tests/README.md - trafficserver - Git at Google


 # Getting Started

 This directory contains different tests for Apache Trafficserver. It is recommended that all tests move to this common area under the correct location based on the type of test being added.

 ## Layout
 The current layout is:

 **gold_tests/** - contains all the tests that run on the Reusable Gold Testing System (AuTest)

 **tools/** - contains programs used to help with testing.

 **include/** - contains headers used for unit testing.


 # Basic setup

 To enable autests, you need to set the ENABLE_AUTESTS cmake variable.  You can add this to your build with:

     $ cmake -B build -DENABLE_AUTEST=ON

 This will turn on building the autest plugins and helper tools as well as create an `autest` target.

 # Running tests

 Running the tests can be done using the `autest` target

     $ cmake --build build -t autest

 This will build ATS, install it to a temporary directory, setup the virtual environment via uv, and run all of the autests.

 To run autest again, or to run individual tests, the cmake build generates a helper script in the build directory at
 `<build>/tests/autest.sh`.  This script can be used to run individual tests and further configure autest.

 To run a single test, you can use the `--filter` flag to name
 which test to run. The tests are in files whose names are the test name
 , and are suffixed with `.test.py`. Thus, the `something_descriptive`
 test will be specified in a file named `something_descriptive.test.py`.
 The corresponding `autest.sh` command is:

     $ ./autest.sh --filter=something_descriptive

 # Running tests in parallel

 For faster test execution, a parallel test runner is available that distributes
 tests across multiple workers. This is especially useful on machines with many
 CPU cores.

     $ python3 autest-parallel.py -j 16 --ats-bin <install>/bin --build-root <build-dir> --sandbox /tmp/autest-parallel

 Key options:

 * `-j N` - Number of parallel workers (default: number of CPU cores)
 * `--ats-bin` - Path to the ATS install bin directory
 * `--build-root` - Path to the build directory (for test plugins)
 * `--sandbox` - Directory for test sandboxes (default: `/tmp/autest-parallel`)
 * `-v` - Verbose output with real-time test progress per worker
 * `--collect-timings` - Collect per-test timing data from each worker batch
 * `--list` - List all tests and exit (useful for checking test discovery)

 The parallel runner uses port offsets to ensure each worker gets a unique port
 range, preventing conflicts between concurrent test instances. Tests known to
 require serial execution (listed in `serial_tests.txt`) are run sequentially
 after the parallel phase completes.

 ## Timing-based load balancing

 If a `test-timings.json` file exists (generated by a previous run with
 `--collect-timings`), the runner uses the Longest Processing Time (LPT)
 algorithm to distribute tests across workers for balanced execution times.
 Without timing data, tests are distributed round-robin.

 ## Adding serial tests

 If a test cannot run in parallel (e.g., it uses hardcoded global resources),
 add its path relative to `gold_tests/` to `serial_tests.txt`.

 # Advanced setup

 AuTest and the relevant tools can be install manually instead of using the wrapper script. By doing this, it is often easier to debug issues with the testing system, or the tests. There are two ways this can be done.
 1. Run the bootstrap script then source the path with a "source ./env-test/bin/activate" command. At this point autest command should run without the wrapper script
 2. Make sure you install python 3.6 or better on your system. From there install these python packages ( ie pip install ):
   - hyper
   - git+https://bitbucket.org/autestsuite/reusable-gold-testing-system.git
   - [traffic-replay](https://bitbucket.org/autestsuite/trafficreplay/src/master/) (This will automatically install [MicroDNS](https://bitbucket.org/autestsuite/microdns/src/master/), [MicroServer](https://bitbucket.org/autestsuite/microserver/src/master/), [TrafficReplayLibrary](https://bitbucket.org/autestsuite/trafficreplaylibrary/src/master/), and dnslib as part of the dependencies.)

 # Writing tests for AuTest
 When writing for the AuTest system please refer to the current [Online Documentation](https://autestsuite.bitbucket.io/) for general use of the system. To use CurlHeader tester for testing output of curl, please refer to [CurlHeader README](gold_tests/autest-site/readme.md)

 ## Documentation of AuTest extension for ATS.
 Autest allows for the creation of extensions to help specialize and simplify test writing for a given application domain. Minus API addition the extension code will check that python 3.6 or better is used. There is also a new command line argumented added specifically for Trafficserver:

 --ats-bin < path to bin directory >

 This command line argument will point to your build of ATS you want to test. At this time v6.0 or newer of Trafficserver should work.

 ### MakeATSProcess(name,command=[traffic_server], select_ports=[True], enable_tls=[False])
  * name - A name for this instance of ATS
  * command - optional argument defining what process to use. Defaults to traffic_server.
  * select_ports - have the testing system automatically select a nonSSL port to use for this instance of ATS
  * enable_tls - have the testing system also auto-select a SSL port to use (NOTE: This does not set up certs and other TLS-related configs.)

 This function will define a sandbox for an instance of trafficserver to run under. The function will return a AuTest process object that will have a number of files and variables define for making it easier to define a test. If both *select_ports* and *enable_tls* are toggled to **False**, then the test writer will be responsible for setting up the ports and the ready condition for an instance of ATS.

 #### Environment
 The environment of the process will have a number of added environment variables to control trafficserver running the in the sandbox location correctly. This can be used to easily setup other commands that should run under same environment.

 ##### Example

 ```python
 # Define default ATS
 ts=Test.MakeATSProcess("ts")
 # Call traffic_ctrl to set new generation
 tr=Test.AddTestRun()
 tr.Processes.Default.Command='traffic_ctl'
 tr.Processes.Default.ReturnCode=0
 # set the environment for traffic_control to run in to be the same as the "ts" ATS instance
 tr.Processes.Default.Env=ts.Env
 ```

 #### Variables
 These are the current variables that are defined dynamically for Trafficserver

 port - the ipv4 port to listen on
 portv6 - the ipv6 port to listen on
 admin_port - the admin port used. This is set even is select_port is False

 #### File objects
 A number of file objects are defined to help with adding values to a given configuration value to for a test, or testing a value exists in a log file. File that are defined currently are:

 ##### log files
  * squid.log
  * error.log
  * diags.log

 ##### config files
  * records.yaml
  * cache.config
  * hosting.config
  * ip_allow.yaml
  * logging.yaml
  * parent.config
  * plugin.config
  * remap.config
  * sni.yaml
  * socks.config
  * splitdns.config
  * ssl_multicert.config
  * storage.yaml

 #### Examples

 Create a server

 ```python
 # don't set ports because a config file will set them
 ts1 = Test.MakeATSProcess("ts1",select_ports=False)
 ts1.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml')
 ```

 Create a server and get the dynamic port value

 ```python
 # Define default ATS
 ts=Test.MakeATSProcess("ts")
 #first test is a miss for default
 tr=Test.AddTestRun()
 # get port for command from Variables
 tr.MakeCurlCommand('"http://127.0.0.1:{0}" --verbose'.format(ts.Variables.port), ts=ts)

 ```

 Add value to a configuration file
 ```python
 # setup some config file for this server
 ts.Disk.records_config.update({
             'proxy.config.body_factory.enable_customizations': 3,  # enable domain specific body factory
             'proxy.config.http.cache.generation':-1, # Start with cache turned off
             'proxy.config.config_update_interval_ms':1,
         })
 ts.Disk.plugin_config.AddLine('xdebug.so')
 ts.Disk.remap_config.AddLines([
             'map /default/ http://127.0.0.1/ @plugin=generator.so',
             #line 2
             'map /generation1/ http://127.0.0.1/' +
             ' @plugin=conf_remap.so @pparam=proxy.config.http.cache.generation=1' +
             ' @plugin=generator.so',
             #line 3
             'map /generation2/ http://127.0.0.1/' +
             ' @plugin=conf_remap.so @pparam=proxy.config.http.cache.generation=2' +
             ' @plugin=generator.so'
         ])
 ```

 ### CopyConfig(file, targetname=None, process=None)
 * file - name of the file to copy. Relative paths are relative from the test file location
 * targetname - the name name of the file when copied to the correct configuration location
 * process - optional process object to use for getting path location to copy to. Only needed if the Setup object call is not in the scope of the process object created with the MakeATSProcess(...) API.

 This function copies a given configuration file the location of a given trafficserver sandbox used in a test. Given a test might have more than on trafficserver instance, it can be difficult to understand the correct location to copy to. This function will deal with the details correctly.

 #### Examples

 Copy a file over

 ```python
 ts1 = Test.MakeATSProcess("ts1",select_ports=False)
 # uses the setup object in the scope of the process object
 ts1.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml')
 ```
 ```python
 ts1 = Test.MakeATSProcess("ts1",select_ports=False)
 # uses the Setup in the global process via a variable passing
 Test.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml',ts1)
 # same as above, but uses the dynamic object model form
 Test.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml',Test.Processes.ts1)
 ```

 ## Setting up Origin Server
 ### Test.MakeOriginServer(Name)
  * name - A name for this instance of Origin Server.

  This function returns a AuTest process object that launches the python-based microserver. Micro-Server is a mock server which responds to client http requests. Microserver needs to be setup for the tests that require an origin server behind ATS. The server reads a JSON-formatted data file that contains request headers and the corresponding response headers. Microserver responds with payload if the response header contains Content-Length or Transfer-Enconding specified.

 ### addResponse(filename, request_header, response_header)
 * filename - name of the file where the request header and response header will be written to in JSON format
 * request_header - dictionary of request header
 * response_header - dictionary of response header corresponding to the request header.

 This function adds the request header and response header to a file which is then read by the microserver to populate request-response map. The key-fields required for the header dictionary are 'headers', 'timestamp' and 'body'.

 ### Example
 ```python
 #create the origin server process
 server=Test.MakeOriginServer("server")
 #define the request header and the desired response header
 request_header={"headers": "GET / HTTP/1.1\r\nHost: www.example.com\r\n\r\n", "timestamp": "1469733493.993", "body": ""}
 #desired response form the origin server
 response_header={"headers": "HTTP/1.1 200 OK\r\nConnection: close\r\n\r\n", "timestamp": "1469733493.993", "body": ""}
 #addResponse adds the transaction to a file which is used by the server
 server.addResponse("sessionlog.json", request_header, response_header)
 #add remap rule to traffic server
 ts.Disk.remap_config.AddLine(
     'map http://www.example.com http://127.0.0.1:{0}'.format(server.Variables.Port)
 )
 ```

 ## Setting up DNS
 ### Test.MakeDNServer(name, default=None)
  * name - A name for this instance of the DNS.
  * default - if a list argument is provided, uDNS will reply with the list contents instead of NXDOMAIN if a DNS can't be found for a particular entry

  This function returns a AuTest process object that launches the python-based microDNS (uDNS). uDNS is a mock DNS which responds to DNS queries. uDNS needs to be setup for the tests that require made-up domains. The server reads a JSON-formatted data file that contains mappings of domain to IP addresses. uDNS responds with the appropriate IP addresses if the requested domain is in uDNS' mappings.

  * addRecords(records=None, jsonFile=None)

  This function adds records using either a dictionary, *records*, or a json file, *jsonFile*.

  The supplied dictionary must be in the form of ```{ 'domain A': [IP1, IP2], 'domain B': [IP3, IP4] }```.

  The supplied json file must take the form of
  ```
  {
      "mappings": [
          {domain A: [IP1, IP2]},
          {domain B: [IP3, IP4]}
      ]
  }
  ```

  ### Examples
  There are 3 ways to utilize uDNS -

  Easy way if everything is done on localhost - by adding default option to Test.MakeDNServer:
  *uDNS by default returns NXDOMAIN for any unknown mappings*

  ```python
     # create TrafficServer and uDNS processes
     ts = Test.MakeATSProcess("ts")
     dns = Test.MakeDNServer("dns", default=['127.0.0.1'])

     ts.Disk.records_config.update({
         'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port), # let TrafficServer know where the DNS is located
         'proxy.config.dns.resolv_conf': 'NULL',
         'proxy.config.url_remap.remap_required': 0  # need this so TrafficServer won't return error upon not finding the domain in its remap file
     })
  ```

  Using the *addRecords* method:
  ```python
     # create TrafficServer and uDNS processes
     ts = Test.MakeATSProcess("ts")
     dns = Test.MakeDNServer("dns")

     ts.Disk.records_config.update({
         'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port), # let TrafficServer know where the DNS is located
         'proxy.config.dns.resolv_conf': 'NULL',
         'proxy.config.url_remap.remap_required': 0  # need this so TrafficServer won't return error upon not finding the domain in its remap file
     })

     dns.addRecords(records={"foo.com.":["127.0.0.1", "127.0.1.1"]})
     # AND/OR
     dns.addRecords(jsonFile="zone.json") # where zone.json is in the format described above
  ```

  Without disabling remap_required:
  ```python
     # create TrafficServer and uDNS processes
     ts = Test.MakeATSProcess("ts")
     dns = Test.MakeDNServer("dns")

     ts.Disk.records_config.update({
         'proxy.config.dns.resolv_conf': 'NULL',
         'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port) # let TrafficServer know where the DNS is located
     })

     # if we don't disable remap_required, we can also just remap a domain to a domain recognized by DNS
     ts.Disk.remap_config.AddLine(
         'map http://example.com http://foo.com'
     )

     dns.addRecords(records={"foo.com.":["127.0.0.1", "127.0.1.1"]})
  ```

 ## Condition Testing
 ### Condition.HasATSFeature(feature)
  * feature - The feature to test for

  This function tests for Traffic server for possible feature it has been compiled with. Current Features you can test for are:
  * TS_HAS_LZMA
  * TS_HAS_PIPE_BUFFER_SIZE_CONFIG
  * TS_HAS_JEMALLOC
  * TS_HAS_MIMALLOC
  * TS_HAS_IN6_IS_ADDR_UNSPECIFIED
  * TS_HAS_BACKTRACE
  * TS_HAS_PROFILER
  * TS_USE_FAST_SDK
  * TS_USE_DIAGS
  * TS_USE_EPOLL
  * TS_USE_KQUEUE
  * TS_USE_POSIX_CAP
  * TS_USE_TPROXY
  * TS_HAS_SO_MARK
  * TS_HAS_IP_TOS
  * TS_USE_HWLOC
  * TS_USE_TLS13
  * TS_USE_QUIC
  * TS_HAS_QUICHE
  * TS_HAS_SO_PEERCRED
  * TS_USE_REMOTE_UNWINDING
  * TS_HAS_128BIT_CAS
  * TS_HAS_TESTS

 ### Condition.HasCurlFeature(feature)
  * feature - The feature to test for

  This function tests for Curl for possible feature it has been compiled with. Consult Curl documentation for feature set.

 ### Example
 ```python
 #create the origin server process
 Test.SkipUnless(
     Condition.HasCurlFeature('http2'),
 )
 ```

 ### Condition.PluginExists(pluginname)
  * pluginname - The plugin to test for

  This function tests for existence of a certain plugin in TrafficServer.

 ### Example
 ```python
 Test.SkipUnless(
     Condition.PluginExists('a-plugin.so'),
 )
 ```

	# Getting Started

	This directory contains different tests for Apache Trafficserver. It is recommended that all tests move to this common area under the correct location based on the type of test being added.

	## Layout
	The current layout is:

	gold_tests/ - contains all the tests that run on the Reusable Gold Testing System (AuTest)

	tools/ - contains programs used to help with testing.

	include/ - contains headers used for unit testing.


	# Basic setup

	To enable autests, you need to set the ENABLE_AUTESTS cmake variable. You can add this to your build with:

	$ cmake -B build -DENABLE_AUTEST=ON

	This will turn on building the autest plugins and helper tools as well as create an `autest` target.

	# Running tests

	Running the tests can be done using the `autest` target

	$ cmake --build build -t autest

	This will build ATS, install it to a temporary directory, setup the virtual environment via uv, and run all of the autests.

	To run autest again, or to run individual tests, the cmake build generates a helper script in the build directory at
	`<build>/tests/autest.sh`. This script can be used to run individual tests and further configure autest.

	To run a single test, you can use the `--filter` flag to name
	which test to run. The tests are in files whose names are the test name
	, and are suffixed with `.test.py`. Thus, the `something_descriptive`
	test will be specified in a file named `something_descriptive.test.py`.
	The corresponding `autest.sh` command is:

	$ ./autest.sh --filter=something_descriptive

	# Running tests in parallel

	For faster test execution, a parallel test runner is available that distributes
	tests across multiple workers. This is especially useful on machines with many
	CPU cores.

	$ python3 autest-parallel.py -j 16 --ats-bin <install>/bin --build-root <build-dir> --sandbox /tmp/autest-parallel

	Key options:

	* `-j N` - Number of parallel workers (default: number of CPU cores)
	* `--ats-bin` - Path to the ATS install bin directory
	* `--build-root` - Path to the build directory (for test plugins)
	* `--sandbox` - Directory for test sandboxes (default: `/tmp/autest-parallel`)
	* `-v` - Verbose output with real-time test progress per worker
	* `--collect-timings` - Collect per-test timing data from each worker batch
	* `--list` - List all tests and exit (useful for checking test discovery)

	The parallel runner uses port offsets to ensure each worker gets a unique port
	range, preventing conflicts between concurrent test instances. Tests known to
	require serial execution (listed in `serial_tests.txt`) are run sequentially
	after the parallel phase completes.

	## Timing-based load balancing

	If a `test-timings.json` file exists (generated by a previous run with
	`--collect-timings`), the runner uses the Longest Processing Time (LPT)
	algorithm to distribute tests across workers for balanced execution times.
	Without timing data, tests are distributed round-robin.

	## Adding serial tests

	If a test cannot run in parallel (e.g., it uses hardcoded global resources),
	add its path relative to `gold_tests/` to `serial_tests.txt`.

	# Advanced setup

	AuTest and the relevant tools can be install manually instead of using the wrapper script. By doing this, it is often easier to debug issues with the testing system, or the tests. There are two ways this can be done.
	1. Run the bootstrap script then source the path with a "source ./env-test/bin/activate" command. At this point autest command should run without the wrapper script
	2. Make sure you install python 3.6 or better on your system. From there install these python packages ( ie pip install ):
	- hyper
	- git+https://bitbucket.org/autestsuite/reusable-gold-testing-system.git
	- [traffic-replay](https://bitbucket.org/autestsuite/trafficreplay/src/master/) (This will automatically install [MicroDNS](https://bitbucket.org/autestsuite/microdns/src/master/), [MicroServer](https://bitbucket.org/autestsuite/microserver/src/master/), [TrafficReplayLibrary](https://bitbucket.org/autestsuite/trafficreplaylibrary/src/master/), and dnslib as part of the dependencies.)

	# Writing tests for AuTest
	When writing for the AuTest system please refer to the current [Online Documentation](https://autestsuite.bitbucket.io/) for general use of the system. To use CurlHeader tester for testing output of curl, please refer to [CurlHeader README](gold_tests/autest-site/readme.md)

	## Documentation of AuTest extension for ATS.
	Autest allows for the creation of extensions to help specialize and simplify test writing for a given application domain. Minus API addition the extension code will check that python 3.6 or better is used. There is also a new command line argumented added specifically for Trafficserver:

	--ats-bin < path to bin directory >

	This command line argument will point to your build of ATS you want to test. At this time v6.0 or newer of Trafficserver should work.

	### MakeATSProcess(name,command=[traffic_server], select_ports=[True], enable_tls=[False])
	* name - A name for this instance of ATS
	* command - optional argument defining what process to use. Defaults to traffic_server.
	* select_ports - have the testing system automatically select a nonSSL port to use for this instance of ATS
	* enable_tls - have the testing system also auto-select a SSL port to use (NOTE: This does not set up certs and other TLS-related configs.)

	This function will define a sandbox for an instance of trafficserver to run under. The function will return a AuTest process object that will have a number of files and variables define for making it easier to define a test. If both select_ports and enable_tls are toggled to False, then the test writer will be responsible for setting up the ports and the ready condition for an instance of ATS.

	#### Environment
	The environment of the process will have a number of added environment variables to control trafficserver running the in the sandbox location correctly. This can be used to easily setup other commands that should run under same environment.

	##### Example

	```python
	# Define default ATS
	ts=Test.MakeATSProcess("ts")
	# Call traffic_ctrl to set new generation
	tr=Test.AddTestRun()
	tr.Processes.Default.Command='traffic_ctl'
	tr.Processes.Default.ReturnCode=0
	# set the environment for traffic_control to run in to be the same as the "ts" ATS instance
	tr.Processes.Default.Env=ts.Env
	```

	#### Variables
	These are the current variables that are defined dynamically for Trafficserver

	port - the ipv4 port to listen on
	portv6 - the ipv6 port to listen on
	admin_port - the admin port used. This is set even is select_port is False

	#### File objects
	A number of file objects are defined to help with adding values to a given configuration value to for a test, or testing a value exists in a log file. File that are defined currently are:

	##### log files
	* squid.log
	* error.log
	* diags.log

	##### config files
	* records.yaml
	* cache.config
	* hosting.config
	* ip_allow.yaml
	* logging.yaml
	* parent.config
	* plugin.config
	* remap.config
	* sni.yaml
	* socks.config
	* splitdns.config
	* ssl_multicert.config
	* storage.yaml

	#### Examples

	Create a server

	```python
	# don't set ports because a config file will set them
	ts1 = Test.MakeATSProcess("ts1",select_ports=False)
	ts1.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml')
	```

	Create a server and get the dynamic port value

	```python
	# Define default ATS
	ts=Test.MakeATSProcess("ts")
	#first test is a miss for default
	tr=Test.AddTestRun()
	# get port for command from Variables
	tr.MakeCurlCommand('"http://127.0.0.1:{0}" --verbose'.format(ts.Variables.port), ts=ts)

	```

	Add value to a configuration file
	```python
	# setup some config file for this server
	ts.Disk.records_config.update({
	'proxy.config.body_factory.enable_customizations': 3, # enable domain specific body factory
	'proxy.config.http.cache.generation':-1, # Start with cache turned off
	'proxy.config.config_update_interval_ms':1,
	})
	ts.Disk.plugin_config.AddLine('xdebug.so')
	ts.Disk.remap_config.AddLines([
	'map /default/ http://127.0.0.1/ @plugin=generator.so',
	#line 2
	'map /generation1/ http://127.0.0.1/' +
	' @plugin=conf_remap.so @pparam=proxy.config.http.cache.generation=1' +
	' @plugin=generator.so',
	#line 3
	'map /generation2/ http://127.0.0.1/' +
	' @plugin=conf_remap.so @pparam=proxy.config.http.cache.generation=2' +
	' @plugin=generator.so'
	])
	```

	### CopyConfig(file, targetname=None, process=None)
	* file - name of the file to copy. Relative paths are relative from the test file location
	* targetname - the name name of the file when copied to the correct configuration location
	* process - optional process object to use for getting path location to copy to. Only needed if the Setup object call is not in the scope of the process object created with the MakeATSProcess(...) API.

	This function copies a given configuration file the location of a given trafficserver sandbox used in a test. Given a test might have more than on trafficserver instance, it can be difficult to understand the correct location to copy to. This function will deal with the details correctly.

	#### Examples

	Copy a file over

	```python
	ts1 = Test.MakeATSProcess("ts1",select_ports=False)
	# uses the setup object in the scope of the process object
	ts1.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml')
	```
	```python
	ts1 = Test.MakeATSProcess("ts1",select_ports=False)
	# uses the Setup in the global process via a variable passing
	Test.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml',ts1)
	# same as above, but uses the dynamic object model form
	Test.Setup.ts.CopyConfig('config/records_8090.yaml','records.yaml',Test.Processes.ts1)
	```

	## Setting up Origin Server
	### Test.MakeOriginServer(Name)
	* name - A name for this instance of Origin Server.

	This function returns a AuTest process object that launches the python-based microserver. Micro-Server is a mock server which responds to client http requests. Microserver needs to be setup for the tests that require an origin server behind ATS. The server reads a JSON-formatted data file that contains request headers and the corresponding response headers. Microserver responds with payload if the response header contains Content-Length or Transfer-Enconding specified.

	### addResponse(filename, request_header, response_header)
	* filename - name of the file where the request header and response header will be written to in JSON format
	* request_header - dictionary of request header
	* response_header - dictionary of response header corresponding to the request header.

	This function adds the request header and response header to a file which is then read by the microserver to populate request-response map. The key-fields required for the header dictionary are 'headers', 'timestamp' and 'body'.

	### Example
	```python
	#create the origin server process
	server=Test.MakeOriginServer("server")
	#define the request header and the desired response header
	request_header={"headers": "GET / HTTP/1.1\r\nHost: www.example.com\r\n\r\n", "timestamp": "1469733493.993", "body": ""}
	#desired response form the origin server
	response_header={"headers": "HTTP/1.1 200 OK\r\nConnection: close\r\n\r\n", "timestamp": "1469733493.993", "body": ""}
	#addResponse adds the transaction to a file which is used by the server
	server.addResponse("sessionlog.json", request_header, response_header)
	#add remap rule to traffic server
	ts.Disk.remap_config.AddLine(
	'map http://www.example.com http://127.0.0.1:{0}'.format(server.Variables.Port)
	)
	```

	## Setting up DNS
	### Test.MakeDNServer(name, default=None)
	* name - A name for this instance of the DNS.
	* default - if a list argument is provided, uDNS will reply with the list contents instead of NXDOMAIN if a DNS can't be found for a particular entry

	This function returns a AuTest process object that launches the python-based microDNS (uDNS). uDNS is a mock DNS which responds to DNS queries. uDNS needs to be setup for the tests that require made-up domains. The server reads a JSON-formatted data file that contains mappings of domain to IP addresses. uDNS responds with the appropriate IP addresses if the requested domain is in uDNS' mappings.

	* addRecords(records=None, jsonFile=None)

	This function adds records using either a dictionary, records, or a json file, jsonFile.

	The supplied dictionary must be in the form of ```{ 'domain A': [IP1, IP2], 'domain B': [IP3, IP4] }```.

	The supplied json file must take the form of
	```
	{
	"mappings": [
	{domain A: [IP1, IP2]},
	{domain B: [IP3, IP4]}
	]
	}
	```

	### Examples
	There are 3 ways to utilize uDNS -

	Easy way if everything is done on localhost - by adding default option to Test.MakeDNServer:
	uDNS by default returns NXDOMAIN for any unknown mappings

	```python
	# create TrafficServer and uDNS processes
	ts = Test.MakeATSProcess("ts")
	dns = Test.MakeDNServer("dns", default=['127.0.0.1'])

	ts.Disk.records_config.update({
	'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port), # let TrafficServer know where the DNS is located
	'proxy.config.dns.resolv_conf': 'NULL',
	'proxy.config.url_remap.remap_required': 0 # need this so TrafficServer won't return error upon not finding the domain in its remap file
	})
	```

	Using the addRecords method:
	```python
	# create TrafficServer and uDNS processes
	ts = Test.MakeATSProcess("ts")
	dns = Test.MakeDNServer("dns")

	ts.Disk.records_config.update({
	'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port), # let TrafficServer know where the DNS is located
	'proxy.config.dns.resolv_conf': 'NULL',
	'proxy.config.url_remap.remap_required': 0 # need this so TrafficServer won't return error upon not finding the domain in its remap file
	})

	dns.addRecords(records={"foo.com.":["127.0.0.1", "127.0.1.1"]})
	# AND/OR
	dns.addRecords(jsonFile="zone.json") # where zone.json is in the format described above
	```

	Without disabling remap_required:
	```python
	# create TrafficServer and uDNS processes
	ts = Test.MakeATSProcess("ts")
	dns = Test.MakeDNServer("dns")

	ts.Disk.records_config.update({
	'proxy.config.dns.resolv_conf': 'NULL',
	'proxy.config.dns.nameservers': '127.0.0.1:{0}'.format(dns.Variables.Port) # let TrafficServer know where the DNS is located
	})

	# if we don't disable remap_required, we can also just remap a domain to a domain recognized by DNS
	ts.Disk.remap_config.AddLine(
	'map http://example.com http://foo.com'
	)

	dns.addRecords(records={"foo.com.":["127.0.0.1", "127.0.1.1"]})
	```

	## Condition Testing
	### Condition.HasATSFeature(feature)
	* feature - The feature to test for

	This function tests for Traffic server for possible feature it has been compiled with. Current Features you can test for are:
	* TS_HAS_LZMA
	* TS_HAS_PIPE_BUFFER_SIZE_CONFIG
	* TS_HAS_JEMALLOC
	* TS_HAS_MIMALLOC
	* TS_HAS_IN6_IS_ADDR_UNSPECIFIED
	* TS_HAS_BACKTRACE
	* TS_HAS_PROFILER
	* TS_USE_FAST_SDK
	* TS_USE_DIAGS
	* TS_USE_EPOLL
	* TS_USE_KQUEUE
	* TS_USE_POSIX_CAP
	* TS_USE_TPROXY
	* TS_HAS_SO_MARK
	* TS_HAS_IP_TOS
	* TS_USE_HWLOC
	* TS_USE_TLS13
	* TS_USE_QUIC
	* TS_HAS_QUICHE
	* TS_HAS_SO_PEERCRED
	* TS_USE_REMOTE_UNWINDING
	* TS_HAS_128BIT_CAS
	* TS_HAS_TESTS

	### Condition.HasCurlFeature(feature)
	* feature - The feature to test for

	This function tests for Curl for possible feature it has been compiled with. Consult Curl documentation for feature set.

	### Example
	```python
	#create the origin server process
	Test.SkipUnless(
	Condition.HasCurlFeature('http2'),
	)
	```

	### Condition.PluginExists(pluginname)
	* pluginname - The plugin to test for

	This function tests for existence of a certain plugin in TrafficServer.

	### Example
	```python
	Test.SkipUnless(
	Condition.PluginExists('a-plugin.so'),
	)
	```