[TS][Fetch] Add support for openapi maps/dictionaries to be generated as typescript map

[ehvattum]

PR checklist

• Read the contribution guidelines.
• Ran the shell script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh, ./bin/openapi3/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates). Windows batch files can be found in .\bin\windows\. If contributing template-only or documentation-only changes which will change sample output, be sure to build the project first.
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cc. @TiFu @taxpon @sebastianhaas @kenisteward @Vrolijkx @macjohnny @nicokoenig @topce

Description of the PR

• Add support for openapi maps/dictionaries to be generated as typescript map.
• Fix is .mustache files only.
• Reason for PR: consumption of openapi api with map collections. The typescript-fetch generator failed to create working code by mapping it as an array.
• related previous issue: [BUG][typescript-fetch] Additional properties are treated as array #1878

[macjohnny]

can you provide an minimal example .yml file and the corresponding output?

[macjohnny]

LGTM

[ehvattum]

@macjohnny Given an example 2.0 spec in json as the first code block here, this PR allows generation of code files like the bottom block.

{
    "swagger": "2.0",
    "info": { "version": "1.0", "title": "map-spec 1.0" },
    "paths":{},
    "definitions": {
        "Measurements": {
            "type": "object",
            "properties": {
                "meteringPointId": { "type": "string" },
                "year": { "$ref": "#/definitions/AggregatedMeasurements" },
                "month": { "type": "object", "additionalProperties": { "$ref": "#/definitions/AggregatedMeasurements" } },
                "day": { "type": "object", "additionalProperties": { "$ref": "#/definitions/AggregatedMeasurements" } },
                "hour": { "type": "object", "additionalProperties": { "$ref": "#/definitions/AggregatedMeasurements" } }
            }
        },
        "AggregatedMeasurements": {
            "type": "object",
            "properties": {
                "min": { "format": "double", "type": "number" },
                "max": { "format": "double", "type": "number" },
                "avg": { "format": "double", "type": "number" },
                "values": { "type": "object", "additionalProperties": { "$ref": "#/definitions/Volume" } }
            }
        },
        "Volume": {
            "type": "object",
            "properties": {
                "value": { "format": "double", "type": "number" },
                "status": { "enum": ["OK", "Est"], "type": "string" },
                "resolution": { "enum": ["Quarter", "Hour", "Month"], "type": "string" }
            }
        }
    }
}

AggregatedMeasurements.ts

// tslint:disable
/**
 * map-spec 1.0
 * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
 *
 * The version of the OpenAPI document: 1.0
 * 
 *
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
 * https://openapi-generator.tech
 * Do not edit the class manually.
 */

import { exists, mapValues } from '../runtime';
import {
    AggregatedMeasurements,
    AggregatedMeasurementsFromJSON,
    AggregatedMeasurementsToJSON,
} from './';

/**
 * 
 * @export
 * @interface Measurements
 */
export interface Measurements {
    /**
     * 
     * @type {string}
     * @memberof Measurements
     */
    meteringPointId?: string;
    /**
     * 
     * @type {AggregatedMeasurements}
     * @memberof Measurements
     */
    year?: AggregatedMeasurements;
    /**
     * 
     * @type {{ [key: string]: AggregatedMeasurements; }}
     * @memberof Measurements
     */
    month?: { [key: string]: AggregatedMeasurements; };
    /**
     * 
     * @type {{ [key: string]: AggregatedMeasurements; }}
     * @memberof Measurements
     */
    day?: { [key: string]: AggregatedMeasurements; };
    /**
     * 
     * @type {{ [key: string]: AggregatedMeasurements; }}
     * @memberof Measurements
     */
    hour?: { [key: string]: AggregatedMeasurements; };
}

export function MeasurementsFromJSON(json: any): Measurements {
    return {
        'meteringPointId': !exists(json, 'meteringPointId') ? undefined : json['meteringPointId'],
        'year': !exists(json, 'year') ? undefined : AggregatedMeasurementsFromJSON(json['year']),
        'month': !exists(json, 'month') ? undefined : mapValues(json['month'], AggregatedMeasurementsFromJSON),
        'day': !exists(json, 'day') ? undefined : mapValues(json['day'], AggregatedMeasurementsFromJSON),
        'hour': !exists(json, 'hour') ? undefined : mapValues(json['hour'], AggregatedMeasurementsFromJSON),
    };
}

export function MeasurementsToJSON(value?: Measurements): any {
    if (value === undefined) {
        return undefined;
    }
    return {
        'meteringPointId': value.meteringPointId,
        'year': AggregatedMeasurementsToJSON(value.year),
        'month': value.month === undefined ? undefined : mapValues(value.month, AggregatedMeasurementsToJSON),
        'day': value.day === undefined ? undefined : mapValues(value.day, AggregatedMeasurementsToJSON),
        'hour': value.hour === undefined ? undefined : mapValues(value.hour, AggregatedMeasurementsToJSON),
    };
}

[TiFu]

Thanks for the PR! Looks good to me.

[wing328]

@ehvattum thanks again for your contribution, which has been included in the v4.0.1 release (https://twitter.com/oas_generator/status/1135534738658062336)