java.lang.Object
- com.fnproject.fn.testing.FnTestingRule

All Implemented Interfaces:: org.junit.rules.TestRule

public final class FnTestingRule
extends Object
implements org.junit.rules.TestRule

Testing Rule for fn Java FDK functions.

This interface facilitates:

The creation of an in-memory environment replicating the functionality of the fn service
The creation of input events passed to a user function using givenEvent()
The verification of function behaviour by accessing output represented by FnResult instances.

Example Usage:


 public class MyFunctionTest {
     {@literal @}Rule
     public final FnTestingRule testing = FnTestingRule.createDefault();

     {@literal @}Test
     public void myTest() {
         // Create an event to invoke MyFunction and put it into the event queue
         fn.givenEvent()
            .addHeader("FOO", "BAR")
            .withBody("Body")
            .enqueue();

         // Run MyFunction#handleRequest using the built event queue from above
         fn.thenRun(MyFunction.class, "handleRequest");

         // Get the function result and check it for correctness
         FnResult result = fn.getOnlyResult();
         assertThat(result.getStatus()).isEqualTo(200);
         assertThat(result.getBodyAsString()).isEqualTo("expected return value of my function");
     }
 }

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`FnTestingRule.TestCodec`
`static class`	`FnTestingRule.TestOutput` TestOutput represents an output of a function it wraps OutputEvent and provides buffered access to the function output

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addFeature(FnTestingRuleFeature f)`
`FnTestingRule`	`addSharedClass(Class<?> cls)` Add a class to be forked during the test.
`FnTestingRule`	`addSharedClassPrefix(String prefix)` Add a class or package name to be forked during the test.
`org.junit.runners.model.Statement`	`apply(org.junit.runners.model.Statement base, org.junit.runner.Description description)`
`static FnTestingRule`	`createDefault()` Create an instance of the testing `Rule`, with Flows support
`Map<String,String>`	`getConfig()`
`Map<String,String>`	`getEventEnv()`
`int`	`getLastExitCode()` Get the exit code from the most recent invocation 0 = success 1 = failed 2 = not run due to initialization error
`FnResult`	`getOnlyResult()` Convenience method to get the one and only parsed http response expected on the output of the function
`List<FnResult>`	`getResults()` Parses any pending HTTP responses on the functions output stream and returns the corresponding FnResult instances
`List<String>`	`getSharedPrefixes()`
`byte[]`	`getStdErr()` Get the StdErr stream returned by the function as a byte array
`String`	`getStdErrAsString()` Gets the StdErr stream returned by the function as a String
`FnEventBuilderJUnit4`	`givenEvent()` Create an HTTP event builder for the function
`FnTestingRule`	`setConfig(String key, String value)` Add a config variable to the function for the test
`void`	`thenRun(Class<?> cls, String method)` Runs the function runtime with the specified class and method (and waits for Flow stages to finish if the test spawns any flows)
`void`	`thenRun(String cls, String method)` Runs the function runtime with the specified class and method (and waits for Flow stages to finish if the test spawns any Flow)

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - addFeature
```
public void addFeature(FnTestingRuleFeature f)
```
  - createDefault
```
public static FnTestingRule createDefault()
```
    Create an instance of the testing Rule, with Flows support
    
    Returns:
    
    a new test rule
  - setConfig
```
public FnTestingRule setConfig(String key,
                               String value)
```
    Add a config variable to the function for the test
    Config names will be translated to upper case with hyphens and spaces translated to _. Clashing config keys will be overwritten.
    
    Parameters:
    
    key - the configuration key
    
    value - the configuration value
    
    Returns:
    
    the current test rule
  - addSharedClassPrefix
```
public FnTestingRule addSharedClassPrefix(String prefix)
```
    Add a class or package name to be forked during the test. The test will be run under the aegis of a classloader that duplicates the class hierarchy named.
    
    Parameters:
    
    prefix - A class name or package prefix, such as "com.example.foo."
  - addSharedClass
```
public FnTestingRule addSharedClass(Class<?> cls)
```
    Add a class to be forked during the test. The test will be run under the aegis of a classloader that duplicates the class hierarchy named.
    
    Parameters:
    
    cls - A class
  - apply
```
public org.junit.runners.model.Statement apply(org.junit.runners.model.Statement base,
                                               org.junit.runner.Description description)
```
    Specified by:
    
    apply in interface org.junit.rules.TestRule
  - givenEvent
```
public FnEventBuilderJUnit4 givenEvent()
```
    Create an HTTP event builder for the function
    
    Returns:
    
    a new event builder
  - thenRun
```
public void thenRun(Class<?> cls,
                    String method)
```
    Runs the function runtime with the specified class and method (and waits for Flow stages to finish if the test spawns any flows)
    
    Parameters:
    
    cls - class to thenRun
    
    method - the method name
  - thenRun
```
public void thenRun(String cls,
                    String method)
```
    Runs the function runtime with the specified class and method (and waits for Flow stages to finish if the test spawns any Flow)
    
    Parameters:
    
    cls - class to thenRun
    
    method - the method name
  - getLastExitCode
```
public int getLastExitCode()
```
    Get the exit code from the most recent invocation 0 = success 1 = failed 2 = not run due to initialization error
  - getStdErr
```
public byte[] getStdErr()
```
    Get the StdErr stream returned by the function as a byte array
    
    Returns:
    
    the StdErr stream as bytes from the runtime
  - getStdErrAsString
```
public String getStdErrAsString()
```
    Gets the StdErr stream returned by the function as a String
    
    Returns:
    
    the StdErr stream as a string from the function
  - getResults
```
public List<FnResult> getResults()
```
    Parses any pending HTTP responses on the functions output stream and returns the corresponding FnResult instances
    
    Returns:
    
    a list of Parsed HTTP responses (as FnResults) from the function runtime output
  - getOnlyResult
```
public FnResult getOnlyResult()
```
    Convenience method to get the one and only parsed http response expected on the output of the function
    
    Returns:
    
    a single parsed HTTP response from the function runtime output
    
    Throws:
    
    IllegalStateException - if zero or more than one responses were produced
  - getSharedPrefixes
```
public List<String> getSharedPrefixes()
```
  - getConfig
```
public Map<String,String> getConfig()
```
  - getEventEnv
```
public Map<String,String> getEventEnv()
```

Class FnTestingRule

Example Usage:

Nested Class Summary

Method Summary

Methods inherited from class java.lang.Object

Method Detail

addFeature

createDefault

setConfig

addSharedClassPrefix

addSharedClass

apply

givenEvent

thenRun

thenRun

getLastExitCode

getStdErr

getStdErrAsString

getResults

getOnlyResult

getSharedPrefixes

getConfig

getEventEnv