#LynxService API

#Introduction

Lynx Service provides Lynx Engine with host-specific capabilities, including image, log, and FetchAPI capabilities. Different hosts have specific requirements for their own image, log, and network libraries, so Lynx Engine opens up autonomous access capabilities for such scenarios through the LynxService API.

#Overall Design

Lynx Engine and Lynx Service adopt a dependency-separation design. In terms of the dependency relationship, Lynx Service depends on the LynxService API provided by Lynx Engine to implement itself, while Lynx Engine does not depend on LynxService. At runtime, Lynx Engine will search for the registered Lynx Service through the service lookup mechanism and call it via the LynxService API.

#LynxService API

The LynxService API is provided by Lynx Engine and is designed to specify the capabilities of LynxService. Lynx Service needs to correctly implement itself in accordance with the requirements of the LynxService API to ensure that Lynx Engine can properly use this basic capability.

#1. Quick Access

Lynx provides a default implementation of Lynx Service, which can be directly accessed

#2. Lynx Service Customization

If there are custom requirements, you can also quickly implement and register relevant content according to your own needs. The following will take log service as an example to introduce how to implement and register a custom Lynx Service:

#import <Lynx/LynxService.h>
#import <Lynx/LynxServiceLogProtocol.h>

// Implement LynxServiceLogProtocol
@interface YourLogService : NSObject <LynxServiceLogProtocol>
@end

#import "YourLogService.h"

[[maybe_unused]] void logWrite(unsigned int level, const char *tag, const char *format) {
  if (format == NULL) {
    return;
  }
  NSLog(@"[%s] %s", tag == NULL ? "" : tag, format);
}

// Use the LynxServiceRegister macro to achieve automatic registration
@LynxServiceRegister(LynxLogService);

// Implement LynxLogService
@implementation LynxLogService

// Irrelevant property, will be removed later
+ (NSString*)serviceBizID {
  return DEFAULT_LYNX_SERVICE;
}

// Irrelevant property, will be removed later
+ (LynxServiceScope)serviceScope {
  return LynxServiceScopeDefault;
}

// Return the corresponding service type for runtime lookup
+ (NSUInteger)serviceType {
  return kLynxServiceLog;
}

// Recommended: Implement as a singleton
+ (instancetype)sharedInstance {
  static dispatch_once_t onceToken;
  static YourLogService *logService;
  dispatch_once(&onceToken, ^{
    logService = [[YourLogService alloc] init];
  });
  return logService;
}

// Implement all the interfaces required by LynxServiceLogProtocol
- (void *)getWriteFunction {
  return (void *)logWrite;
}

@end

object YourLogService : ILynxLogService {
  private var logOutputChannel: LogOutputChannelType = LogOutputChannelType.Platform

  override fun logByPlatform(
    level: Int,
    tag: String,
    msg: String,
  ) {
    // Implemention
  }

  override fun isLogOutputByPlatform(): Boolean = logOutputChannel == LogOutputChannelType.Platform

  override fun getDefaultWriteFunction(): Long = 0

  override fun switchLogToSystem(enableSystemLog: Boolean) {}

  override fun getLogToSystemStatus(): Boolean = false
}

import { ILynxLogService } from '@lynx/lynx';

export class YourLogService implements ILynxLogService {
  static instance = new YourLogService();

  logByPlatform(level: number, tag: string, message: string): void {
    console.log(`level: ${level} tag: ${tag} message: ${message}`);
  }

  isLogOutputByPlatform(): boolean {
    return true;
  }

  getDefaultWriteFunction(): number {
    return 0;
  }
}

pod 'LynxService', '3.4.1', :subspecs => [
      'Image',
-     'Log',
      'Http',
  ]

- LynxServiceCenter.inst().registerService(ILynxLogService::class.java, LynxLogService)
+ LynxServiceCenter.inst().registerService(ILynxLogService::class.java, YourLogService)

dependencies {
-   // integrating log-service
-   implementation "engineer.lynx.test2:lynx-service-log:0.0.1"
}

- LynxServiceCenter.registerService(LynxServiceType.Log, LynxLogService.instance);
+ LynxServiceCenter.registerService(LynxServiceType.Log, YourLogService.instance);

"dependencies": {
- "@lynx/lynx_log_service": "0.0.1",
}