Angular发布报错：tipoInstrumento不存在于Instrumento类型 问题排查

问题背景 #

之前instrumentoPipe管道的返回值为Instrumento类型，使用ngFor实现表格列表渲染时，调试阶段运行完全正常，但执行项目发布操作时抛出如下错误：

Property 'tipoInstrumento' does not exist on type 'Instrumento'. Did you mean 'idInstrumento'?

已经在组件中定义了InstrumentoTipoInstrumento接口，且对instrumentos数组做了映射处理，明确包含tipoInstrumento字段，但模板中遍历得到的instrumento条目被识别为项目中另一个Instrumento模型类型，而非预期的InstrumentoTipoInstrumento类型。

相关代码 #

Instrumento.component.html #

</div><div class="main-content">
  <div class="row">
    <div class="col-md-12">
      <div class="card">
        <div class="card-title">
        </div>
        <div class="card-body">
          <h2>Instrumentos</h2>
          <p *ngIf="!instrumentos"><mat-spinner></mat-spinner></p>
          <div class="row align-items-center">
            <div class="col-md-1 text-center">
          <a *ngIf="instrumentos" routerLink="create/0" class="btn bs-tooltip-right"><i class="fas fa-address-card"></i> Crear</a>
            </div>
          <div class="col-md-6">
            <input class="form-control buscador" placeholder="Buscar instrumento" id="buscador" name="buscador" [(ngModel)]="value" >
          </div>
          </div>
          <table class='table table-hover' aria-labelledby="tableLabel" *ngIf="instrumentos">
            <thead>
              <tr>
                <th>Nombre instrumento</th>
                <th>Tipo instrumento</th>
              </tr>
            </thead>
            <tbody>
              <tr *ngFor="let instrumento of instrumentos|instrumentoPipe:value; let i = index">
                <td>{{ instrumento.nombreInstrumento }}</td>
                <td>{{ instrumento.tipoInstrumento }}</td>
                <td><a [routerLink]="['edit', instrumento.idInstrumento]" class="btn btn-info"><i class="fas fa-edit"></i> Editar</a></td>
                <td><a (click)="deleteInstrumento(instrumento.idInstrumento)" class="btn btn-danger"><i class="fas fa-trash"></i> Eliminar</a></td>
              </tr>
            </tbody>
          </table>
        </div>
      </div>
    </div>
  </div>
</div>

instrumento.component.ts #

import { Component, OnInit } from '@angular/core';
import { ThemePalette } from '@angular/material/core';
import { ProgressSpinnerMode } from '@angular/material/progress-spinner';
import { ActivatedRoute } from '@angular/router';
import { ToastrService } from 'ngx-toastr';
import { TipoInstrumento } from '../models/tipo-instrumento';
import { InstrumentoService } from '../services/instrumento.service';
import { TipoInstrumentoService } from '../services/tipo-instrumento.service';

@Component({
  selector: 'instrumento',
  templateUrl: './instrumento.component.html',
  styleUrls: ['./instrumento.component.css']
})
export class InstrumentoComponent implements OnInit {
  instrumentosSC: any[];
  instrumentos: InstrumentoTipoInstrumento[];
  tipoInstrumento: TipoInstrumento[];
  color: ThemePalette = 'primary';
  mode: ProgressSpinnerMode = 'indeterminate';
  value: string = '';

  constructor(private toastr: ToastrService, private instrumentoService: InstrumentoService, route: ActivatedRoute, private tipoInstrumentoService: TipoInstrumentoService) {
  }

  getInstrumento() {
    this.instrumentoService.GetInstrumento().subscribe(result => this.getTipoInstrumentos(result), error => this.toastr.error("Hubo un error al cargar los instrumentos" + error, "Error"));
  }

  deleteInstrumento(id: number) {
    this.instrumentoService.DeleteInstrumento(id).subscribe(result => this.toastr.success("Instrumento eliminado exitosamente", "Éxito"), error => this.toastr.error("Hubo un error al eliminar el instrumento " + error, "Error"));
  }

  getTipoInstrumentos(result) {
    this.instrumentosSC = result;
    this.tipoInstrumentoService.GetTipoInstrumento().subscribe(result => this.mapInstrumentos(result), error => this.toastr.error("Hubo un error al cargar Tipo Instrumento" + error, "Error"));
  }

  mapInstrumentos(result) {
    this.tipoInstrumento = result;
    this.instrumentos = this.instrumentosSC.map(instrumento => {
      return {
        idInstrumento: instrumento.idInstrumento,
        nombreInstrumento: instrumento.nombreInstrumento,
        tipoInstrumentoIdTipoInstrumento: instrumento.tipoInstrumentoIdTipoInstrumento,
        tipoInstrumento: this.getTipoInstrumentoById(instrumento.tipoInstrumentoIdTipoInstrumento).nombreTipoInstrumento
      }
    })
  }

  ngOnInit() {
    this.getInstrumento();
  }

  getTipoInstrumentoById(id: number) {
    console.log(id);
    return this.tipoInstrumento.find(tipoInstrumentos => {
      return tipoInstrumentos.idTipoInstrumento === id;
    })
  }
}

interface InstrumentoTipoInstrumento {
  idInstrumento?: number;
  nombreInstrumento: string;
  tipoInstrumentoIdTipoInstrumento: number;
  tipoInstrumento: string;
}

问题根源 #

Angular调试阶段默认使用JIT编译，类型检查较为宽松，而发布时会启用AOT编译，会对模板做严格的类型校验。你的instrumentoPipe管道返回值类型仍然声明为旧的Instrumento[]，导致经过管道处理后的数组类型被推断为Instrumento[]，和你组件中定义的InstrumentoTipoInstrumento[]不匹配，因此抛出属性不存在的错误。

解决方案 #

• 首选方案：修改instrumentoPipe管道的返回类型声明，将返回值从Instrumento[]调整为InstrumentoTipoInstrumento[]，同步修改管道内部逻辑的类型注解，保证管道输出类型和组件定义的数组类型完全一致，从根源解决类型不匹配问题。
• 临时规避方案：如果暂时不方便修改管道定义，可以在模板中使用$any方法做类型断言，修改ngFor写法即可：

  <tr *ngFor="let instrumento of $any(instrumentos|instrumentoPipe:value); let i = index">
  

• 优化建议：在tsconfig.json中开启严格模板类型检查配置，开发阶段就能提前发现这类类型问题，无需等到发布阶段才暴露。

内容的提问来源于stack exchange，提问作者SANTIAGO SANCHEZ BERRIO