grpc/doc/interop-test-descriptions.md

Interoperability Test Case Descriptions

Client and server use test.proto and the gRPC over HTTP/2 v2 protocol.

Client

Clients implement test cases that test certain functionally. Each client is provided the test case it is expected to run as a command-line parameter. Names should be lowercase and without spaces.

Clients should accept these arguments:

• --server_host=HOSTNAME
  • The server host to connect to. For example, "localhost" or "127.0.0.1"
• --server_host_override=HOSTNAME
  • The server host to claim to be connecting to, for use in TLS and HTTP/2 :authority header. If unspecified, the value of --server_host will be used
• --server_port=PORT
  • The server port to connect to. For example, "8080"
• --test_case=TESTCASE
  • The name of the test case to execute. For example, "empty_unary"
• --use_tls=BOOLEAN
  • Whether to use a plaintext or encrypted connection
• --use_test_ca=BOOLEAN
  • Whether to replace platform root CAs with ca.pem as the CA root
• --default_service_account=ACCOUNT_EMAIL
  • Email of the GCE default service account. Only applicable for compute_engine_creds test.
• --oauth_scope=SCOPE
  • OAuth scope. For example, "https://www.googleapis.com/auth/xapi.zoo"
• --service_account_key_file=PATH
  • The path to the service account JSON key file generated from GCE developer console.

Clients must support TLS with ALPN. Clients must not disable certificate checking.

empty_unary

This test verifies that implementations support zero-size messages. Ideally, client implementations would verify that the request and response were zero bytes serialized, but this is generally prohibitive to perform, so is not required.

Server features:

• EmptyCall

Procedure:

1. Client calls EmptyCall with the default Empty message

Asserts:

• call was successful
• response is non-null

It may be possible to use UnaryCall instead of EmptyCall, but it is harder to ensure that the proto serialized to zero bytes.

large_unary

This test verifies unary calls succeed in sending messages, and touches on flow control (even if compression is enabled on the channel).

Server features:

• UnaryCall
• Compressable Payload

Procedure:

1. Client calls UnaryCall with:

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
   }
   

Asserts:

• call was successful
• response payload type is COMPRESSABLE
• response payload body is 314159 bytes in size
• clients are free to assert that the response payload body contents are zero and comparing the entire response message against a golden response

client_streaming

This test verifies that client-only streaming succeeds.

Server features:

• StreamingInputCall
• Compressable Payload

Procedure:

1. Client calls StreamingInputCall

2. Client sends:

   {
     payload:{
       body: 27182 bytes of zeros
     }
   }
   

3. Client then sends:

   {
     payload:{
       body: 8 bytes of zeros
     }
   }
   

4. Client then sends:

   {
     payload:{
       body: 1828 bytes of zeros
     }
   }
   

5. Client then sends:

   {
     payload:{
       body: 45904 bytes of zeros
     }
   }
   

6. Client halfCloses

Asserts:

• call was successful
• response aggregated_payload_size is 74922

server_streaming

This test verifies that server-only streaming succeeds.

Server features:

• StreamingOutputCall
• Compressable Payload

Procedure:

1. Client calls StreamingOutputCall with:

   {
     response_type:COMPRESSABLE
     response_parameters:{
       size: 31415
     }
     response_parameters:{
       size: 9
     }
     response_parameters:{
       size: 2653
     }
     response_parameters:{
       size: 58979
     }
   }
   

Asserts:

• call was successful
• exactly four responses
• response payloads are COMPRESSABLE
• response payload bodies are sized (in order): 31415, 9, 2653, 58979
• clients are free to assert that the response payload body contents are zero and comparing the entire response messages against golden responses

ping_pong

This test verifies that full duplex bidi is supported.

Server features:

• FullDuplexCall
• Compressable Payload

Procedure:

1. Client calls FullDuplexCall with:

   {
     response_type: COMPRESSABLE
     response_parameters:{
       size: 31415
     }
     payload:{
       body: 27182 bytes of zeros
     }
   }
   

2. After getting a reply, it sends:

   {
     response_type: COMPRESSABLE
     response_parameters:{
       size: 9
     }
     payload:{
       body: 8 bytes of zeros
     }
   }
   

3. After getting a reply, it sends:

   {
     response_type: COMPRESSABLE
     response_parameters:{
       size: 2653
     }
     payload:{
       body: 1828 bytes of zeros
     }
   }
   

4. After getting a reply, it sends:

   {
     response_type: COMPRESSABLE
     response_parameters:{
       size: 58979
     }
     payload:{
       body: 45904 bytes of zeros
     }
   }
   

Asserts:

• call was successful
• exactly four responses
• response payloads are COMPRESSABLE
• response payload bodies are sized (in order): 31415, 9, 2653, 58979
• clients are free to assert that the response payload body contents are zero and comparing the entire response messages against golden responses

empty_stream

This test verifies that streams support having zero-messages in both directions.

Server features:

• FullDuplexCall

Procedure:

1. Client calls FullDuplexCall and then half-closes

Asserts:

• call was successful
• exactly zero responses

compute_engine_creds

This test is only for cloud-to-prod path.

This test verifies unary calls succeed in sending messages while using Service Credentials from GCE metadata server. The client instance needs to be created with desired oauth scope.

The test uses --default_service_account with GCE service account email and --oauth_scope with the OAuth scope to use. For testing against grpc-test.sandbox.google.com, "https://www.googleapis.com/auth/xapi.zoo" should be passed in as --oauth_scope.

Server features:

• UnaryCall
• Compressable Payload
• Echo Authenticated Username
• Echo OAuth Scope

Procedure:

1. Client configures channel to use GCECredentials

2. Client calls UnaryCall on the channel with:

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
     fill_username: true
     fill_oauth_scope: true
   }
   

Asserts:

• call was successful
• received SimpleResponse.username equals the value of --default_service_account flag
• received SimpleResponse.oauth_scope is in --oauth_scope
• response payload body is 314159 bytes in size
• clients are free to assert that the response payload body contents are zero and comparing the entire response message against a golden response

service_account_creds

This test is only for cloud-to-prod path.

This test verifies unary calls succeed in sending messages while using JWT signing keys (redeemed for OAuth2 access tokens by the auth implementation)

The test uses --service_account_key_file with the path to a json key file downloaded from https://console.developers.google.com, and --oauth_scope to the oauth scope. For testing against grpc-test.sandbox.google.com, "https://www.googleapis.com/auth/xapi.zoo" should be passed in as --oauth_scope.

Server features:

• UnaryCall
• Compressable Payload
• Echo Authenticated Username
• Echo OAuth Scope

Procedure:

1. Client configures the channel to use ServiceAccountCredentials.

2. Client calls UnaryCall with:

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
     fill_username: true
     fill_oauth_scope: true
   }
   

Asserts:

• call was successful
• received SimpleResponse.username is in the json key file read from --service_account_key_file
• received SimpleResponse.oauth_scope is in --oauth_scope
• response payload body is 314159 bytes in size
• clients are free to assert that the response payload body contents are zero and comparing the entire response message against a golden response

jwt_token_creds

This test is only for cloud-to-prod path.

This test verifies unary calls succeed in sending messages while using JWT token (created by the project's key file)

Test caller should set flag --service_account_key_file with the path to json key file downloaded from https://console.developers.google.com.

Server features:

• UnaryCall
• Compressable Payload
• Echo Authenticated Username
• Echo OAuth Scope

Procedure:

1. Client configures the channel to use JWTTokenCredentials.

2. Client calls UnaryCall with:

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
     fill_username: true
   }
   

Asserts:

• call was successful
• received SimpleResponse.username is in the json key file read from --service_account_key_file
• response payload body is 314159 bytes in size
• clients are free to assert that the response payload body contents are zero and comparing the entire response message against a golden response

oauth2_auth_token

Similar to the other auth tests, this test is only for cloud-to-prod path.

This test verifies unary calls succeed in sending messages using an OAuth2 token that is obtained OOB. For the purpose of the test, the OAuth2 token is actually obtained from the service account credentials via the language-specific authorization library.

The difference between this test and the other auth tests is that rather than configuring the test client with ServiceAccountCredentials directly, the test first uses the authorization library to obtain an authorization token.

The test

• uses the flag--service_account_key_file with the path to a json key file downloaded from https://console.developers.google.com. Alternately, if using a usable auth implementation, it may specify the file location in the environment variable GOOGLE_APPLICATION_CREDENTIALS
• uses the flag --oauth_scope for the oauth scope. For testing against grpc-test.sandbox.google.com, "https://www.googleapis.com/auth/xapi.zoo" should be passed as the --oauth_scope.

Server features:

• UnaryCall
• Compressable Payload
• Echo Authenticated Username
• Echo OAuth Scope

Procedure:

1. Client use the auth library to obtain an authorization token

2. Client calls UnaryCall, attaching the authorization token obtained in step1, with the following message

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
     fill_username: true
     fill_oauth_scope: true
   }
   

Asserts:

• call was successful
• received SimpleResponse.username is in the json key file used by the auth library to obtain the authorization token
• received SimpleResponse.oauth_scope is in --oauth_scope
• response payload body is 314159 bytes in size
• clients are free to assert that the response payload body contents are zero and comparing the entire response message against a golden response

Metadata (TODO: fix name)

Status: Not yet implementable

This test verifies that custom metadata in either binary or ascii format can be sent in header and trailer.

Server features:

• UnaryCall
• Compressable Payload
• Ability to receive custom metadata from client in header and send custom data back to client in both header and trailer. (TODO: this is not defined)

Procedure:

1. While sending custom metadata (ascii + binary) in the header, client calls UnaryCall with:

   {
     response_type: COMPRESSABLE
     response_size: 314159
     payload:{
       body: 271828 bytes of zeros
     }
   }
   

Asserts:

• call was successful
• custom metadata is echoed back in the response header.
• custom metadata is echoed back in the response trailer.

status_code_and_message

Status: Not yet implementable

This test verifies unary calls succeed in sending messages, and propagates back status code and message sent along with the messages.

Server features:

• UnaryCall

Procedure:

1. Client calls UnaryCall with:

   {
     response_status:{
       code: 2
       message: "test status message"
     }
   }
   

Asserts:

• received status code is the same with sent code
• received status message is the same with sent message

unimplemented_method

Status: Not yet implementable

This test verifies calling unimplemented RPC method returns unimplemented status.

Procedure:

• Client calls UnimplementedCall with:

  {
    response_type: COMPRESSABLE
    response_size: 314159
    payload:{
      body: 271828 bytes of zeros
    }
  }
  

Asserts:

• received status code is 12 (UNIMPLEMENTED)
• received status message is empty or null/unset

cancel_after_begin

This test verifies that a request can be cancelled after metadata has been sent but before payloads are sent.

Server features:

• StreamingInputCall

Procedure:

1. Client starts StreamingInputCall
2. Client immediately cancels request

Asserts:

• Call completed with status CANCELLED

cancel_after_first_response

This test verifies that a request can be cancelled after receiving a message from the server.

Server features:

• FullDuplexCall
• Compressable Payload

Procedure:

1. Client starts FullDuplexCall with

   {
     response_type: COMPRESSABLE
     response_parameters:{
       size: 31415
     }
     payload:{
       body: 27182 bytes of zeros
     }
   }
   

2. After receiving a response, client cancels request

Asserts:

• Call completed with status CANCELLED

timeout_on_sleeping_server

This test verifies that an RPC request whose lifetime exceeds its configured timeout value will end with the DeadlineExceeded status.

Server features:

• FullDuplexCall

Procedure:

1. Client calls FullDuplexCall with the following request and sets its timeout to 1ms.

   {
     payload:{
       body: 27182 bytes of zeros
     }
   }
   

Asserts:

• Call completed with status DEADLINE_EXCEEDED.

concurrent_large_unary

Status: TODO

Client performs 1000 large_unary tests in parallel on the same channel.

Flow control. Pushback at client for large messages (TODO: fix name)

Status: TODO

This test verifies that a client sending faster than a server can drain sees pushback (i.e., attempts to send succeed only after appropriate delays).

TODO Tests

High priority:

Propagation of status code and message (yangg)

Multiple thousand simultaneous calls on same Channel (ctiller)

Metadata: client headers, server headers + trailers, binary+ascii

Normal priority:

Cancel before start (ctiller)

Cancel after sent first message (ctiller)

Cancel after received headers (ctiller)

Timeout but completed before expire (zhaoq)

Multiple thousand simultaneous calls timeout on same Channel (ctiller)

Lower priority:

Flow control. Pushback at client for large messages (abhishek)

Flow control. Pushback at server for large messages (abhishek)

Going over max concurrent streams doesn't fail (client controls itself) (abhishek)

RPC method not implemented (yangg)

Multiple thousand simultaneous calls on different Channels (ctiller)

Failed TLS hostname verification (ejona?)

Large amount of headers to cause CONTINUATIONs; 63K of 'X's, all in one header.

To priorize:

Start streaming RPC but don't send any requests, server responds

Postponed Tests

Resilience to buggy servers: These tests would verify that a client application isn't affected negatively by the responses put on the wire by a buggy server (e.g. the client library won't make the application crash).

Reconnect after transport failure

Reconnect backoff

Fuzz testing

Server

Servers implement various named features for clients to test with. Server features are orthogonal. If a server implements a feature, it is always available for clients. Names are simple descriptions for developer communication and tracking.

Servers should accept these arguments:

• --port=PORT

  • The port to listen on. For example, "8080"

• --use_tls=BOOLEAN

  • Whether to use a plaintext or encrypted connection

Servers must support TLS with ALPN. They should use server1.pem for their certificate.

EmptyCall

Server implements EmptyCall which immediately returns the empty message.

UnaryCall

Server implements UnaryCall which immediately returns a SimpleResponse with a payload body of size SimpleRequest.response_size bytes and type as appropriate for the SimpleRequest.response_type. If the server does not support the response_type, then it should fail the RPC with INVALID_ARGUMENT.

StreamingInputCall

Server implements StreamingInputCall which upon half close immediately returns a StreamingInputCallResponse where aggregated_payload_size is the sum of all request payload bodies received.

StreamingOutputCall

Server implements StreamingOutputCall by replying, in order, with one StreamingOutputCallResponses for each ResponseParameters in StreamingOutputCallRequest. Each StreamingOutputCallResponses should have a payload body of size ResponseParameters.size bytes, as specified by its respective ResponseParameters. After sending all responses, it closes with OK.

FullDuplexCall

Server implements FullDuplexCall by replying, in order, with one StreamingOutputCallResponses for each ResponseParameters in each StreamingOutputCallRequest. Each StreamingOutputCallResponses should have a payload body of size ResponseParameters.size bytes, as specified by its respective ResponseParameters. After receiving half close and sending all responses, it closes with OK.

Compressable Payload

When the client requests COMPRESSABLE payload, the response includes a payload of the size requested containing all zeros and the payload type is COMPRESSABLE.

Observe ResponseParameters.interval_us

In StreamingOutputCall and FullDuplexCall, server delays sending a StreamingOutputCallResponse by the ResponseParameters's interval_us for that particular response, relative to the last response sent. That is, interval_us acts like a sleep before sending the response and accumulates from one response to the next.

Interaction with flow control is unspecified.

Echo Auth Information

Status: Pending

Echo Authenticated Username

If a SimpleRequest has fill_username=true and that request was successfully authenticated, then the SimpleResponse should have username filled with the canonical form of the authenticated source. The canonical form is dependent on the authentication method, but is likely to be a base 10 integer identifier or an email address.

Echo OAuth scope

If a SimpleRequest has fill_oauth_scope=true and that request was successfully authenticated via OAuth, then the SimpleResponse should have oauth_scope filled with the scope of the method being invoked.

Although a general server-side feature, most test servers won't implement this feature. The TLS server grpc-test.sandbox.google.com:443 supports this feature. It requires at least the OAuth scope https://www.googleapis.com/auth/xapi.zoo for authentication to succeed.

Discussion:

Ideally, this would be communicated via metadata and not in the request/response, but we want to use this test in code paths that don't yet fully communicate metadata.