mirror of https://github.com/waku-org/nwaku.git
100 lines
3.0 KiB
Nim
100 lines
3.0 KiB
Nim
{.push raises: [].}
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import
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std/[options, bitops, sequtils, net], stew/results, eth/keys, libp2p/crypto/crypto
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import ../common/enr
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const CapabilitiesEnrField* = "waku2"
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type
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## 8-bit flag field to indicate Waku node capabilities.
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## Only the 4 LSBs are currently defined according
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## to RFC31 (https://rfc.vac.dev/spec/31/).
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CapabilitiesBitfield* = distinct uint8
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## See: https://rfc.vac.dev/spec/31/#waku2-enr-key
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## each enum numbers maps to a bit (where 0 is the LSB)
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Capabilities* {.pure.} = enum
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Relay = 0
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Store = 1
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Filter = 2
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Lightpush = 3
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func init*(T: type CapabilitiesBitfield, lightpush, filter, store, relay: bool): T =
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## Creates an waku2 ENR flag bit field according to RFC 31 (https://rfc.vac.dev/spec/31/)
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var bitfield: uint8
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if relay:
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bitfield.setBit(0)
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if store:
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bitfield.setBit(1)
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if filter:
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bitfield.setBit(2)
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if lightpush:
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bitfield.setBit(3)
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CapabilitiesBitfield(bitfield)
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func init*(T: type CapabilitiesBitfield, caps: varargs[Capabilities]): T =
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## Creates an waku2 ENR flag bit field according to RFC 31 (https://rfc.vac.dev/spec/31/)
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var bitfield: uint8
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for cap in caps:
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bitfield.setBit(ord(cap))
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CapabilitiesBitfield(bitfield)
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converter toCapabilitiesBitfield*(field: uint8): CapabilitiesBitfield =
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CapabilitiesBitfield(field)
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proc supportsCapability*(bitfield: CapabilitiesBitfield, cap: Capabilities): bool =
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testBit(bitfield.uint8, ord(cap))
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func toCapabilities*(bitfield: CapabilitiesBitfield): seq[Capabilities] =
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toSeq(Capabilities.low .. Capabilities.high).filterIt(
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supportsCapability(bitfield, it)
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)
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# ENR builder extension
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proc withWakuCapabilities*(builder: var EnrBuilder, caps: CapabilitiesBitfield) =
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builder.addFieldPair(CapabilitiesEnrField, @[caps.uint8])
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proc withWakuCapabilities*(builder: var EnrBuilder, caps: varargs[Capabilities]) =
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withWakuCapabilities(builder, CapabilitiesBitfield.init(caps))
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proc withWakuCapabilities*(builder: var EnrBuilder, caps: openArray[Capabilities]) =
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withWakuCapabilities(builder, CapabilitiesBitfield.init(@caps))
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# ENR record accessors (e.g., Record, TypedRecord, etc.)
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func waku2*(record: TypedRecord): Option[CapabilitiesBitfield] =
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let field = record.tryGet(CapabilitiesEnrField, seq[uint8])
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if field.isNone():
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return none(CapabilitiesBitfield)
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if field.get().len != 1:
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return none(CapabilitiesBitfield)
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some(CapabilitiesBitfield(field.get()[0]))
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proc supportsCapability*(r: Record, cap: Capabilities): bool =
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let recordRes = r.toTyped()
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if recordRes.isErr():
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return false
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let bitfieldOpt = recordRes.value.waku2
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if bitfieldOpt.isNone():
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return false
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let bitfield = bitfieldOpt.get()
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bitfield.supportsCapability(cap)
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proc getCapabilities*(r: Record): seq[Capabilities] =
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let recordRes = r.toTyped()
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if recordRes.isErr():
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return @[]
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let bitfieldOpt = recordRes.value.waku2
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if bitfieldOpt.isNone():
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return @[]
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let bitfield = bitfieldOpt.get()
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bitfield.toCapabilities()
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