Daily Logs for Aug 25, 2025

Tags: spring data canton blockchain walmart online

Written by: Tushar Sharma

Featured image for Daily Logs for Aug 25, 2025

Dear Vishi, dear logs for today.

Spring Data

Spring Data also added Reactive Streams support into the existing projects.

NoSQL support, such as Redis, MongoDB, Couchbase and Cassandra are the first-class citizen in the WebFlux world.

RDBMS support, such as JDBC and JPA are designated for blocking access will not work under the new WebFlux applications.

To resolve the problem, Spring team leads a new reactive specification R2dbc to access RDBMS. Similar to the JDBC specification, R2dbc provides a collection of standardized APIs and allow you to implement your own database drivers through r2dbc-spi. Currently, MySQL(and MariaDB), MSSQL, Oracle, H2, PostgresSQL have got support. Check the R2dbc website for more info.

To create your Repository , create an interface to extend ReactiveCrudRepository or ReactiveSortingRepository or a subproject specific Repository. For example:

            interface PostRepository extends ReactiveCrudRepository{}

interface PostRepository extends ReactiveSortingRepository{}

interface PostRepository extends ReactiveMongoRepository{}

Canton

Party ID is a logical identity in the Canton network, similar to a service account or a role in AWS IAM.

What Is a Validator Node? A validator node is essentially a container running in the network that helps upload and process DAML Archives (DARs). These DARs contain smart contracts written in DAML, which is a language for modeling business logic. Smart contracts are programs that live on the blockchain - in this case, Canton's ledger - and enforce rules automatically.

This is the prerequisite manual step before using ledger API for Canton to write to the blockchain.

Uploading DARs to a validator node is a prerequisite step before your applications can interact with the ledger via the Ledger API.

            +----------------+     1. Upload .dar     +---------------------+
| Daml Team /    | ---------------------> | Canton Validator Node |
| CI/CD Pipeline |      (daml deploy)     |                     |
|                |                        | → DAML logic loaded  |
|                |                        | → Rules enforced     |
+----------------+                        +----------+----------+
                                                    |
                                                    | Runs Ledger API
                                                    | (gRPC / JSON)
                                                    |
+----------------+     2. Use Ledger API             |
| Your App       | ----------------------------------+
| (Java/Rust)    |    (create contracts, query data)
+----------------+

          

Git SubModule

Submodule is nice feature to refer another repo inside your own repo. However it's tied to the commit. To sycn your changes

git submodule update --remote --merge

Online

Walmart

I saw this tweet from US Senator Mike Lee¹

Is it time to pause H1-B visas? https://x.com/wallstreetmav/status/1959973681037226195

This post was based on a news article publised by ctol.digital. I wanted to see how reputed this news organization is. On its contact page, it says

Your premier IT consultancy based in Switzerland 🇨🇭 for transformative tech solutions, unparalleled digital strategy excellence

This is their landing news page, now sure how much authentic it is 🤷

Harmeet Dhillon also tweeted this²

This is deeply concerning https://x.com/wallstreetmav/status/1959973681037226195

This was the response from Dan Bartlett, EVP of Corporate Affairs at Walmart. ³

To set the record straight, earlier this month, following an investigation, Walmart terminated one vendor and a small number of U.S.-based associates. This investigation had nothing to do with H-1B visas and everything to do with acting with Integrity, a core Walmart value.

It seems now that the original tweet is deleted.

Burning of the Flag

Trump has issued an executive order. Burning the flag is usually protected under the First Amendment as a form of political protest. However, the order directs federal authorities to prioritize enforcement of existing laws - such as those against property damage, disorderly conduct, hate crimes, or aiding and abetting - when flag desecration occurs in connection with these offenses. Additionally, foreign nationals who desecrate the flag may face immigration consequences, including visa denial, revocation, or removal.

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