Enum GetResult 

pub enum GetResult {
    Value(Value),
    NoSuchObject,
    NoSuchInstance,
}

Result of a GET operation on a specific OID.

This enum distinguishes between the RFC 3416-mandated exception types:

• Value: The OID exists and has the given value
• NoSuchObject: The OID’s object type is not supported (agent doesn’t implement this MIB)
• NoSuchInstance: The object type exists but this specific instance doesn’t (e.g., table row doesn’t exist)

For SNMPv1, both exception types result in a noSuchName error response. For SNMPv2c/v3, they result in the appropriate exception value in the response.

Example

use async_snmp::handler::{MibHandler, RequestContext, GetResult, GetNextResult, BoxFuture};
use async_snmp::{Oid, Value, VarBind, oid};

struct IfTableHandler {
    // Simulates interface table with indices 1 and 2
    interfaces: Vec<u32>,
}

impl MibHandler for IfTableHandler {
    fn get<'a>(&'a self, _ctx: &'a RequestContext, oid: &'a Oid) -> BoxFuture<'a, GetResult> {
        Box::pin(async move {
            let if_descr_prefix = oid!(1, 3, 6, 1, 2, 1, 2, 2, 1, 2);

            if oid.starts_with(&if_descr_prefix) {
                // Extract index from OID
                if let Some(&index) = oid.arcs().get(if_descr_prefix.len()) {
                    if self.interfaces.contains(&index) {
                        return GetResult::Value(Value::OctetString(
                            format!("eth{}", index - 1).into()
                        ));
                    }
                    // Index exists in MIB but not in our table
                    return GetResult::NoSuchInstance;
                }
            }
            // OID is not in our MIB at all
            GetResult::NoSuchObject
        })
    }

    fn get_next<'a>(&'a self, _ctx: &'a RequestContext, _oid: &'a Oid) -> BoxFuture<'a, GetNextResult> {
        Box::pin(async move { GetNextResult::EndOfMibView }) // Simplified
    }
}

Variants

Value(Value)

The OID exists and has this value.

NoSuchObject

The object type is not implemented by this agent.

Use this when the OID prefix (object type) is not recognized.

NoSuchInstance

The object type exists but this specific instance doesn’t.

Use this when the OID prefix is valid but the instance identifier (e.g., table index) doesn’t exist.

Implementations

impl GetResult

pub fn from_option(value: Option<Value>) -> Self

Create a GetResult from an Option<Value>.

This is a convenience method for migrating from the previous Option<Value> interface. None is treated as NoSuchObject.

Trait Implementations

impl Clone for GetResult

fn clone(&self) -> GetResult

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GetResult

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Option<Value>> for GetResult

fn from(value: Option<Value>) -> Self

Converts to this type from the input type.

impl From<Value> for GetResult

fn from(value: Value) -> Self

Converts to this type from the input type.

impl PartialEq for GetResult

fn eq(&self, other: &GetResult) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for GetResult