Revert recent API changes

OVERVIEW

- Revert "Allow overriding default http.Client"
- Revert "Set project-specific user agent, offer override"

REFERENCES

- 884e59f
- 26ac7b4
- GH-134
- GH-135
- GH-139

README.md

@@ -27,7 +27,6 @@ A package to send messages to Microsoft Teams (channels)
     - [How to create a webhook URL (Connector)](#how-to-create-a-webhook-url-connector)
   - [Examples](#examples)
     - [Basic](#basic)
-    - [Set custom user agent](#set-custom-user-agent)
     - [Add an Action](#add-an-action)
     - [Disable webhook URL prefix validation](#disable-webhook-url-prefix-validation)
     - [Enable custom patterns' validation](#enable-custom-patterns-validation)
@@ -70,8 +69,6 @@ information.
     validation behavior
 - Configurable timeouts
 - Configurable retry support
-- Support for overriding the default `http.Client`
-- Support for overriding default project-specific user agent
 
 ## Project Status
 
@@ -187,12 +184,6 @@ This is an example of a simple client application which uses this library.
 
 File: [basic](./examples/basic/main.go)
 
-#### Set custom user agent
-
-This example illustrates setting a custom user agent.
-
-File: [custom-user-agent](./examples/custom-user-agent/main.go)
-
 #### Add an Action
 
 This example illustrates adding an [`OpenUri Action`][msgcard-ref-actions] to

doc.go

@@ -33,10 +33,6 @@ FEATURES
 
 • Configurable retry support
 
-• Support for overriding the default http.Client
-
-• Support for overriding the default project-specific user agent
-
 
 USAGE
 

send.go

@@ -69,14 +69,6 @@ const ExpectedWebhookURLResponseText string = "1"
 // before it times out and is cancelled.
 const DefaultWebhookSendTimeout = 5 * time.Second
 
-// DefaultUserAgent is the project-specific user agent used when submitting
-// messages unless overridden by client code. This replaces the Go default
-// user agent value of "Go-http-client/1.1".
-//
-// The major.minor numbers reflect when this project first diverged from the
-// "upstream" or parent project.
-const DefaultUserAgent string = "go-teams-notify/2.2"
-
 // ErrWebhookURLUnexpected is returned when a provided webhook URL does
 // not match a set of confirmed webhook URL patterns.
 var ErrWebhookURLUnexpected = errors.New("webhook URL does not match one of expected patterns")
@@ -97,16 +89,13 @@ type API interface {
 	Send(webhookURL string, webhookMessage MessageCard) error
 	SendWithContext(ctx context.Context, webhookURL string, webhookMessage MessageCard) error
 	SendWithRetry(ctx context.Context, webhookURL string, webhookMessage MessageCard, retries int, retriesDelay int) error
-	SetHTTPClient(httpClient *http.Client) API
-	SetUserAgent(userAgent string) API
 	SkipWebhookURLValidationOnSend(skip bool) API
 	AddWebhookURLValidationPatterns(patterns ...string) API
 	ValidateWebhook(webhookURL string) error
 }
 
 type teamsClient struct {
 	httpClient                   *http.Client
-	userAgent                    string
 	webhookURLValidationPatterns []string
 	skipWebhookURLValidation     bool
 }
@@ -144,22 +133,6 @@ func NewClient() API {
 	return &client
 }
 
-// SetHTTPClient accepts a custom http.Client value which replaces the
-// existing default http.Client.
-func (c *teamsClient) SetHTTPClient(httpClient *http.Client) API {
-	c.httpClient = httpClient
-
-	return c
-}
-
-// SetUserAgent accepts a custom user agent string. This custom user agent is
-// used when submitting messages to Microsoft Teams.
-func (c *teamsClient) SetUserAgent(userAgent string) API {
-	c.userAgent = userAgent
-
-	return c
-}
-
 // AddWebhookURLValidationPatterns collects given patterns for validation of
 // the webhook URL.
 func (c *teamsClient) AddWebhookURLValidationPatterns(patterns ...string) API {
@@ -340,14 +313,6 @@ func (c teamsClient) prepareRequest(ctx context.Context, webhookURL string, prep
 
 	req.Header.Add("Content-Type", "application/json;charset=utf-8")
 
-	// If provided, override the project-specific user agent with custom value.
-	switch {
-	case c.userAgent != "":
-		req.Header.Set("User-Agent", c.userAgent)
-	default:
-		req.Header.Set("User-Agent", DefaultUserAgent)
-	}
-
 	return req, nil
 }