everything complete

console-api/src/update/update.controller.ts

-import { Controller, Get, Param, Query, Render, ValidationPipe } from '@nestjs/common';
+import { Body, Controller, Get, Param, ParseArrayPipe, Post, Query, Render, ValidationPipe } from '@nestjs/common';
 import { UpdateService } from './update.service';
-import { ApiOkResponse, ApiOperation, ApiParam, ApiProperty, ApiQuery, ApiTags } from '@nestjs/swagger';
+import { ApiBody, ApiOkResponse, ApiOperation, ApiParam, ApiProperty, ApiQuery, ApiTags } from '@nestjs/swagger';
 import { DepotDto } from '../dto/Depot.dto';
 
 @Controller('update')
@@ -42,4 +42,22 @@ export class UpdateController {
   ) {
     return this.updateService.getFullPackageMetalink(id, depot, version);
   }
+
+  @Post('update/:id/:version')
+  @Render('metalinks')
+  @ApiOperation({ summary: '获取 app 部分包 metalink', description: '根据文件返回需要下载什么文件' })
+  @ApiParam({ name: 'id', description: 'APP 的 id' })
+  @ApiParam({ name: 'version', description: 'APP 的版本号' })
+  @ApiQuery({ type: DepotDto, description: 'APP 的类型' })
+  @ApiBody({ type: [String], description: '需要什么文件' })
+  @ApiOkResponse({ type: String })
+  async getPartPackageMetalink(
+    @Param('id') id: string,
+    @Query(new ValidationPipe({ transform: true })) depot: DepotDto,
+    @Param('version') version: string,
+    @Body(new ParseArrayPipe()) requestedFiles: string[]
+  ) {
+    //return requestedFiles;
+    return this.updateService.getPartPackageMetalink(id, depot, version, requestedFiles);
+  }
 }

console-api/src/update/update.service.ts

@@ -5,8 +5,9 @@ import { App } from '../entities/App.entity';
 import { DepotDto } from '../dto/Depot.dto';
 import { Build } from '../entities/Build.entity';
 import { BlankReturnMessageDto } from '../dto/ReturnMessage.dto';
-import { ArchiveType } from '../entities/Archive.entity';
+import { Archive, ArchiveType } from '../entities/Archive.entity';
 import { PackageS3Service } from '../package-s3/package-s3.service';
+import _ from 'lodash';
 
 @Injectable()
 export class UpdateService extends ConsoleLogger {
@@ -24,14 +25,21 @@ export class UpdateService extends ConsoleLogger {
     return (await this.db.getRepository(App).find({ where: { appData: Not(IsNull()), isDeleted: false } })).map((a) => a.appData);
   }
 
-  private async getBuild(id: string, depotDto: DepotDto, version: string, extraQuery?: (query: SelectQueryBuilder<Build>) => void) {
+  private async getBuild(
+    id: string,
+    depotDto: DepotDto,
+    version: string,
+    extraQuery?: (query: SelectQueryBuilder<Build>) => void,
+    noErrorExit = false
+  ) {
     const depotObj = depotDto.toActual;
     const query = this.db
       .getRepository(Build)
       .createQueryBuilder('build')
+      //.select('build.id', 'id')
+      //.addSelect('build.checksum', 'checksum')
       .innerJoin('build.depot', 'depot')
       .innerJoin('depot.app', 'app')
-      .leftJoinAndSelect('build.archives', 'archive')
       .where('app.id = :id', { id })
       .andWhere('app.isDeleted = false')
       .andWhere('depot.platform = :platform')
@@ -43,12 +51,43 @@ export class UpdateService extends ConsoleLogger {
       extraQuery(query);
     }
     const build = await query.getOne();
-    if (!build) {
+    if (!noErrorExit && !build) {
       throw new BlankReturnMessageDto(404, 'Build not found').toException();
     }
     return build;
   }
 
+  private async getArchives(
+    id: string,
+    depotDto: DepotDto,
+    version: string,
+    extraQuery?: (query: SelectQueryBuilder<Archive>) => void,
+    noErrorExit = false
+  ) {
+    const depotObj = depotDto.toActual;
+    const query = this.db
+      .getRepository(Archive)
+      .createQueryBuilder('archive')
+      .innerJoin('archive.build', 'build')
+      .innerJoin('build.depot', 'depot')
+      .innerJoin('depot.app', 'app')
+      .where('app.id = :id', { id })
+      .andWhere('app.isDeleted = false')
+      .andWhere('depot.platform = :platform')
+      .andWhere('depot.arch = :arch')
+      .andWhere('depot.locale = :locale')
+      .andWhere('build.version = :version', { version })
+      .setParameters(depotObj);
+    if (extraQuery) {
+      extraQuery(query);
+    }
+    const archives = await query.getMany();
+    if (!noErrorExit && !archives.length) {
+      throw new BlankReturnMessageDto(404, 'Build not found').toException();
+    }
+    return archives;
+  }
+
   async getChecksum(id: string, depotDto: DepotDto, version: string) {
     const build = await this.getBuild(id, depotDto, version);
     return {
@@ -59,12 +98,83 @@ export class UpdateService extends ConsoleLogger {
   }
 
   async getFullPackageMetalink(id: string, depotDto: DepotDto, version: string) {
-    const build = await this.getBuild(id, depotDto, version, (qb) =>
+    const archives = await this.getArchives(id, depotDto, version, (qb) =>
       qb.andWhere('archive.role = :fullRole', { fullRole: ArchiveType.Full })
     );
     return {
       cdnUrl: this.cdnUrl,
-      archives: build.archives,
+      archives: archives,
+    };
+  }
+
+  private getPartArchiveSubset(
+    requestedFiles: string[],
+    allArchives: Archive[],
+    currentSize = 0,
+    currentBestSolutionValue = Infinity
+  ): [Archive[], number] {
+    /*
+    this.log(
+      `requested: ${requestedFiles.join(',')} remaining: ${allArchives
+        .map((a) => `${a.size}:${a.files.join(',')}`)
+        .join('|')} currentSize: ${currentSize} currentBestSolutionValue: ${currentBestSolutionValue}`
+    );
+     */
+    if (!requestedFiles.length) {
+      return [[], currentSize];
+    }
+    let bestSolution: [Archive[], number] = [null, currentBestSolutionValue];
+    for (let i = 0; i < allArchives.length; ++i) {
+      const archive = allArchives[i];
+      const nextStepSize = currentSize + archive.size;
+      if (nextStepSize > bestSolution[1]) {
+        // 加一个包就太大了的话，不考虑这个方案了
+        continue;
+      }
+      const remainingFiles = _.difference(requestedFiles, archive.files);
+      const remainingArchives = allArchives.slice(i + 1);
+      const nextStepResult = this.getPartArchiveSubset(remainingFiles, remainingArchives, nextStepSize, bestSolution[1]);
+      if (nextStepResult[0] !== null && nextStepResult[1] < bestSolution[1]) {
+        nextStepResult[0].push(archive);
+        bestSolution = nextStepResult;
+        // this.log(`Got better: ${nextStepResult[0].map((a) => `${a.size}:${a.files.join(',')}`).join('|')} ${nextStepResult[1]}`);
+      }
+    }
+    return bestSolution;
+  }
+
+  async getPartPackageMetalink(id: string, depotDto: DepotDto, version: string, requestedFiles: string[]) {
+    const tryExactArchives = await this.getArchives(
+      id,
+      depotDto,
+      version,
+      (qb) =>
+        qb
+          .andWhere('archive.role = :updateRole', { updateRole: ArchiveType.Update })
+          .andWhere(':requestedFiles = archive.files', { requestedFiles: requestedFiles })
+          .orderBy('archive.size', 'ASC')
+          .limit(1),
+      true
+    );
+    if (tryExactArchives.length) {
+      return {
+        cdnUrl: this.cdnUrl,
+        archives: tryExactArchives,
+      };
+    }
+    const allArchives = await this.getArchives(id, depotDto, version, (qb) =>
+      qb.andWhere(':requestedFiles && archive.files', { requestedFiles: requestedFiles }).orderBy('archive.size', 'ASC')
+    );
+    /*for (const archive of allArchives) {
+      archive.files = _.intersection(archive.files, requestedFiles);
+    }*/
+    const [archives] = this.getPartArchiveSubset(_.uniq(requestedFiles), allArchives);
+    if (!archives) {
+      throw new BlankReturnMessageDto(404, 'Some files of this build not found').toException();
+    }
+    return {
+      cdnUrl: this.cdnUrl,
+      archives,
     };
   }
 }