Case
sendspin-go -> sendspin-jvm
Start the server first, then the client. The server loads the PCM audio derived from almost_silent.flac, the client advertises a listener and FLAC as its only supported audio format, the server connects in, uses the SDK to encode the PCM into FLAC, streams it to the client, and the matrix compares the transported FLAC header and chunk bytes as received by the client.
Server
sendspin-go
Client
sendspin-jvm
Status
Passed
FLAC header and chunk bytes match exactly
Inspection
Summaries, logs, and builds
Matrix result
RAW{
"case_dir": "artifacts/results/data/macos__server-initiated-flac__sendspin-go__to__sendspin-jvm",
"client_exit_code": 0,
"client_impl": "sendspin-jvm",
"reason": "FLAC header and chunk bytes match exactly",
"scenario_id": "server-initiated-flac",
"server_exit_code": 0,
"server_impl": "sendspin-go",
"status": "passed"
}Server summary (JSON)
RAW{
"audio": {
"bit_depth": 24,
"channels": 1,
"clip_seconds": 5,
"duration_seconds": 5,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 1,
"sent_codec_header_sha256": "f7c0c5cea7e7afcc5cad7f40b3c292c811132bd60d65f8a55c383722ce6c1edb",
"sent_encoded_byte_count": 14698,
"sent_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "f9ae8fe5e6c34fc6baa67cbb4a97224d777a0bfacf6d996449be1054824f66bf"
},
"client": {
"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": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"artwork@v1_support": {
"channels": [
{
"format": "jpeg",
"media_height": 256,
"media_width": 256,
"source": "album"
}
]
},
"client_id": "sendspin-jvm-client-id",
"color@v1_support": {},
"controller@v1_support": {},
"device_info": {
"manufacturer": "conformance",
"product_name": "conformance-client",
"software_version": "1.0"
},
"metadata@v1_support": {},
"name": "sendspin-jvm-client",
"player@v1_support": {
"buffer_capacity": 262144,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 2,
"codec": "flac",
"sample_rate": 48000
}
]
},
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
],
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "flac",
"role": "server",
"scenario_id": "server-initiated-flac",
"server_id": "sendspin-go-server",
"server_name": "sendspin-go server",
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}Server log
RAW{
"audio": {
"bit_depth": 24,
"channels": 1,
"clip_seconds": 5,
"duration_seconds": 5,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 1,
"sent_codec_header_sha256": "f7c0c5cea7e7afcc5cad7f40b3c292c811132bd60d65f8a55c383722ce6c1edb",
"sent_encoded_byte_count": 14698,
"sent_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "f9ae8fe5e6c34fc6baa67cbb4a97224d777a0bfacf6d996449be1054824f66bf"
},
"client": {
"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": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"artwork@v1_support": {
"channels": [
{
"format": "jpeg",
"media_height": 256,
"media_width": 256,
"source": "album"
}
]
},
"client_id": "sendspin-jvm-client-id",
"color@v1_support": {},
"controller@v1_support": {},
"device_info": {
"manufacturer": "conformance",
"product_name": "conformance-client",
"software_version": "1.0"
},
"metadata@v1_support": {},
"name": "sendspin-jvm-client",
"player@v1_support": {
"buffer_capacity": 262144,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 2,
"codec": "flac",
"sample_rate": 48000
}
]
},
"supported_roles": [
"player@v1",
"metadata@v1",
"artwork@v1",
"controller@v1",
"color@v1"
],
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "flac",
"role": "server",
"scenario_id": "server-initiated-flac",
"server_id": "sendspin-go-server",
"server_name": "sendspin-go server",
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}
Client summary (JSON)
RAW{
"audio": {
"audio_chunk_count": 1,
"received_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"received_pcm_sha256": null,
"received_sample_count": 4899
},
"client_id": "sendspin-jvm-client-id",
"client_name": "sendspin-jvm-client",
"implementation": "sendspin-jvm",
"initiator_role": "server",
"peer_hello": {
"active_roles": [
"player@v1",
"metadata@v1"
],
"connection_reason": "playback",
"name": "sendspin-go server",
"server_id": "sendspin-go-server",
"version": 1
},
"preferred_codec": "flac",
"role": "client",
"scenario_id": "server-initiated-flac",
"server": null,
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}Client log
RAWSLF4J: No SLF4J providers were found.
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See https://www.slf4j.org/codes.html#noProviders for further details.
Jul 21, 2026 5:30:58 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinServerHost: listening on port 20020
Jul 21, 2026 5:30:58 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinServerHost: incoming connection from /127.0.0.1:49427
Jul 21, 2026 5:30:58 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinServerHost: activating server 'sendspin-go server' (id=sendspin-go-server reason=playback)
Jul 21, 2026 5:30:58 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: server hello from 'sendspin-go server' reason=playback
Jul 21, 2026 5:30:58 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: stream/start codec=flac
Jul 21, 2026 5:30:59 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: server/state title='Almost Silent'
Jul 21, 2026 5:30:59 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: first audio chunk — ts=1992503 size=14698 bufferSize=0
Jul 21, 2026 5:30:59 AM com.sendspin.protocol.ProtocolLog w
WARNING: AudioBuffer: dropped late chunk (1033619.9 ms late)
Jul 21, 2026 5:30:59 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinServerHost: connection closed (1000 done)
Jul 21, 2026 5:30:59 AM com.sendspin.protocol.ProtocolLog i
INFO: SendSpinClient: server socket closed (1000 done)
{
"server": null,
"initiator_role": "server",
"role": "client",
"preferred_codec": "flac",
"stream": {
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000,
"channels": 1,
"bit_depth": 24
},
"peer_hello": {
"active_roles": [
"player@v1",
"metadata@v1"
],
"name": "sendspin-go server",
"connection_reason": "playback",
"server_id": "sendspin-go-server",
"version": 1
},
"implementation": "sendspin-jvm",
"audio": {
"audio_chunk_count": 1,
"received_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"received_pcm_sha256": null,
"received_sample_count": 4899
},
"client_name": "sendspin-jvm-client",
"client_id": "sendspin-jvm-client-id",
"scenario_id": "server-initiated-flac",
"status": "ok"
}
Server build log · sendspin-go-server · built · 0.73s
RAWNo build detail was recorded.
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