feat: replace gRPC transport with FIBP binary protocol

[vieiralucas]

Summary

• Replaces the gRPC/protobuf transport with FIBP (Fila Binary Protocol) over raw TCP/TLS
• Removes all gRPC and protobuf dependencies from build.gradle (no runtime dependencies remain)
• Adds FibpConnection — TCP socket with length-prefixed framing, handshake, correlation-ID multiplexing via ConcurrentHashMap + CompletableFuture, heartbeat scheduler, and optional TLS via SSLSocket
• Adds FibpCodec — wire encoding/decoding matching fila-core/src/fibp/wire.rs exactly (enqueue, consume push batch, ack, nack, error frames)
• Keeps the public FilaClient API identical: enqueue, enqueueMany, consume, ack, nack, close, Builder with all TLS/auth/batch options preserved
• Batcher groups messages by queue before sending (one FIBP enqueue frame per queue name, since the frame-level field is per-queue)
• RpcException.Code replaces io.grpc.Status.Code; error classification uses keyword matching on plain-text error payloads (matching the Rust SDK pattern)
• AUTH uses raw key bytes in OP_AUTH frame (no length prefix, matching server protocol)
• Consume push frames decoded as batches (msg_count:u16 | messages...)
• FibpAdminClient added to test package with hand-rolled minimal protobuf for CreateQueueRequest (avoids a test protobuf dependency)
• Integration tests (FilaClientTest, BatchClientTest, TlsAuthClientTest) guarded by @EnabledIf("serverAvailable") and skip cleanly when no binary is present; unit tests all pass

Test plan

• All 21 unit tests pass (./gradlew test)
• spotlessCheck passes (formatting enforced by Google Java Format)
• CI integration tests pass against downloaded fila-server binary
• TLS tests: verify withTls(), withTlsCaCert(), withTlsClientCert() (mTLS) all connect
• Auth tests: verify withApiKey() sends AUTH frame and server accepts/rejects correctly

🤖 Generated with Claude Code

---

Summary by cubic

Replaced the gRPC/protobuf transport with FIBP (Fila Binary Protocol) over raw TCP/TLS while keeping the public FilaClient API the same. This removes all gRPC/protobuf deps, adds a single-socket multiplexed connection with heartbeat and AUTH, and includes stability/validation fixes.

• New Features

  • Added FibpConnection: framing, handshake, correlation IDs, heartbeat scheduler, optional TLS, and AUTH via OP_AUTH.
  • Added FibpCodec: encode/decode for enqueue, batched consume push, ack/nack, and error frames; validates header count (<=255) and str16 length (<=65535).
  • Public FilaClient API unchanged; batcher groups messages by queue and sends one enqueue frame per queue; enqueueMany enforces a single target queue.
  • Replaced gRPC status with RpcException.Code; errors mapped from server error text.
  • Robustness: remove pending futures on consume timeout/interrupt; guard push handler exceptions to keep the reader thread alive; map batch timeouts to UNAVAILABLE; add a fallback catch in the batcher to resolve futures with INTERNAL on unexpected exceptions.
  • Tests use FibpAdminClient for queue creation (supports TLS/mTLS); README updated; version bumped to 0.3.0.

• Migration

  • Update dependency to dev.faisca:fila-client:0.3.0.
  • Replace any uses of gRPC Status.Code with RpcException.Code.
  • build() now opens a connection; tests that constructed clients without a running server should guard or defer client creation.
  • Consume handlers run on the FIBP reader thread; avoid heavy or blocking work in the callback.
  • enqueueMany should target a single queue per call.

^{Written for commit 03bf792. Summary will update on new commits.}

[cubic-dev-ai]

7 issues found across 17 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/main/java/dev/faisca/fila/FibpConnection.java">

<violation number="1" location="src/main/java/dev/faisca/fila/FibpConnection.java:191">
P2: Remove the pending entry when the consume setup times out or is interrupted; otherwise the failed consume leaves a stale future in the pending map.</violation>

<violation number="2" location="src/main/java/dev/faisca/fila/FibpConnection.java:328">
P2: Guard push handlers so an exception doesn’t kill the reader thread and strand pending requests.</violation>
</file>

<file name="src/main/java/dev/faisca/fila/FibpCodec.java">

<violation number="1" location="src/main/java/dev/faisca/fila/FibpCodec.java:73">
P2: Guard the header count before writing the u8 field. Counts >255 wrap in writeByte and desynchronize the frame.</violation>

<violation number="2" location="src/main/java/dev/faisca/fila/FibpCodec.java:311">
P2: Validate str16 lengths before writing. Without a bounds check, strings longer than 65,535 bytes wrap in writeShort and corrupt the frame.</violation>
</file>

<file name="src/main/java/dev/faisca/fila/FilaClient.java">

<violation number="1" location="src/main/java/dev/faisca/fila/FilaClient.java:112">
P2: enqueueMany does not enforce that all messages target the same queue even though the FIBP frame encodes only the first queue name. Mixed-queue batches will silently send messages to the wrong queue.</violation>
</file>

<file name="src/test/java/dev/faisca/fila/TestServer.java">

<violation number="1" location="src/test/java/dev/faisca/fila/TestServer.java:88">
P2: createQueueWithApiKey now connects over a plain Socket via FibpAdminClient, but it is used immediately after startWithTls. This skips TLS/mTLS setup, so queue creation will fail against a TLS-enabled server.</violation>
</file>

<file name="src/main/java/dev/faisca/fila/Batcher.java">

<violation number="1" location="src/main/java/dev/faisca/fila/Batcher.java:239">
P2: respFuture.get can throw InterruptedException/TimeoutException, but the generic catch maps them to INTERNAL and clears the interrupt. Handle these explicitly (restore interrupt + map timeout to UNAVAILABLE) so batched enqueue errors match sendSync behavior.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

1 issue found across 6 files (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/main/java/dev/faisca/fila/Batcher.java">

<violation number="1" location="src/main/java/dev/faisca/fila/Batcher.java:244">
P2: The generic catch-all was removed, so unexpected runtime exceptions (e.g., decodeEnqueueResponse failures) will now escape this method and leave the per-item futures unresolved. Add a fallback catch to map and complete all futures on any other exception.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}