Keyvals
Job keyvals are key/value pairs, used to cache/exchange data about jobs between different services in autotest, via the database. There are two keyvals tables, afe_job_keyvals and tko_job_keyvals. Both tables have a job_id column for keyvals to be foreign keyed to a job. The job_id can be a suite job id if jobs are queued by a suite run, or test job id if the job is queued directly from atest/run_remote_test/autoserv.
The initial job keyvals get specified as part of the arguments to the create_job RPC and entered into the database (into the afe_job_keyvals table). Then, before we go to run a job, we pull the keyvals out of the database and write them to a file. This is done by a class named TaskWithJobKeyvals that is a mixin that gets included for the Agents representing job runs. The parsing of these keyvals back into the database happens when the scheduler kicks off tko/parse.py to parse job results during the PARSING phase. tko/parse.py calls tko/db.py:insert_job(), which contains the call to update_job_keyvals() which does the actual job keyval writing. These get inserted into tko_job_keyvals, so the initial keyvals are always in afe_job_keyvals, and the final results in tko_job_keyvals.
afe_job_keyvals stores the a job's suite and build information.
tko_job_keyvals stores the test result information, including:
user that requested the job
job start/end time (job_started, job_queued, job_finished)
perf keyvals, which are up to individual tests to create as they see fit. The use and lifecycle of perf keyvals is explained in detail on a separate webpage.
Importantly, the tko_job_keyvals entry for a suite job stores a dictionary between hashed test names and job_id-owner. After a suite job is finished, run_suite uses this dictionary to find out the job url for a particular test. The reason for this is that when a suite is started, all keyvals are keyed by suite job id. The test job id is set only after the test job is started. After a test job has finished, autoserv creates logs a keyval (for the test’s job id) with the hashed test name as the key and job_id-owner as the value. run_suite pulls the keyval from tko_job_keyval table and maps the test job to its result page, which is the test job page, rather than suite job page.