56 lines
1.7 KiB
Nim
56 lines
1.7 KiB
Nim
# nimbus-eth1
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# Copyright (c) 2021 Status Research & Development GmbH
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# Licensed under either of
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# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
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# http://www.apache.org/licenses/LICENSE-2.0)
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# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
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# http://opensource.org/licenses/MIT)
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# at your option. This file may not be copied, modified, or distributed
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# except according to those terms.
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## Read vertex recorfd on the layered Aristo DB delta architecture
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## ===============================================================
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{.push raises: [].}
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import
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std/tables,
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stew/results,
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"."/[aristo_desc, aristo_error]
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# ------------------------------------------------------------------------------
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# Public functions
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# ------------------------------------------------------------------------------
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proc getVtxCascaded*(
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db: AristoDbRef;
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vid: VertexID;
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): Result[VertexRef,AristoError] =
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## Cascaded lookup for data record down the transaction cascade.
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db.sTab.withValue(vid, vtxPtr):
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return ok vtxPtr[]
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# Down the rabbit hole of transaction layers
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var lDb = db
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while lDb.cascaded:
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lDb = lDb.stack
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lDb.sTab.withValue(vid, vtxPtr):
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return ok vtxPtr[]
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let be = lDb.backend
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if not be.isNil:
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return be.getVtxFn vid
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err(GetVtxNotFound)
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proc getVtx*(db: AristoDbRef; vid: VertexID): VertexRef =
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## Variant of `getVtxCascaded()` with returning `nil` on error ignoring the
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## error type information.
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let rc = db.getVtxCascaded vid
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if rc.isOk:
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return rc.value
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# ------------------------------------------------------------------------------
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# End
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# ------------------------------------------------------------------------------
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