Reporter flush failed when using with Jaeger backend

[longit644]

When I use Kong Zipkin plugin with Jaeger backend, I got an error with the response body:

Unable to process request body: json: cannot unmarshal number into Go struct field Span.tags of type string

Kong version: 0.14.0rc1 on docker.

Request body of Reporter:

[
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "d4097ab8438f67b0",
        "name": "kong.rewrite",
        "parentId": "ec270a5446cd8a68",
        "remoteEndpoint": null,
        "duration": 0,
        "timestamp": 1.530259357671e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "8a63117b77519823",
        "name": "kong.header_filter",
        "parentId": "842b5d62df16ba9d",
        "remoteEndpoint": null,
        "duration": 0,
        "timestamp": 1.530259357673e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "6188f6111cb62a67",
        "name": "kong.access",
        "parentId": "842b5d62df16ba9d",
        "remoteEndpoint": null,
        "duration": 999,
        "timestamp": 1.530259357671e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "16517979531c5062",
        "tags": {
            "kong.balancer.try": 1,
            "peer.port": 9500,
            "peer.ipv4": "10.148.7.194"
        },
        "name": "kong.balancer",
        "parentId": "842b5d62df16ba9d",
        "remoteEndpoint": {
            "ipv4": "10.148.7.194",
            "port": 9500
        },
        "duration": 0,
        "timestamp": 1.530259357672e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "cc23407a6eb33e4f",
        "name": "kong.body_filter",
        "parentId": "842b5d62df16ba9d",
        "remoteEndpoint": null,
        "duration": 0,
        "timestamp": 1.530259357673e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "842b5d62df16ba9d",
        "tags": {
            "peer.service": "test",
            "peer.port": 9500,
            "peer.ipv4": "10.148.7.194",
            "kong.service": "b1a71321-3b6d-46ef-b376-11e7275c3f36",
            "kong.route": "107bb250-a65f-4915-8731-1d7b860bdba7",
            "peer.hostname": "10.148.7.194",
            "span.kind": "client"
        },
        "name": "kong.proxy",
        "parentId": "ec270a5446cd8a68",
        "kind": "CLIENT",
        "remoteEndpoint": {
            "ipv4": "10.148.7.194",
            "port": 9500
        },
        "duration": 2000,
        "timestamp": 1.530259357671e+15
    },
    {
        "traceId": "9aa46f78b4afbd37e6845ba62313d51d",
        "localEndpoint": null,
        "id": "ec270a5446cd8a68",
        "tags": {
            "http.status_code": 400,
            "span.kind": "server",
            "peer.ipv4": "172.17.0.1",
            "http.method": "GET",
            "peer.port": 47580,
            "http.url": "http:\/\/localhost:8000\/test",
            "component": "kong"
        },
        "name": "kong.request",
        "kind": "SERVER",
        "remoteEndpoint": {
            "ipv4": "172.17.0.1",
            "port": 47580
        },
        "duration": 2000,
        "timestamp": 1.530259357671e+15
    }
]