published’ messages and ingestion of the targeted VC documents.	externalTopicBlock
messagesReportBlock	This block allows to create report based on the inter-referenced messages.	messagesReportBlock
notificationBlock	This block is used to generate notifications	notificationBlock
extractDataBlock	This block extractDataBlock provides means to extract a data set which corresponds to any of these embedded schemas (at any depth level)	extractDataBlock
button block Addon	This block is used to display interactive buttons	buttonBlockAddon
Dropdown Block Addon	The block is to display an interactive dropdown menu	dropdownBlockAddon
RequestVC Document Block Addon	This block is to display an interactive button in the interfaceDocumentsSourceBlock.	requestVcDocumentBlockAddon
Data Transformation Addon	This block is to produce a transformed result based on the data from the source and filters blocks	Data Transformation Addon
IntegrationButtonBlock	This block enable interaction with third-party data providers	IntegrationButton
Global Events Reader Block	This block subscribes to global topics and routes incoming events into policy branches	Global Events Reader Block
Global Events Writer Block	This block publishes document references to one or more global Hedera topics	Global Events Writer Block
mathBlock	This block defines calculations on document data in mathematical notation	MathBlock