Add URL path templating support with validation and documentation

README.md

@@ -74,18 +74,6 @@ Send 10,000 GET requests with 50 concurrent connections and a random User-Agent
 sarin -U http://example.com -r 10_000 -c 50 -H "User-Agent: {{ fakeit_UserAgent }}"
 ```
 
-Example output:
-
-```
-┌──────────┬───────┬──────────┬───────────┬─────────┬───────────┬──────────┬───────────┐
-│ Response │ Count │ Min      │ Max       │ Average │ P90       │ P95      │ P99       │
-├──────────┼───────┼──────────┼───────────┼─────────┼───────────┼──────────┼───────────┤
-│ 200      │ 10000 │ 78.038ms │ 288.153ms │ 94.71ms │ 103.078ms │ 131.08ms │ 269.218ms │
-├──────────┼───────┼──────────┼───────────┼─────────┼───────────┼──────────┼───────────┤
-│ Total    │ 10000 │ 78.038ms │ 288.153ms │ 94.71ms │ 103.078ms │ 131.08ms │ 269.218ms │
-└──────────┴───────┴──────────┴───────────┴─────────┴───────────┴──────────┴───────────┘
-```
-
 Run a 5-minute duration-based test:
 
 ```sh
@@ -112,15 +100,15 @@ For detailed documentation on all configuration options (URL, method, timeout, c
 
 ## Templating
 
-Sarin supports Go templates in methods, bodies, headers, params, cookies, and values. Use the 320+ built-in functions to generate dynamic data for each request.
+Sarin supports Go templates in URL paths, methods, bodies, headers, params, cookies, and values. Use the 320+ built-in functions to generate dynamic data for each request.
 
 **Example:**
 
 ```sh
-sarin -U http://example.com/users \
+sarin -U "http://example.com/users/{{ fakeit_UUID }}" -r 1000 -c 10 \
-  -V "ID={{ fakeit_UUID }}" \
+  -V "RequestID={{ fakeit_UUID }}" \
-  -H "X-Request-ID: {{ .Values.ID }}" \
+  -H "X-Request-ID: {{ .Values.RequestID }}" \
-  -B '{"id": "{{ .Values.ID }}"}'
+  -B '{"request_id": "{{ .Values.RequestID }}"}'
 ```
 
 For the complete templating guide and functions reference, see the **[Templating Guide](docs/templating.md)**.

docs/configuration.md

@@ -76,7 +76,21 @@ config3.yaml > config2.yaml > config4.yaml > config1.yaml
 
 ## URL
 
-Target URL. Must be HTTP or HTTPS.
+Target URL. Must be HTTP or HTTPS. The URL path supports [templating](templating.md), allowing dynamic path generation per request.
+
+> **Note:** Templating is only supported in the URL path. Host and scheme must be static.
+
+**Example with dynamic path:**
+
+```yaml
+url: http://example.com/users/{{ fakeit_UUID }}/profile
+```
+
+**CLI example with dynamic path:**
+
+```sh
+sarin -U "http://example.com/users/{{ fakeit_UUID }}" -r 1000 -c 10
+```
 
 ## Method
 

docs/examples.md

@@ -6,8 +6,8 @@ This guide provides practical examples for common Sarin use cases.
 
 - [Basic Usage](#basic-usage)
 - [Request-Based vs Duration-Based Tests](#request-based-vs-duration-based-tests)
-- [Dynamic Requests with Templating](#dynamic-requests-with-templating)
 - [Headers, Cookies, and Parameters](#headers-cookies-and-parameters)
+- [Dynamic Requests with Templating](#dynamic-requests-with-templating)
 - [Request Bodies](#request-bodies)
 - [Using Proxies](#using-proxies)
 - [Output Formats](#output-formats)
@@ -108,104 +108,6 @@ concurrency: 100
 
 </details>
 
-## Dynamic Requests with Templating
-
-Generate a random User-Agent for each request:
-
-```sh
-sarin -U http://example.com -r 1000 -c 10 \
-  -H "User-Agent: {{ fakeit_UserAgent }}"
-```
-
-<details>
-<summary>YAML equivalent</summary>
-
-```yaml
-url: http://example.com
-requests: 1000
-concurrency: 10
-headers:
-    User-Agent: "{{ fakeit_UserAgent }}"
-```
-
-</details>
-
-Send requests with random user data:
-
-```sh
-sarin -U http://example.com/api/users -r 1000 -c 10 \
-  -M POST \
-  -H "Content-Type: application/json" \
-  -B '{"name": "{{ fakeit_Name }}", "email": "{{ fakeit_Email }}"}'
-```
-
-<details>
-<summary>YAML equivalent</summary>
-
-```yaml
-url: http://example.com/api/users
-requests: 1000
-concurrency: 10
-method: POST
-headers:
-    Content-Type: application/json
-body: '{"name": "{{ fakeit_Name }}", "email": "{{ fakeit_Email }}"}'
-```
-
-</details>
-
-Use values to share generated data across headers and body:
-
-```sh
-sarin -U http://example.com/api/users -r 1000 -c 10 \
-  -M POST \
-  -V "ID={{ fakeit_UUID }}" \
-  -H "X-Request-ID: {{ .Values.ID }}" \
-  -B '{"id": "{{ .Values.ID }}", "name": "{{ fakeit_Name }}"}'
-```
-
-<details>
-<summary>YAML equivalent</summary>
-
-```yaml
-url: http://example.com/api/users
-requests: 1000
-concurrency: 10
-method: POST
-values: "ID={{ fakeit_UUID }}"
-headers:
-    X-Request-ID: "{{ .Values.ID }}"
-body: '{"id": "{{ .Values.ID }}", "name": "{{ fakeit_Name }}"}'
-```
-
-</details>
-
-Generate random IPs and timestamps:
-
-```sh
-sarin -U http://example.com/api/logs -r 500 -c 20 \
-  -M POST \
-  -H "Content-Type: application/json" \
-  -B '{"ip": "{{ fakeit_IPv4Address }}", "timestamp": "{{ fakeit_Date }}", "action": "{{ fakeit_HackerVerb }}"}'
-```
-
-<details>
-<summary>YAML equivalent</summary>
-
-```yaml
-url: http://example.com/api/logs
-requests: 500
-concurrency: 20
-method: POST
-headers:
-    Content-Type: application/json
-body: '{"ip": "{{ fakeit_IPv4Address }}", "timestamp": "{{ fakeit_Date }}", "action": "{{ fakeit_HackerVerb }}"}'
-```
-
-</details>
-
-> For the complete list of 320+ template functions, see the **[Templating Guide](templating.md)**.
-
 ## Headers, Cookies, and Parameters
 
 **Custom headers:**
@@ -323,6 +225,140 @@ cookies:
 
 </details>
 
+## Dynamic Requests with Templating
+
+**Dynamic URL paths:**
+
+Test different resource endpoints with random IDs:
+
+```sh
+sarin -U "http://example.com/users/{{ fakeit_UUID }}/profile" -r 1000 -c 10
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com/users/{{ fakeit_UUID }}/profile
+requests: 1000
+concurrency: 10
+```
+
+</details>
+
+Test with random numeric IDs:
+
+```sh
+sarin -U "http://example.com/products/{{ fakeit_Number 1 10000 }}" -r 1000 -c 10
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com/products/{{ fakeit_Number 1 10000 }}
+requests: 1000
+concurrency: 10
+```
+
+</details>
+
+**Generate a random User-Agent for each request:**
+
+```sh
+sarin -U http://example.com -r 1000 -c 10 \
+  -H "User-Agent: {{ fakeit_UserAgent }}"
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com
+requests: 1000
+concurrency: 10
+headers:
+    User-Agent: "{{ fakeit_UserAgent }}"
+```
+
+</details>
+
+Send requests with random user data:
+
+```sh
+sarin -U http://example.com/api/users -r 1000 -c 10 \
+  -M POST \
+  -H "Content-Type: application/json" \
+  -B '{"name": "{{ fakeit_Name }}", "email": "{{ fakeit_Email }}"}'
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com/api/users
+requests: 1000
+concurrency: 10
+method: POST
+headers:
+    Content-Type: application/json
+body: '{"name": "{{ fakeit_Name }}", "email": "{{ fakeit_Email }}"}'
+```
+
+</details>
+
+Use values to share generated data across headers and body:
+
+```sh
+sarin -U http://example.com/api/users -r 1000 -c 10 \
+  -M POST \
+  -V "ID={{ fakeit_UUID }}" \
+  -H "X-Request-ID: {{ .Values.ID }}" \
+  -B '{"id": "{{ .Values.ID }}", "name": "{{ fakeit_Name }}"}'
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com/api/users
+requests: 1000
+concurrency: 10
+method: POST
+values: "ID={{ fakeit_UUID }}"
+headers:
+    X-Request-ID: "{{ .Values.ID }}"
+body: '{"id": "{{ .Values.ID }}", "name": "{{ fakeit_Name }}"}'
+```
+
+</details>
+
+Generate random IPs and timestamps:
+
+```sh
+sarin -U http://example.com/api/logs -r 500 -c 20 \
+  -M POST \
+  -H "Content-Type: application/json" \
+  -B '{"ip": "{{ fakeit_IPv4Address }}", "timestamp": "{{ fakeit_Date }}", "action": "{{ fakeit_HackerVerb }}"}'
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com/api/logs
+requests: 500
+concurrency: 20
+method: POST
+headers:
+    Content-Type: application/json
+body: '{"ip": "{{ fakeit_IPv4Address }}", "timestamp": "{{ fakeit_Date }}", "action": "{{ fakeit_HackerVerb }}"}'
+```
+
+</details>
+
+> For the complete list of 320+ template functions, see the **[Templating Guide](templating.md)**.
+
 ## Request Bodies
 
 **Simple JSON body:**

docs/templating.md

@@ -1,6 +1,8 @@
 # Templating
 
-Sarin supports Go templates in methods, bodies, headers, params, cookies, and values.
+Sarin supports Go templates in URL paths, methods, bodies, headers, params, cookies, and values.
+
+> **Note:** Templating in URL host and scheme is not supported. Only the path portion of the URL can contain templates.
 
 ## Table of Contents
 

internal/config/template_validator.go

@@ -180,6 +180,15 @@ func validateTemplateValues(values []string, funcMap template.FuncMap) []types.F
 	return validationErrors
 }
 
+func validateTemplateURLPath(urlPath string, funcMap template.FuncMap) []types.FieldValidationError {
+	if err := validateTemplateString(urlPath, funcMap); err != nil {
+		return []types.FieldValidationError{
+			types.NewFieldValidationError("URL.Path", urlPath, err),
+		}
+	}
+	return nil
+}
+
 func ValidateTemplates(config *Config) []types.FieldValidationError {
 	// Create template function map using the same functions as sarin package
 	randSource := sarin.NewDefaultRandSource()
@@ -190,6 +199,11 @@ func ValidateTemplates(config *Config) []types.FieldValidationError {
 
 	var allErrors []types.FieldValidationError
 
+	// Validate URL path
+	if config.URL != nil {
+		allErrors = append(allErrors, validateTemplateURLPath(config.URL.Path, funcMap)...)
+	}
+
 	// Validate methods
 	allErrors = append(allErrors, validateTemplateMethods(config.Methods, funcMap)...)
 

internal/sarin/request.go

@@ -40,6 +40,7 @@ func NewRequestGenerator(
 	localRand := rand.New(randSource)
 	templateFuncMap := NewDefaultTemplateFuncMap(randSource)
 
+	pathGenerator, isPathGeneratorDynamic := createTemplateFunc(requestURL.Path, templateFuncMap)
 	methodGenerator, isMethodGeneratorDynamic := NewMethodGeneratorFunc(localRand, methods, templateFuncMap)
 	paramsGenerator, isParamsGeneratorDynamic := NewParamsGeneratorFunc(localRand, params, templateFuncMap)
 	headersGenerator, isHeadersGeneratorDynamic := NewHeadersGeneratorFunc(localRand, headers, templateFuncMap)
@@ -51,35 +52,45 @@ func NewRequestGenerator(
 
 	valuesGenerator := NewValuesGeneratorFunc(values, templateFuncMap)
 
+	var (
+		data valuesData
+		path string
+		err  error
+	)
 	return func(req *fasthttp.Request) error {
-			req.SetRequestURI(requestURL.Path)
 			req.Header.SetHost(requestURL.Host)
 
-			data, err := valuesGenerator()
+			data, err = valuesGenerator()
 			if err != nil {
 				return err
 			}
 
-			if err := methodGenerator(req, data); err != nil {
+			path, err = pathGenerator(data)
+			if err != nil {
+				return err
+			}
+			req.SetRequestURI(path)
+
+			if err = methodGenerator(req, data); err != nil {
 				return err
 			}
 
 			bodyTemplateFuncMapData.ClearFormDataContenType()
-			if err := bodyGenerator(req, data); err != nil {
+			if err = bodyGenerator(req, data); err != nil {
 				return err
 			}
 
-			if err := headersGenerator(req, data); err != nil {
+			if err = headersGenerator(req, data); err != nil {
 				return err
 			}
 			if bodyTemplateFuncMapData.GetFormDataContenType() != "" {
 				req.Header.Add("Content-Type", bodyTemplateFuncMapData.GetFormDataContenType())
 			}
 
-			if err := paramsGenerator(req, data); err != nil {
+			if err = paramsGenerator(req, data); err != nil {
 				return err
 			}
-			if err := cookiesGenerator(req, data); err != nil {
+			if err = cookiesGenerator(req, data); err != nil {
 				return err
 			}
 
@@ -87,7 +98,8 @@ func NewRequestGenerator(
 				req.URI().SetScheme("https")
 			}
 			return nil
-		}, isMethodGeneratorDynamic ||
+		}, isPathGeneratorDynamic ||
+			isMethodGeneratorDynamic ||
 			isParamsGeneratorDynamic ||
 			isHeadersGeneratorDynamic ||
 			isCookiesGeneratorDynamic ||