Module wasm_host_abi 

WASM Host Function ABI

This module defines the host functions that WASM plugins can call to interact with SochDB.

Design Principles

1. Capability-Checked: All operations verify permissions before execution
2. Memory-Safe: All data crosses the WASM boundary via explicit serialization
3. Low-Overhead: Designed for ~100ns per call overhead target
4. Auditable: Every host call is logged for security auditing

Available Host Functions

Function	Description	Capability Required
soch_read	Read rows from a table	can_read_table
soch_write	Write rows to a table	can_write_table
soch_delete	Delete rows from a table	can_write_table
vector_search	Similarity search	can_vector_search
index_lookup	Point/range index lookup	can_index_search
emit_metric	Emit observability metric	(always allowed)
log_message	Log a message	(always allowed)
get_config	Read plugin config	(always allowed)

Memory Model

┌─────────────────────────────────────────────────────┐
│                  WASM Linear Memory                  │
│  ┌─────────────────────────────────────────────┐    │
│  │         Plugin Code & Data                   │    │
│  └─────────────────────────────────────────────┘    │
│  ┌─────────────────────────────────────────────┐    │
│  │     Input Buffer (host writes here)         │    │
│  └─────────────────────────────────────────────┘    │
│  ┌─────────────────────────────────────────────┐    │
│  │     Output Buffer (plugin writes here)       │    │
│  └─────────────────────────────────────────────┘    │
└─────────────────────────────────────────────────────┘

Modules

wire

Serialization helpers for crossing WASM boundary

Structs

AuditEntry

Audit log entry

EmitMetric

Emit an observability metric

HostFunctionContext

Context passed to host function implementations

HostFunctionRegistry

Registry of available host functions

LogMessage

Log a message

SochRead

Read rows from a table

SochWrite

Write rows to a table

VectorSearch

Vector similarity search

Enums

HostCallResult

Result of a host function call

Traits

HostFunction

Trait for host function implementations