xref: /openbmc/openbmc-test-automation/docs/redfish_coding_guidelines.md (revision 5731818de0ce446ceaafc7e75ae39da1b69942ae) 
1# Redfish Coding Guidelines
2
3- For robot programs wishing to run Redfish commands, include the following in
4  your robot file:
5
6  ```
7  *** Settings ***
8
9  Resource                    bmc_redfish_resource.robot
10  ```
11
12- This git repository has some redfish wrapper modules:
13
14  - [redfish_plus.py](../lib/redfish_plus.py)
15  - [bmc_redfish.py](../lib/bmc_redfish.py)
16  - [bmc_redfish_utils.py](../lib/bmc_redfish_utils.py)
17  - Redfish wrapper module features:
18
19    For all Redfish REST requests (get, head, post, put, patch, delete):
20
21    - Support for python-like strings for all arguments which allows callers to
22      easily specify complex arguments such as lists or dictionaries.
23
24      So instead of coding this:
25
26      ```
27          ${ldap_type_dict}=  Create Dictionary  ServiceEnabled=${False}
28          ${body}=  Create Dictionary  ${LDAP_TYPE}=${ldap_type_dict}
29          Redfish.Patch  ${REDFISH_BASE_URI}AccountService  body=${body}
30      ```
31
32      You can do it in one fell swoop like this:
33
34      ```
35          Redfish.Patch  ${REDFISH_BASE_URI}AccountService  body={'${LDAP_TYPE}': {'ServiceEnabled': ${False}}}
36      ```
37
38    - Support for **valid_status_codes** argument and auto-failure:
39
40      As mentioned above, this argument may be either an actual robot/python
41      list or it may be a string value which python can translate into a list.
42
43      The default value is [${HTTP_OK}].
44
45      This means that the Redfish REST request will fail **automatically** if
46      the resulting status code is not found in the valid_status_codes list.
47
48      So instead of having to do this:
49
50      ```
51          ${resp}=  Redfish.Get  ${EVENT_LOG_URI}Entries
52          Should Be Equal As Strings  ${resp.status_code}  ${HTTP_OK}
53      ```
54
55      You can simply do this:
56
57      ```
58          ${resp}=  Redfish.Get  ${EVENT_LOG_URI}Entries
59      ```
60
61      If, for some reason, you **expect** your command to fail, you can specify
62      the expected status code or codes:
63
64      ```
65      Redfish.Patch  ${REDFISH_BASE_URI}UpdateService  body={'ApplyTime' : 'Invalid'}  valid_status_codes=[${HTTP_BAD_REQUEST}]
66      ```
67
68  - Login defaults for path, username and password are https://${OPENBMC_HOST},
69    ${OPENBMC_USERNAME}, ${OPENBMC_PASSWORD}.
70  - Many utility functions are available. Examples:;
71
72    - get_properties
73    - get_attributes
74    - get_session_info
75    - list_request
76    - enumerate_request
77
78# Rules for use of Redfish.Login and Redfish.Logout
79
80It is desirable to avoid excessive redfish logins/logouts for the following
81reasons:
82
83- It simplifies the code base.
84- It allows calling keywords and testcases to keep control over login parameters
85  like USERNAME, PASSWORD, etc. Consider the following example:
86
87  ```
88  # Login to redfish with non-standard username/password.
89  Redfish.Login  ${LDAP_USER}  ${LDAP_USER_PASSWORD}
90  # Run 'Some Keyword' while logged in as ${LDAP_USER}/${LDAP_USER_PASSWORD}.
91  Some Keyword
92  ```
93
94  If 'Some Keyword' in the example above does its own Redfish.Login, it will
95  thwart the stated purpose of the caller.
96
97**Rules:**
98
99- Login should be done once in Suite Setup:
100
101  ```
102  *** Keywords ***
103  Suite Setup Execution
104      Redfish.Login
105  ```
106
107- Logout should be done once in Suite Teardown:
108  ```
109  *** Keywords ***
110  Suite Teardown Execution
111      Redfish.Logout
112  ```
113- As a result of the first two rules, all keywords and testcases that call upon
114  redfish functions (e.g. Redfish.Get, Redfish.Patch, etc.) have a right to
115  expect that login/logout have already been handled. Therefore, such keywords
116  and testcases should NOT do logins and logouts themselves.
117- There may be exceptions to the above but they require justification (e.g. a
118  test whose purpose is to verify that it can login with an **alternate**
119  username, etc.).
120- Any keyword or test case which breaks the above rules is responsible for
121  setting things right (i.e. back to a logged in state).
122
123# Rules for use of data/variables.py
124
125Avoid defining variables in data/variables.py for Redfish URIs.
126
127There's no obvious benefit to using such variables. Conversely, with literal
128values, it is much easier for the programmer to interpret the code.
129
130Consider the following example.
131
132Here's an excerpt from data/variables.py:
133
134```
135# Redfish variables.
136REDFISH_BASE_URI = '/redfish/v1/'
137...
138REDFISH_ACCOUNTS = 'AccountService/Accounts/'
139REDFISH_ACCOUNTS_URI = REDFISH_BASE_URI + REDFISH_ACCOUNTS
140```
141
142And here is a corresponding Robot code example:
143
144```
145    # Rather than coding this:
146    Redfish.Delete  ${REDFISH_ACCOUNTS_URI}user_user
147
148    # Code this:
149    Redfish.Delete  /redfish/v1/AccountService/Accounts/user_user
150```
151