Javascript client produces a wrong object for a string enum type that is used with $ref

[knzm]

Description

I got something like { '0': 'f', '1': 'i', '2': 's', '3': 'h' } for an enum type. It should be "fish".

Swagger-codegen version

2.2.2-SNAPSHOT (revision: bb81fc1)

Swagger declaration file content or url

swagger: "2.0"
info:
  version: 1.0.0
schemes:
  - http
paths:
  /pet:
    post:
      parameters:
      responses:
        '405':
          description: Invalid input

definitions:
  EnumArrays:
    type: object
    properties:
      array_enum:
        type: array
        items:
          type: string
          enum:
            - fish
            - crab
      array_enum_ref:
        type: array
        items:
          $ref: '#/definitions/StringEnumObject'
  StringEnumObject:
    type: string
    enum:
      - fish
      - crab

Command line used for generation

$ java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate -i test.yaml -l javascript -o output

Steps to reproduce

1. Run codegen by the above command
2. Cd into output directory, then run npm install
3. Start a node interactive shell and type them:

$ node
> var SwaggerClient = require('./src')
> SwaggerClient.EnumArrays.constructFromObject({"array_enum": ["fish", "crab"]})
exports { array_enum: [ 'fish', 'crab' ] }
> SwaggerClient.EnumArrays.constructFromObject({"array_enum_ref": ["fish", "crab"]})
exports {
  array_enum_ref: 
   [ { '0': 'f', '1': 'i', '2': 's', '3': 'h' },
     { '0': 'c', '1': 'r', '2': 'a', '3': 'b' } ] }

Related issues

I did not find any known issues about it. However, there were a number of bugs related to enum types with Javascript client in the past.

#3639 [javascript client] constructFromObject calls undefined function constructFromObject on enums
#3416 [JavaScript] String Enum types produce invalid code
#2102 [JavaScript] Enums are not exported correctly

Suggest a Fix

I can fix the issue by modifying convertToType method defined in ApiClient.mustache like this:

--- a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
@@ -470,7 +470,7 @@
         if (type === Object) {
           // generic object, return directly
           return data;
-        } else if (typeof type === 'function') {
+        } else if (typeof type.constructFromObject === 'function') {
           // for model type like: User
           return type.constructFromObject(data);
         } else if (Array.isArray(type)) {

I think ApiClient.convertToType() can always call type.constructFromObject() for types that have constructFromObject method. But I'm not sure about its side effects.

[advance512]

I can confirm this. It is a major bug that basically prevents using arrays of enums.

  Language:
    type: string
    enum:
      - LANGUAGE_ar
      - LANGUAGE_bg
      - LANGUAGE_ca
      - LANGUAGE_zh_CN
      - LANGUAGE_zh_TW
      - LANGUAGE_hr
      - LANGUAGE_cs
      - LANGUAGE_da
      - LANGUAGE_nl
      - LANGUAGE_en
      - LANGUAGE_et
      - LANGUAGE_tl
      - LANGUAGE_fi
      - LANGUAGE_fr
      - LANGUAGE_de
      - LANGUAGE_el
      - LANGUAGE_iw
      - LANGUAGE_hi
      - LANGUAGE_hu
      - LANGUAGE_is
      - LANGUAGE_id
      - LANGUAGE_it
      - LANGUAGE_ja
      - LANGUAGE_ko
      - LANGUAGE_lv
      - LANGUAGE_lt
      - LANGUAGE_ms
      - LANGUAGE_no
      - LANGUAGE_fa
      - LANGUAGE_pl
      - LANGUAGE_pt
      - LANGUAGE_ro
      - LANGUAGE_ru
      - LANGUAGE_sr
      - LANGUAGE_sk
      - LANGUAGE_sl
      - LANGUAGE_es
      - LANGUAGE_sv
      - LANGUAGE_th
      - LANGUAGE_tr
      - LANGUAGE_uk
      - LANGUAGE_ur
      - LANGUAGE_vi


  SomeDefinition:
    type: object
    properties:
      languages:
        type: array
        minItems: 0
        maxItems: 3
        uniqueItems: true
        items:
          $ref: '#/definitions/Language'

Instead of returning an array of strings, I return an array of characters - e.g.
['L', 'A', 'N', 'G', 'U', 'A', 'G', 'E', '_', 'a', 'r']

This is because in the generated ApiClient.js, in convertToType() you see:

        } else if (typeof type === 'object') {
          // for plain object type like: {'String': 'Integer'}
          var keyType, valueType;
          for (var k in type) {
            if (type.hasOwnProperty(k)) {
              keyType = k;
              valueType = type[k];
              break;
            }
          }
          var result = {};
          for (var k in data) {
            if (data.hasOwnProperty(k)) {
              var key = exports.convertToType(k, keyType);
              var value = exports.convertToType(data[k], valueType);
              result[key] = value;
            }
          }
          return result;

Now, the $ref should return a type of string, but instead it returns an object.. and then in for (var k in data) it just iterates over the characters of the string.

This looks similar to another bug I found that was with refs to primitive types:
#4973

[advance512]

I managed to go around this issue by explicitly including the type:

  SomeDefinition:
    type: object
    properties:
      languages:
        type: array
        minItems: 0
        maxItems: 3
        uniqueItems: true
        items:
          type: string
          enum:
                  - LANGUAGE_ar
                  - LANGUAGE_bg
                  - LANGUAGE_ca
                  - LANGUAGE_zh_CN
                  - LANGUAGE_zh_TW
                  - LANGUAGE_hr
                  - LANGUAGE_cs
                  - LANGUAGE_da
                  - LANGUAGE_nl
                  - LANGUAGE_en
                  - LANGUAGE_et
                  - LANGUAGE_tl
                  - LANGUAGE_fi
                  - LANGUAGE_fr
                  - LANGUAGE_de
                  - LANGUAGE_el
                  - LANGUAGE_iw
                  - LANGUAGE_hi
                  - LANGUAGE_hu
                  - LANGUAGE_is
                  - LANGUAGE_id
                  - LANGUAGE_it
                  - LANGUAGE_ja
                  - LANGUAGE_ko
                  - LANGUAGE_lv
                  - LANGUAGE_lt
                  - LANGUAGE_ms
                  - LANGUAGE_no
                  - LANGUAGE_fa
                  - LANGUAGE_pl
                  - LANGUAGE_pt
                  - LANGUAGE_ro
                  - LANGUAGE_ru
                  - LANGUAGE_sr
                  - LANGUAGE_sk
                  - LANGUAGE_sl
                  - LANGUAGE_es
                  - LANGUAGE_sv
                  - LANGUAGE_th
                  - LANGUAGE_tr
                  - LANGUAGE_uk
                  - LANGUAGE_ur
                  - LANGUAGE_vi

Very sub-optimal, but it works for now.

[wing328]

@knzm can you please submit a PR so that we can review the fix?

[wing328]

@advance512 can you try the fix suggested by @knzm to see if that works for you?

[advance512]

Unfortunately, his fix doesn't help me since I am dependent on auto-generated code and don't want to add any manual steps in. I can try his fix one time, just to see if it helps. Will try to do it this week and update

[wing328]

Please try to test it locally. If it works, we'll incorpoate the fix into the mustache template.

…

On Thu, Mar 30, 2017 at 12:11 PM, Alon Diamant ***@***.***> wrote: Unfortunately, his fix doesn't help me since I am dependent on auto-generated code and don't want to add any manual steps in. I can try his fix one time, just to see if it helps. Will try to do it this week and update — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#4819 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA5BdBpaAjc-Ez2DAbEoB25J_fkZjXdFks5rqyuBgaJpZM4MElIA> .

[kirpit]

I have tried to reproduce this bug with the exact given specs (current latest master) but looks like problem is already gone, despite to the suggested change (for } else if (typeof type === 'function') {) is not there.

Here are the pieces of correctly generated model definitions:

EnumArrays:

  /**
   * Allowed values for the <code>arrayEnum</code> property.
   * @enum {String}
   * @readonly
   */
  exports.ArrayEnumEnum = {
    /**
     * value: "fish"
     * @const
     */
    "fish": "fish",
    /**
     * value: "crab"
     * @const
     */
    "crab": "crab"  };

StringEnumObject:

  /**
   * Enum class StringEnumObject.
   * @enum {}
   * @readonly
   */
  var exports = {
    /**
     * value: "fish"
     * @const
     */
    "fish": "fish",
    /**
     * value: "crab"
     * @const
     */
    "crab": "crab"  };

@knzm, any chance to confirm and close the issue?

[wing328]

@kirpit thanks for performing more tests to confirm the issue no longer exists.

@knzm please try the latest master and let us know if you still encounter the issue.

[advance512]

I still see this issue.

Using swagger-codegen-cli-3.0.0-20170727.135949-1.jar with the command line:

java -jar ~/Downloads/swagger-codegen-cli-3.0.0-20170727.135949-1.jar generate -i ../fizzle.yaml -l javascript --additional-properties usePromises=true --additional-properties useES6=false -o ./javascript/

I see that arrays of strings get converted into arrays of objects with indexes as keys and each char as the value. e.g.

[
  {
    "0": "I",
    "1": "N",
    "2": "C",
    "3": "R",
    "4": "E",
    "5": "A",
    "6": "S",
    "7": "E",
    "8": "_",
    "9": "S",
    "10": "E",
    "11": "A",
    "12": "R",
    "13": "C",
    "14": "H",
    "15": "_",
    "16": "E",
    "17": "N",
    "18": "G",
    "19": "I",
    "20": "N",
    "21": "E",
    "22": "_",
    "23": "R",
    "24": "A",
    "25": "N",
    "26": "K",
    "27": "I",
    "28": "N",
    "29": "G",
    "30": "S"
  },
  {
    "0": "G",
    "1": "E",
    "2": "T",
    "3": "_",
    "4": "B",
    "5": "L",
    "6": "O",
    "7": "G",
    "8": "S",
    "9": "_",
    "10": "E",
    "11": "N",
    "12": "D",
    "13": "O",
    "14": "R",
    "15": "S",
    "16": "E",
    "17": "M",
    "18": "E",
    "19": "N",
    "20": "T"
  },
  {
    "0": "I",
    "1": "N",
    "2": "C",
    "3": "R",
    "4": "E",
    "5": "A",
    "6": "S",
    "7": "E",
    "8": "_",
    "9": "B",
    "10": "R",
    "11": "A",
    "12": "N",
    "13": "D",
    "14": "_",
    "15": "A",
    "16": "W",
    "17": "A",
    "18": "R",
    "19": "E",
    "20": "N",
    "21": "E",
    "22": "S",
    "23": "S"
  },
  {
    "0": "G",
    "1": "E",
    "2": "N",
    "3": "E",
    "4": "R",
    "5": "A",
    "6": "T",
    "7": "E",
    "8": "_",
    "9": "M",
    "10": "O",
    "11": "R",
    "12": "E",
    "13": "_",
    "14": "T",
    "15": "R",
    "16": "A",
    "17": "F",
    "18": "F",
    "19": "I",
    "20": "C"
  }
]

This should be, of course, an simple array of 4 strings.

[
  "INCREASE_SEARCH_ENGINE_RANKINGS",
  "GET_BLOGS_ENDORSEMENT",
  "INCREASE_BRAND_AWARENESS",
  "GENERATE_MORE_TRAFFIC"
]

Once again, looking at the generated ApiClient.js:518, you see that:

        } else if (Array.isArray(type)) {
          // for array type like: ['String']
          var itemType = type[0];
          return data.map(function(item) {
            return exports.convertToType(item, itemType);
          });

Now, wth the context being:

data = [
  "INCREASE_SEARCH_ENGINE_RANKINGS",
  "GET_BLOGS_ENDORSEMENT",
  "INCREASE_BRAND_AWARENESS",
  "GENERATE_MORE_TRAFFIC"
]; 
type = [
  {
    "GENERATE_MORE_TRAFFIC": "GENERATE_MORE_TRAFFIC",
    "GENERATE_MORE_CONVERSIONS": "GENERATE_MORE_CONVERSIONS",
    "INCREASE_SEARCH_ENGINE_RANKINGS": "INCREASE_SEARCH_ENGINE_RANKINGS",
    "SOCIAL_MEDIA_PRESENCE": "SOCIAL_MEDIA_PRESENCE",
    "GET_BLOGS_ENDORSEMENT": "GET_BLOGS_ENDORSEMENT",
    "ENTER_A_NEW_MARKET": "ENTER_A_NEW_MARKET",
    "IMPROVE_BRAND_IMAGE": "IMPROVE_BRAND_IMAGE",
    "INCREASE_BRAND_AWARENESS": "INCREASE_BRAND_AWARENESS",
    "APP_INSTALLS": "APP_INSTALLS",
    "LEADS_OR_SIGN_UP": "LEADS_OR_SIGN_UP",
    constructFromObject(obj): function(object) {
        return object;
     },
  }
];

the type is an Array of enum strings, so itemType becomes the Object shown above, and then you recursively enter exports.convertToType(data, type) which is then with data being a string with an enum val (e.g. "INCREASE_SEARCH_ENGINE_RANKINGS") and type being the Object, so you get to this part:

        } else if (typeof type === 'object') {
            if (type.hasOwnProperty(k)) {
              keyType = k;
              valueType = type[k];
              break;
            }
          }
          var result = {};
          for (var k in data) {
            if (data.hasOwnProperty(k)) {
              var key = exports.convertToType(k, keyType);
              var value = exports.convertToType(data[k], valueType);
              result[key] = value;
            }
          }
          return result;
        } else {

Now, when you get to the line: for (var k in data) { everything gets jumbled.

for..in used on a string has the following behavior:

> for (var k in "abcdef") { console.log(k); }
0
1
2
3
4
5

These are actually "0", "1", "2". Not even numeric values.

Now, remember, data is a string. So k becomes the index of the first character in string form, e.g. "0", and key gets the value of k, while value get the char itself. This is written into the result as seen above.

{
    "0": "I",
    "1": "N",
    "2": "C",
    "3": "R",
    "4": "E",
    "5": "A",
    ...

The issue here is that we get to a point where the type is an object with possible string Enum values, the data is a string, but instead of looking at the entire string as the string value to check against the Enum we get a index -> character Object.