The Common Test Framework provides a high level operator interface for testing. It adds the following features to the Erlang/OTP Test Server:

When Common Test starts, it will automatically attempt to compile any suites included in the specified tests. If particular suites have been specified, only those suites will be compiled. If a particular test object directory has been specified (meaning all suites in this directory should be part of the test), Common Test runs make:all/1 in the directory to compile the suites.

If compilation should fail for one or more suites, the compilation errors are printed to tty and the operator is asked if the test run should proceed without the missing suites, or be aborted. If the operator chooses to proceed, it is noted in the HTML log which tests have missing suites.

Any help module (i.e. regular Erlang module with name not ending with "_SUITE") that resides in the same test object directory as a suite which is part of the test, will also be automatically compiled. A help module will not be mistaken for a test suite (unless it has a "_SUITE" name of course). All help modules in a particular test object directory are compiled no matter if all or only particular suites in the directory are part of the test.

If test suites or help modules include header files stored in other locations than the test directory, you may specify these include directories by means of the flag with , or the option with . In addition to this, an include path may be specified with an OS environment variable; . Example (bash):

$ export CT_INCLUDE_PATH=~testuser/common_suite_files/include:~testuser/common_lib_files/include

Common Test will pass all include directories (specified either with the flag/option, or the variable, or both) to the compiler.

It is also possible to specify include directories in test specifications (see below).

If the user wants to run all test suites for a test object (or OTP application) by specifying only the top directory (e.g. with the dir start flag/option), Common Test will primarily look for test suite modules in a subdirectory named test. If this subdirectory doesn't exist, the specified top directory is assumed to be the actual test directory, and test suites will be read from there instead.

It is possible to disable the automatic compilation feature by using the flag with , or the option with . With automatic compilation disabled, the user is responsible for compiling the test suite modules (and any help modules) before the test run. If the modules can not be loaded from the local file system during startup of Common Test, the user needs to pre-load the modules before starting the test. Common Test will only verify that the specified test suites exist (i.e. that they are, or can be, loaded). This is useful e.g. if the test suites are transferred and loaded as binaries via RPC from a remote node.

The ct_run program can be used for running tests from the OS command line, e.g.

Examples:

$ ct_run -config $CFGS/sys1.cfg $CFGS/sys2.cfg -dir $SYS1_TEST $SYS2_TEST

$ ct_run -userconfig ct_config_xml $CFGS/sys1.xml $CFGS/sys2.xml -dir $SYS1_TEST $SYS2_TEST

$ ct_run -suite $SYS1_TEST/setup_SUITE $SYS2_TEST/config_SUITE

$ ct_run -suite $SYS1_TEST/setup_SUITE -case start stop

$ ct_run -suite $SYS1_TEST/setup_SUITE -group installation -case start stop

It is also possible to combine the dir, suite and group/case flags. E.g, to run x_SUITE and y_SUITE in directory testdir:

$ ct_run -dir ./testdir -suite x_SUITE y_SUITE

This has the same effect as calling:

$ ct_run -suite ./testdir/x_SUITE ./testdir/y_SUITE

For more details on test case group execution, please see below.

Other flags that may be used with ct_run:

The ct_run program sets the exit status before shutting down. The following values are defined:

If auto-skipped test cases should not affect the exit status, you may change the default behaviour using start flag:

-exit_status ignore_config

For more information about the ct_run program, see the Reference Manual and the Installation chapter.

Common Test provides an Erlang API for running tests. The main (and most flexible) function for specifying and executing tests is called ct:run_test/1. This function takes the same start parameters as the ct_run program described above, only the flags are instead given as options in a list of key-value tuples. E.g. a test specified with ct_run like:

$ ct_run -suite ./my_SUITE -logdir ./results

is with ct:run_test/1 specified as:

1> ct:run_test([{suite,"./my_SUITE"},{logdir,"./results"}]).

The function returns the test result, represented by the tuple: {Ok,Failed,{UserSkipped,AutoSkipped}}, where each element is an integer. If test execution fails, the function returns the tuple: {error,Reason}, where the term Reason explains the failure.

For detailed documentation about ct:run_test/1, please see the ct manual page.

With the ct_run flag, or ct:run_test/1 option group, one or more test case groups can be specified, optionally in combination with specific test cases. The syntax for specifying groups is as follows (on the command line):

       [-case ]]]>

or (in the Erlang shell):

       ct:run_test([{group,GroupsNamesOrPaths}, {case,Cases}]).]]>

The group_names_or_paths parameter specifies either one or more group names and/or one or more group paths. At start up, Common Test will search for matching groups in the group definitions tree (i.e. the list returned from Suite:groups/0, please see the Test case groups chapter for details). Given a group name, say g, Common Test will search for all paths that lead to g. By path here we mean a sequence of nested groups, all of which have to be followed in order to get from the top level group to g. Actually, what Common Test needs to do in order to execute the test cases in group g, is to call the init_per_group/2 function for each group in the path to g, as well as all corresponding end_per_group/2 functions afterwards. The obvious reason for this is that the configuration of a test case in g (and its Config input data) depends on init_per_testcase(TestCase, Config) and its return value, which in turn depends on init_per_group(g, Config) and its return value, which in turn depends on init_per_group/2 of the group above g, etc, all the way up to the top level group.

As you may have already realized, this means that if there is more than one way to locate a group (and its test cases) in a path, the result of the group search operation is a number of tests, all of which will be performed. Common Test actually interprets a group specification that consists of a single name this way:

"Search and find all paths in the group definitions tree that lead to the specified group and, for each path, create a test which (1) executes all configuration functions in the path to the specified group, then (2) executes all - or all matching - test cases in this group, as well as (3) all - or all matching - test cases in all sub groups of the group".

It is also possible for the user to specify a specific group path with the group_names_or_paths parameter. With this type of specification it's possible to avoid execution of unwanted groups (in otherwise matching paths), and/or the execution of sub groups. The syntax of the group path is a list of group names in the path, e.g. on the command line:

$ ct_run -suite "./x_SUITE" -group [g1,g3,g4] -case tc1 tc5

or similarly in the Erlang shell (requires a list within the groups list):

1> ct:run_test([{suite,"./x_SUITE"}, {group,[[g1,g3,g4]]}, {testcase,[tc1,tc5]}]).

The last group in the specified path will be the terminating group in the test, i.e. no sub groups following this group will be executed. In the example above, g4 is the terminating group, hence Common Test will execute a test that calls all init configuration functions in the path to g4, i.e. g1..g3..g4. It will then call test cases tc1 and tc5 in g4 and finally all end configuration functions in order g4..g3..g1.

Note that the group path specification doesn't necessarily have to include all groups in the path to the terminating group. Common Test will search for all matching paths if given an incomplete group path.

Note also that it's possible to combine group names and group paths with the group_names_or_paths parameter. Each element is treated as an individual specification in combination with the cases parameter. See examples below.

Examples:

      -module(x_SUITE).
      ...
      %% The group definitions:      
      groups() ->
        [{top1,[],[tc11,tc12,
	           {sub11,[],[tc12,tc13]},
	           {sub12,[],[tc14,tc15,
			      {sub121,[],[tc12,tc16]}]}]},

         {top2,[],[{group,sub21},{group,sub22}]},
         {sub21,[],[tc21,{group,sub2X2}]},
         {sub22,[],[{group,sub221},tc21,tc22,{group,sub2X2}]},
         {sub221,[],[tc21,tc23]},
         {sub2X2,[],[tc21,tc24]}].
    

$ ct_run -suite "x_SUITE" -group all

1> ct:run_test([{suite,"x_SUITE"}, {group,all}]).

Two tests will be executed, one for all cases and all sub groups under top1, and one for all under top2. (We would get the same result with -group top1 top2, or {group,[top1,top2]}.

$ ct_run -suite "x_SUITE" -group top1

1> ct:run_test([{suite,"x_SUITE"}, {group,[top1]}]).

This will execute one test for all cases and sub groups under top1.

$ ct_run -suite "x_SUITE" -group top1 -case tc12

1> ct:run_test([{suite,"x_SUITE"}, {group,[top1]}, {testcase,[tc12]}]).

This will run a test that executes tc12 in top1 and any sub group under top1 where it can be found (sub11 and sub121).

$ ct_run -suite "x_SUITE" -group [top1] -case tc12

1> ct:run_test([{suite,"x_SUITE"}, {group,[[top1]]}, {testcase,[tc12]}]).

This will execute tc12 only in group top1.

$ ct_run -suite "x_SUITE" -group top1 -case tc16

1> ct:run_test([{suite,"x_SUITE"}, {group,[top1]}, {testcase,[tc16]}]).

This will search top1 and all its sub groups for tc16 and the result will be that this test case executes in group sub121. (The specific path: -group [sub121] or {group,[[sub121]]}, would have given us the same result in this example).

$ ct_run -suite "x_SUITE" -group sub12 [sub12]

1> ct:run_test([{suite,"x_SUITE"}, {group,[sub12,[sub12]]}]).

This will execute two tests, one that includes all cases and sub groups under sub12, and one with only the test cases in sub12.

$ ct_run -suite "x_SUITE" -group sub2X2

1> ct:run_test([{suite,"x_SUITE"}, {group,[sub2X2]}]).

In this example, Common Test will find and execute two tests, one for the path from top2 to sub2X2 via sub21, and one from top2 to sub2X2 via sub22.

$ ct_run -suite "x_SUITE" -group [sub21,sub2X2]

1> ct:run_test([{suite,"x_SUITE"}, {group,[[sub21,sub2X2]]}]).

Here, by specifying the unique path: top2 -> sub21 -> sub2X2, only one test is executed. The second possible path from top2 to sub2X2 (above) will be discarded.

$ ct_run -suite "x_SUITE" -group [sub22] -case tc22 tc21

1> ct:run_test([{suite,"x_SUITE"}, {group,[[sub22]]}, {testcase,[tc22,tc21]}]).

In this example only the test cases for sub22 will be executed, and in reverse order compared to the group definition.

If a test case that belongs to a group (according to the group definition), is executed without a group specification, i.e. simply by means of (command line):

$ ct_run -suite "my_SUITE" -case my_tc

or (Erlang shell):

1> ct:run_test([{suite,"my_SUITE"}, {testcase,my_tc}]).

then Common Test ignores the group definition and executes the test case in the scope of the test suite only (no group configuration functions are called).

The group specification feature, exactly as it has been presented in this section, can also be used in Test Specifications (with some extra features added). Please see below.

You can start Common Test in an interactive shell mode where no automatic testing is performed. Instead, in this mode, Common Test starts its utility processes, installs configuration data (if any), and waits for the user to call functions (typically test case support functions) from the Erlang shell.

The shell mode is useful e.g. for debugging test suites, for analysing and debugging the SUT during "simulated" test case execution, and for trying out various operations during test suite development.

To invoke the interactive shell mode, you can start an Erlang shell manually and call ct:install/1 to install any configuration data you might need (use [] as argument otherwise), then call ct:start_interactive/0 to start Common Test. If you use the ct_run program, you may start the Erlang shell and Common Test in the same go by using the -shell and, optionally, the -config and/or -userconfig flag. Examples:

If no config file is given with the ct_run command, a warning will be displayed. If Common Test has been run from the same directory earlier, the same config file(s) will be used again. If Common Test has not been run from this directory before, no config files will be available.

If any functions using "required config data" (e.g. ct_telnet or ct_ftp functions) are to be called from the erlang shell, config data must first be required with ct:require/1/2. This is equivalent to a require statement in the Test Suite Info Function or in the Test Case Info Function.

Example:

 
       1> ct:require(unix_telnet, unix).
       ok
       2> ct_telnet:open(unix_telnet).
       {ok,<0.105.0>}
       4> ct_telnet:cmd(unix_telnet, "ls .").
       {ok,["ls .","file1  ...",...]}
    

Everything that Common Test normally prints in the test case logs, will in the interactive mode be written to a log named ctlog.html in the ]]> directory. A link to this file will be available in the file named last_interactive.html in the directory from which you executed ct_run. Currently, specifying a different root directory for the logs than the current working directory, is not supported.

If you wish to exit the interactive mode (e.g. to start an automated test run with ct:run_test/1), call the function ct:stop_interactive/0. This shuts down the running ct application. Associations between configuration names and data created with require are consequently deleted. ct:start_interactive/0 will get you back into interactive mode, but the previous state is not restored.

By means of ct_run -step [opts], or by passing the {step,Opts} option to ct:run_test/1, it is possible to get the Erlang Debugger started automatically and use its graphical interface to investigate the state of the current test case and to execute it step by step and/or set execution breakpoints.

If no extra options are given with the step flag/option, breakpoints will be set automatically on the test cases that are to be executed by Common Test, and those functions only. If the step option config is specified, breakpoints will also be initially set on the configuration functions in the suite, i.e. init_per_suite/1, end_per_suite/1, init_per_group/2, end_per_group/2, init_per_testcase/2 and end_per_testcase/2.

Common Test enables the Debugger auto attach feature, which means that for every new interpreted test case function that starts to execute, a new trace window will automatically pop up. (This is because each test case executes on a dedicated Erlang process). Whenever a new test case starts, Common Test will attempt to close the inactive trace window of the previous test case. However, if you prefer that Common Test leaves inactive trace windows, use the keep_inactive option.

The step functionality can be used together with the suite and the suite + case/testcase flag/option, but not together with dir.

	%% In specification file "a.spec"
	{specs, join, ["b.spec", "c.spec"]}.
	{specs, separate, ["d.spec", "e.spec"]}.
	%% Config and test terms follow
	...

Config terms:

	{merge_tests, Bool}.
	
	{define, Constant, Value}.
	
	{specs, InclSpecsOption, TestSpecs}.
	
	{node, NodeAlias, Node}.
	
	{init, InitOptions}.
	{init, [NodeAlias], InitOptions}.
	
	{label, Label}.
	{label, NodeRefs, Label}.
	
	{verbosity, VerbosityLevels}.
	{verbosity, NodeRefs, VerbosityLevels}.
	
	{stylesheet, CSSFile}.
	{stylesheet, NodeRefs, CSSFile}.
	
	{silent_connections, ConnTypes}.
	{silent_connections, NodeRefs, ConnTypes}.
	
	{multiply_timetraps, N}.
	{multiply_timetraps, NodeRefs, N}.
	
	{scale_timetraps, Bool}.
	{scale_timetraps, NodeRefs, Bool}.
	
	{cover, CoverSpecFile}.
	{cover, NodeRefs, CoverSpecFile}.
	
	{cover_stop, Bool}.
	{cover_stop, NodeRefs, Bool}.
	
	{include, IncludeDirs}.
	{include, NodeRefs, IncludeDirs}.
	
	{auto_compile, Bool},
	{auto_compile, NodeRefs, Bool},
	
	{config, ConfigFiles}.
	{config, ConfigDir, ConfigBaseNames}.
	{config, NodeRefs, ConfigFiles}.
	{config, NodeRefs, ConfigDir, ConfigBaseNames}.
	
	{userconfig, {CallbackModule, ConfigStrings}}.
	{userconfig, NodeRefs, {CallbackModule, ConfigStrings}}.
	
	{logdir, LogDir}.                                        
	{logdir, NodeRefs, LogDir}.
	
	{logopts, LogOpts}.
	{logopts, NodeRefs, LogOpts}.
	
	{create_priv_dir, PrivDirOption}.
	{create_priv_dir, NodeRefs, PrivDirOption}.
	
	{event_handler, EventHandlers}.
	{event_handler, NodeRefs, EventHandlers}.
	{event_handler, EventHandlers, InitArgs}.
	{event_handler, NodeRefs, EventHandlers, InitArgs}.
	
	{ct_hooks, CTHModules}.
	{ct_hooks, NodeRefs, CTHModules}.
	
	{enable_builtin_hooks, Bool}.
	
	{basic_html, Bool}.
	{basic_html, NodeRefs, Bool}.
	
        {release_shell, Bool}.

Test terms:

	{suites, Dir, Suites}.                                
	{suites, NodeRefs, Dir, Suites}.
	
	{groups, Dir, Suite, Groups}.
	{groups, NodeRefs, Dir, Suite, Groups}.
	
	{groups, Dir, Suite, Groups, {cases,Cases}}.
	{groups, NodeRefs, Dir, Suite, Groups, {cases,Cases}}.
	
	{cases, Dir, Suite, Cases}.                           
	{cases, NodeRefs, Dir, Suite, Cases}.
	
	{skip_suites, Dir, Suites, Comment}.
	{skip_suites, NodeRefs, Dir, Suites, Comment}.
	
	{skip_groups, Dir, Suite, GroupNames, Comment}.
	{skip_groups, NodeRefs, Dir, Suite, GroupNames, Comment}.
	
	{skip_cases, Dir, Suite, Cases, Comment}.
        {skip_cases, NodeRefs, Dir, Suite, Cases, Comment}.

Types:

	Bool            = true | false
	Constant        = atom()
	Value           = term()
	InclSpecsOption = join | separate
	TestSpecs       = string() | [string()]
	NodeAlias       = atom()
	Node            = node()
	NodeRef         = NodeAlias | Node | master
	NodeRefs        = all_nodes | [NodeRef] | NodeRef
	InitOptions     = term()
	Label           = atom() | string()
	VerbosityLevels = integer() | [{Category,integer()}]
	Category        = atom()
	CSSFile         = string()
	ConnTypes       = all | [atom()]
	N               = integer()
	CoverSpecFile   = string()
	IncludeDirs     = string() | [string()]
	ConfigFiles     = string() | [string()]
	ConfigDir       = string()
	ConfigBaseNames = string() | [string()]
	CallbackModule  = atom()
	ConfigStrings   = string() | [string()]
	LogDir          = string()
	LogOpts         = [term()]
	PrivDirOption   = auto_per_run | auto_per_tc | manual_per_tc
	EventHandlers   = atom() | [atom()]
	InitArgs        = [term()]
	CTHModules      = [CTHModule |
	                   {CTHModule, CTHInitArgs} |
	                   {CTHModule, CTHInitArgs, CTHPriority}]
	CTHModule       = atom()
	CTHInitArgs     = term()
	Dir             = string()
	Suites          = atom() | [atom()] | all
	Suite           = atom()
	Groups          = GroupPath | [GroupPath] | GroupSpec | [GroupSpec] | all
	GroupPath       = [GroupName]
	GroupSpec       = GroupName | {GroupName,Properties} | {GroupName,Properties,GroupSpec}
	GroupName       = atom()
	GroupNames      = GroupName | [GroupName]
	Cases           = atom() | [atom()] | all
        Comment         = string() | ""

	  {config, ["/home/testuser/tests/config/nodeA.cfg",
	            "/home/testuser/tests/config/nodeB.cfg"]}.
	  
	  {config, "/home/testuser/tests/config", ["nodeA.cfg","nodeB.cfg"]}.

	    %% 1a. no constant
	    {config, "/home/testuser/tests/config", ["nodeA.cfg","nodeB.cfg"]}.
	    {suites, "/home/testuser/tests/suites", all}.
	    
	    %% 1b. with constant
	    {define, 'TESTDIR', "/home/testuser/tests"}.
	    {config, "'TESTDIR'/config", ["nodeA.cfg","nodeB.cfg"]}.
	    {suites, "'TESTDIR'/suites", all}.
	    
	    %% 2a. no constants
	    {config, [testnode@host1, testnode@host2], "../config", ["nodeA.cfg","nodeB.cfg"]}.
	    {suites, [testnode@host1, testnode@host2], "../suites", [x_SUITE, y_SUITE]}.
	    
	    %% 2b. with constants
	    {define, 'NODE', testnode}.
	    {define, 'NODES', ['NODE'@host1, 'NODE'@host2]}.
	    {config, 'NODES', "../config", ["nodeA.cfg","nodeB.cfg"]}.
	    {suites, 'NODES', "../suites", [x_SUITE, y_SUITE]}.

	      %% using the old alias term
	      {config, "/home/testuser/tests/config/nodeA.cfg"}.
	      {alias, suite_dir, "/home/testuser/tests/suites"}.
	      {groups, suite_dir, x_SUITE, group1}.
	      
	      %% replacing with constants
	      {define, 'TestDir', "/home/testuser/tests"}.
	      {define, 'CfgDir', "'TestDir'/config"}.
	      {define, 'SuiteDir', "'TestDir'/suites"}.
	      {config, 'CfgDir', "nodeA.cfg"}.
	      {groups, 'SuiteDir', x_SUITE, group1}.

	    {define, 'Top', "/home/test"}.
	    {define, 'T1', "'Top'/t1"}.
	    {define, 'T2', "'Top'/t2"}.
	    {define, 'T3', "'Top'/t3"}.
	    {define, 'CfgFile', "config.cfg"}.
	    
	    {logdir, "'Top'/logs"}.
	    
	    {config, ["'T1'/'CfgFile'", "'T2'/'CfgFile'", "'T3'/'CfgFile'"]}.
	    
	    {suites, 'T1', all}.
	    {skip_suites, 'T1', [t1B_SUITE,t1D_SUITE], "Not implemented"}.
	    {skip_cases, 'T1', t1A_SUITE, [test3,test4], "Irrelevant"}.
	    {skip_cases, 'T1', t1C_SUITE, [test1], "Ignore"}.
	    
	    {suites, 'T2', [t2B_SUITE,t2C_SUITE]}.
	    {cases, 'T2', t2A_SUITE, [test4,test1,test7]}.
	    
	    {skip_suites, 'T3', all, "Not implemented"}.

The web based GUI, VTS, is started with the ct_run program. From the GUI you can load config files, and select directories, suites and cases to run. You can also state the config files, directories, suites and cases on the command line when starting the web based GUI.

From the GUI you can run tests and view the result and the logs.

Note that ct_run -vts will try to open the Common Test start page in an existing web browser window or start the browser if it is not running. Which browser should be started may be specified with the browser start command option:

]]>

Example:

Note that the browser must run as a separate OS process or VTS will hang!

If no specific browser start command is specified, Firefox will be the default browser on Unix platforms and Internet Explorer on Windows. If Common Test fails to start a browser automatically, or 'none' is specified as the value for -browser (i.e. -browser none), start your favourite browser manually and type in the URL that Common Test displays in the shell.

As the execution of the test suites proceed, events are logged in four different ways:

Typically the operator, who may run hundreds or thousands of test cases, doesn't want to fill the console with details about, or printouts from, the specific test cases. By default, the operator will only see:

If/when the operator wants to dig deeper into the general results, or the result of a specific test case, he should do so by following the links in the HTML presentation and take a look in the major or minor log files. The "all_runs.html" page is a practical starting point usually. It's located in logdir and contains a link to each test run including a quick overview (date and time, node name, number of tests, test names and test result totals).

An "index.html" page is written for each test run (i.e. stored in the "ct_run" directory tagged with node name, date and time). This file gives a short overview of all individual tests performed in the same test run. The test names follow this convention:

On the test run index page there is a link to the Common Test Framework Log file in which information about imported configuration data and general test progress is written. This log file is useful to get snapshot information about the test run during execution. It can also be very helpful when analyzing test results or debugging test suites.

On the test run index page it is noted if a test has missing suites (i.e. suites that Common Test has failed to compile). Names of the missing suites can be found in the Common Test Framework Log file.

The major log file shows a detailed report of the test run. It includes test suite and test case names, execution time, the exact reason for failures etc. The information is available in both a file with textual and with HTML representation. The HTML file shows a summary which gives a good overview of the test run. It also has links to each individual test case log file for quick viewing with an HTML browser.

The minor log files contain full details of every single test case, each one in a separate file. This way, it should be straightforward to compare the latest results to that of previous test runs, even if the set of test cases changes. If SASL is running, its logs will also be printed to the current minor log file by the cth_log_redirect built-in hook.

The full name of the minor log file (i.e. the name of the file including the absolute directory path) can be read during execution of the test case. It comes as value in the tuple {tc_logfile,LogFileName} in the Config list (which means it can also be read by a pre- or post Common Test hook function). Also, at the start of a test case, this data is sent with an event to any installed event handler. Please see the Event Handling chapter for details.

Which information goes where is user configurable via the test server controller. Three threshold values determine what comes out on screen, and in the major or minor log files. See the OTP Test Server manual for information. The contents that goes to the HTML log file is fixed however and cannot be altered.

The log files are written continously during a test run and links are always created initially when a test starts. This makes it possible to follow test progress simply by refreshing pages in the HTML browser. Statistics totals are not presented until a test is complete however.

Common Test uses an HTML Style Sheet (CSS file) to control the look of the HTML log files generated during test runs. If, for some reason, the log files are not displayed correctly in the browser of your choice, or you prefer a more primitive ("pre Common Test v1.6") look of the logs, use the start flag/option:

basic_html

This disables the use of Style Sheets, as well as JavaScripts (see table sorting above).

Common Test includes an optional feature to allow user HTML style sheets for customizing printouts. The functions in ct that print to a test case HTML log file (log/3 and pal/3) accept Category as first argument. With this argument it's possible to specify a category that can be mapped to a selector in a CSS definition. This is useful especially for coloring text differently depending on the type of (or reason for) the printout. Say you want one color for test system configuration information, a different one for test system state information and finally one for errors detected by the test case functions. The corresponding style sheet may look like this:

	  div.sys_config  { background:blue; color:white }
	  div.sys_state   { background:yellow; color:black }
	  div.error       { background:red; color:white }

To install the CSS file (Common Test inlines the definition in the HTML code), the name may be provided when executing ct_run. Example:

	  $ ct_run -dir $TEST/prog -stylesheet $TEST/styles/test_categories.css

Categories in a CSS file installed with the -stylesheet flag are on a global test level in the sense that they can be used in any suite which is part of the test run.

It is also possible to install style sheets on a per suite and per test case basis. Example:

	  -module(my_SUITE).
	  ...
	  suite() -> [..., {stylesheet,"suite_categories.css"}, ...].
	  ...
	  my_testcase(_) ->
	      ...
	      ct:log(sys_config, "Test node version: ~p", [VersionInfo]),
	      ...
	      ct:log(sys_state, "Connections: ~p", [ConnectionInfo]),
	      ...
	      ct:pal(error, "Error ~p detected! Info: ~p", [SomeFault,ErrorInfo]),
	      ct:fail(SomeFault).

If the style sheet is installed as in this example, the categories are private to the suite in question. They can be used by all test cases in the suite, but can not be used by other suites. A suite private style sheet, if specified, will be used in favour of a global style sheet (one specified with the -stylesheet flag). A stylesheet tuple (as returned by suite/0 above) can also be returned from a test case info function. In this case the categories specified in the style sheet can only be used in that particular test case. A test case private style sheet is used in favour of a suite or global level style sheet.

In a tuple {stylesheet,CSSFile}, if CSSFile is specified with a path, e.g. "$TEST/styles/categories.css", this full name will be used to locate the file. If only the file name is specified however, e.g. "categories.css", then the CSS file is assumed to be located in the data directory, data_dir, of the suite. The latter usage is recommended since it is portable compared to hard coding path names in the suite!

The Category argument in the example above may have the value (atom) sys_config (white on blue), sys_state (black on yellow) or error (white on red).

You can order Common Test to repeat the tests you specify. You can choose to repeat tests a certain number of times, repeat tests for a specific period of time, or repeat tests until a particular stop time is reached. If repetition is controlled by means of time, it is also possible to specify what action Common Test should take upon timeout. Either Common Test performs all tests in the current run before stopping, or it stops as soon as the current test job is finished. Repetition can be activated by means of ct_run start flags, or tuples in the ct:run:test/1 option list argument. The flags (options in parenthesis) are:

The duration time, DurTime, is specified as HHMMSS. Example: -duration 012030 or {duration,"012030"}, means the tests will be executed and (if time allows) repeated, until timeout occurs after 1 h, 20 min and 30 secs. StopTime can be specified as HHMMSS and is then interpreted as a time today (or possibly tomorrow). StopTime can also be specified as YYMoMoDDHHMMSS. Example: -until 071001120000 or {until,"071001120000"}, which means the tests will be executed and (if time allows) repeated, until 12 o'clock on the 1st of Oct 2007.

When timeout occurs, Common Test will never abort the ongoing test case, since this might leave the system under test in an undefined, and possibly bad, state. Instead Common Test will by default finish the current test run before stopping. If the force_stop flag is given, Common Test will stop as soon as the current test job is finished, and if the force_stop flag is given with skip_rest Common Test will only complete the current test case and skip the rest of the tests in the test job. Note that since Common Test always finishes off at least the current test case, the time specified with duration or until is never definitive!

Log files from every single repeated test run is saved in normal Common Test fashion (see above). Common Test may later support an optional feature to only store the last (and possibly the first) set of logs of repeated test runs, but for now the user must be careful not to run out of disk space if tests are repeated during long periods of time.

Note that for each test run that is part of a repeated session, information about the particular test run is printed in the Common Test Framework Log. There you can read the repetition number, remaining time, etc.

Example 1:

          $ ct_run -dir $TEST_ROOT/to1 $TEST_ROOT/to2 -duration 001000 -force_stop

Here the suites in test directory to1, followed by the suites in to2, will be executed in one test run. A timeout event will occur after 10 minutes. As long as there is time left, Common Test will repeat the test run (i.e. starting over with the to1 test). When the timeout occurs, Common Test will stop as soon as the current job is finished (because of the force_stop flag). As a result, the specified test run might be aborted after the to1 test and before the to2 test.

Example 2:

          $ ct_run -dir $TEST_ROOT/to1 $TEST_ROOT/to2 -duration 001000 -forces_stop skip_rest

Here the same test run as in Example 1, but with the force_stop flag set to skip_rest. If the timeout occurs while executing tests in directory to1, the rest of the test cases in to1 will be skipped and then the test will be aborted without running the tests in to2 another time. If the timeout occurs while executing tests in directory to2, then the rest of the test cases in to2 will be skipped and then the test will be aborted.

Example 3:

          $ date
	  Fri Sep 28 15:00:00 MEST 2007

          $ ct_run -dir $TEST_ROOT/to1 $TEST_ROOT/to2 -until 160000

Here the same test run as in the example above will be executed (and possibly repeated). In this example, however, the timeout will occur after 1 hour and when that happens, Common Test will finish the entire test run before stopping (i.e. the to1 and to2 test will always both be executed in the same test run).

Example 4:

          $ ct_run -dir $TEST_ROOT/to1 $TEST_ROOT/to2 -repeat 5

Here the test run, including both the to1 and the to2 test, will be repeated 5 times.

The protocol handling processes in Common Test, implemented by ct_telnet, ct_ssh, ct_ftp etc, do verbose printing to the test case logs. This can be switched off by means of the -silent_connections flag:

	ct_run -silent_connections [conn_types]
      

where conn_types specifies ssh, telnet, ftp, rpc and/or snmp.

Example:

	ct_run ... -silent_connections ssh telnet

switches off logging for ssh and telnet connections.

	ct_run ... -silent_connections

switches off logging for all connection types.

Fatal communication error and reconnection attempts will always be printed even if logging has been suppressed for the connection type in question. However, operations such as sending and receiving data will be performed silently.

It is possible to also specify silent_connections in a test suite. This is accomplished by returning a tuple, {silent_connections,ConnTypes}, in the suite/0 or test case info list. If ConnTypes is a list of atoms (ssh, telnet, ftp, rpc and/or snmp), output for any corresponding connections will be suppressed. Full logging is per default enabled for any connection of type not specified in ConnTypes. Hence, if ConnTypes is the empty list, logging is enabled for all connections.

Example:

	
	-module(my_SUITE).

	suite() -> [..., {silent_connections,[telnet,ssh]}, ...].

	...

	my_testcase1() ->
	    [{silent_connections,[ssh]}].

	my_testcase1(_) ->
	    ...

	my_testcase2(_) ->
	    ...
      

In this example, suite/0 tells Common Test to suppress printouts from telnet and ssh connections. This is valid for all test cases. However, my_testcase1/0 specifies that for this test case, only ssh should be silent. The result is that my_testcase1 will get telnet info (if any) printed in the log, but not ssh info. my_testcase2 will get no info from either connection printed.

silent_connections may also be specified with a term in a test specification (see Test Specifications). Connections provided with the silent_connections start flag/option, will be merged with any connections listed in the test specification.

The silent_connections start flag/option and test specification term, overrides any settings made by the info functions inside the test suite.