Accept ECS TLR, store it, search for Data tenants available, search for an item available for fulfillment (Сrawl phase)

Create a new backend Spring-based module mod-tlr

Create a new repo, and add it to building/deployment pipelines

Note: this is the 1st Spring-based module for the team

5

Create a database schema for storing ECS TLR requests

• to store ECS TLRs (entity describing the initial information about the request - instanceId, date-time, info from mod-search, tenant IDs it works with, …)

• to be able to track statuses

• to track ECS TLR and one-to-many relations to single-tenant TLRs

• Need to design data schema(-s) - this will appear along with WBS

• Need to design a set of ECS TLR statuses

• Liquibase

5

Add API endpoints for TLR mgmt and CRUD support

• create ECS TLR request

• read ECS TLR request by ID

• update ECS TLR request by ID

5-10 (it depends on if this can be implemented in a Spring-based module)

Implement a timer for triggering internal actions

3-5

Implement a call from mod-tlr to mod-search to retrieve a list of tenants by instanceId

• This will be triggered by a timer based on the ECS TLR request status

• need to create a mod-search repository

• https://wiki.folio.org/pages/viewpage.action?pageId=118269434

• Need to review mod-search API; assumption: no work in mod-search is required in this scenario

3-5

Implement logic for analyzing data from the mod-search and choosing which tenant to place the Single tenant TLR request to

• This is where we can start with the simplified logic first and postpone a more sophisticated approach to the Walk phase. E.g., the proposed option may look like this: get a list of tenants and information about how many items are in each of them. If there is only one tenant on the list, we work with him. If there are several tenants in the list, we select the one with the most items (this increases the likelihood of finding an item) and work with it

• Update ECS TLR with a chosen tenantId

• Need to design 1-to-many relation between ECS TLR and single-tenant TRL

3-5

Implement a call from the Central tenant’s mod-tlr to the Data tenant’s mod-circulation

• Assumption: the TLR-support feature flag is enabled in the Data tenant’s mod-circulation

• We can use one of the two following API endpoints - the one used for the Front-end (exact TLR request type needs to be specified), or the other used for requests from discovery (TLR request type can be defined as a result of Page/Recall/Hold selection). The second one is more appropriate for the Crawl phase though we would need to implement something else in the Walk phase. The option with sequential selection Page/Recall/Hold is very good for the first phase. Subsequently, the following logic can be implemented: make a Page request to each tenant (one by one) and check whether the item can be taken right now. If it fails, try a Recall request to each tenant and wait until you succeed. If it fails, make a Hold without an expiration date and wait until the item appears somewhere.

• Since there is an explicit requirement that non-fulfilled Congressional Loan requests remain open in perpetuity, the expiration period must be set without restrictions or have some significant value (this will be clarified later, in the process of more detailed analysis).

• In a regular single-tenant installation, when creating a TLR request, you can specify its type. In this case, a list of possible types and associated service points is formed on the back-end by searching through all known items and checking the circulation rules for them. In the case of ECS TLR, information about items and rules may not be available at the time the request is created. So the Page/Recall/Hold sequence seems justified in this case.

• What pick-up service point should be specified and used for TLR requests? (pre-defined? or one from the list of all available service points?) The requester should specify a pickup service point however the Data tenant can be not aware about it so it’s required to mock it somehow (note: mod-dcb does the same as a part of DCB transaction)

• How to specify circulation rules for such a request? Can we assume that the circulation rules are the same for the whole LoC? Using the Data tenants' circulation rules is the most straightforward option (this is how it will work if we do nothing)

3-5 to make an API call

+ 3-5 to address questions with service points and circulation rules

Add Kafka integration

• For Page/Recall types of TLR we will have the item ID immediately in the response, so won’t need to wait

• For Hold we would need to listen to a Kafka topic for events related to single-tenant TLR request status changes - it should change to OPEN In transit

5-10 ( need to implement event publishing in mod-circulation and consumers/listeners in mod-tlr)

Transaction initialization in mod-dcb

• 2 calls from mod-tlr to mod-dcb in Central Tenant and Data Tenant to create a DCB transaction

• https://s3.amazonaws.com/foliodocs/api/edge-dcb/s/edge-dcb.html#tag/circulation/operation/createDCBTransaction

3-5

Update mod-dcb

• mod-dcb must learn to accept an optional TLR ID parameter in the Create DCB transaction request as part of the item object https://s3.amazonaws.com/foliodocs/api/edge-dcb/s/edge-dcb.html and then pass it further to mod-circulation when creating an item request (add an if statement, add/update tests)

3

Update mod-circulation

• when creating a request for an item, mod-circulation needs to learn to accept an optional parameter with a TLR ID, and if it is present, learn to find the corresponding TLR and use it instead of creating a new request

• review the process of communication between mod-dcb and mod-circulation

?

mod-tlr - Orchestration phase

• 2 API calls - getDCBTransactionStatusById and updateDCBTransactionStatus

• Need to store the most recent statuses to be able to compare them with information from getDCBTransactionStatusById

• https://wiki.folio.org/display/FOLIJET/DCB+Integration

3-5

ui-requests

Since we need to be able to place an ECS TLR request directly through UI, ui-requests need to be able to support this

• new setting

• call to mod-circulation (for Data Tenant) or to mod-tlr (for Central Tenant)