Case
aiosendspin -> sendspin-jvm
Start the server first, then the client. The client connects, advertises PCM then FLAC, and the server starts streaming the preferred PCM format. The client then emits stream/request-format asking for FLAC, the server re-emits stream/start with the FLAC format, and the matrix verifies the client observed the renegotiated FLAC stream.
Server
aiosendspin
Client
sendspin-jvm
Status
Passed
Renegotiated pcm/8000Hz/16bit/1ch -> flac/8000Hz/16bit/1ch
Inspection
Summaries, logs, and builds
Matrix result
RAW{
"case_dir": "artifacts/results/data/macos__client-initiated-request-format-flac__aiosendspin__to__sendspin-jvm",
"client_exit_code": 0,
"client_impl": "sendspin-jvm",
"reason": "Renegotiated pcm/8000Hz/16bit/1ch -> flac/8000Hz/16bit/1ch",
"scenario_id": "client-initiated-request-format-flac",
"server_exit_code": 0,
"server_impl": "aiosendspin",
"status": "passed"
}Server summary (JSON)
RAW{
"audio": {
"bit_depth": 16,
"channels": 1,
"clip_seconds": 5.0,
"duration_seconds": 5.0,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_alignment_samples": null,
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 72,
"sent_codec_header_sha256": "cf785f756a60586c95243e827c384663e8dc4be893f3eb79a5b092b4df511214",
"sent_encoded_byte_count": 5382,
"sent_encoded_sha256": "ba1d2a93f75a32b11169ea4eaff0e2dbed15e24ec444dfa39157ac29607bf2f0",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "9d447b5b270bc99b45bb9a616937e436c941ca56c477f9cbe16a93275a6b059e",
"trimmed_source_frames": 0
},
"client": {
"active_roles": [
"player@v1",
"controller@v1",
"metadata@v1",
"artwork@v1",
"color@v1"
],
"client_id": "sendspin-jvm-client-id",
"name": "sendspin-jvm-client",
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
]
},
"discovery_method": "registry_advertised",
"implementation": "aiosendspin",
"initiator_role": "client",
"peer_hello": {
"payload": {
"artwork@v1_support": {
"channels": [
{
"format": "jpeg",
"media_height": 256,
"media_width": 256,
"source": "album"
}
]
},
"client_id": "sendspin-jvm-client-id",
"device_info": {
"manufacturer": "conformance",
"product_name": "conformance-client",
"software_version": "1.0"
},
"name": "sendspin-jvm-client",
"player@v1_support": {
"buffer_capacity": 262144,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 16,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
}
]
},
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
],
"trust_level": "none",
"unpaired_access": {
"enabled": false
},
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "pcm",
"role": "server",
"scenario_id": "client-initiated-request-format-flac",
"server_id": "VopqfEk3ow-jOt6UB7U5ox7l9-9BW0ZVwR_g_yTJVms",
"server_name": "aiosendspin server",
"status": "ok",
"stream": {
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAAAASVAfQA8AAAAAAAAAAAAAAAAAAAAAAAAAAA",
"codec_header_sha256": "cf785f756a60586c95243e827c384663e8dc4be893f3eb79a5b092b4df511214",
"sample_rate": 8000
}
}Server log
RAWINFO:aiosendspin.server.server:Starting Sendspin server on port 19060
INFO:aiosendspin.server.server:Sendspin server started successfully on 127.0.0.1:19060
WARNING:aiosendspin.server.server:No IP addresses available for mDNS advertising. Clients may not be able to discover this server. Consider specifying addresses manually via advertise_addresses.
WARNING:aiosendspin.server.connection.unknown-127.0.0.1:Accepting unencrypted legacy connection (transition mode)
WARNING:aiosendspin.server.connection.sendspin-jvm-client-id:Late binary type=4 role=player: skipping 1 chunk(s); late_by_us=9199 ts_us=1095407332 now_us=1095416531 queue=2/8192
WARNING:aiosendspin.server.connection.sendspin-jvm-client-id:Late binary type=4 role=player: skipping 7 chunk(s); late_by_us=59063 ts_us=1096415332 now_us=1096474395 queue=2/8192
{
"audio": {
"bit_depth": 16,
"channels": 1,
"clip_seconds": 5.0,
"duration_seconds": 5.0,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_alignment_samples": null,
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 72,
"sent_codec_header_sha256": "cf785f756a60586c95243e827c384663e8dc4be893f3eb79a5b092b4df511214",
"sent_encoded_byte_count": 5382,
"sent_encoded_sha256": "ba1d2a93f75a32b11169ea4eaff0e2dbed15e24ec444dfa39157ac29607bf2f0",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "9d447b5b270bc99b45bb9a616937e436c941ca56c477f9cbe16a93275a6b059e",
"trimmed_source_frames": 0
},
"client": {
"active_roles": [
"player@v1",
"controller@v1",
"metadata@v1",
"artwork@v1",
"color@v1"
],
"client_id": "sendspin-jvm-client-id",
"name": "sendspin-jvm-client",
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
]
},
"discovery_method": "registry_advertised",
"implementation": "aiosendspin",
"initiator_role": "client",
"peer_hello": {
"payload": {
"artwork@v1_support": {
"channels": [
{
"format": "jpeg",
"media_height": 256,
"media_width": 256,
"source": "album"
}
]
},
"client_id": "sendspin-jvm-client-id",
"device_info": {
"manufacturer": "conformance",
"product_name": "conformance-client",
"software_version": "1.0"
},
"name": "sendspin-jvm-client",
"player@v1_support": {
"buffer_capacity": 262144,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 16,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
}
]
},
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
],
"trust_level": "none",
"unpaired_access": {
"enabled": false
},
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "pcm",
"role": "server",
"scenario_id": "client-initiated-request-format-flac",
"server_id": "VopqfEk3ow-jOt6UB7U5ox7l9-9BW0ZVwR_g_yTJVms",
"server_name": "aiosendspin server",
"status": "ok",
"stream": {
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAAAASVAfQA8AAAAAAAAAAAAAAAAAAAAAAAAAAA",
"codec_header_sha256": "cf785f756a60586c95243e827c384663e8dc4be893f3eb79a5b092b4df511214",
"sample_rate": 8000
}
}
WARNING:root:server.close() timed out after 5s; continuing shutdown
ERROR:asyncio:Unclosed client session
client_session: <aiohttp.client.ClientSession object at 0x107fd7e60>
Client summary (JSON)
RAW{
"client_id": "sendspin-jvm-client-id",
"client_name": "sendspin-jvm-client",
"implementation": "sendspin-jvm",
"initiator_role": "client",
"peer_hello": {
"active_roles": [
"player@v1",
"controller@v1",
"metadata@v1",
"artwork@v1",
"color@v1"
],
"connection_reason": "discovery",
"name": "aiosendspin server",
"server_id": "VopqfEk3ow-jOt6UB7U5ox7l9-9BW0ZVwR_g_yTJVms",
"version": 1
},
"preferred_codec": "pcm",
"renegotiation": {
"final_format": {
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
"initial_format": {
"bit_depth": 16,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
},
"requested": {
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
"stream_start_count": 2
},
"role": "client",
"scenario_id": "client-initiated-request-format-flac",
"server": null,
"status": "ok"
}Client log
RAWJul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: connecting to ws://127.0.0.1:19060/sendspin
Jul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: WebSocket open
Jul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: server hello from 'aiosendspin server' reason=discovery
Jul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: stream/start codec=pcm
Jul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: first audio chunk — ts=1092067332 size=400 bufferSize=0
Jul 21, 2026 5:31:55 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: stream/start codec=flac
Jul 21, 2026 5:32:01 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: closing (1000 )
Jul 21, 2026 5:32:01 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: closed (1000 )
{
"server": null,
"initiator_role": "client",
"role": "client",
"preferred_codec": "pcm",
"peer_hello": {
"active_roles": [
"player@v1",
"controller@v1",
"metadata@v1",
"artwork@v1",
"color@v1"
],
"name": "aiosendspin server",
"connection_reason": "discovery",
"server_id": "VopqfEk3ow-jOt6UB7U5ox7l9-9BW0ZVwR_g_yTJVms",
"version": 1
},
"implementation": "sendspin-jvm",
"renegotiation": {
"final_format": {
"codec": "flac",
"sample_rate": 8000,
"channels": 1,
"bit_depth": 16
},
"requested": {
"codec": "flac",
"channels": 1,
"sample_rate": 8000,
"bit_depth": 16
},
"stream_start_count": 2,
"initial_format": {
"codec": "pcm",
"sample_rate": 8000,
"channels": 1,
"bit_depth": 16
}
},
"client_name": "sendspin-jvm-client",
"client_id": "sendspin-jvm-client-id",
"scenario_id": "client-initiated-request-format-flac",
"status": "ok"
}
Server build log · python-adapters · built · 0.20s
RAWListing 'src'... Listing 'src/conformance'... Listing 'src/conformance/adapters'... Compiling 'src/conformance/adapters/__init__.py'... Compiling 'src/conformance/adapters/aiosendspin_client.py'... Compiling 'src/conformance/adapters/aiosendspin_server.py'... Compiling 'src/conformance/adapters/placeholder.py'... Compiling 'src/conformance/adapters/sendspin_jvm_client.py'... Compiling 'src/conformance/cli.py'... Compiling 'src/conformance/merge.py'... Compiling 'src/conformance/registry.py'... Listing 'src/sendspin_conformance.egg-info'... Listing 'scripts'... Compiling 'scripts/detect_regressions.py'... Compiling 'scripts/merge_results.py'... Compiling 'scripts/run_all.py'... Compiling 'scripts/setup_repositories.py'... Compiling 'scripts/setup_workspace.py'...
Client build log · sendspin-jvm-client · built · 91.75s
RAWDownloading https://services.gradle.org/distributions/gradle-9.4.1-bin.zip .............10%.............20%.............30%.............40%.............50%.............60%..............70%.............80%.............90%.............100% Welcome to Gradle 9.4.1! Here are the highlights of this release: - Java 26 support - Non-class-based JVM tests - Enhanced console progress bar For more details see https://docs.gradle.org/9.4.1/release-notes.html Starting a Gradle Daemon (subsequent builds will be faster) > Task :checkKotlinGradlePluginConfigurationErrors SKIPPED > Task :sendspin-protocol:checkKotlinGradlePluginConfigurationErrors SKIPPED > Task :processResources NO-SOURCE > Task :sendspin-protocol:kspKotlin > Task :sendspin-protocol:processResources > Task :sendspin-protocol:compileKotlin > Task :sendspin-protocol:compileJava NO-SOURCE > Task :sendspin-protocol:classes > Task :sendspin-protocol:jar > Task :compileKotlin > Task :compileJava NO-SOURCE > Task :classes UP-TO-DATE > Task :jar [Incubating] Problems report is available at: file:///Users/runner/work/conformance/conformance/adapters/sendspin-jvm/client/build/reports/problems/problems-report.html Deprecated Gradle features were used in this build, making it incompatible with Gradle 10. You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins. For more on this, please refer to https://docs.gradle.org/9.4.1/userguide/command_line_interface.html#sec:command_line_warnings in the Gradle documentation. BUILD SUCCESSFUL in 1m 29s 6 actionable tasks: 6 executed Consider enabling configuration cache to speed up this build: https://docs.gradle.org/9.4.1/userguide/configuration_cache_enabling.html