# All files / core/router router-explorer.ts

98.15% Statements 53/54
71.43% Branches 10/14
100% Functions 12/12
98.11% Lines 52/53

    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    1891x

    1x
    1x

    1x
    1x
    1x
    1x
    1x

    1x
    1x

    1x
    1x

    1x
    1x

    1x

    21x
    21x

    21x

    21x
    21x
    21x

    21x

    1x
    1x

    2x
    2x
    2x

    13x
    1x

    12x

    4x

    4x

    8x

    9x
    9x
    9x

    9x

    9x

    2x
    4x
    4x

    4x

    2x
    2x

    2x

    2x
    4x
    2x
    2x

    2x

    2x

    2x

     import { METHOD_METADATA, PATH_METADATA } from '@nestjs/common/constants';
    import { RequestMethod } from '@nestjs/common/enums/request-method.enum';
    import { Controller } from '@nestjs/common/interfaces/controllers/controller.interface';
    import { Type } from '@nestjs/common/interfaces/type.interface';
    import { Logger } from '@nestjs/common/services/logger.service';
    import { isUndefined, validatePath } from '@nestjs/common/utils/shared.utils';
    import { ApplicationConfig } from '../application-config';
    import { UnknownRequestMappingException } from '../errors/exceptions/unknown-request-mapping.exception';
    import { GuardsConsumer } from '../guards/guards-consumer';
    import { GuardsContextCreator } from '../guards/guards-context-creator';
    import { ROUTE_MAPPED_MESSAGE } from '../helpers/messages';
    import { RouterMethodFactory } from '../helpers/router-method-factory';
    import { NestContainer } from '../injector/container';
    import { InterceptorsConsumer } from '../interceptors/interceptors-consumer';
    import { InterceptorsContextCreator } from '../interceptors/interceptors-context-creator';
    import { MetadataScanner } from '../metadata-scanner';
    import { PipesConsumer } from '../pipes/pipes-consumer';
    import { PipesContextCreator } from '../pipes/pipes-context-creator';
    import { ExceptionsFilter } from './interfaces/exceptions-filter.interface';
    import { RouteParamsFactory } from './route-params-factory';
    import { RouterExecutionContext } from './router-execution-context';
    import { RouterProxy, RouterProxyCallback } from './router-proxy';

    export interface RoutePathProperties {
      path: string;
      requestMethod: RequestMethod;
      targetCallback: RouterProxyCallback;
      methodName: string;
    }

    export class RouterExplorer {
      private readonly executionContextCreator: RouterExecutionContext;
      private readonly routerMethodFactory = new RouterMethodFactory();
      private readonly logger = new Logger(RouterExplorer.name, true);

      constructor(
        private readonly metadataScanner: MetadataScanner,
        container: NestContainer,
        private readonly routerProxy?: RouterProxy,
        private readonly exceptionsFilter?: ExceptionsFilter,
        private readonly config?: ApplicationConfig,
      ) {
        this.executionContextCreator = new RouterExecutionContext(
          new RouteParamsFactory(),
          new PipesContextCreator(container, config),
          new PipesConsumer(),
          new GuardsContextCreator(container, config),
          new GuardsConsumer(),
          new InterceptorsContextCreator(container, config),
          new InterceptorsConsumer(),
          container.getApplicationRef(),
        );
      }

      public explore(
        instance: Controller,
        metatype: Type<Controller>,
        module: string,
        appInstance,
        basePath: string,
      ) {
        const routerPaths = this.scanForPaths(instance);
        this.applyPathsToRouterProxy(
          appInstance,
          routerPaths,
          instance,
          module,
          basePath,
        );
      }

      public extractRouterPath(
        metatype: Type<Controller>,
        prefix?: string,
      ): string {
        let path = Reflect.getMetadata(PATH_METADATA, metatype);
        if (prefix) path = prefix + this.validateRoutePath(path);
        return this.validateRoutePath(path);
      }

      public validateRoutePath(path: string): string {
        if (isUndefined(path)) {
          throw new UnknownRequestMappingException();
        }
        return validatePath(path);
      }

      public scanForPaths(instance: Controller, prototype?): RoutePathProperties[] {
        const instancePrototype = isUndefined(prototype)
          ? Object.getPrototypeOf(instance)
          : prototype;
        return this.metadataScanner.scanFromPrototype<
          Controller,
          RoutePathProperties
        >(instance, instancePrototype, method =>
          this.exploreMethodMetadata(instance, instancePrototype, method),
        );
      }

      public exploreMethodMetadata(
        instance: Controller,
        instancePrototype,
        methodName: string,
      ): RoutePathProperties {
        const targetCallback = instancePrototype[methodName];
        const routePath = Reflect.getMetadata(PATH_METADATA, targetCallback);
        Iif (isUndefined(routePath)) {
          return null;
        }
        const requestMethod: RequestMethod = Reflect.getMetadata(
          METHOD_METADATA,
          targetCallback,
        );
        return {
          path: this.validateRoutePath(routePath),
          requestMethod,
          targetCallback,
          methodName,
        };
      }

      public applyPathsToRouterProxy(
        router,
        routePaths: RoutePathProperties[],
        instance: Controller,
        module: string,
        basePath: string,
      ) {
        (routePaths || []).forEach(pathProperties => {
          const { path, requestMethod } = pathProperties;
          this.applyCallbackToRouter(
            router,
            pathProperties,
            instance,
            module,
            basePath,
          );
          this.logger.log(ROUTE_MAPPED_MESSAGE(path, requestMethod));
        });
      }

      private applyCallbackToRouter(
        router,
        pathProperties: RoutePathProperties,
        instance: Controller,
        module: string,
        basePath: string,
      ) {
        const { path, requestMethod, targetCallback, methodName } = pathProperties;
        const routerMethod = this.routerMethodFactory
          .get(router, requestMethod)
          .bind(router);

        const proxy = this.createCallbackProxy(
          instance,
          targetCallback,
          methodName,
          module,
          requestMethod,
        );
        const stripSlash = str =>
          str[str.length - 1] === '/' ? str.slice(0, str.length - 1) : str;
        const fullPath = stripSlash(basePath) + path;
        routerMethod(stripSlash(fullPath) || '/', proxy);
      }

      private createCallbackProxy(
        instance: Controller,
        callback: RouterProxyCallback,
        methodName: string,
        module: string,
        requestMethod,
      ) {
        const executionContext = this.executionContextCreator.create(
          instance,
          callback,
          methodName,
          module,
          requestMethod,
        );
        const exceptionFilter = this.exceptionsFilter.create(
          instance,
          callback,
          module,
        );
        return this.routerProxy.createProxy(executionContext, exceptionFilter);
      }
    }