Internet DRAFT - draft-dcook-ppm-dap-interop-test-design
draft-dcook-ppm-dap-interop-test-design
Privacy Preserving Measurement D. Cook
Internet-Draft ISRG
Intended status: Informational 13 March 2023
Expires: 14 September 2023
DAP Interoperation Test Design
draft-dcook-ppm-dap-interop-test-design-03
Abstract
This document defines a common test interface for implementations of
the Distributed Aggregation Protocol for Privacy Preserving
Measurement (DAP) and describes how this test interface can be used
to perform interoperation testing between the implementations. Tests
are orchestrated with containers, and new test-only APIs are
introduced to provision DAP tasks and initiate processing.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at
https://divergentdave.github.io/draft-dcook-ppm-dap-interop-test-
design/draft-dcook-ppm-dap-interop-test-design.html. Status
information for this document may be found at
https://datatracker.ietf.org/doc/draft-dcook-ppm-dap-interop-test-
design/.
Discussion of this document takes place on the Privacy Preserving
Measurement Working Group mailing list (mailto:ppm@ietf.org), which
is archived at https://mailarchive.ietf.org/arch/browse/ppm/.
Subscribe at https://www.ietf.org/mailman/listinfo/ppm/.
Source for this draft and an issue tracker can be found at
https://github.com/divergentdave/draft-dcook-ppm-dap-interop-test-
design.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3
3. Container Interface . . . . . . . . . . . . . . . . . . . . . 4
4. Interoperation Test API . . . . . . . . . . . . . . . . . . . 4
4.1. Common Structures . . . . . . . . . . . . . . . . . . . . 5
4.1.1. VDAF . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1.2. Query . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Client . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2.1. /internal/test/ready . . . . . . . . . . . . . . . . 6
4.2.2. /internal/test/upload . . . . . . . . . . . . . . . . 7
4.3. Aggregator (Leader or Helper) . . . . . . . . . . . . . . 8
4.3.1. /internal/test/ready . . . . . . . . . . . . . . . . 8
4.3.2. /internal/test/endpoint_for_task . . . . . . . . . . 8
4.3.3. /internal/test/add_task . . . . . . . . . . . . . . . 9
4.4. Collector . . . . . . . . . . . . . . . . . . . . . . . . 11
4.4.1. /internal/test/ready . . . . . . . . . . . . . . . . 12
4.4.2. /internal/test/add_task . . . . . . . . . . . . . . . 12
4.4.3. /internal/test/collect_start . . . . . . . . . . . . 13
4.4.4. /internal/test/collect_poll . . . . . . . . . . . . . 14
4.5. Test Cases . . . . . . . . . . . . . . . . . . . . . . . 15
4.6. Other Test Considerations . . . . . . . . . . . . . . . . 16
4.7. Test Runner Operation . . . . . . . . . . . . . . . . . . 16
5. Implementation Status . . . . . . . . . . . . . . . . . . . . 17
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
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8. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
8.1. Normative References . . . . . . . . . . . . . . . . . . 18
8.2. Informative References . . . . . . . . . . . . . . . . . 18
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 19
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction
This document defines a common test interface for implementations of
the Distributed Aggregation Protocol for Privacy Preserving
Measurement [DAP]. This test interface facilitates interoperation
tests between different participating DAP implementations. As DAP
has four distinct protocol roles, (client, leader aggregator, helper
aggregator, and collector) manual interoperation testing between all
combinations of even a small number of DAP implementations could be
taxing. The goal of this document's common test interface is to
enable automation of these interoperation tests, so that different
participating implementations can be exchanged for each other, and
the same test suite can be re-run on different combinations of
implementations. Simplifying interoperation testing will aid in
identifying errors in implementations, identifying ambiguities in the
protocol specification, and reducing regressions in implementations.
Taking inspiration from QuicInteropRunner [SI2020], each
participating implementation provides one or more container images
adhering to a common interface. A test runner will start one
container for each protocol participant, configure networking between
the containers, and send various HTTP API requests. As part of this
common testing interface, the HTTP servers in the containers will
support some new test-only HTTP APIs, which will allow the test
runner to provision shared task parameters and secrets, as well as
trigger the start of different sub-protocols.
2. Conventions and Definitions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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3. Container Interface
Each participating DAP implementation may provide one or more
container images, one for each protocol role it implements. (client,
leader, helper, and collector) A list of available container images
will be maintained for each role. Implementations may want to submit
a single aggregator image in both the leader list and helper list.
The test runner will fetch each container using the given repository,
image name, and tag.
When the container’s entry point executable is run, it SHALL start up
an HTTP server listening on port 8080. In all cases, the container
will serve the endpoints described in Section 4 (particularly, the
subsection or subsections appropriate to its protocol role). In the
case of a helper or leader container, it SHALL also serve the
endpoints specified by [DAP] on a port (which MAY be the same port
8080 as used to serve the interoperation test API) at some relative
path. The container should run indefinitely, and the test runner
will terminate the container on completion of the test case. (While
DAP requires HTTPS connections, only using HTTP between containers
simplifies test setup. Putting TLS client/server interop out-of-
scope for these tests is acceptable, as it’s not of interest.)
Log output SHOULD be captured into the directory “/logs” inside the
container. This will be copied out to the host for inspection on
completion of the test case.
No environment variables or volume mounts will be provided to the
containers.
4. Interoperation Test API
Each container will have an HTTP server listening on port 8080 for
commands from the test runner. All requests MUST use the HTTP method
POST. Requests and responses for each endpoint listed below SHALL be
encoded JSON objects [RFC8729], with media type application/json.
All binary blobs (i.e. task IDs, batch IDs, HPKE configurations, and
VDAF verification keys) SHALL be encoded as strings with base64url
[RFC4648], inside the JSON objects. Any integer values in the
parameters, measurement, or aggregate result of a [VDAF] will be
encoded as strings in base 10 instead of as numbers. This avoids
incompatibilities due to limitations on the range of JSON numbers
that different implementations can process.
Each of these test APIs should return a status code of 200 OK if the
command was received, recognized, and parsed successfully, regardless
of whether any underlying DAP request succeeded or failed. The DAP-
level success or failure will be included in the test API response
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body. If a request is made to an endpoint starting with “/internal/
test/”, but not listed here, a status code of 404 Not Found SHOULD be
returned, to simplify the introduction of new test APIs.
4.1. Common Structures
4.1.1. VDAF
In multiple APIs defined below, the test runner will send the name of
a [VDAF], along with the parameters necessary to fully specify the
VDAF. These will be stored in a nested object, with the following
attributes (new type values and new keys will be added as new VDAFs
are defined).
+=========================+========================================+
| Key | Value |
+=========================+========================================+
| type | One of "Prio3Aes128Count", |
| | "Prio3Aes128CountVec", |
| | "Prio3Aes128Sum", |
| | "Prio3Aes128Histogram", or |
| | "Poplar1Aes128" |
+-------------------------+----------------------------------------+
| length (only present if | The length of the vectors being |
| type is | summed, (encoded in base 10 as a |
| "Prio3Aes128CountVec") | string) used to parameterize the |
| | Prio3Aes128CountVec VDAF. |
+-------------------------+----------------------------------------+
| bits (only present if | In the case of Prio3Aes128Sum, the bit |
| type is | width of the integers being summed, |
| "Prio3Aes128Sum" or | encoded in base 10 as a string. In |
| "Poplar1Aes128") | the case of Poplar1Aes128, the bit |
| | length of the input, encoded in base |
| | 10 as a string. |
+-------------------------+----------------------------------------+
| buckets (only present | An array of histogram bucket |
| if type is | boundaries, (encoded in base 10 as |
| "Prio3Aes128Histogram") | strings) used to parameterize the |
| | Prio3Aes128Histogram VDAF. |
+-------------------------+----------------------------------------+
Table 1: VDAF JSON object structure
4.1.2. Query
In multiple APIs defined below, the test runner will need to send a
query type, and in one API, it will need to send a query type along
with the associated query parameters.
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Query types are represented in API requests as numbers, following the
values of the QueryType enum in [DAP].
Queries are represented in API requests as a nested object, with the
following attributes (new keys will be added as new query types are
defined).
+============================+===============================+
| Key | Value |
+============================+===============================+
| type | A number, representing a |
| | query type, as described |
| | above. |
+----------------------------+-------------------------------+
| batch_interval_start (only | The start of the batch |
| present if type is 1, for | interval, represented as a |
| time interval queries) | number equal to the number of |
| | seconds since the UNIX epoch. |
+----------------------------+-------------------------------+
| batch_interval_duration | The duration of the batch |
| (only present if type is | interval in seconds, as a |
| 1, for time interval | number. |
| queries) | |
+----------------------------+-------------------------------+
| subtype (only present if | 0 or 1, representing one of |
| type is 2, for fixed size | the values of the |
| queries) | FixedSizeQueryType enum in |
| | [DAP]. |
+----------------------------+-------------------------------+
| batch_id (only present if | A base64url-encoded DAP |
| type is 2, for fixed size | BatchID. |
| queries, and subtype is 0, | |
| for "by batch ID" queries) | |
+----------------------------+-------------------------------+
Table 2: Query JSON object structure
4.2. Client
4.2.1. /internal/test/ready
The test runner will POST an empty object (i.e. {}) to this endpoint
to check if the client container is ready to serve requests. If it
is ready, it MUST return a status code of 200 OK.
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4.2.2. /internal/test/upload
Upon receipt of this command, the client container will construct a
DAP report with the given configuration and measurement, and submit
it. The client container will send its response to the test runner
once report submission has either succeeded or permanently failed.
+================+==================================================+
| Key | Value |
+================+==================================================+
| task_id | A base64url-encoded DAP TaskId. |
+----------------+--------------------------------------------------+
| leader | The leader's endpoint URL. |
+----------------+--------------------------------------------------+
| helper | The helper's endpoint URL. |
+----------------+--------------------------------------------------+
| vdaf | An object, with the layout given in |
| | Table 1. This determines the VDAF to be |
| | used when constructing a report. |
+----------------+--------------------------------------------------+
| measurement | If the VDAF's type is "Prio3Aes128Count": |
| | "0" or "1". If the VDAF's type is |
| | "Prio3Aes128CountVec": an array of strings, |
| | each of which is "0" or "1". If the VDAF's |
| | type is "Prio3Aes128Sum": a string |
| | (representing an integer in base 10). If |
| | the VDAF's type is "Prio3Aes128Histogram": |
| | a string (representing an integer in base |
| | 10). If the VDAF's type is |
| | "Poplar1Aes128": an array of Booleans. |
+----------------+--------------------------------------------------+
| time | If present, this provides a substitute time |
| (optional) | value that should be used when constructing |
| | the report. If not present, the current |
| | system time should be used, as per normal. |
| | The time is represented as a number, with a |
| | value of the number of seconds since the |
| | UNIX epoch. |
+----------------+--------------------------------------------------+
| time_precision | A number, providing the precision in |
| | seconds of report timestamps. |
+----------------+--------------------------------------------------+
Table 3: Request JSON object structure
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+============+==============================================+
| Key | Value |
+============+==============================================+
| status | "success" if the report was submitted to the |
| | leader successfully, or "error" otherwise. |
+------------+----------------------------------------------+
| error | An optional error message, to assist in |
| (optional) | troubleshooting. This will be included in |
| | the test runner logs. |
+------------+----------------------------------------------+
Table 4: Response JSON object structure
4.3. Aggregator (Leader or Helper)
4.3.1. /internal/test/ready
The test runner will POST an empty object (i.e. {}) to this endpoint
to check if the aggregator container is ready to serve requests. If
it is ready, it MUST return a status code of 200 OK.
4.3.2. /internal/test/endpoint_for_task
Request the base URL for DAP endpoints for a new task. This API will
be invoked immediately before /internal/test/add_task (see
Section 4.3.3), to determine the endpoint URLs of the aggregators.
If the aggregator uses a common set of DAP endpoints for all tasks,
it could always return the same value, such as the relative URL /.
Alternately, implementations may wish to generate new endpoints for
each task, derive the endpoint based on the TaskId, etc.
The test runner will provide the hostname at which the aggregator is
externally reachable. If the aggregator returns a relative URL, the
test runner will combine it with the hostname into an absolute URL,
assuming that the port is 8080. Otherwise, the aggregator can
incorporate the hostname into an absolute URL and return that.
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+==========+===================================================+
| Key | Value |
+==========+===================================================+
| task_id | A base64url-encoded DAP TaskId. |
+----------+---------------------------------------------------+
| role | Either "leader" or "helper". |
+----------+---------------------------------------------------+
| hostname | This aggregator's hostname in the interoperation |
| | test environment. This may optionally be used in |
| | constructing the endpoint URL as an absolute URL. |
+----------+---------------------------------------------------+
Table 5: Request JSON object structure
+============+==================================================+
| Key | Value |
+============+==================================================+
| status | "success" if the endpoint was successfully |
| | selected or set up, or "error" otherwise. |
+------------+--------------------------------------------------+
| error | An optional error message, to assist in |
| (optional) | troubleshooting. This will be included in the |
| | test runner logs. |
+------------+--------------------------------------------------+
| endpoint | A relative or absolute URL, specifying the DAP |
| | aggregator endpoint that should be used for this |
| | task. If the test runner receives a relative |
| | URL, it will transform it into an absolute URL |
| | before performing the next phase of task setup. |
+------------+--------------------------------------------------+
Table 6: Response JSON object structure
4.3.3. /internal/test/add_task
Register a task with the aggregator, with the given configuration and
secrets.
The HPKE keypair generated for this task should use the mandatory-to-
implement algorithms in section 6 of [DAP], for broad compatibility.
+================================+===============================+
| Key | Value |
+================================+===============================+
| task_id | A base64url-encoded DAP |
| | TaskId. |
+--------------------------------+-------------------------------+
| leader | The leader's endpoint URL. |
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| | The test runner will ensure |
| | this is an absolute URL. |
+--------------------------------+-------------------------------+
| helper | The helper's endpoint URL. |
| | The test runner will ensure |
| | this is an absolute URL. |
+--------------------------------+-------------------------------+
| vdaf | An object, with the layout |
| | given in Table 1. This |
| | determines the task's VDAF. |
+--------------------------------+-------------------------------+
| leader_authentication_token | The authentication token that |
| | is shared with the other |
| | aggregator, as a string. |
| | This string MUST be safe for |
| | use as an HTTP header value. |
| | When the leader sends HTTP |
| | requests to the helper, it |
| | MUST include this value in a |
| | header named DAP-Auth-Token. |
+--------------------------------+-------------------------------+
| collector_authentication_token | The authentication token that |
| (only present if role is | is shared between the leader |
| "leader") | and collector, as a string. |
| | This string MUST be safe for |
| | use as an HTTP header value. |
| | When the collector sends HTTP |
| | requests to the leader, it |
| | MUST include this value in a |
| | header named DAP-Auth-Token. |
+--------------------------------+-------------------------------+
| role | Either "leader" or "helper". |
+--------------------------------+-------------------------------+
| vdaf_verify_key | The VDAF verification key |
| | shared by the two |
| | aggregators, encoded with |
| | base64url. |
+--------------------------------+-------------------------------+
| max_batch_query_count | A number, providing the |
| | maximum number of times any |
| | report can be included in a |
| | collect request. |
+--------------------------------+-------------------------------+
| query_type | A number, representing the |
| | task's query type, as |
| | described in Section 4.1.2. |
+--------------------------------+-------------------------------+
| min_batch_size | A number, providing the |
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| | minimum number of reports |
| | that must be in a batch for |
| | it to be collected. |
+--------------------------------+-------------------------------+
| max_batch_size (only present | A number, providing the |
| if query_type is 2, for fixed | maximum number of reports |
| size queries) | that may be in a batch for it |
| | to be collected. |
+--------------------------------+-------------------------------+
| time_precision | A number, providing the |
| | precision in seconds of |
| | report timestamps. For tasks |
| | using the time interval query |
| | type, the batch interval's |
| | duration will always be a |
| | multiple of this value. |
+--------------------------------+-------------------------------+
| collector_hpke_config | The collector's HPKE |
| | configuration, encoded in |
| | base64url, for encryption of |
| | aggregate shares. |
+--------------------------------+-------------------------------+
| task_expiration | A number, providing the time |
| | when clients are no longer |
| | expected to upload to this |
| | task. This is represented as |
| | a number of seconds since the |
| | UNIX epoch. |
+--------------------------------+-------------------------------+
Table 7: Request JSON object structure
+============+=========================================+
| Key | Value |
+============+=========================================+
| status | "success" if the task was successfully |
| | set up, or "error" otherwise. (for |
| | example, if the VDAF was not supported) |
+------------+-----------------------------------------+
| error | An optional error message, to assist in |
| (optional) | troubleshooting. This will be included |
| | in the test runner logs. |
+------------+-----------------------------------------+
Table 8: Response JSON object structure
4.4. Collector
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4.4.1. /internal/test/ready
The test runner will POST an empty object (i.e. {}) to this endpoint
to check if the collector container is ready to serve requests. If
it is ready, it MUST return a status code of 200 OK.
4.4.2. /internal/test/add_task
Register a task with the collector, with the given configuration.
Returns the collector’s HPKE configuration for this task.
The HPKE keypair generated for this task should use the mandatory-to-
implement algorithms in section 6 of [DAP], for broad compatibility.
+================================+===============================+
| Key | Value |
+================================+===============================+
| task_id | A base64url-encoded DAP |
| | TaskId. |
+--------------------------------+-------------------------------+
| leader | The leader's endpoint URL. |
+--------------------------------+-------------------------------+
| vdaf | An object, with the layout |
| | given in Table 1. This |
| | determines the task's VDAF. |
+--------------------------------+-------------------------------+
| collector_authentication_token | The authentication token that |
| | is shared between the leader |
| | and collector, as a string. |
| | This string MUST be safe for |
| | use as an HTTP header value. |
| | When the collector sends HTTP |
| | requests to the leader, it |
| | MUST include this value in a |
| | header named DAP-Auth-Token. |
+--------------------------------+-------------------------------+
| query_type | A number, representing the |
| | task's query type, as |
| | described in Section 4.1.2. |
+--------------------------------+-------------------------------+
Table 9: Request JSON object structure
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+=======================+=========================================+
| Key | Value |
+=======================+=========================================+
| status | "success" if the task was successfully |
| | set up, or "error" otherwise. (for |
| | example, if the VDAF was not supported) |
+-----------------------+-----------------------------------------+
| error (optional) | An optional error message, to assist in |
| | troubleshooting. This will be included |
| | in the test runner logs. |
+-----------------------+-----------------------------------------+
| collector_hpke_config | The collector's HPKE configuration, |
| (if successful) | encoded in base64url, for encryption of |
| | aggregate shares. |
+-----------------------+-----------------------------------------+
Table 10: Response JSON object structure
4.4.3. /internal/test/collect_start
Send a collect request to the leader with the provided parameters,
and return a handle to the test runner identifying this collect
request. The test runner will provide this handle to the collector
in subsequent /internal/test/collect_poll requests (see
Section 4.4.4).
+===========+===================================================+
| Key | Value |
+===========+===================================================+
| task_id | A base64url-encoded DAP TaskId. |
+-----------+---------------------------------------------------+
| agg_param | A base64url-encoded aggregation parameter. |
+-----------+---------------------------------------------------+
| query | An object, with the layout given in Table 2. |
| | This provides the collect request's query, and in |
| | turn determines which reports should be included. |
+-----------+---------------------------------------------------+
Table 11: Request JSON object structure
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+=============+======================================+
| Key | Value |
+=============+======================================+
| status | "success" if the collect request |
| | succeeded, or "error" otherwise. |
+-------------+--------------------------------------+
| error | An optional error message, to assist |
| (optional) | in troubleshooting. This will be |
| | included in the test runner logs. |
+-------------+--------------------------------------+
| handle (if | A handle produced by the collector |
| successful) | to refer to this collect request. |
| | This must be a string. |
+-------------+--------------------------------------+
Table 12: Response JSON object structure
4.4.4. /internal/test/collect_poll
The test runner sends this command to a collector to poll for
completion of the collect job associated with the provided handle.
The collector provides the status and (if available) result to the
test runner.
+========+=========================================+
| Key | Value |
+========+=========================================+
| handle | The handle for a collect request from a |
| | previous invocation of /internal/test/ |
| | collect_start. (see Section 4.4.3) |
+--------+-----------------------------------------+
Table 13: Request JSON object structure
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+==============+==================================================+
| Key | Value |
+==============+==================================================+
| status | Either "complete" if the result is ready, "in |
| | progress" if the result is not yet ready, or |
| | "error" if an error occurred. |
+--------------+--------------------------------------------------+
| error | An optional error message, to assist in |
| (optional) | troubleshooting. This will be included in the |
| | test runner logs. |
+--------------+--------------------------------------------------+
| batch_id (if | The identifier of the batch that was collected, |
| the task | encoded with base64url. |
| uses fixed | |
| size | |
| queries) | |
+--------------+--------------------------------------------------+
| report_count | A number, reflecting the count of client reports |
| (if | included in this aggregated result. |
| complete) | |
+--------------+--------------------------------------------------+
| result (if | The result of the aggregation. If the VDAF is |
| complete) | of type Prio3Aes128Count or Prio3Aes128Sum, this |
| | will be a string, representing an integer in |
| | base 10. If the VDAF is of type |
| | Prio3Aes128CountVec, Prio3Aes128Histogram, or |
| | Poplar1Aes128, this will be an array of strings, |
| | each representing an integer in base 10. |
+--------------+--------------------------------------------------+
Table 14: Response JSON object structure
4.5. Test Cases
Test cases could be written to cover the following scenarios.
* Test successful aggregations with each VDAF.
* Test an aggregation over a few hundred or thousand reports, to
exercise the aggregators' division of reports into aggregation
jobs.
* Test that uploading a report with a time far in the future is
rejected.
* Confirm that leaders and helpers reject requests with respective
authentication tokens that are incorrect.
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* Test enforcement of max_batch_query_count by making overlapping
collect requests.
* Perform an entire aggregation and collect flow, attempt to upload
a late report that falls into the same collect interval, and test
that performing the collect request a second time yields the same
result.
* Attempt to upload a canned report from the test runner more than
once, and confirm that anti-replay measures were effective by
inspecting the aggregation result.
4.6. Other Test Considerations
All test cases should automatically fail after a generous timeout.
It is the responsibility of the test runner to wait for all
containers to start up and respond successfully to a request to
/internal/test/ready before sending any further commands.
Aggregator URLs will be constructed by the test runner with hostnames
that resolve to the respective containers within the container
network.
Once a future [DAP] draft solves the issue of retries in the
aggregate flow, a reverse proxy could be introduced in front of each
aggregator to inject failures when sending requests or responses, to
test the protocol's resilience. (It is known such a test would fail
with the current protocol.)
4.7. Test Runner Operation
The following sequence outlines how the test runner will use the
above APIs on port 8080 of each container to perform a typical
integration test, executing a successful aggregation.
1. Create and start containers.
2. Set up networking between containers.
3. Try sending /internal/test/ready requests to each container, and
retry until they succeed.
4. Generate a random TaskId, random authentication tokens, and a
VDAF verification key.
5. Send a /internal/test/endpoint_for_task request (Section 4.3.2)
to the leader.
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6. Send a /internal/test/endpoint_for_task request (Section 4.3.2)
to the helper.
7. Construct aggregator URLs using the above responses.
8. Send a /internal/test/add_task request (Section 4.4.2) to the
collector. (the collector generates an HPKE key pair as a side-
effect)
9. Send a /internal/test/add_task request (Section 4.3.3) to the
leader.
10. Send a /internal/test/add_task request (Section 4.3.3) to the
helper.
11. Send one or more /internal/test/upload requests (Section 4.2.2)
to the client.
12. Send one or more /internal/test/collect_start requests
(Section 4.4.3) to the collector. (this provides a handle for
use in the next step)
13. Send /internal/test/collect_poll requests (Section 4.4.4) to the
collector, polling until each collection is completed. (the
collector will provide the calculated aggregate results)
14. Stop containers.
15. Copy logs out of each container.
16. Delete containers, and clean up container networking resources.
5. Implementation Status
[Janus], [divviup-ts], and [Daphne] currently implement a version of
this test interface. [REF-IMPL] is a reference implementation of a
test runner using this interface.
Additional DAP implementations would be warmly welcomed.
6. Security Considerations
Any DAP implementation that adopts this testing interface should
ensure that the test-only APIs described herein are only present in
software used for testing purposes, and not in production systems.
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7. IANA Considerations
This document has no IANA actions.
8. References
8.1. Normative References
[DAP] Geoghegan, T., Patton, C., Rescorla, E., and C. A. Wood,
"Distributed Aggregation Protocol for Privacy Preserving
Measurement", Work in Progress, Internet-Draft, draft-
ietf-ppm-dap-03, 9 December 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-ppm-dap-
03>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
<https://www.rfc-editor.org/rfc/rfc4648>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC8729] Housley, R., Ed. and L. Daigle, Ed., "The RFC Series and
RFC Editor", RFC 8729, DOI 10.17487/RFC8729, February
2020, <https://www.rfc-editor.org/rfc/rfc8729>.
[VDAF] Barnes, R., Patton, C., and P. Schoppmann, "Verifiable
Distributed Aggregation Functions", Work in Progress,
Internet-Draft, draft-irtf-cfrg-vdaf-03, 24 August 2022,
<https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-
vdaf-03>.
8.2. Informative References
[Daphne] "Implementation of DAP", 15 December 2022,
<https://github.com/cloudflare/daphne>.
[divviup-ts]
"TypeScript client for https://divviup.org", 5 October
2022, <https://github.com/divviup/divviup-ts>.
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[Janus] "Experimental implementation of the DAP specification", 25
August 2022, <https://github.com/divviup/janus>.
[REF-IMPL] "Reference DAP interoperation test harness", 4 October
2022, <https://github.com/divergentdave/dap-interop-test-
runner>.
[SI2020] Seemann, M. and J. Iyengar, "Automating QUIC
Interoperability Testing", 10 August 2020,
<https://research.protocol.ai/publications/automating-
quic-interoperability-testing/seemann2020.pdf>.
Acknowledgments
Thanks to Brandon Pitman, Christopher Patton, and Tim Geoghegan for
feedback and contributions.
Author's Address
David Cook
ISRG
Email: dcook@divviup.org
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