Version Checking System

Client/server version comparison using git hashes at connection time.

Architecture

[Client: LoginScene] ←TCP→ [TCPAuthServer]
        ↓                        ↓
  Version.hpp            VersionHistoryManager
  (getClientVersion)      (loadFromFile)
        ↓                        ↓
   VersionInfo    ←────→   VersionHistory
   (13 bytes)              (451 bytes)

Wire Structures

// VersionInfo (13 bytes) - Sent in AuthResponseWithToken
struct VersionInfo {
    uint8_t major, minor, patch;
    uint8_t flags;              // Bit 0: isDev
    char gitHash[9];            // 8 chars + null
};

// VersionHistory (451 bytes) - Last 50 commits
struct VersionHistory {
    uint8_t count;
    char hashes[50][9];         // Newest first
};

Verification Flow

1. Login - Client sends credentials
2. Auth Success - Server responds with serverVersion + versionHistory
3. Client compares - isVersionCompatible(client, server)
4. If mismatch - Popup shows commits behind + JENKINS button

Version Compatibility

The client performs an exact hash match with the server version:

// Version.hpp - Actual implementation
inline bool isVersionCompatible(const VersionInfo& client, const VersionInfo& server) {
    if (client.isDev()) {
        return true;  // Dev mode bypasses check
    }
    return client.isExactMatch(server);  // Exact hash comparison
}

The history is used separately to calculate how many commits behind:

// TCPClient.cpp - After receiving auth response
int commitsBehind = response.versionHistory.findPosition(clientVersion.gitHash);
if (!isVersionCompatible(clientVersion, response.serverVersion)) {
    emit(TCPVersionMismatchEvent{clientVersion, response.serverVersion, commitsBehind});
}

Development Mode

Create a version.dev file at project root to bypass version checking:

touch version.dev    # Activates dev mode (gitignored)

In dev mode: - Version mismatch warnings are suppressed - Useful for local development against production server

Test Environment Variable

Simulate a different git hash for testing:

RTYPE_TEST_HASH=abc1234 ./rtype_client

Key Files

File	Description
src/client/include/core/Version.hpp	getClientVersion(), isDevMode(), formatVersion()
src/server/include/infrastructure/version/VersionHistoryManager.hpp	Singleton, loadFromFile(), getCommitsBehind()
src/common/protocol/Protocol.hpp	VersionInfo, VersionHistory structs
src/client/src/scenes/LoginScene.cpp	Mismatch popup, JENKINS button
scripts/generate_version_history.sh	Helper script to generate history

CI/CD Integration

Jenkinsfile

Generates version_history.txt at checkout:

stage('Checkout') {
    steps {
        checkout scm
        sh 'git log --format="%h" -n 50 > version_history.txt'
    }
}

deploy-service.py

Regenerates history at each VPS deployment:

def generate_version_history():
    result = subprocess.run(
        ['git', 'log', '--format=%h', '-n', '50'],
        capture_output=True, text=True
    )
    with open('version_history.txt', 'w') as f:
        f.write(result.stdout)

Version History File Format

Simple text file with one short hash per line (newest first):

f9dbaad
11d8c82
3a4d4c6
674b1c7
32120ac
...

The server loads this file at startup via VersionHistoryManager::loadFromFile().

Client Mismatch UI

When version mismatch is detected:

1. Warning popup displays:
2. "Version mismatch detected"
3. Number of commits behind (if calculable)

4. Current client hash vs server hash

5. Actions available:

6. JENKINS button - Opens CI/CD to download latest build
7. CONTINUE button - Proceed anyway (may cause issues)
8. QUIT button - Exit client

Troubleshooting

"Version mismatch" on every connection

1. Rebuild client from latest main branch
2. Check if version.dev exists (should bypass)
3. Verify server's version_history.txt is up to date

Client shows wrong hash

1. Ensure clean git state (git status)
2. Check RTYPE_TEST_HASH env var isn't set
3. Rebuild client after git pull

Server history not loading

1. Check version_history.txt exists in server directory
2. Verify file permissions
3. Check server logs for load errors