http.go

package trigger

import (
	"bytes"
	"context"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"github.com/kubeshop/tracetest/server/expression"
	"github.com/kubeshop/tracetest/server/model"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/trace"
)

func HTTP() Triggerer {
	return &httpTriggerer{}
}

type httpTriggerer struct{}

func httpClient() http.Client {
	transport := &http.Transport{
		DialContext: (&net.Dialer{
			Timeout: time.Second,
		}).DialContext,
	}

	return http.Client{
		Transport: transport,
		Timeout:   30 * time.Second,
	}
}

func newSpanContext(ctx context.Context) trace.SpanContext {
	spanCtx := trace.SpanContextFromContext(ctx)
	var (
		tid trace.TraceID
		sid trace.SpanID
	)
	if spanCtx.IsValid() {
		tid = spanCtx.TraceID()
		sid = spanCtx.SpanID()
	}

	tracestate, _ := trace.ParseTraceState("tracetest=true")
	var tf trace.TraceFlags
	return trace.NewSpanContext(trace.SpanContextConfig{
		TraceID:    tid,
		SpanID:     sid,
		TraceFlags: tf.WithSampled(true),
		TraceState: tracestate,
		Remote:     true,
	})
}

func (te *httpTriggerer) Trigger(ctx context.Context, test model.Test, opts *TriggerOptions) (Response, error) {
	response := Response{
		Result: model.TriggerResult{
			Type: te.Type(),
		},
	}

	trigger := test.ServiceUnderTest
	if trigger.Type != model.TriggerTypeHTTP {
		return response, fmt.Errorf(`trigger type "%s" not supported by HTTP triggerer`, trigger.Type)
	}

	client := httpClient()

	ctx = trace.ContextWithSpanContext(ctx, newSpanContext(ctx))
	ctx, cncl := context.WithTimeout(ctx, 30*time.Second)
	defer cncl()

	tReq := trigger.HTTP
	var body io.Reader
	if tReq.Body != "" {
		body = bytes.NewBufferString(tReq.Body)
	}

	parsedUrl, err := url.Parse(tReq.URL)
	if err != nil {
		return response, err
	}

	if parsedUrl.Scheme == "" {
		parsedUrl.Scheme = "http"
	}

	req, err := http.NewRequestWithContext(ctx, strings.ToUpper(string(tReq.Method)), parsedUrl.String(), body)
	if err != nil {
		return response, err
	}
	for _, h := range tReq.Headers {
		req.Header.Add(h.Key, h.Value)
	}

	tReq.Authenticate(req)
	propagators().Inject(ctx, propagation.HeaderCarrier(req.Header))

	resp, err := client.Do(req.WithContext(ctx))
	if err != nil {
		return response, err
	}

	mapped := mapResp(resp)
	response.Result.HTTP = &mapped
	response.SpanAttributes = map[string]string{
		"tracetest.run.trigger.http.response_code": strconv.Itoa(resp.StatusCode),
	}

	return response, nil
}

func (t *httpTriggerer) Type() model.TriggerType {
	return model.TriggerTypeHTTP
}

func (t *httpTriggerer) Resolve(ctx context.Context, test model.Test, opts *TriggerOptions) (model.Test, error) {
	http := test.ServiceUnderTest.HTTP

	if http == nil {
		return test, fmt.Errorf("no settings provided for HTTP triggerer")
	}

	url, err := opts.Executor.ResolveStatement(WrapInQuotes(http.URL, "\""))

	if err != nil {
		return test, err
	}

	http.URL = url

	headers := []model.HTTPHeader{}
	for _, h := range http.Headers {
		h.Key, err = opts.Executor.ResolveStatement(WrapInQuotes(h.Key, "\""))
		if err != nil {
			return test, err
		}

		h.Value, err = opts.Executor.ResolveStatement(WrapInQuotes(h.Value, "\""))
		if err != nil {
			return test, err
		}

		headers = append(headers, h)
	}
	http.Headers = headers

	if http.Body != "" {
		http.Body, err = opts.Executor.ResolveStatement(WrapInQuotes(http.Body, "'"))
		if err != nil {
			return test, err
		}
	}

	http.Auth, err = resolveAuth(http.Auth, opts.Executor)
	if err != nil {
		return test, err
	}

	test.ServiceUnderTest.HTTP = http

	return test, nil
}

func resolveAuth(auth *model.HTTPAuthenticator, executor expression.Executor) (*model.HTTPAuthenticator, error) {
	if auth == nil {
		return nil, nil
	}

	updated, err := auth.Map(func(v string) (string, error) {
		resolved, err := executor.ResolveStatement(WrapInQuotes(v, "\""))
		if err != nil {
			return "", err
		}
		return resolved, nil
	})

	return &updated, err
}

func mapResp(resp *http.Response) model.HTTPResponse {
	var mappedHeaders []model.HTTPHeader
	for key, headers := range resp.Header {
		for _, val := range headers {
			val := model.HTTPHeader{
				Key:   key,
				Value: val,
			}
			mappedHeaders = append(mappedHeaders, val)
		}
	}
	var body string
	if b, err := io.ReadAll(resp.Body); err == nil {
		body = string(b)
	} else {
		fmt.Println(err)
	}

	return model.HTTPResponse{
		Status:     resp.Status,
		StatusCode: resp.StatusCode,
		Headers:    mappedHeaders,
		Body:       body,
	}
}