Method loadModelJSON

tfjs-core/src/io/http.ts:138–178

()

  }

  private async loadModelJSON(): Promise<ModelJSON> {
    const modelConfigRequest = await this.fetch(this.path, this.requestInit);

    if (!modelConfigRequest.ok) {
      throw new Error(
          `Request to ${this.path} failed with status code ` +
          `${modelConfigRequest.status}. Please verify this URL points to ` +
          `the model JSON of the model to load.`);
    }
    let modelJSON: ModelJSON;
    try {
      modelJSON = await modelConfigRequest.json();
    } catch (e) {
      let message = `Failed to parse model JSON of response from ${this.path}.`;
      // TODO(nsthorat): Remove this after some time when we're comfortable that
      // .pb files are mostly gone.
      if (this.path.endsWith('.pb')) {
        message += ' Your path contains a .pb file extension. ' +
            'Support for .pb models have been removed in TensorFlow.js 1.0 ' +
            'in favor of .json models. You can re-convert your Python ' +
            'TensorFlow model using the TensorFlow.js 1.0 conversion scripts ' +
            'or you can convert your.pb models with the \'pb2json\'' +
            'NPM script in the tensorflow/tfjs-converter repository.';
      } else {
        message += ' Please make sure the server is serving valid ' +
            'JSON for this request.';
      }
      throw new Error(message);
    }

    // We do not allow both modelTopology and weightsManifest to be missing.
    const modelTopology = modelJSON.modelTopology;
    const weightsManifest = modelJSON.weightsManifest;
    if (modelTopology == null && weightsManifest == null) {
      throw new Error(
          `The JSON from HTTP path ${this.path} contains neither model ` +
          `topology or manifest for weights.`);
    }

    return modelJSON;
  }

  /**
   * Load model artifacts via HTTP request(s).