wiki:AaronHelsinger/GAPI_AM_API_DRAFT/MethodSignatures

Version 7 (modified by Aaron Helsinger, 8 years ago) (diff)

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GENI Aggregate Manager API Draft Revisions Method Signatures Summary

This page documents the DRAFT GENI Aggregate Manager API full method signatures, if all proposed revisions are adopted. This includes proposals that have already been adopted, and others still under discussion.

The current officially adopted version of the API is 2 and is documented on the main API page.

The current adopted or proposed changes for the AM API, whose impacts are reflected here, are documented on the AM API Draft wiki page.

Change summary - method signatures

If the generally agreed-upon change sets listed here are adopted, the final method signatures will be as follows:


API Overview

The GENI Aggregate Manager API is the control plane interface by which experimenters discover, reserve and control resources at resource providers. It does not include resource specific interactions, application level interactions, or monitoring and management functions.

API Protocols and Data Structures

GENI specifies that the AM API is provided via XML-RPC over an SSL connection. Aggregate Managers shall require client side GENI certificates to authenticate users, accepting only certificates that comply with the adopted GENI certificates standards. The GENI AM API therefore assumes that users have already been authenticated, and that the aggregate manager has available the client certificate to identify the user.

Clients are authorized to take actions at aggregates using GENI credentials. To that end, all methods that require authorization take an argument credentials. In particular, operations on a single GENI slice will require a credential (set) that authorizes the client whose certificate was used to authenticate to operate on the slice named by a urn argument to the method or on the slice containing the slivers named by a urns argument.

The primary data structure used within this API is a resource specification, known as an RSpec. These XML documents follow a specific set of schemas. They are used by aggregates to list and describe local resources (advertisement RSpecs), by experimenters to describe desired resources (request RSpecs), and then by aggregates to describe reserved resources (manifest RSpecs). For more information on RSpecs, see the details page.

Using the GENI AM API

Clients (experimenters) use the AM API to discover resources (!ListResources), request resources (Allocate), provision reserved resources (Provision), start resources (!PerformOperationalAction), check the status of resources as they are started (Status), extend their reservation (Renew), and then return the resources when done (Delete). Client tools may use `GetVersion` to ensure aggregates speak a compatible version of the AM API and known formats for RSpecs. Administrators may call Shutdown to stop the resources of a slice at this aggregate, perhaps if that slice is misbehaving.

!ListResources returns to the client an advertisement RSpec - a detailed listing of the resources available at that aggregate. From this information, the experimenter may determine which resources to reserve for their use. The RSpec should also have enough information to help the experimenter set the initial configuration for their resources.

Once the experimenter has selected the resources they want and how to configure them, they produce a request RSpec, detailing the resources they want and how they should be configured. They separately contact their slice authority to obtain a slice credential (or set of credentials), granting them rights to reserve resources for that slice. The experimenter then calls Allocate on this API, passing in both the slice credential and the request RSpec. The aggregate then attempts to satisfy the experimenter's resource request. If the aggregate can satisfy the request, the aggregate reserves the resources for the experimenter. The resources have not been provisioned yet, giving the experimenter a chance to verify the reservation, or check for corresponding resource availability in another aggregate. If it is acceptable, the experimenter calls Provision to set up the resources. The aggregate then starts the process of instantiating the resources and configuring them as requested in the request RSpec. Once that process has started, the Provision call returns with a manifest RSpec, listing the resources as reserved and initially configured for the experimenter.

The experimenter can then poll the aggregate manager to watch as the resources are configured and become ready for use, by calling Status. A given aggregate and sliver type may use a different set of states to indicate that provisioning is complete, and further operational actions are possible - see the AM's Ad RSpec. In many cases, this indication comes with a geni_operational_state value of geni_notready. Once the resources are ready for use, the experimenter will typically call !PerformOperationalAction(geni_start) to start the resources (e.g. boot a machine). The experimenter will also call Renew to request that their reservation lasts as long as they require the resources for. When the experimenter is done using the resources, they call Delete to end their reservation. The aggregate then stops and clears the resources, freeing them for use by other clients.

Typical client work flow:

  1. <Experimenter gets a GENI certificate and slice credential>
  2. GetVersion(): learn RSpec formats supported at this aggregate
  3. ListResources(<user credential>, options): get Ad RSpec describing available resources
  4. <Experimenter constructs a request RSpec>
  5. Allocate(<slice URN>, <slice credential>, <request RSpec>, {}):
    • Aggregate reserves resources
    • Return is a manifest RSpec describing the reserved resources
  6. Provision(<slice URN or sliver URNs>, <slice credential>, <request RSpec>, <users struct>, {}):
    • Aggregate instantiates resources
    • Return is a manifest RSpec describing the reserved resources, plus any instantiation-specific configuration information
  7. Status(<slice URN or sliver URNs>, <slice credential>, {}) to check that resources are provisioned (e.g. look for operational state geni_notready.
  8. PerformOperationalAction(<slice URN>, <slice credential>, geni_start, {}):
    • Aggregate starts resources
  9. Status(<slice URN or sliver URNs>, <slice credential>, {}) to check that resources have started
  10. Renew(<slice URN or sliver URNs>, <slice credential>, newtime, {}) to extend reservation
  11. <Experimenter uses resources>
  12. Delete(<slice URN or sliver URNs>, <slice credential>, {}) when done

Changes from AM API v2

This version of the AM API includes multiple changes since version 2 of the AM API. For experimenters, a few things are worth noting:

  • The old !CreateSliver operation has now been broken into 3 steps:
    • Allocate to reserve the resources
    • Provision to instantiate the resources, which may take time to complete
    • PerformOperationalAction(geni_start) to start (e.g. boot) the resources, which also may take time to complete
  • Use the intermediate geni_allocated state to coordinate reservations across aggregates, e.g. to ensure another aggregate can give you nodes to be the other end of a requested link
  • Multiple methods have been renamed, typically be removing the Sliver term from method names.
  • Sliver expiration is available in the return from multiple other methods, like Provision
  • You no longer use !ListResources to see the contents of your slice - use Describe instead. !ListResources is only for the AM's Ad RSpec.
  • SSH login names and keys should be available in manifest RSpecs in a standard format.
  • Slice name restrictions have been codified and standardized.
    • Slice names are <=19 characters, only alphanumeric plus hyphen (no hyphen in first character): '^[a-zA-Z0-9][-a-zA-Z0-9]+$'

Tool developers should also be aware:

  • The credentials argument to methods is now a struct, including a type and version for each credential. AMs should advertise which credential types they accept. SAs should advertise which type they provide.
  • Aggregates may have their own operational states and actions. The Ad RSpec should define these, probably by sliver_type.

Common Arguments and Returns

structs and optional arguments

Unless otherwise specified, all arguments and returns of type struct may include aggregate or resource-specific entries. As arguments, such options must be optional for the client to supply, with the aggregate providing a reasonable default.

datetime data type

All datetime arguments and returns in this API shall conform to RFC 3339. This represents a subset of the valid date/time strings permissible by the standard XML-RPC date/time data type, dateTime.iso8601.

  • Full date and time with explicit timezone: offset from UTC or in UTC)
  • e.g.: 1985-04-12T23:20:50.52Z or 1996-12-19T16:39:57-08:00

In the specification of this API, this is described as dateTime.rfc3339.

RSpec data type

Throughout this API, multiple arguments and returns are labeled as an RSpec. These fields shall be understood as XML documents following one of the schemas advertised in the return from GetVersion. All such RSpecs must pass an XML schema validator, must list all used schemas and namespaces within the document, using schemas that are publicly available. The GetVersion return advertises schemas for advertisment and request RSpecs; the schemas for manifest RSpecs are assumed to be available at the same base URL, but using a corresponding manifest schema.

A fully GENI AM API compliant aggregate will always support the GENI standard schemas for RSpecs, available at http://www.geni.net/resources/rspec. As of 4/2012, the current GENI RSpec version is 3. Aggregates are free to use an alternate format internally, but must accept and produce compliant RSpecs on demand.

The Aggregate Manager API requires this contract: Aggregates advertise the type and version of RSpec formats that they support. If available, they specify the schema, namespace and extensions combination which is the authoritative definition of that format. Clients of the API should understand that combination in order to know how to understand the resources available at that aggregate.

If an aggregate advertises a particular type/version (optionally defined with a combination of schema, namespace and extensions) in the geni_ad_rspec_versions attribute of GetVersion, then it promises to send a correct Advertisement RSpec in response to a ListResources call which supplies a geni_rspec_version option containing that type/version. (geni_rspec_version is a struct with 2 members, type and version. type and version are case-insensitive strings, matching those in geni_ad_rspec_versions).

If an Aggregate advertises a particular type/version (optionally defined with a combination of schema, namespace and extensions) in the geni_request_rspec_versions attribute of GetVersion then it promises to correctly honor an Allocate (was CreateSliver in API v2) call containing a request RSpec in the given format, and then to return a Manifest RSpec in the corresponding format (i.e. a GENI format request is answered with a GENI format manifest). The aggregate also promises to send a correctly formatted Manifest RSpec in response to a Describe call which supplies a valid slice URN or list of sliver URNs and an geni_rspec_version option containing that supported type/version.

In this API, such RSpec fields are labeled as type geni.rspec.

credentials

Many methods take an array of credentials. This is an array of credential type, version, and string value.

credentials = [
   {
    geni_type: <string>, 
    geni_version: <string>,
    geni_value: <string>,
    <others>
   }
]

Each credential (in geni_value) is defined as a signed document. A given list of credentials may contain credentials in multiple formats. The list may be empty. A given authorization policy at an AM may require 0, 1, or many credentials. Aggregates are required to allow credentials which are not used by local authorization policy or engines, using only credentials locally relevant.

  • An AM must pick credentials out of the list that it understands and be robust to receiving credentials it does not understand.
  • Current slice and user credentials will be recognizable for following the schema defined in Change Set K and GeniApiCredentials.
  • AMs are required to continue to accept current-format credentials.
    • In particular, a single standard slice credential remains sufficient for most authorization policies.
  • Other credential formats acceptable by some aggregates might include ABAC x509 Attribute certificates, eg.
  • AMs may get other authorization material from other sources: EG a future Credential Store service.

At least one subset of the credentials (e.g. a single SFA style slice credential) must authorize operations for the slice specified in slice_urn if that is an argument, or for the slice that contains the named slivers, if sliver urns are an argument, or a valid set of administrative credentials with sufficient privileges. When sliver_urns are supplied, all such slivers must belong to the same slice, over which the given credential set provides access. Credentials must be valid (signed by a valid GENI certificate authority either directly or by chain, not expired, and grant privileges to the client identified by the SSL client certificate). Each method requires specific privileges, which must be granted by the provided credentials. Note that the semantics of this argument is not clear: most implementations require a single credential to provide all needed privileges. Alternative interpretations might, for example, accumulate privileges from each valid credential to determine overall caller permissions. For details on GENI AM API format credentials, see the GENI wiki.

geni_end_time

The geni_end_time argument requests an expiration of the specified slivers. It is in dateTime.rfc3339 format (defined above). When an explicit argument, it is required, and aggregates must honor the request to the extent local policy permits. When an option in the options struct, clients may omit the option, and AMs may choose not to or be unable to honor this option, but may still succeed the overall request.

geni_best_effort

geni_best_effort: <XML-RPC boolean 1 or 0, default false (0)>

Clients may omit this option, but aggregates must honor the option if possible. This option modifies the way that the operation applies to all named slivers. By default (geni_best_effort=false), the operation must apply equally to all slivers, either succeeding or failing for all. When true, the aggregate may succeed the operation for some slivers, while failing the operation for other slivers.

geni_users

struct geni_users[] is an option for some methods.

Clients may omit this option. Aggregates should honor this option for any resource that accepts the provided login keys, and ignore it for other resources. This option is an array of user structs, which contain information about the users that might login to the sliver that the AM needs to know about. For example, this option is the mechanism by which users supply their SSH public keys, permitting SSH login to allocated nodes. In such cases, the corresponding manifest RSpec will contain the ssh-users element on each such node, showing the login username and applicable public keys. When this option is supplied, each struct must include the key 'keys', which is an array of strings and can be empty. The struct must also include the key 'urn', which is the user’s URN string. For example:

[
  {
    urn: urn:publicid:IDN+geni.net:gcf+user+alice
    keys: [<ssh key>, <ssh key>]
  },
  {
    urn: urn:publicid:IDN+geni.net:gcf+user+bob
    keys: [<ssh key>]
  }
]

options

An XML-RPC struct. For GetVersion only, this argument is optional. In all other methods, it is required. Only ListResources has required entries in the options struct. Aggregates are compliant with this API change by accepting this argument. Aggregates may accept entries to this struct. Aggregates should not require any new options to any method - they should always have a reasonable default for any such option. Aggregates should document new options arguments. The prefix geni_ is reserved for members that are part of this API specification. Implementations should choose an appropriate prefix to avoid conflicts.

urns[]

Several methods take some URNs to identify what to operate on. These methods are defined as accepting a list of arbitrary strings we call URNs. This API defines two kinds of URNs that may be supplied here, slice URNs and sliver URNs (see the GENI identifiers page, and Change Set K). Some aggregates may understand other URNs, but these are not defined or required here. Aggregates that accept only URNs defined by this API will return an error when given URNs not in one of those forms. This API requires that aggregates accept either a single slice URN, or 1+ sliver URNs that all belong to the same slice. Aggregates are not required to accept both a slice URN and sliver URNs, 2+ slice URNs, or a set of sliver URNs that crosses multiple slices. Some aggregates may choose to accept other such combinations of URNs. Aggregates that accept only arguments defined by this API will return an error when given more than 1 slice URN, a combination of both slice and sliver URNs, or a set of sliver URNs that belong to more than 1 slice.

Return Struct

code, value, and output together provide the standard return from all AM API methods.

code
A struct indicating the success or failure of this call at the Aggregate Manager. It consists of 1 required field and 2 optional fields.
  struct code = {
       int geni_code;
       [optional: string am_type;]
       [optional: int am_code;]
         }
value
Method-specific. Required on success. Optional on error.
output
On failure or error, this is required. Optional on success. This is an XML-RPC string with a human readable message explaining the result. Specifically, this might include an error string, a stacktrace, or other useful messages to help the experimenter resolve or report the failure or error. It is not defined on success, though aggregates are free to use it.

Implementations can add additional members to the return struct as desired. The prefix geni_ is reserved for members that are part of this API specification. Implementations should choose an appropriate prefix to avoid conflicts. Aggregates should document any additional return values.

Aggregates shall return consistent values for geni_code as described here. Aggregates wishing to be more specific may use the am_type and am_code values.

Success is always indicated using a geni_code value of 0.

On one of the error or failure cases listed in the table below, aggregates shall return the indicated error code.

Elements in code

geni_code
An integer supplying the GENI standard return code indicating the success or failure of this call. Error codes are standardized and defined in the attached XML document. Codes may be negative. A success return is defined as geni_code of 0.
am_type
Optional. A (case insensitive) string indicating the type of Aggregate Manager running locally. When an aggregate wants to return an aggregate specific return code in the am_code field, they supply an am_type to qualify the kind of aggregate specific return code they are supplying. This is the namespace of the aggregate specific return code. This field is optional: aggregates are not required to supply an aggregate specific return code, and clients need not look at it. This code further qualifies the kind of error or success that the aggregate is returning, as primarily defined by the value of geni_code. Standard values for am_type are defined in the attached XML document.
am_code
An integer supplying the more specific return code, relative to the aggregate type specified in am_type. This integer may be negative. Aggregates should document these codes publicly. This API does not specify how or where that documentation should be provided.

Aggregates are encouraged to use code values and output messages that help experimenters and tools distinguish between bad input, other experimenter error, temporary server errors, or server bugs.

GENI standard error codes are documented in the attached XML document, and listed below.

0 SUCCESS "Success"
1 BADARGS "Bad Arguments: malformed arguments"
2 ERROR "Error (other)"
3 FORBIDDEN "Operation Forbidden: eg supplied credentials do not provide sufficient privileges (on given slice)"
4 BADVERSION "Bad Version (eg of RSpec)"
5 SERVERERROR "Server Error"
6 TOOBIG "Too Big (eg request RSpec)"
7 REFUSED "Operation Refused"
8 TIMEDOUT "Operation Timed Out"
9 DBERROR "Database Error"
10 RPCERROR "RPC Error"
11 UNAVAILABLE "Unavailable (eg server in lockdown)"
12 SEARCHFAILED "Search Failed (eg for slice)"
13 UNSUPPORTED "Operation Unsupported"
14 BUSY "Busy (resource, slice); try again later"
15 EXPIRED "Expired (eg slice)"
16 INPROGRESS "In Progress"
17 ALREADYEXISTS "Already Exists (eg the slice}"

Aggregates are similarly encouraged to provide hints on how to fix bad requests using the value entry to experimenters on error or failures. For example, a failed RenewSliver call that failed because you are not allowed to renew your sliver that far in the future, might return a new date string in the value field that would be allowed. Similarly, a failed CreateSliver call might return a modified request RSpec in the value field.

Note that a malformed XML-RPC request should still raise an XML-RPC Fault, and other Faults dictated by the XML-RPC specification should still be raised. Aggregates should avoid raising an error (XML-RPC Fault) for application layer errors or any other cases where the XML-RPC specification does not require a Fault, but rather should attempt to return this struct, providing any error messages and stack traces in the output field or other additional fields. Certain XML-RPC errors may be returned using Faults or otherwise by the XML-RPC layer, or may more properly be returned using this struct in the application layer. In such cases, servers should use error codes with negative values. Selected such errors are listed below:

-32001 SERVERBUSY "Server is (temporarily) too busy; try again later"

Note also that servers may respond with other HTTP error codes, and clients must be prepared to deal with those situations. Specifically, a server that is busy might return HTTP code 503, or just refuse the connection.


Documenting Aggregate Additions

Aggregates are free to add additional return values or input options to support aggregate or resource specific functionality, or to innovate within the bounds of the AM API. Aggregates are encouraged to document any such new return values which they return or options arguments, to bootstrap coordination with clients, and provide documentation for human experimenters. One way to provide partial documentation, is to implement XML-RPC introspection. Through the use of method help, aggregates can provide human readable text describing return values. Alternatively or additionally, aggregates may document return values as part of their return from GetVersion. This API does not specify the format for advertising those extra return values in GetVersion.


Supporting Multiple API Versions

Aggregates are free to support multiple versions of the AM API. They do so by providing different URLs for each version of the API that they support. Aggregates should have a 'default' URL (the one typically advertised). That version runs whichever version of the API the server chooses (could be the latest, could be something else.)

When aggregates start supporting a new version of the API, they should keep running the old version of the API for a suitable transition period.

Aggregates running multiple versions of the API must advertise the URLs and versions of the API supported using the new GetVersion return as part of the value entry:

geni_api_versions: an XML-RPC struct containing 1+ entries of:
  Name: Integer - supported GENI AM API version
  Value: String - URL to the XML-RPC server implementing that version of the GENI AM API

For example

geni_api_versions: {
  1: <URL>,
  2: <Local URL, as this is API version 2>,
   ...
}

The entries indicate versions of the API that are supported, and URLs are absolute URLs where that version of the API is supported.

Sliver Allocation States

Many operations in this API create slivers or change the allocation status of slivers, and often return the current allocation status of each sliver. Valid sliver allocation states are:

  1. geni_unallocated (alternatively called 'null'). The sliver does not exist. This is the small black circle in typical state diagrams.
  2. geni_allocated (alternatively called 'offered' or 'promised'). The sliver exists, defines particular resources, and is in a sliver. The aggregate has not (if possible) done any time consuming or expensive work to instantiate the resources, provision them, or make it difficult to revert the slice to the state prior to allocating this sliver. This state is what the aggregate is offering the experimenter.
  3. geni_provisioned. The aggregate has started instantiating resources, and otherwise making changes to resources and the slice to make the resources available to the experimenter. At this point, operational states are valid to specify further when the resources are available for experimenter use.

geni_allocated represents resources that have been allocated to a slice without provisioning the resources. This represents a cheap and un-doable resource allocation. When a sliver is created and moved into state 2 (geni_allocated), the aggregate produces a manifest RSpec identifying which resources are included in the sliver. These resources are exclusively available to the containing sliver, but are not ready for use. In particular, allocating a sliver should be a cheap and quick operation, which the aggregate can readily un-do without impacting the state of slivers which are fully provisioned. For some aggregates, transitioning to this state may be a no-op.

States 2 and 3 (geni_allocated and geni_provisioned) have aggregate and possibly resource specific timeouts. By convention the geni_allocated state timeout is typically short. The geni_provisioned state timeout is the sliver expiration. If the client does not transition the sliver from geni_allocated to geni_provisioned before the end of the geni_allocated state timeout, the sliver reverts to geni_unallocated. If the experimenter needs more time, the experimenter should be allowed to request a renewal of either timeout. Note that typically the sliver expiration time (timeout for state 3, geni_provisioned) will be notably longer than the timeout for state 2, geni_allocated.

State 3, geni_provisioned, is the state of the sliver allocation after the aggregate begins to instantiate the sliver. Note that fully provisioning a sliver may take noticeable time. This state also includes a timeout - the sliver expiration time (which is not necessarily related to the time it takes to provision a resource). Renew extends this timeout. For some aggregates and resource types, moving to this state from state 2 (geni_allocated) may be a no-op.

If the transition from one state to another fails, the sliver shall remain in its original state.

  1. Allocate moves 1+ slivers from geni_unallocated (state 1) to geni_allocated (state 2). This method can be described as creating an instance of the state machine for each sliver. If the aggregate cannot fully satisfy the request, the whole request fails. This is a change from the version 2 CreateSliver, which also provisioned the resources, and 'started' them. That is Allocate does 1 of the 3 things that CreateSliver did previously.
  2. Delete moves 1+ slivers from either state 2 or 3 (geni_allocated or geni_provisioned), back to state 1 (geni_unallocated). This is similar to the AM API version 2 DeleteSliver.
  3. Renew, when given allocated slivers, requests an extended timeout for slivers in state 2 (geni_allocated).
  4. Renew can also be used to request an extended timeout for slivers in state 3 - the geni_provisioned state. That is, this method's semantics can be the same as RenewSliver from AM API v2.
  5. Provision moves 1+ slivers from state 2 (geni_allocated) to state 3 (geni_provisioned). This is some of what version 2 CreateSliver did. Note however that this does not 'start' the resources, or otherwise change their operational state. This method only fully instantiates the resources in the slice. This may be a no-op for some aggregates or resources.

These states apply to each sliver individually. Logically, the state transition methods then take a single sliver URN. For convenience, these methods accept a list of sliver URNs, or a slice URN as a simple alias for all slivers in this slice at this aggregate.

FIXME: Add picture

Sliver Operational States

The AM API defines a few operational states with particular semantics. AMs are not required to support them for a given set of resources, but if they use them, they must follow the given semantics. AMs are however STRONGLY encouraged to support them, to provide maximum utility. There is one state that AMs are required to support, geni_pending_allocation, for a sliver which has not been fully allocated and provisioned.

AMs may have their own operational states/state-machine internally. AMs are required to advertise such states and actions that experimenters may see or use, by using Ad RSpec extensions. Operational states which the experimenter never sees, need not be advertised. Operational states and actions are generally by resource type. The standard RSpec extension attaches such definitions to the sliver_type element of RSpecs.

States should be defined in terms of (a) whether the resource is accessible to the experimenter on the data or control planes, (b) whether an experimenter action is required to change from this state, and if so, (c) what action or actions are useful. If the resource will change states without explicit experimenter action, what is the expected next state on success.

Note that states represent the AM's view of the operational condition of the resource. This state represents what the AM has done or learned about the resource, but experimenter actions may cause failures that the AM does not know about.

There is no busy state. Instead, AMs are encouraged to define separate such transition states for each separate transition path, allowing experimenters to distinguish the start and end states for this transition.

shutdown is not an operational state for a sliver. The Shutdown() API method applies to an entire slice.

Operational states are generally only valid for slivers which have been provisioned (geni_provisioned allocation state).

GENI defined operational states:

  • geni_pending_allocation: A wait state. The sliver is still being allocated and provisioned, and other operational states are not yet valid. For example, the sliver is in allocation state geni_provisioned, but has not been fully provisioned (e.g., the VM has not been fully imaged). Once the sliver has been fully allocated, the AM will transition the sliver to some other valid operational state, as specified by the advertised operational state machine. Common next states are geni_notready, geni_ready, and geni_failed.
  • geni_notready: A final state. The resource is not usable / accessible by the experimenter, and requires explicit experimenter action before it is usable/accessible by the experimenter. For some resources, geni_start will move the resource out of this state and towards geni_ready.
  • geni_configuring: A wait state. The resource is in process of changing to geni_ready, and on success will do so without additional experimenter action. For example, the resource may be powering on.
  • geni_stopping: A wait state. The resource is in process of changing to geni_notready, and on success will do so without additional experimenter action. For example, the resource may be powering off.
  • geni_ready: A final state. The resource is usable/accessible by the experimenter, and ready for slice operations.
  • geni_ready_busy: A wait state. The resource is performing some operational action, but remains accessible/usable by the experimenter. Upon completion of the action, the resource will return to geni_ready.
  • geni_failed: A final state. Some operational action failed, rendering the resource unusable. An administrator action, undefined by this API, may be required to return the resource to another operational state.

Sliver Operational Actions

The API defines a few operational actions: these need not be supported. AMs are encouraged to support these if possible, but only if they can be supported following the defined semantics.

AMs may have their own operational states/state-machine internally. AMs are required to advertise such states and actions that experimenters may see or use, by using Ad RSpec extensions. Operational states which the experimenter never sees, need not be advertised. Operational states and actions are generally by resource type. The standard RSpec extension attaches such definitions to the sliver_type element of RSpecs.

Tools must use the operational states and actions advertisement to determine what operational actions to offer to experimenters, and what actions to perform for the experimenter. Tools may choose to offer actions which the tool does not understand, relying on the experimenter to understand the meaning of the new action.

Any operational action may fail. When this happens, the API method should return an error code. The sliver may remain in the original state. In some cases, the sliver may transition to the geni_failed state.

GENI defined operational actions:

  • geni_start: This action results in the sliver becoming geni_ready eventually. The operation may fail (move to geni_failed), or move through some number of transition states. See EG booting a VM.
  • geni_restart: This action results in the sliver becoming geni_ready eventually. The operation may fail (move to geni_failed), or move through some number of transition states. During this operation, the resource may or may not remain accessible. Dynamic state associated with this resource may be lost by performing this operation. See EG re-booting a VM.
  • geni_stop: This action results in the sliver becoming geni_notready eventually. The operation may fail (move to geni_failed), or move through some number of transition states. See EG powering down a VM.

GetVersion

Query static configuration information about this aggregate manager implementation, such as API and RSpec versions supported.

struct GetVersion([optional: struct options])

The options argument may be omitted entirely by clients.

Return struct:

      {
        int geni_api;
        struct geni_api_versions {
             URL <this API version #>; # value is a URL, name is a number
             [optional: other supported API versions and the URLs where they run]
        }
        array geni_request_rspec_versions of {
             string type;
             string version;
             string schema;
             string namespace;
             array extensions of string;
        };
        array geni_ad_rspec_versions of {
             string type;
             string version;
             string schema;
             string namespace;
             array extensions of string;
        };
        array geni_credential_types of {
             string geni_type <case insensitive>;
             string geni_version <containing an integer>;
       };
    }

ListResources

Retrieve RSpecs listing resources at this aggregate, an Advertisement RSpec of available resources.

struct ListResources(struct credentials[], struct options)

Where options include:

{
  boolean geni_available <optional>;
  boolean geni_compressed <optional>;
  struct geni_rspec_version {
    string type;
    string version;
  };
}

Note that all options may be omitted by the client, exception geni_rspec_version which is required. The aggregate must honor all supplied options.

credentials is the standard argument defined above.

Return: A geni.rspec advertisment RSpec.

Describe

AKA ListResources when supplied a slice URN.

Retrieve a manifest describing the resources contained by the entities named, e.g. a single slice or a set of the slivers in a slice.

struct Describe(string urns[], struct credentials[], struct options[])

Where options include:

{
  boolean geni_compressed <optional>;
  struct geni_rspec_version {
    string type;
    string version;
  };
}

Note that all options may be omitted by the client, exception geni_rspec_version which is required. The aggregate must honor all supplied options.

credentials is the standard argument defined elsewhere.

Note that the manifest RSpec for allocated slivers may contain less detail than for provisioned slivers.

Return struct:

{
   geni_rspec: <geni.rspec, Manifest - may be empty though)>
   geni_urn: <string slice urn, as requested>
   geni_slivers: [
               {
                  geni_sliver_urn: <string sliver urn>
                  geni_expires: <dateTime.rfc3339 allocation expiration string, as in geni_expires from SliversStatus>,
                  geni_allocation_status: <string sliver state - allocated or ?? >,
                  geni_operational_status: <string sliver operational state>
               },
               ...
         ]
}

Aggregates are expected to combine the manifests of all requested slivers into a single manifest RSpec. Note that a manifest returned here for only some of the slivers in a slice at this aggregate, may contain references to resources not described in this manifest (they are in other slivers). As a result, such manifests may not be directly usable as a subsequent request.

Allocate

AKA CreateSlivers() Request resources described by the given request RSpec to be allocated to the given slice. On success, one or more slivers are allocated, containing resources satisfying the request, and assigned to the given slice. The manifest RSpec describing those resources is returned.

struct Allocate(string slice_urn,
                    struct credentials[],
                    geni.rspec rspec,
                    struct options)

credentials is the standard argument defined above.

Options include:

{
  [optional geni_end_time: <dateTime.rfc3339>]
}

Return struct:

{
 geni_rspec: <geni.rspec manifest>,
 geni_slivers: [
        {
                  geni_sliver_urn: <string sliver urn>
                  geni_expires: <dateTime.rfc3339 allocation expiration string, as in geni_expires from SliversStatus>,
                  geni_allocation_status: <string sliver state - allocated or ?? >
        },
        ...
    ]
}

The manifest is a manifest of only newly allocated slivers.

Renew

AKA RenewSliver() or RenewAllocated Request that the named slivers be renewed, with their expiration extended. If possible, the aggregate should extend the slivers to the requested expiration time, or to a sooner time if policy limits apply. This method applies to slivers that are geni_allocated or to slivers that are geni_provisioned, though different policies may apply to slivers in the different states, resulting in much shorter max expiration times for geni_allocated slivers.

struct Renew(string urns[],
                    struct credentials[],
                    dateTime.rfc3339 expiration_time, 
                    struct options)

credentials is the standard argument defined above.

Options include geni_best_effort

Return list of structs:

[
  {
   geni_sliver_urn: <string>,
   geni_allocation_status: <string>,
   geni_operational_status: <string>,
   geni_expires: <dateTime.rfc3339 when the sliver expires from its current state>,
  },
  ...
]

UpdateAllocations

AKA UpdateAllocated() This method modifies a set of allocated slivers in place. The existing reservations are not lost if the newly requested allocations cannot be satisfied by the aggregate.

Details are suppressed pending agreement on this method.

Provision

AKA ProvisionSlivers() Request that the named geni_allocated slivers be made geni_provisioned, instantiating or otherwise realizing the resources, such that they have a valid geni_operational_status and may possibly be made geni_ready for experimenter use.

struct Provision(string urns[], struct credentials[],  
                                   struct options)

credentials is the standard argument defined above.

Options include:

  • geni_best_effort
  • geni_end_time
  • struct geni_users[]

Return struct:

  geni_rspec: <geni.rspec, RSpec manifest>,
  geni_slivers: 
  [
    {
     geni_sliver_urn: <string>,
     geni_allocation_status: <string>,
     geni_operational_status: <string>,
     geni_expires <dateTime.rfc3339 when the sliver expires from its current state>,
    },
    ...
  ],

FIXME: Is the returned manifest only for newly provisioned slivers? Or all slivers at this AM for this slice?

UpdateSlivers

AKA Update() This method requests a modification to 1 or more provisioned slivers. The slivers end up in a new geni_allocated+geni_provisioned state.

Details are suppressed pending agreement on this method.

Status

AKA SliverStatus Retrieve status information about the named slivers. This should be relatively dynamic data, not descriptive data as returned in the manifest RSpec.

struct Status(string urns[], struct credentials[], struct options)

credentials is the standard argument defined above.

Return:

{
  geni_urn: <slice URN>
  geni_slivers: [ 
                    { geni_sliver_urn: <sliver URN>
                      geni_allocation_status: <string, eg provisioned>
                      geni_operational_status: <string, eg ready>
                      geni_expires: <dateTime.rfc3339 of individual sliver expiration>
                      geni_error: <string, eg ''>,
                     },
                    { geni_sliver_urn: <sliver URN>
                      geni_allocation_status: <string, eg provisioned>
                      geni_operational_status: <string, eg ready>
                      geni_expires: <dateTime.rfc3339 of individual sliver expiration>
                      geni_error: <string, eg ''>,
                      }
                  ]
}

PerformOperationalAction

Perform the named operational action on the named slivers, possibly changing the geni_operational_status of the named slivers.

struct PerformOperationalAction (string urns[], struct credentials[], string action, 
                                                    struct options={})

credentials is the standard argument defined above.

Options include: geni_best_effort

Return list of structs:

[ {
        geni_sliver_urn : <string>,
        geni_allocation_status: <string, eg provisioned>
        geni_operational_status : <string>,
        geni_expires: <dateTime.rfc3339 of individual sliver expiration>
        }, 
        ... 
]
;

Delete

AKA DeleteSliver Delete the named slivers, making them geni_unallocated. Resources are de-provisioned. No further AM API operations may be performed on slivers that have been deleted.

struct Delete(string urns, struct credentials[], struct options)

credentials is the standard argument defined above.

Options include: geni_best_effort

Return list of structs:

[
  {
   geni_sliver_urn: <string>,
   geni_allocation_status: <string>,
   geni_expires: <dateTime.rfc3339 when the sliver expires from its current state>,
  },
  ...
]

Shutdown

Perform an emergency shutdown on the slice at this aggregate. Resources should be taken offline, such that experimenter access (on both the control and data plane) is cut off. No further actions on the slice should be possible at this aggregate, until an un-specified operator action restores the slice.

struct Shutdown(string slice_urn, struct credentials[], struct options)

credentials is the standard argument defined above.

Return: XML-RPC boolean