Reading Ledger State with the Walley Python SDK

w.ledger reads the Canton ledger through Walley’s authenticated proxy — the Python twin of the dApp SDK’s ledgerApi. Common reads are named methods so you don’t need to know ledger endpoints; a raw passthrough covers everything else. The SDK’s bearer token is attached automatically.

Active contracts

The read you’ll reach for most, typically to feed contract ids into your dApp’s commands:

for c in w.ledger.active_contracts():
    print(c.contract_id, c.template_id, c.payload)

Filter by template — both id forms work, the package-id form and the package-name form:

w.ledger.active_contracts(
    template_ids=["#splice-amulet:Splice.AmuletRules:TransferPreapproval"])

w.ledger.active_contracts(
    template_ids=["6c5802f8...:Splice.AmuletRules:TransferPreapproval"])

Each ActiveContract lifts the useful fields out of the ledger’s nesting:

c.contract_id      # feed into your dApp's exercise commands
c.template_id      # <package-id>:Module:Entity
c.payload          # the contract's create arguments (dict)
c.created_event    # the raw ledger createdEvent, for anything else

By default the query runs as the client’s party at the current ledger end; override with party_id=, at_offset=, or verbose=True.

Raw passthrough

For anything the named methods don’t cover, forward requests directly — the path is the JSON Ledger API resource:

w.ledger.get("/v2/users")
w.ledger.post("/v2/updates/flats", json={...})
w.ledger.request("GET", "/v2/state/ledger-end")

The proxy is for reads, all submissions go through w.transactions. See Transactions & Fees.

Overview

Typescript SDK (dApp)

Python SDK

gRPC API

Reading Ledger State with the Walley Python SDK

Active contracts

Other named reads

Raw passthrough

​Active contracts

​Other named reads

​Raw passthrough

Active contracts

Other named reads

Raw passthrough