aboutsummaryrefslogtreecommitdiffstats
path: root/docs/content/introduction/design.md
blob: ba31477c4dc09841accac55420d72302cfcc687b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
---
title: "Design"
weight: 3
---

# Design

FD.io CSIT system design needs to meet continuously expanding requirements of
FD.io projects including VPP, related sub-systems (e.g. plugin applications,
DPDK drivers) and FD.io applications (e.g. DPDK applications), as well as
growing number of compute platforms running those applications. With CSIT
project scope and charter including both FD.io continuous testing AND
performance trending/comparisons, those evolving requirements further amplify
the need for CSIT framework modularity, flexibility and usability.

## Design Hierarchy

CSIT follows a hierarchical system design with SUTs and DUTs at the bottom level
of the hierarchy, presentation level at the top level and a number of functional
layers in-between. The current CSIT system design including CSIT framework is
depicted in the figure below.

{{< figure src="/cdocs/csit_design_picture.svg" title="CSIT Design" >}}

A brief bottom-up description is provided here:

1. SUTs, DUTs, TGs
   - SUTs - Systems Under Test;
   - DUTs - Devices Under Test;
   - TGs - Traffic Generators;
2. Level-1 libraries - Robot and Python
   - Lowest level CSIT libraries abstracting underlying test environment, SUT,
     DUT and TG specifics;
   - Used commonly across multiple L2 KWs;
   - Performance and functional tests:
     - L1 KWs (KeyWords) are implemented as RF libraries and Python
       libraries;
   - Performance TG L1 KWs:
     - All L1 KWs are implemented as Python libraries:
       - Support for TRex only today;
       - CSIT IXIA drivers in progress;
   - Performance data plane traffic profiles:
     - TG-specific stream profiles provide full control of:
       - Packet definition - layers, MACs, IPs, ports, combinations thereof
         e.g. IPs and UDP ports;
       - Stream definitions - different streams can run together, delayed,
         one after each other;
       - Stream profiles are independent of CSIT framework and can be used
         in any T-rex setup, can be sent anywhere to repeat tests with
         exactly the same setup;
       - Easily extensible - one can create a new stream profile that meets
         tests requirements;
       - Same stream profile can be used for different tests with the same
         traffic needs;
   - Functional data plane traffic scripts:
     - Scapy specific traffic scripts;
3. Level-2 libraries - Robot resource files:
   - Higher level CSIT libraries abstracting required functions for executing
     tests;
   - L2 KWs are classified into the following functional categories:
     - Configuration, test, verification, state report;
     - Suite setup, suite teardown;
     - Test setup, test teardown;
4. Tests - Robot:
   - Test suites with test cases;
   - Performance tests using physical testbed environment:
     - VPP;
     - DPDK-Testpmd;
     - DPDK-L3Fwd;
   - Tools:
     - Documentation generator;
     - Report generator;
     - Testbed environment setup ansible playbooks;
     - Operational debugging scripts;

5. Test Lifecycle Abstraction

A well coded test must follow a disciplined abstraction of the test
lifecycles that includes setup, configuration, test and verification. In
addition to improve test execution efficiency, the commmon aspects of
test setup and configuration shared across multiple test cases should be
done only once. Translating these high-level guidelines into the Robot
Framework one arrives to definition of a well coded RF tests for FD.io
CSIT. Anatomy of Good Tests for CSIT:

1. Suite Setup - Suite startup Configuration common to all Test Cases in suite:
   uses Configuration KWs, Verification KWs, StateReport KWs;
2. Test Setup - Test startup Configuration common to multiple Test Cases: uses
   Configuration KWs, StateReport KWs;
3. Test Case - uses L2 KWs with RF Gherkin style:
   - prefixed with {Given} - Verification of Test setup, reading state: uses
     Configuration KWs, Verification KWs, StateReport KWs;
   - prefixed with {When} - Test execution: Configuration KWs, Test KWs;
   - prefixed with {Then} - Verification of Test execution, reading state: uses
     Verification KWs, StateReport KWs;
4. Test Teardown - post Test teardown with Configuration cleanup and
   Verification common to multiple Test Cases - uses: Configuration KWs,
   Verification KWs, StateReport KWs;
5. Suite Teardown - Suite post-test Configuration cleanup: uses Configuration
   KWs, Verification KWs, StateReport KWs;

## RF Keywords Functional Classification

CSIT RF KWs are classified into the functional categories matching the test
lifecycle events described earlier. All CSIT RF L2 and L1 KWs have been grouped
into the following functional categories:

1. Configuration;
2. Test;
3. Verification;
4. StateReport;
5. SuiteSetup;
6. TestSetup;
7. SuiteTeardown;
8. TestTeardown;

## RF Keywords Naming Guidelines

Readability counts: "..code is read much more often than it is written."
Hence following a good and consistent grammar practice is important when
writing Robot Framework KeyWords and Tests. All CSIT test cases
are coded using Gherkin style and include only L2 KWs references. L2 KWs are
coded using simple style and include L2 KWs, L1 KWs, and L1 python references.
To improve readability, the proposal is to use the same grammar for both
Robot Framework KW styles, and to formalize the grammar of English
sentences used for naming the Robot Framework KWs. Robot
Framework KWs names are short sentences expressing functional description of
the command. They must follow English sentence grammar in one of the following
forms:

1. **Imperative** - verb-object(s): *"Do something"*, verb in base form.
2. **Declarative** - subject-verb-object(s): *"Subject does something"*, verb in
   a third-person singular present tense form.
3. **Affirmative** - modal_verb-verb-object(s): *"Subject should be something"*,
   *"Object should exist"*, verb in base form.
4. **Negative** - modal_verb-Not-verb-object(s): *"Subject should not be
   something"*, *"Object should not exist"*, verb in base form.

Passive form MUST NOT be used. However a usage of past participle as an
adjective is okay. See usage examples provided in the Coding guidelines
section below. Following sections list applicability of the above
grammar forms to different Robot Framework KW categories. Usage
examples are provided, both good and bad.

## Coding Guidelines

Coding guidelines can be found on
[Design optimizations wiki page](https://wiki.fd.io/view/CSIT/Design_Optimizations).