API reference

While Snimpy is targeted at being used interactively or through simple scripts, you can also use it from your Python program.

It provides a high-level interface as well as lower-level ones. However, the effort is only put in th manager module and other modules are considered as internal details.

manager module

This module is the high-level interface to Snimpy. It exposes Manager class to instantiate a new manager (which is an SNMP client). This is the preferred interface for Snimpy.

Here is a simple example of use of this module:

>>> load("IF-MIB")
>>> m = Manager("localhost")
>>> m.ifDescr[1]
<String: lo>
class snimpy.manager.Manager(host='localhost', community='public', version=2, cache=False, none=False, timeout=None, retries=None, loose=False, bulk=40, secname=None, authprotocol=None, authpassword=None, privprotocol=None, privpassword=None, contextname=None)[source]

SNMP manager. An instance of this class will represent an SNMP manager (client).

When a MIB is loaded with load(), scalars and row names from it will be made available as an instance attribute. For a scalar, reading the corresponding attribute will get its value while setting it will allow to modify it:

>>> load("SNMPv2-MIB")
>>> m = Manager("localhost", "private")
>>> m.sysContact
<String: root>
>>> m.sysContact = "Brian Jones"
>>> m.sysContact
<String: Brian Jones>

For a row name, the provided interface is like a Python dictionary. Requesting an item using its index will retrieve the value from the agent (the server):

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> m.ifDescr[1]
<String: lo>
>>> m.ifName[1] = "Loopback interface"

Also, it is possible to iterate on a row name to get all available values for index:

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> for idx in m.ifDescr:
...     print(m.ifDescr[idx])

You can get a slice of index values from a table by iterating on a row name subscripted by a partial index:

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> for idx in m.ipNetToMediaPhysAddress[1]:
...     print(idx)
(<Integer: 1>, <IpAddress: 127.0.0.1>)

You can use multivalue indexes in two ways: using Pythonic multi-dimensional dict syntax, or by providing a tuple containing index values:

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> m.ipNetToMediaPhysAddress[1]['127.0.0.1']
<String: aa:bb:cc:dd:ee:ff>
>>> m.ipNetToMediaPhysAddress[1, '127.0.0.1']
<String: aa:bb:cc:dd:ee:ff>

A context manager is also provided. Any modification issued inside the context will be delayed until the end of the context and then grouped into a single SNMP PDU to be executed atomically:

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> with m:
...     m.ifName[1] = "Loopback interface"
...     m.ifName[2] = "First interface"

Any error will be turned into an exception:

>>> load("IF-MIB")
>>> m = Manager("localhost", "private")
>>> m.ifDescr[999]
Traceback (most recent call last):
    ...
SNMPNoSuchName: There is no such variable name in this MIB.
snimpy.manager.load(mibname)[source]

Load a MIB in memory.

Parameters

mibname (str) – MIB name or filename

Internal modules

Those modules shouldn’t be used directly.

mib module

This module is a low-level interface to manipulate and extract information from MIB files. It is a CFFI wrapper around libsmi. You may find convenient to use it in other projects but the wrapper is merely here to serve Snimpy use and is therefore incomplete.

class snimpy.mib.Column(node)[source]

MIB column node. This class represent a column of a table.

property table

Get table associated with this column.

Returns

The Table instance associated to this column.

class snimpy.mib.Node(node)[source]

MIB node. An instance of this class represents a MIB node. It can be specialized by other classes, like Scalar, Table, Column, Node.

property enum

Get possible enum values. When the node can only take a discrete number of values, those values are defined in the MIB and can be retrieved through this property.

Returns

The dictionary of possible values keyed by the integer value.

property fmt

Get node format. The node format is a string to use to display a user-friendly version of the node. This is can be used for both octet strings or integers (to make them appear as decimal numbers).

Returns

The node format as a string or None if there is no format available.

property oid

Get OID for the current node. The OID can then be used to request the node from an SNMP agent.

Returns

OID as a tuple

property ranges

Get node ranges. An node can be restricted by a set of ranges. For example, an integer can only be provided between two values. For strings, the restriction is on the length of the string.

The returned value can be None if no restriction on range exists for the current node, a single value if the range is fixed or a list of tuples or fixed values otherwise.

Returns

The valid range for this node.

property type

Get the basic type associated with this node.

Returns

The class from basictypes module which can represent the node. When retrieving a valid value for this node, the returned class can be instanciated to get an appropriate representation.

property typeName

Retrieves the name of the the node’s current declared type (not basic type).

Returns

A string representing the current declared type, suitable for assignment to type.setter.

class snimpy.mib.Notification(node)[source]

MIB notification node. This class represent a notification.

property objects

Get objects for a notification.

Returns

The list of objects (as Column, Node or Scalar instances) of the notification.

exception snimpy.mib.SMIException[source]

SMI related exception. Any exception thrown in this module is inherited from this one.

class snimpy.mib.Scalar(node)[source]

MIB scalar node. This class represents a scalar value in the MIB. A scalar value is a value not contained in a table.

class snimpy.mib.Table(node)[source]

MIB table node. This class represents a table. A table is an ordered collection of objects consisting of zero or more rows. Each object in the table is identified using an index. An index can be a single value or a list of values.

property columns

Get table columns. The columns are the different kind of objects that can be retrieved in a table.

Returns

list of table columns (Column instances)

property implied

Is the last index implied? An implied index is an index whose size is not fixed but who is not prefixed by its size because this is the last index of a table.

Returns

True if and only if the last index is implied.

property index

Get indexes for a table. The indexes are used to locate a precise row in a table. They are a subset of the table columns.

Returns

The list of indexes (as Column instances) of the table.

snimpy.mib.get(mib, name)[source]

Get a node by its name.

Parameters
  • mib – The MIB name to query

  • name – The object name to get from the MIB

Returns

the requested MIB node (Node)

snimpy.mib.getByOid(oid)[source]

Get a node by its OID.

Parameters

oid – The OID as a tuple

Returns

The requested MIB node (Node)

snimpy.mib.getColumns(mib)[source]

Return all columns from a givem MIB.

Parameters

mib – The MIB name

Returns

The list of all columns for the MIB

Return type

list of Column instances

snimpy.mib.getNodes(mib)[source]

Return all nodes from a given MIB.

Parameters

mib – The MIB name

Returns

The list of all MIB nodes for the MIB

Return type

list of Node instances

snimpy.mib.getNotifications(mib)[source]

Return all notifications from a givem MIB.

Parameters

mib – The MIB name

Returns

The list of all notifications for the MIB

Return type

list of Notification instances

snimpy.mib.getScalars(mib)[source]

Return all scalars from a given MIB.

Parameters

mib – The MIB name

Returns

The list of all scalars for the MIB

Return type

list of Scalar instances

snimpy.mib.getTables(mib)[source]

Return all tables from a given MIB.

Parameters

mib – The MIB name

Returns

The list of all tables for the MIB

Return type

list of Table instances

snimpy.mib.load(mib)[source]

Load a MIB into the library.

Parameters

mib – The MIB to load, either a filename or a MIB name.

Returns

The MIB name that has been loaded.

Raises

SMIException – The requested MIB cannot be loaded.

snimpy.mib.loadedMibNames()[source]

Generates the list of loaded MIB names.

Yield

The names of all currently loaded MIBs.

snimpy.mib.path(path=None)[source]

Set or get a search path to libsmi.

When no path is provided, return the current path, unmodified. Otherwise, set the path to the specified value.

Parameters

path – The string to be used to change the search path or None

snimpy.mib.reset()[source]

Reset libsmi to its initial state.

snmp module

This module is a low-level interface to build SNMP requests, send them and receive answers. It is built on top of pysnmp but the exposed interface is far simpler. It is also far less complete and there is an important dependency to the basictypes module for type coercing.

exception snimpy.snmp.SNMPAuthorization
exception snimpy.snmp.SNMPBadValue[source]
exception snimpy.snmp.SNMPCommitFailed
exception snimpy.snmp.SNMPEndOfMibView
exception snimpy.snmp.SNMPException[source]

SNMP related base exception. All SNMP exceptions are inherited from this one. The inherited exceptions are named after the name of the corresponding SNMP error.

exception snimpy.snmp.SNMPGen
exception snimpy.snmp.SNMPInconsistentName
exception snimpy.snmp.SNMPInconsistentValue
exception snimpy.snmp.SNMPNoAccess
exception snimpy.snmp.SNMPNoCreation
exception snimpy.snmp.SNMPNoSuchInstance
exception snimpy.snmp.SNMPNoSuchName[source]
exception snimpy.snmp.SNMPNoSuchObject
exception snimpy.snmp.SNMPNotWritable
exception snimpy.snmp.SNMPReadOnly[source]
exception snimpy.snmp.SNMPResourceUnavailable
exception snimpy.snmp.SNMPTooBig[source]
exception snimpy.snmp.SNMPUndoFailed
exception snimpy.snmp.SNMPWrongEncoding
exception snimpy.snmp.SNMPWrongLength
exception snimpy.snmp.SNMPWrongType
exception snimpy.snmp.SNMPWrongValue
class snimpy.snmp.Session(host, community='public', version=2, secname=None, authprotocol=None, authpassword=None, privprotocol=None, privpassword=None, contextname=None, bulk=40, none=False)[source]

SNMP session. An instance of this object will represent an SNMP session. From such an instance, one can get information from the associated agent.

property bulk

Get bulk settings.

Returns

False if bulk is disabled or a non-negative integer for the number of repetitions.

get(*oids)[source]

Retrieve an OID value using GET.

Parameters

oids – a list of OID to retrieve. An OID is a tuple.

Returns

a list of tuples with the retrieved OID and the raw value.

property retries

Get number of times a request is retried.

Returns

Number of retries for each request.

set(*args)[source]

Set an OID value using SET. This function takes an odd number of arguments. They are working by pair. The first member is an OID and the second one is basictypes.Type instace whose pack() method will be used to transform into the appropriate form.

Returns

a list of tuples with the retrieved OID and the raw value.

property timeout

Get timeout value for the current session.

Returns

Timeout value in microseconds.

walk(*oids)[source]

Walk from given OIDs but don’t return any “extra” results. Only results in the subtree will be returned.

Parameters

oid – OIDs used as a start point

Returns

a list of tuples with the retrieved OID and the raw value.

walkmore(*oids)[source]

Retrieve OIDs values using GETBULK or GETNEXT. The method is called “walk” but this is either a GETBULK or a GETNEXT. The later is only used for SNMPv1 or if bulk has been disabled using bulk() property.

Parameters

oids – a list of OID to retrieve. An OID is a tuple.

Returns

a list of tuples with the retrieved OID and the raw value.

basictypes module

This module is aimed at providing Pythonic representation of various SNMP types. Each SMIv2 type is mapped to a corresponding class which tries to mimic a basic type from Python. For example, display strings are like Python string while SMIv2 integers are just like Python integers. This module is some kind of a hack and its use outside of Snimpy seems convoluted.

class snimpy.basictypes.Bits(entity, value, raw=True)[source]

Class for bits.

pack()[source]

Prepare the instance to be sent on the wire.

class snimpy.basictypes.Boolean(entity, value, raw=True)[source]

Class for a boolean.

class snimpy.basictypes.Enum(entity, value, raw=True)[source]

Class for an enumeration. An enumaration is an integer but labels are attached to some values for a more user-friendly display.

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

class snimpy.basictypes.Integer(entity, value, raw=True)[source]

Class for any integer.

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.IpAddress(entity, value, raw=True)[source]

Class representing an IP address/

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.OctetString(entity, value, raw=True)[source]

Class for a generic octet string. This class should be compared to String which is used to represent a display string. This class is usually used to store raw bytes, like a bitmask of VLANs.

class snimpy.basictypes.Oid(entity, value, raw=True)[source]

Class to represent and OID.

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.String(entity, value, raw=True)[source]

Class for a display string. Such a string is an unicode string and it is therefore expected that only printable characters are used. This is usually the case if the corresponding MIB node comes with a format string.

With such an instance, the user is expected to be able to provide a formatted. For example, a MAC address could be written 00:11:22:33:44:55.

class snimpy.basictypes.StringOrOctetString(entity, value, raw=True)[source]
classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.Timeticks(entity, value, raw=True)[source]

Class for timeticks.

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.Type(entity, value, raw=True)[source]

Base class for all types.

classmethod fromOid(entity, oid, implied=False)[source]

Create instance from an OID.

This is the sister function of toOid().

Parameters
  • oid – The OID to use to create an instance

  • entity – The MIB entity we want to instantiate

Returns

A couple (l, v) with l the number of suboids needed to create the instance and v the instance created from the OID

pack()[source]

Prepare the instance to be sent on the wire.

toOid(implied=False)[source]

Convert to an OID.

If this function is implemented, then class function fromOid() should also be implemented as the “invert” function of this one.

This function only works if the entity is used as an index! Otherwise, it should raises NotImplementedError.

Returns

An OID that can be used as index

class snimpy.basictypes.Unsigned32(entity, value, raw=True)[source]

Class to represent an unsigned 32bits integer.

pack()[source]

Prepare the instance to be sent on the wire.

class snimpy.basictypes.Unsigned64(entity, value, raw=True)[source]

Class to represent an unsigned 64bits integer.

pack()[source]

Prepare the instance to be sent on the wire.

snimpy.basictypes.build(mibname, node, value)[source]

Build a new basic type with the given value.

Parameters
  • mibname – The MIB to use to locate the entity.

  • node – The node that will be attached to this type.

  • value – The initial value to set for the type.

Returns

A Type instance