1tdc - Adding plugins for tdc 2 3Author: Brenda J. Butler - bjb@mojatatu.com 4 5ADDING PLUGINS 6-------------- 7 8A new plugin should be written in python as a class that inherits from TdcPlugin. 9There are some examples in plugin-lib. 10 11The plugin can be used to add functionality to the test framework, 12such as: 13 14- adding commands to be run before and/or after the test suite 15- adding commands to be run before and/or after the test cases 16- adding commands to be run before and/or after the execute phase of the test cases 17- ability to alter the command to be run in any phase: 18 pre (the pre-suite stage) 19 prepare 20 execute 21 verify 22 teardown 23 post (the post-suite stage) 24- ability to add to the command line args, and use them at run time 25 26 27The functions in the class should follow the following interfaces: 28 29 def __init__(self) 30 def pre_suite(self, testcount, testidlist) # see "PRE_SUITE" below 31 def post_suite(self, ordinal) # see "SKIPPING" below 32 def pre_case(self, test_ordinal, testid) # see "PRE_CASE" below 33 def post_case(self) 34 def pre_execute(self) 35 def post_execute(self) 36 def adjust_command(self, stage, command) # see "ADJUST" below 37 def add_args(self, parser) # see "ADD_ARGS" below 38 def check_args(self, args, remaining) # see "CHECK_ARGS" below 39 40 41PRE_SUITE 42 43This method takes a testcount (number of tests to be run) and 44testidlist (array of test ids for tests that will be run). This is 45useful for various things, including when an exception occurs and the 46rest of the tests must be skipped. The info is stored in the object, 47and the post_suite method can refer to it when dumping the "skipped" 48TAP output. The tdc.py script will do that for the test suite as 49defined in the test case, but if the plugin is being used to run extra 50tests on each test (eg, check for memory leaks on associated 51co-processes) then that other tap output can be generated in the 52post-suite method using this info passed in to the pre_suite method. 53 54 55SKIPPING 56 57The post_suite method will receive the ordinal number of the last 58test to be attempted. It can use this info when outputting 59the TAP output for the extra test cases. 60 61 62PRE_CASE 63 64The pre_case method will receive the ordinal number of the test 65and the test id. Useful for outputing the extra test results. 66 67 68ADJUST 69 70The adjust_command method receives a string representing 71the execution stage and a string which is the actual command to be 72executed. The plugin can adjust the command, based on the stage of 73execution. 74 75The stages are represented by the following strings: 76 77 'pre' 78 'setup' 79 'command' 80 'verify' 81 'teardown' 82 'post' 83 84The adjust_command method must return the adjusted command so tdc 85can use it. 86 87 88ADD_ARGS 89 90The add_args method receives the argparser object and can add 91arguments to it. Care should be taken that the new arguments do not 92conflict with any from tdc.py or from other plugins that will be used 93concurrently. 94 95The add_args method should return the argparser object. 96 97 98CHECK_ARGS 99 100The check_args method is so that the plugin can do validation on 101the args, if needed. If there is a problem, and Exception should 102be raised, with a string that explains the problem. 103 104eg: raise Exception('plugin xxx, arg -y is wrong, fix it') 105