Caching mechanism for Robot Framework tests. Works within a single test run and across multiple test
runs. Works with Pabot, though it requires --pabotlib
.
In one word: Performance.
When testing, we sometimes want to reuse work we did in a different test. Examples of this include API gateway sessions, user sessions, and expensive calculations. If we can reuse this work, we don't need to spend time redoing it every test.
Sometimes we even want to reuse the work we did in a previous test run. This allows us to speed up our workflow when writing tests.
CacheLibrary solves these problems by providing a caching mechanism that's stored both in memory and in a file.
CacheLibrary works with Pabot.
- Pabot @ <=1 is not supported
- Pabot @ >=2 and <4 requires the
--pabotlib
command line argument. - Pabot @ >=4 won't work with the
--no-pabotlib
command line argument.
Supporting Pabot is achieved by a combination of locks and parallel variables. This makes CacheLibrary stable when run in parallel without losing stored values.
All CacheLibrary tests are run with Pabot to ensure that the above statements are true.
-
Install CacheLibrary with pip. Run the following command:
pip install robotframework-cache
-
Import it from your
.robot
or.resource
file. Add the following line to theSettings
section:Library CacheLibrary
-
Add the cache file to
.gitignore
. If you use the default file path, add the following to your.gitignore
:robotframework-cache.json
Store a value, and retrieve it later
Cache Store Value foo Hello, world
# Do something interesting
${value} = Cache Retrieve Value foo
Should Be Equal ${value} Hello, world
The keyword below fetches or reuses a session token.
Everwhere you need the session token, you can use this keyword. CacheLibrary will ensure that you're only requesting a new session token once. After which it will reuse the session token.
CacheLibrary will even do this across test runs. This way, you don't have to request the session token every time you run a test. This can be a great help while making or debugging a test.
Get Api Session Token
${cache_key} = Set Variable api-session
${cached_token} = Cache Retrieve value ${cache_key}
IF $cached_token is not $None
RETURN ${cached_token}
END
# Request a new session token
Cache Store Value ${cache_key} ${new_token}
RETURN ${new_token}
Alternatively, you can use the convenience keyword Run Keyword And Cache Output
to do the same
thing:
Get Api Session Token
${token} = Run Keyword And Cache Output Get Api Session Token Uncached
RETURN ${token}
Get Api Session Token Uncached
[Tags] robot:private
# Request a new session token
RETURN ${new_token}
When storing a value in the cache, you also define how long it should remain valid.
Cache Store Value key=amazing value=beautiful expire_in_seconds=10
The value beautiful
will expire 10 seconds from the moment it's stored.
If you try to retrieve an expired value with Cache Retrieve Value
it will return None
like it
would if it was never stored.
The default retention is 3600 seconds (1 hour).
When importing the library, you can provide an alternative cache file path.
Library CacheLibrary file_path=alternative-cache-file.json
A big cache file can indicate an issue with CacheLibary or with how it's used. To help you spot these issues, CacheLibrary will warn you if the cache file is very big. By default it will warn if the file is larger than 500Kb.
You can change this threshold when importing the library. For example, changing it to 1Mb:
Library CacheLibrary file_size_warning_bytes=1000000
If you need to reset the cache for any reason, simply remove or empty the cache file
(default: robotframework-cache.json
).
Alternatively, you can use the keyword Cache Reset
for the same purpose.
Contributions are always welcome :)
-
Install the dependencies with
poetry
.poetry install --with test
-
Run the following commands in the repository root.
robot test/integration robot test/acceptance/run.robot pabot --pabotlib test/integration pabot --pabotlib test/acceptance/run.robot pabot --testlevelsplit --pabotlib test/integration pabot --testlevelsplit --pabotlib test/acceptance/run.robot