Feature: Add support to recognise custom json media-types

[alefranz]

Hi,

This is a feature request to add support to recognise as json custom media types: e.g. application/vnd.*+json.

I think it could be either match on this pattern (or just +json) or open the BodyParser so it can be customized or media-types can be registered.

Specifically I'm after the ability to correctly save the payload as json when saving the auto generated mappings (when capturing as proxy).

If you are open to the idea I can contribute a PR for this.

[StefH]

Or define at the mapping that the request body should be parsed as String, Json or Bytes by using a new property at the body mapping named ParseBodyAs.

Using this new setting overrides the default Content-Type logic.

Example

{
    "Guid": "debaf408-3b23-4c04-9d18-ef1c020e79f3",
    "Request": {
        "Path": {
            "Matchers": [
                {
                    "Name": "WildcardMatcher",
                    "Pattern": "/jsonbodytest2",
                    "IgnoreCase": true
                }
            ]
        },
        "Methods": [
            "post"
        ],
        "Body": {
            "ParseBodyAs": "Json",
            "Matcher": {
                "Name": "JsonMatcher",
                "Pattern": {
                  "x": 42,
                  "s": "s"
                }
            }
        }
    },
    "Response": {
        "StatusCode": 200,
        "Body": "{ \"result\": \"jsonbodytest2\" }"
    }
}

[lesnes]

i am very interested in this new feature (ParseBodyAs). currently, BodyParser only supports parsing as string for certain content types. this means that one cannot use IStringMatcher implementations for matching request Body when content type is something like multipart/form-data.

when do you expect to release a new version to nuget that includes this functionality ? is it on a branch that i could take a look at?

[StefH]

I'll take a look and start building this new functionality.

[lesnes]

that would be great, thanks!

[alefranz]

@StefH is there a way to specify ParseBodyAs with the fluent syntax? and what about in the ProxyAndRecordSettings?

[StefH]

Hello @lesnes and @alefranz, I'm currently working on a PR https://github.com/WireMock-Net/WireMock.Net/pull/212 which updates the logic for the body parser.

In short:

• Using a IStringMatcher will always work because the BodyAsString is always filled.
• Using a IObjectMatcher like JsonMatcher, JsonPathMatcher and LinqMatcher will work in case it's a Json object

Please have a look to see if this will solve your questions.

[alefranz]

In the current version I believe sometimes you only have the body as bytes. Also matching a json with a string is often a pain as the sample response data for the mock are usually not minified, so in my scenario I still need the ability to change something in DetectBodyTypeFromContentType to be able to set custom media type as json. Ideally would be nice for that class to not be static and the library support to extend it but that seems quite a lot of work. What about using a regex and testing against application/vnd\..*+json?

[StefH]

1. The property DetectBodyTypeFromContentType is not really used in the logic, it's just for information.

The Content-Type is not used anymore in the logic now.

The real logic is done with the DetectedBodyType.

2. I can implement application/vnd\..*+json as a RegEx if you like, but the logic is not really used.

[alefranz]

Ok, I guess I didn't really get the gist of the PR. I'll have a better look. Do you publish the PR builds as prerelease on myget by any chance?

[StefH]

Added a preview version to MyGet https://www.myget.org/F/wiremock-net/api/v3/index.json

[lesnes]

wow, that was quick. great job! looks like it would suit my purposes

[StefH]

@alefranz PR build is published at https://www.myget.org/feed/wiremock-net/package/nuget/WireMock.Net / https://www.myget.org/F/wiremock-net/api/v3/index.json

Can you please test this one ?

[lesnes]

i've tested my usage requirement for multipart/form-data against 1.0.4.18-ci-1343 and it is working now 👍

[StefH]

Good news.

@alefranz : If you can confirm this issue and also the other issue; I can create a new official build.

[alefranz]

Apologies, I will be able to test only on Monday.

[alefranz]

Nice, now the mapping has the body as json, however when I save the mappings with SaveStaticMappings I end up with all 3 versions of it (text, json and binary) in the json. It would be nice to define which format to save in SaveStaticMappings

[StefH]

Ah, I did not think of that. By default, the mapping should only be saved for the DetectedBodyType, just as it is now. I'll fix this and a new version should be automatically added to MyGet once it's ready.

Saving all 3 would be an additional option, which will be available in the next version.

[alefranz]

but in my scenario with application/vnd.*+json what would be the DetectedBodyType?

[StefH]

@alefranz When I think about it again...

1] The DetectBodyType will be be based on the body, not on content-type.

2] The DetectBodyTypeFromContentType will be be based on the content-type, but it's not used in the logic.

3] I think you mean /__admin/requests or RequestsGet() ? That code does indeed save all 3 versions:

"Body": "{ \"things\": [ { \"name\": \"RequiredThing\" }, { \"name\": \"Wiremock\" } ] }",
"BodyAsJson": {
    "things": [
        {
            "name": "RequiredThing"
        },
        {
            "name": "Wiremock"
        }
    ]
},
"BodyAsBytes": "eyAidGhpbmdzIjogWyB7ICJuYW1lIjogIlJlcXVpcmVkVGhpbmciIH0sIHsgIm5hbWUiOiAiV2lyZW1vY2siIH0gXSB9",

This I can update.

[alefranz]

This is my workflow:

• I start the mock as proxy

  ProxyAndRecordSettings = new ProxyAndRecordSettings
              {
                  Url = originaUrl,
                  SaveMapping = true,
                  SaveMappingToFile = false
              };

• I execute my end to end flow
• on shutdown I use SaveStaticMappings to save the generated mapping (which contains the proxied response) to a specific folder (as with SaveMappingToFile I can't specify a folder, but I have multiple mocks running so I need to separate those)

All this responses are json but I have custom media types application/vnd.*+json.

The purpose of this is to automatically generate the mappings to load in my tests.

My goal is to have only BodyAsJson in the saved mapping as it is the readable one.

[StefH]

I see your point. Can you try latest from the MyGet feed: 1.0.4.18-ci-1349 ?

See https://github.com/WireMock-Net/WireMock.Net/wiki/MyGet-preview-versions for details on MyGet

[StefH]

@alefranz : did you have time to test the latest version on MyGet?

[alefranz]

Apologies for the delay.

It works like a charm!

Thanks!

[StefH]

@alefranz Are you sure you tested the 1.0.4.18-ci-1349 (or later) MyGet version ?

[alefranz]

Yes, I've tested 1.0.4.18-ci-1349 and the saved mapping contains only the BodyAsJson as desired

[alefranz]

Thank you!