1YAMLLINT(1) yamllint YAMLLINT(1)
2
6 yamllint -
7 A linter for YAML files.
9 yamllint does not only check for syntax validity, but for weirdnesses
11 like key repetition and cosmetic problems such as lines length, trail‐
12 ing spaces, indentation, etc.
13
15 [image: yamllint screenshot] [image]
16 NOTE:
18 The default output format is inspired by eslint, a great linting
19 tool for Javascript.
20
22 Quickstart
23 Installing yamllint
24 On Fedora / CentOS:
25 sudo dnf install yamllint
27 On Debian 8+ / Ubuntu 16.04+:
29 sudo apt-get install yamllint
31 On Mac OS 10.11+:
33 brew install yamllint
35 Alternatively using pip, the Python package manager:
37 pip install --user yamllint
39 If you prefer installing from source, you can run, from the source
41 directory:
42 python setup.py sdist
44 pip install --user dist/yamllint-*.tar.gz
45 Running yamllint
47 Basic usage:
48 yamllint file.yml other-file.yaml
50 You can also lint all YAML files in a whole directory:
52 yamllint .
54 Or lint a YAML stream from standard input:
56 echo -e 'this: is\nvalid: YAML' | yamllint -
58 The output will look like (colors are not displayed here):
60 file.yml
62 1:4 error trailing spaces (trailing-spaces)
63 4:4 error wrong indentation: expected 4 but found 3 (indentation)
64 5:4 error duplication of key "id-00042" in mapping (key-duplicates)
65 6:6 warning comment not indented like content (comments-indentation)
66 12:6 error too many spaces after hyphen (hyphens)
67 15:12 error too many spaces before comma (commas)
68 other-file.yaml
70 1:1 warning missing document start "---" (document-start)
71 6:81 error line too long (87 > 80 characters) (line-length)
72 10:1 error too many blank lines (4 > 2) (empty-lines)
73 11:4 error too many spaces inside braces (braces)
74 By default, the output of yamllint is colored when run from a terminal,
76 and pure text in other cases. Add the -f standard arguments to force
77 non-colored output. Use the -f colored arguments to force colored out‐
78 put.
79 Add the -f parsable arguments if you need an output format parsable by
81 a machine (for instance for syntax highlighting in text editors). The
82 output will then look like:
83 file.yml:6:2: [warning] missing starting space in comment (comments)
85 file.yml:57:1: [error] trailing spaces (trailing-spaces)
86 file.yml:60:3: [error] wrong indentation: expected 4 but found 2 (indentation)
87 If you have a custom linting configuration file (see how to configure
89 yamllint), it can be passed to yamllint using the -c option:
90 yamllint -c ~/myconfig file.yaml
92 NOTE:
94 If you have a .yamllint file in your working directory, it will be
95 automatically loaded as configuration by yamllint.
96 Configuration
98 yamllint uses a set of rules to check source files for problems. Each
99 rule is independent from the others, and can be enabled, disabled or
100 tweaked. All these settings can be gathered in a configuration file.
101 To use a custom configuration file, use the -c option:
103 yamllint -c /path/to/myconfig file-to-lint.yaml
105 If -c is not provided, yamllint will look for a configuration file in
107 the following locations (by order of preference):
108 · .yamllint in the current working directory
110 · $XDG_CONFIG_HOME/yamllint/config
112 · ~/.config/yamllint/config
114 Finally if no config file is found, the default configuration is
116 applied.
117 Default configuration
119 Unless told otherwise, yamllint uses its default configuration:
120 ---
122 rules:
124 braces: enable
125 brackets: enable
126 colons: enable
127 commas: enable
128 comments:
129 level: warning
130 comments-indentation:
131 level: warning
132 document-end: disable
133 document-start:
134 level: warning
135 empty-lines: enable
136 empty-values: enable
137 hyphens: enable
138 indentation: enable
139 key-duplicates: enable
140 key-ordering: disable
141 line-length: enable
142 new-line-at-end-of-file: enable
143 new-lines: enable
144 octal-values: enable
145 quoted-strings: disable
146 trailing-spaces: enable
147 truthy:
148 level: warning
149 Details on rules can be found on the rules page.
152 There is another pre-defined configuration named relaxed. As its name
154 suggests, it is more tolerant:
155 ---
157 extends: default
159 rules:
161 braces:
162 level: warning
163 max-spaces-inside: 1
164 brackets:
165 level: warning
166 max-spaces-inside: 1
167 colons:
168 level: warning
169 commas:
170 level: warning
171 comments: disable
172 comments-indentation: disable
173 document-start: disable
174 empty-lines:
175 level: warning
176 hyphens:
177 level: warning
178 indentation:
179 level: warning
180 indent-sequences: consistent
181 line-length:
182 level: warning
183 allow-non-breakable-inline-mappings: true
184 truthy: disable
185 It can be chosen using:
188 yamllint -d relaxed file.yml
190 Extending the default configuration
192 When writing a custom configuration file, you don't need to redefine
193 every rule. Just extend the default configuration (or any
194 already-existing configuration file).
195 For instance, if you just want to disable the comments-indentation
197 rule, your file could look like this:
198 # This is my first, very own configuration file for yamllint!
200 # It extends the default conf by adjusting some options.
201 extends: default
203 rules:
205 comments-indentation: disable # don't bother me with this rule
206 Similarly, if you want to set the line-length rule as a warning and be
208 less strict on block sequences indentation:
209 extends: default
211 rules:
213 # 80 chars should be enough, but don't fail if a line is longer
214 line-length:
215 max: 80
216 level: warning
217 # accept both key:
219 # - item
220 #
221 # and key:
222 # - item
223 indentation:
224 indent-sequences: whatever
225 Custom configuration without a config file
227 It is possible -- although not recommended -- to pass custom configura‐
228 tion options to yamllint with the -d (short for --config-data) option.
229 Its content can either be the name of a pre-defined conf (example:
231 default or relaxed) or a serialized YAML object describing the configu‐
232 ration.
233 For instance:
235 yamllint -d "{extends: relaxed, rules: {line-length: {max: 120}}}" file.yaml
237 Errors and warnings
239 Problems detected by yamllint can be raised either as errors or as
240 warnings. The CLI will output them (with different colors when using
241 the colored output format, or auto when run from a terminal).
242 By default the script will exit with a return code 1 only when there is
244 one or more error(s).
245 However if strict mode is enabled with the -s (or --strict) option, the
247 return code will be:
248 · 0 if no errors or warnings occur
250 · 1 if one or more errors occur
252 · 2 if no errors occur, but one or more warnings occur
254 Ignoring paths
256 It is possible to exclude specific files or directories, so that the
257 linter doesn't process them.
258 You can either totally ignore files (they won't be looked at):
260 extends: default
262 ignore: |
264 /this/specific/file.yaml
265 all/this/directory/
266 *.template.yaml
267 or ignore paths only for specific rules:
269 extends: default
271 rules:
273 trailing-spaces:
274 ignore: |
275 /this-file-has-trailing-spaces-but-it-is-OK.yaml
276 /generated/*.yaml
277 Note that this .gitignore-style path pattern allows complex path exclu‐
279 sion/inclusion, see the pathspec README file for more details. Here is
280 a more complex example:
281 # For all rules
283 ignore: |
284 *.dont-lint-me.yaml
285 /bin/
286 !/bin/*.lint-me-anyway.yaml
287 extends: default
289 rules:
291 key-duplicates:
292 ignore: |
293 generated
294 *.template.yaml
295 trailing-spaces:
296 ignore: |
297 *.ignore-trailing-spaces.yaml
298 ascii-art/*
299 Rules
301 When linting a document with yamllint, a series of rules (such as
302 line-length, trailing-spaces, etc.) are checked against.
303 A configuration file can be used to enable or disable these rules, to
305 set their level (error or warning), but also to tweak their options.
306 This page describes the rules and their options.
308 List of rules
310 · braces
311 · brackets
313 · colons
315 · commas
317 · comments
319 · comments-indentation
321 · document-end
323 · document-start
325 · empty-lines
327 · empty-values
329 · hyphens
331 · indentation
333 · key-duplicates
335 · key-ordering
337 · line-length
339 · new-line-at-end-of-file
341 · new-lines
343 · octal-values
345 · quoted-strings
347 · trailing-spaces
349 · truthy
351 braces
353 Use this rule to control the number of spaces inside braces ({ and }).
354 Options.INDENT 0.0
355 · min-spaces-inside defines the minimal number of spaces required
357 inside braces.
358 · max-spaces-inside defines the maximal number of spaces allowed inside
360 braces.
361 · min-spaces-inside-empty defines the minimal number of spaces required
363 inside empty braces.
364 · max-spaces-inside-empty defines the maximal number of spaces allowed
366 inside empty braces.
367Examples.INDENT 0.0
368 1. With braces: {min-spaces-inside: 0, max-spaces-inside: 0}
370 the following code snippet would PASS:
372 object: {key1: 4, key2: 8}
374 the following code snippet would FAIL:
376 object: { key1: 4, key2: 8 }
378 2. With braces: {min-spaces-inside: 1, max-spaces-inside: 3}
380 the following code snippet would PASS:
382 object: { key1: 4, key2: 8 }
384 the following code snippet would PASS:
386 object: { key1: 4, key2: 8 }
388 the following code snippet would FAIL:
390 object: { key1: 4, key2: 8 }
392 the following code snippet would FAIL:
394 object: {key1: 4, key2: 8 }
396 3. With braces: {min-spaces-inside-empty: 0, max-spaces-inside-empty:
398 0}
399 the following code snippet would PASS:
401 object: {}
403 the following code snippet would FAIL:
405 object: { }
407 4. With braces: {min-spaces-inside-empty: 1, max-spaces-inside-empty:
409 -1}
410 the following code snippet would PASS:
412 object: { }
414 the following code snippet would FAIL:
416 object: {}
418 brackets
420 Use this rule to control the number of spaces inside brackets ([ and
421 ]). Options.INDENT 0.0
422 · min-spaces-inside defines the minimal number of spaces required
424 inside brackets.
425 · max-spaces-inside defines the maximal number of spaces allowed inside
427 brackets.
428 · min-spaces-inside-empty defines the minimal number of spaces required
430 inside empty brackets.
431 · max-spaces-inside-empty defines the maximal number of spaces allowed
433 inside empty brackets.
434Examples.INDENT 0.0
435 1. With brackets: {min-spaces-inside: 0, max-spaces-inside: 0}
437 the following code snippet would PASS:
439 object: [1, 2, abc]
441 the following code snippet would FAIL:
443 object: [ 1, 2, abc ]
445 2. With brackets: {min-spaces-inside: 1, max-spaces-inside: 3}
447 the following code snippet would PASS:
449 object: [ 1, 2, abc ]
451 the following code snippet would PASS:
453 object: [ 1, 2, abc ]
455 the following code snippet would FAIL:
457 object: [ 1, 2, abc ]
459 the following code snippet would FAIL:
461 object: [1, 2, abc ]
463 3. With brackets: {min-spaces-inside-empty: 0, max-spaces-inside-empty:
465 0}
466 the following code snippet would PASS:
468 object: []
470 the following code snippet would FAIL:
472 object: [ ]
474 4. With brackets: {min-spaces-inside-empty: 1, max-spaces-inside-empty:
476 -1}
477 the following code snippet would PASS:
479 object: [ ]
481 the following code snippet would FAIL:
483 object: []
485 colons
487 Use this rule to control the number of spaces before and after colons
488 (:). Options.INDENT 0.0
489 · max-spaces-before defines the maximal number of spaces allowed before
491 colons (use -1 to disable).
492 · max-spaces-after defines the maximal number of spaces allowed after
494 colons (use -1 to disable).
495Examples.INDENT 0.0
496 1. With colons: {max-spaces-before: 0, max-spaces-after: 1}
498 the following code snippet would PASS:
500 object:
502 - a
503 - b
504 key: value
505 2. With colons: {max-spaces-before: 1}
507 the following code snippet would PASS:
509 object :
511 - a
512 - b
513 the following code snippet would FAIL:
515 object :
517 - a
518 - b
519 3. With colons: {max-spaces-after: 2}
521 the following code snippet would PASS:
523 first: 1
525 second: 2
526 third: 3
527 the following code snippet would FAIL:
529 first: 1
531 2nd: 2
532 third: 3
533 commas
535 Use this rule to control the number of spaces before and after commas
536 (,). Options.INDENT 0.0
537 · max-spaces-before defines the maximal number of spaces allowed before
539 commas (use -1 to disable).
540 · min-spaces-after defines the minimal number of spaces required after
542 commas.
543 · max-spaces-after defines the maximal number of spaces allowed after
545 commas (use -1 to disable).
546Examples.INDENT 0.0
547 1. With commas: {max-spaces-before: 0}
549 the following code snippet would PASS:
551 strange var:
553 [10, 20, 30, {x: 1, y: 2}]
554 the following code snippet would FAIL:
556 strange var:
558 [10, 20 , 30, {x: 1, y: 2}]
559 2. With commas: {max-spaces-before: 2}
561 the following code snippet would PASS:
563 strange var:
565 [10 , 20 , 30, {x: 1 , y: 2}]
566 3. With commas: {max-spaces-before: -1}
568 the following code snippet would PASS:
570 strange var:
572 [10,
573 20 , 30
574 , {x: 1, y: 2}]
575 4. With commas: {min-spaces-after: 1, max-spaces-after: 1}
577 the following code snippet would PASS:
579 strange var:
581 [10, 20,30, {x: 1, y: 2}]
582 the following code snippet would FAIL:
584 strange var:
586 [10, 20,30, {x: 1, y: 2}]
587 5. With commas: {min-spaces-after: 1, max-spaces-after: 3}
589 the following code snippet would PASS:
591 strange var:
593 [10, 20, 30, {x: 1, y: 2}]
594 6. With commas: {min-spaces-after: 0, max-spaces-after: 1}
596 the following code snippet would PASS:
598 strange var:
600 [10, 20,30, {x: 1, y: 2}]
601 comments
603 Use this rule to control the position and formatting of comments.
604 Options.INDENT 0.0
605 · Use require-starting-space to require a space character right after
607 the #. Set to true to enable, false to disable.
608 · Use ignore-shebangs to ignore a shebang at the beginning of the file
610 when require-starting-space is set.
611 · min-spaces-from-content is used to visually separate inline comments
613 from content. It defines the minimal required number of spaces
614 between a comment and its preceding content.
615Examples.INDENT 0.0
616 1. With comments: {require-starting-space: true}
618 the following code snippet would PASS:
620 # This sentence
622 # is a block comment
623 the following code snippet would PASS:
625 ##############################
627 ## This is some documentation
628 the following code snippet would FAIL:
630 #This sentence
632 #is a block comment
633 2. With comments: {min-spaces-from-content: 2}
635 the following code snippet would PASS:
637 x = 2 ^ 127 - 1 # Mersenne prime number
639 the following code snippet would FAIL:
641 x = 2 ^ 127 - 1 # Mersenne prime number
643 comments-indentation
645 Use this rule to force comments to be indented like content. Exam‐
646 ples.INDENT 0.0
647 1. With comments-indentation: {}
649 the following code snippet would PASS:
651 # Fibonacci
653 [0, 1, 1, 2, 3, 5]
654 the following code snippet would FAIL:
656 # Fibonacci
658 [0, 1, 1, 2, 3, 5]
659 the following code snippet would PASS:
661 list:
663 - 2
664 - 3
665 # - 4
666 - 5
667 the following code snippet would FAIL:
669 list:
671 - 2
672 - 3
673 # - 4
674 - 5
675 the following code snippet would PASS:
677 # This is the first object
679 obj1:
680 - item A
681 # - item B
682 # This is the second object
683 obj2: []
684 the following code snippet would PASS:
686 # This sentence
688 # is a block comment
689 the following code snippet would FAIL:
691 # This sentence
693 # is a block comment
694 document-end
696 Use this rule to require or forbid the use of document end marker
697 (...). Options.INDENT 0.0
698 · Set present to true when the document end marker is required, or to
700 false when it is forbidden.
701Examples.INDENT 0.0
702 1. With document-end: {present: true}
704 the following code snippet would PASS:
706 ---
708 this:
709 is: [a, document]
710 ...
711 ---
712 - this
713 - is: another one
714 ...
715 the following code snippet would FAIL:
717 ---
719 this:
720 is: [a, document]
721 ---
722 - this
723 - is: another one
724 ...
725 2. With document-end: {present: false}
727 the following code snippet would PASS:
729 ---
731 this:
732 is: [a, document]
733 ---
734 - this
735 - is: another one
736 the following code snippet would FAIL:
738 ---
740 this:
741 is: [a, document]
742 ...
743 ---
744 - this
745 - is: another one
746 document-start
748 Use this rule to require or forbid the use of document start marker
749 (---). Options.INDENT 0.0
750 · Set present to true when the document start marker is required, or to
752 false when it is forbidden.
753Examples.INDENT 0.0
754 1. With document-start: {present: true}
756 the following code snippet would PASS:
758 ---
760 this:
761 is: [a, document]
762 ---
763 - this
764 - is: another one
765 the following code snippet would FAIL:
767 this:
769 is: [a, document]
770 ---
771 - this
772 - is: another one
773 2. With document-start: {present: false}
775 the following code snippet would PASS:
777 this:
779 is: [a, document]
780 ...
781 the following code snippet would FAIL:
783 ---
785 this:
786 is: [a, document]
787 ...
788 empty-lines
790 Use this rule to set a maximal number of allowed consecutive blank
791 lines. Options.INDENT 0.0
792 · max defines the maximal number of empty lines allowed in the docu‐
794 ment.
795 · max-start defines the maximal number of empty lines allowed at the
797 beginning of the file. This option takes precedence over max.
798 · max-end defines the maximal number of empty lines allowed at the end
800 of the file. This option takes precedence over max.
801Examples.INDENT 0.0
802 1. With empty-lines: {max: 1}
804 the following code snippet would PASS:
806 - foo:
808 - 1
809 - 2
810 - bar: [3, 4]
812 the following code snippet would FAIL:
814 - foo:
816 - 1
817 - 2
818 - bar: [3, 4]
821 empty-values
823 Use this rule to prevent nodes with empty content, that implicitly
824 result in null values. Options.INDENT 0.0
825 · Use forbid-in-block-mappings to prevent empty values in block map‐
827 pings.
828 · Use forbid-in-flow-mappings to prevent empty values in flow mappings.
830Examples.INDENT 0.0
831 1. With empty-values: {forbid-in-block-mappings: true}
833 the following code snippets would PASS:
835 some-mapping:
837 sub-element: correctly indented
838 explicitly-null: null
840 the following code snippets would FAIL:
842 some-mapping:
844 sub-element: incorrectly indented
845 implicitly-null:
847 2. With empty-values: {forbid-in-flow-mappings: true}
849 the following code snippet would PASS:
851 {prop: null}
853 {a: 1, b: 2, c: 3}
854 the following code snippets would FAIL:
856 {prop: }
858 {a: 1, b:, c: 3}
860 hyphens
862 Use this rule to control the number of spaces after hyphens (-).
863 Options.INDENT 0.0
864 · max-spaces-after defines the maximal number of spaces allowed after
866 hyphens.
867Examples.INDENT 0.0
868 1. With hyphens: {max-spaces-after: 1}
870 the following code snippet would PASS:
872 - first list:
874 - a
875 - b
876 - - 1
877 - 2
878 - 3
879 the following code snippet would FAIL:
881 - first list:
883 - a
884 - b
885 the following code snippet would FAIL:
887 - - 1
889 - 2
890 - 3
891 2. With hyphens: {max-spaces-after: 3}
893 the following code snippet would PASS:
895 - key
897 - key2
898 - key42
899 the following code snippet would FAIL:
901 - key
903 - key2
904 - key42
905 indentation
907 Use this rule to control the indentation. Options.INDENT 0.0
908 · spaces defines the indentation width, in spaces. Set either to an
910 integer (e.g. 2 or 4, representing the number of spaces in an inden‐
911 tation level) or to consistent to allow any number, as long as it
912 remains the same within the file.
913 · indent-sequences defines whether block sequences should be indented
915 or not (when in a mapping, this indentation is not mandatory -- some
916 people perceive the - as part of the indentation). Possible values:
917 true, false, whatever and consistent. consistent requires either all
918 block sequences to be indented, or none to be. whatever means either
919 indenting or not indenting individual block sequences is OK.
920 · check-multi-line-strings defines whether to lint indentation in
922 multi-line strings. Set to true to enable, false to disable.
923Examples.INDENT 0.0
924 1. With indentation: {spaces: 1}
926 the following code snippet would PASS:
928 history:
930 - name: Unix
931 date: 1969
932 - name: Linux
933 date: 1991
934 nest:
935 recurse:
936 - haystack:
937 needle
938 2. With indentation: {spaces: 4}
940 the following code snippet would PASS:
942 history:
944 - name: Unix
945 date: 1969
946 - name: Linux
947 date: 1991
948 nest:
949 recurse:
950 - haystack:
951 needle
952 the following code snippet would FAIL:
954 history:
956 - name: Unix
957 date: 1969
958 - name: Linux
959 date: 1991
960 nest:
961 recurse:
962 - haystack:
963 needle
964 3. With indentation: {spaces: consistent}
966 the following code snippet would PASS:
968 history:
970 - name: Unix
971 date: 1969
972 - name: Linux
973 date: 1991
974 nest:
975 recurse:
976 - haystack:
977 needle
978 the following code snippet would FAIL:
980 some:
982 Russian:
983 dolls
984 4. With indentation: {spaces: 2, indent-sequences: false}
986 the following code snippet would PASS:
988 list:
990 - flying
991 - spaghetti
992 - monster
993 the following code snippet would FAIL:
995 list:
997 - flying
998 - spaghetti
999 - monster
1000 5. With indentation: {spaces: 2, indent-sequences: whatever}
1002 the following code snippet would PASS:
1004 list:
1006 - flying:
1007 - spaghetti
1008 - monster
1009 - not flying:
1010 - spaghetti
1011 - sauce
1012 6. With indentation: {spaces: 2, indent-sequences: consistent}
1014 the following code snippet would PASS:
1016 - flying:
1018 - spaghetti
1019 - monster
1020 - not flying:
1021 - spaghetti
1022 - sauce
1023 the following code snippet would FAIL:
1025 - flying:
1027 - spaghetti
1028 - monster
1029 - not flying:
1030 - spaghetti
1031 - sauce
1032 7. With indentation: {spaces: 4, check-multi-line-strings: true}
1034 the following code snippet would PASS:
1036 Blaise Pascal:
1038 Je vous écris une longue lettre parce que
1039 je n'ai pas le temps d'en écrire une courte.
1040 the following code snippet would PASS:
1042 Blaise Pascal: Je vous écris une longue lettre parce que
1044 je n'ai pas le temps d'en écrire une courte.
1045 the following code snippet would FAIL:
1047 Blaise Pascal: Je vous écris une longue lettre parce que
1049 je n'ai pas le temps d'en écrire une courte.
1050 the following code snippet would FAIL:
1052 C code:
1054 void main() {
1055 printf("foo");
1056 }
1057 the following code snippet would PASS:
1059 C code:
1061 void main() {
1062 printf("bar");
1063 }
1064 key-duplicates
1066 Use this rule to prevent multiple entries with the same key in map‐
1067 pings. Examples.INDENT 0.0
1068 1. With key-duplicates: {}
1070 the following code snippet would PASS:
1072 - key 1: v
1074 key 2: val
1075 key 3: value
1076 - {a: 1, b: 2, c: 3}
1077 the following code snippet would FAIL:
1079 - key 1: v
1081 key 2: val
1082 key 1: value
1083 the following code snippet would FAIL:
1085 - {a: 1, b: 2, b: 3}
1087 the following code snippet would FAIL:
1089 duplicated key: 1
1091 "duplicated key": 2
1092 other duplication: 1
1094 ? >-
1095 other
1096 duplication
1097 : 2
1098 key-ordering
1100 Use this rule to enforce alphabetical ordering of keys in mappings. The
1101 sorting order uses the Unicode code point number. As a result, the
1102 ordering is case-sensitive and not accent-friendly (see examples
1103 below). Examples.INDENT 0.0
1104 1. With key-ordering: {}
1106 the following code snippet would PASS:
1108 - key 1: v
1110 key 2: val
1111 key 3: value
1112 - {a: 1, b: 2, c: 3}
1113 - T-shirt: 1
1114 T-shirts: 2
1115 t-shirt: 3
1116 t-shirts: 4
1117 - hair: true
1118 hais: true
1119 haïr: true
1120 haïssable: true
1121 the following code snippet would FAIL:
1123 - key 2: v
1125 key 1: val
1126 the following code snippet would FAIL:
1128 - {b: 1, a: 2}
1130 the following code snippet would FAIL:
1132 - T-shirt: 1
1134 t-shirt: 2
1135 T-shirts: 3
1136 t-shirts: 4
1137 the following code snippet would FAIL:
1139 - haïr: true
1141 hais: true
1142 line-length
1144 Use this rule to set a limit to lines length.
1145 Note: with Python 2, the line-length rule may not work properly with
1147 unicode characters because of the way strings are represented in bytes.
1148 We recommend running yamllint with Python 3. Options.INDENT 0.0
1149 · max defines the maximal (inclusive) length of lines.
1151 · allow-non-breakable-words is used to allow non breakable words (with‐
1153 out spaces inside) to overflow the limit. This is useful for long
1154 URLs, for instance. Use true to allow, false to forbid.
1155 · allow-non-breakable-inline-mappings implies allow-non-breakable-words
1157 and extends it to also allow non-breakable words in inline mappings.
1158Examples.INDENT 0.0
1159 1. With line-length: {max: 70}
1161 the following code snippet would PASS:
1163 long sentence:
1165 Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do
1166 eiusmod tempor incididunt ut labore et dolore magna aliqua.
1167 the following code snippet would FAIL:
1169 long sentence:
1171 Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod
1172 tempor incididunt ut labore et dolore magna aliqua.
1173 2. With line-length: {max: 60, allow-non-breakable-words: true}
1175 the following code snippet would PASS:
1177 this:
1179 is:
1180 - a:
1181 http://localhost/very/very/very/very/very/very/very/very/long/url
1182 # this comment is too long,
1184 # but hard to split:
1185 # http://localhost/another/very/very/very/very/very/very/very/very/long/url
1186 the following code snippet would FAIL:
1188 - this line is waaaaaaaaaaaaaay too long but could be easily split...
1190 and the following code snippet would also FAIL:
1192 - foobar: http://localhost/very/very/very/very/very/very/very/very/long/url
1194 3. With line-length: {max: 60, allow-non-breakable-words: true,
1196 allow-non-breakable-inline-mappings: true}
1197 the following code snippet would PASS:
1199 - foobar: http://localhost/very/very/very/very/very/very/very/very/long/url
1201 4. With line-length: {max: 60, allow-non-breakable-words: false}
1203 the following code snippet would FAIL:
1205 this:
1207 is:
1208 - a:
1209 http://localhost/very/very/very/very/very/very/very/very/long/url
1210 new-line-at-end-of-file
1212 Use this rule to require a new line character (\n) at the end of files.
1213 The POSIX standard requires the last line to end with a new line char‐
1215 acter. All UNIX tools expect a new line at the end of files. Most text
1216 editors use this convention too.
1217 new-lines
1219 Use this rule to force the type of new line characters. Options.INDENT
1220 0.0
1221 · Set type to unix to use UNIX-typed new line characters (\n), or dos
1223 to use DOS-typed new line characters (\r\n).
1224 octal-values
1226 Use this rule to prevent values with octal numbers. In YAML, numbers
1227 that start with 0 are interpreted as octal, but this is not always
1228 wanted. For instance 010 is the city code of Beijing, and should not
1229 be converted to 8. Examples.INDENT 0.0
1230 1. With octal-values: {forbid-implicit-octal: true}
1232 the following code snippets would PASS:
1234 user:
1236 city-code: '010'
1237 the following code snippets would PASS:
1239 user:
1241 city-code: 010,021
1242 the following code snippets would FAIL:
1244 user:
1246 city-code: 010
1247 2. With octal-values: {forbid-explicit-octal: true}
1249 the following code snippets would PASS:
1251 user:
1253 city-code: '0o10'
1254 the following code snippets would FAIL:
1256 user:
1258 city-code: 0o10
1259 quoted-strings
1261 Use this rule to forbid any string values that are not quoted. You can
1262 also enforce the type of the quote used using the quote-type option
1263 (single, double or any).
1264 Note: Multi-line strings (with | or >) will not be checked. Exam‐
1266 ples.INDENT 0.0
1267 1. With quoted-strings: {quote-type: any}
1269 the following code snippet would PASS:
1271 foo: "bar"
1273 bar: 'foo'
1274 number: 123
1275 boolean: true
1276 the following code snippet would FAIL:
1278 foo: bar
1280 trailing-spaces
1282 Use this rule to forbid trailing spaces at the end of lines. Exam‐
1283 ples.INDENT 0.0
1284 1. With trailing-spaces: {}
1286 the following code snippet would PASS:
1288 this document doesn't contain
1290 any trailing
1291 spaces
1292 the following code snippet would FAIL:
1294 this document contains
1296 trailing spaces
1297 on lines 1 and 3
1298 truthy
1300 Use this rule to forbid non-explictly typed truthy values other than
1301 allowed ones (by default: true and false), for example YES or off.
1302 This can be useful to prevent surprises from YAML parsers transforming
1304 [yes, FALSE, Off] into [true, false, false] or {y: 1, yes: 2, on: 3,
1305 true: 4, True: 5} into {y: 1, true: 5}. Options.INDENT 0.0
1306 · allowed-values defines the list of truthy values which will be
1308 ignored during linting. The default is ['true', 'false'], but can be
1309 changed to any list containing: 'TRUE', 'True', 'true', 'FALSE',
1310 'False', 'false', 'YES', 'Yes', 'yes', 'NO', 'No', 'no', 'ON', 'On',
1311 'on', 'OFF', 'Off', 'off'.
1312Examples.INDENT 0.0
1313 1. With truthy: {}
1315 the following code snippet would PASS:
1317 boolean: true
1319 object: {"True": 1, 1: "True"}
1321 "yes": 1
1323 "on": 2
1324 "True": 3
1325 explicit:
1327 string1: !!str True
1328 string2: !!str yes
1329 string3: !!str off
1330 encoded: !!binary |
1331 True
1332 OFF
1333 pad== # this decodes as 'N»8Qii'
1334 boolean1: !!bool true
1335 boolean2: !!bool "false"
1336 boolean3: !!bool FALSE
1337 boolean4: !!bool True
1338 boolean5: !!bool off
1339 boolean6: !!bool NO
1340 the following code snippet would FAIL:
1342 object: {True: 1, 1: True}
1344 the following code snippet would FAIL:
1346 yes: 1
1348 on: 2
1349 True: 3
1350 2. With truthy: {allowed-values: ["yes", "no"]}
1352 the following code snippet would PASS:
1354 - yes
1356 - no
1357 - "true"
1358 - 'false'
1359 - foo
1360 - bar
1361 the following code snippet would FAIL:
1363 - true
1365 - false
1366 - on
1367 - off
1368 Disable with comments
1370 Disabling checks for a specific line
1371 To prevent yamllint from reporting problems for a specific line, add a
1372 directive comment (# yamllint disable-line ...) on that line, or on the
1373 line above. For instance:
1374 # The following mapping contains the same key twice,
1376 # but I know what I'm doing:
1377 key: value 1
1378 key: value 2 # yamllint disable-line rule:key-duplicates
1379 - This line is waaaaaaaaaay too long but yamllint will not report anything about it. # yamllint disable-line rule:line-length
1381 This line will be checked by yamllint.
1382 or:
1384 # The following mapping contains the same key twice,
1386 # but I know what I'm doing:
1387 key: value 1
1388 # yamllint disable-line rule:key-duplicates
1389 key: value 2
1390 # yamllint disable-line rule:line-length
1392 - This line is waaaaaaaaaay too long but yamllint will not report anything about it.
1393 This line will be checked by yamllint.
1394 It is possible, although not recommend, to disabled all rules for a
1396 specific line:
1397 # yamllint disable-line
1399 - { all : rules ,are disabled for this line}
1400 If you need to disable multiple rules, it is allowed to chain rules
1402 like this: # yamllint disable-line rule:hyphens rule:commas rule:inden‐
1403 tation.
1404 Disabling checks for all (or part of) the file
1406 To prevent yamllint from reporting problems for the whole file, or for
1407 a block of lines within the file, use # yamllint disable ... and # yam‐
1408 llint enable ... directive comments. For instance:
1409 # yamllint disable rule:colons
1411 - Lorem : ipsum
1412 dolor : sit amet,
1413 consectetur : adipiscing elit
1414 # yamllint enable rule:colons
1415 - rest of the document...
1417 It is possible, although not recommend, to disabled all rules:
1419 # yamllint disable
1421 - Lorem :
1422 ipsum:
1423 dolor : [ sit,amet]
1424 - consectetur : adipiscing elit
1425 # yamllint enable
1426 If you need to disable multiple rules, it is allowed to chain rules
1428 like this: # yamllint disable rule:hyphens rule:commas rule:indenta‐
1429 tion.
1430 Development
1432 yamllint provides both a script and a Python module. The latter can be
1433 used to write your own linting tools:
1434 class yamllint.linter.LintProblem(line, column, desc='<no descrip‐
1436 tion>', rule=None)
1437 Represents a linting problem found by yamllint.
1438 column = None
1440 Column on which the problem was found (starting at 1)
1441 desc = None
1443 Human-readable description of the problem
1444 line = None
1446 Line on which the problem was found (starting at 1)
1447 rule = None
1449 Identifier of the rule that detected the problem
1450 yamllint.linter.run(input, conf, filepath=None)
1452 Lints a YAML source.
1453 Returns a generator of LintProblem objects.
1455 Parameters
1457 · input -- buffer, string or stream to read from
1459 · conf -- yamllint configuration object
1461 Integration with text editors
1463 Most text editors support syntax checking and highlighting, to visually
1464 report syntax errors and warnings to the user. yamllint can be used to
1465 syntax-check YAML source, but a bit of configuration is required
1466 depending on your favorite text editor.
1467 Vim
1469 Assuming that the ALE plugin is installed, yamllint is supported by
1470 default. It is automatically enabled when editing YAML files.
1471 If you instead use the syntastic plugin, add this to your .vimrc:
1473 let g:syntastic_yaml_checkers = ['yamllint']
1475 Neovim
1477 Assuming that the neomake plugin is installed, yamllint is supported by
1478 default. It is automatically enabled when editing YAML files.
1479 Emacs
1481 If you are flycheck user, you can use flycheck-yamllint integration.
1482 Other text editors
1484 Help wanted!
1485 Your favorite text editor is not listed here? Help us improve by adding
1487 a section (by opening a pull-request or issue on GitHub).
1488 Integration with other software
1490 Integration with pre-commit
1491 You can integrate yamllint in pre-commit tool. Here is an example, to
1492 add in your .pre-commit-config.yaml
1493 ---
1495 # Update the sha variable with the release version that you want, from the yamllint repo
1496 - repo: https://github.com/adrienverge/yamllint.git
1497 sha: v1.8.1
1498 hooks:
1499 - id: yamllint
1500
1502 Adrien Vergé
1503
1505 Copyright 2016, Adrien Vergé
15061.16.0 Jun 07, 2019 YAMLLINT(1)