feat: replace govaluate with expr

AuHau · AuHau · Feb 7, 2022 · Feb 7, 2022 · Feb 7, 2022 · 10c08c93b73ab2ae38f88034338578315d7f9b2d
commit 10c08c93b73ab2ae38f88034338578315d7f9b2d
diff --git a/README.md b/README.md
@@ -63,7 +63,11 @@ The order of precedence is: $HOME config > CWD config > --config config > Env. v
 
 Parsing pattern
 ---------------
-The logs are parsed using parsing pattern that you have to configure in order to use filters. The lines are tokenized using space character so you have to define section of the line. Internally regex is used for parsing, but the input pattern is escaped by default for special characters so you don't have to worry about that. You define parameters using syntax "<name:type>", where name is the name of parameter that you can refer to in filters and type is predefined type used to correctly find and parse the parameter.
+The logs are parsed using parsing pattern that you have to configure in order to use filters. The lines are tokenized using space character. Internally regex is used for parsing, but the input pattern is escaped by default for special characters so you don't have to worry about special characters. You define parameters using syntax "<name:type>", where name is the name of parameter that you can refer to in filters and type is predefined type used to correctly find and parse the parameter.
+
+Lines that were not possible to parsed are colored with red color. Moreover counter of how many lines were not possible to parse is displayed in the status bar on the right end of it. It is only present if there are some lines that were not possible to parse.  
+
+There is built-in bool parameter called "patternMatches" reserved for marking log lines that were or were not possible to match against the parsing pattern. So you can use that to debug your parsing pattern with expressions like "!patternMatches"
 
 Supported types:
  - "string" defines string containing non-whitespace characters: [^\s]+
@@ -82,40 +86,49 @@ Filter
 ------
 In order to use filter for the logs you have to define parsing pattern in which you define parameters that are extracted from the log lines. Then you can write filter expressions that will be applied on the logs. Filter has to return bool otherwise error will be shown.
 
-loggy uses internally "govaluate" which has very rich set of C-like arithmetic/string expressions that you can use for your filters. Brief overview:
- - modifiers: + - / * & | ^ ** %% >> <<
- - comparators: > >= < <= == != =~ !~
- - logical ops: || &&
+loggy uses internally "expr" which has very rich set of arithmetic/string operators that you can use for your filters. Brief overview:
+ - modifiers: + - / * % **
+ - comparators: > >= < <= == !=
+ - logical ops: not ! or || and &&
  - numeric constants, as 64-bit floating point (12345.678)
- - string constants (single quotes: 'foobar')
- - date constants (single quotes, using any permutation of RFC3339, ISO8601, ruby date, or unix date; date parsing is automatically tried with any string constant)
+ - numeric range: '..' (18..45) 
+ - string constants (single or double quotes)
+ - string operators: + matches contains startsWith endsWith
  - boolean constants: true false
  - parenthesis to control order of evaluation ( )
- - arrays (anything separated by , within parenthesis: (1, 2, 'foo'))
- - prefixes: ! - ~
+ - arrays e.g. [1, 2, 3]
+ - maps - e.g. {foo: "bar"}
  - ternary conditional: ? :
- - null coalescence: ??
+ - built in functions: len() all() none() any() one() filter() map() count()
 
-For more details see: https://github.com/Knetic/govaluate/blob/master/MANUAL.md
+For more details see: https://github.com/antonmedv/expr/blob/master/docs/Language-Definition.md
 
 Example of filter for the parsing pattern log above:
 level == "DEBUG" - display only debug messages
-code > 400 - display logs with code higher then 400
+code in 400..500 - display logs with code in range from 400 to 500 (inclusive)
 
 Keyboard shortcuts
 ------------------
-General keys:
+
+Status bar on top displays several helpful information. Describing from left to right:
+ - Input name
+ - Optional "F" indicator that shows if loggy is following the end of the logs
+ - Filter status that displays "<number of filter matching lines>/<number of total lines>". If it has green background than filter is applied otherwise is turned off or not set.
+ - Optional number of lines that were not possible to match against the parsing pattern.s
+
+Main key shortcuts:
  - "/" for setting filter
  - "f" for toggling filter
  - "p" for setting parsing pattern input
- - "b" for scroll to bottom and follow new data
  - "h" for displaying help
 
 Logs navigation:
  - "j", "k" or arrow keys for scrolling by one line 
- - "g", "G" to move to top / bottom
+ - "g" to move to top
+ - "G" to move to bottom and follow bottom
  - "Ctrl-F", "page down" to move down by one page
  - "Ctrl-B", "page up" to move up by one page
+ - Mouse scrolling also scrolls the view accordingly
 
 Input fields:
  - Left arrow: Move left by one character.
@@ -136,6 +149,7 @@ Usage:
 Flags:
   -b, --buffer-size int       number of lines that will be buffered (default 10000)
       --config string         config file (default is $HOME/.loggy.yaml)
+  -f, --follow                turn on following mode which always show latest logs
   -h, --help                  help for loggy
   -p, --pattern string        parsing pattern see above for details
   -n, --pattern-name string   use predefined pattern in config

diff --git a/go.mod b/go.mod
@@ -3,7 +3,7 @@ module github.com/auhau/loggy
 go 1.17
 
 require (
-	github.com/Knetic/govaluate v3.0.0+incompatible
+	github.com/antonmedv/expr v1.9.0
 	github.com/auhau/allot v0.0.0-20220131141522-754325320dd5
 	github.com/auhau/gredux v0.0.0-20220204125146-c2f415ee87de
 	github.com/chonla/format v0.0.0-20220105105701-1119f4a3f36f

diff --git a/go.sum b/go.sum
@@ -51,15 +51,16 @@ cloud.google.com/go/storage v1.14.0/go.mod h1:GrKmX003DSIwi9o29oFT7YDnHYwZoctc3f
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/DATA-DOG/go-sqlmock v1.3.3/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM=
 github.com/DataDog/datadog-go v3.2.0+incompatible/go.mod h1:LButxg5PwREeZtORoXG3tL4fMGNddJ+vMq1mwgfaqoQ=
-github.com/Knetic/govaluate v3.0.0+incompatible h1:7o6+MAPhYTCF0+fdvoz1xDedhRb4f6s9Tn1Tt7/WTEg=
-github.com/Knetic/govaluate v3.0.0+incompatible/go.mod h1:r7JcOSlj0wfOMncg0iLm8Leh48TZaKVeNIfJntJ2wa0=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/alecthomas/units v0.0.0-20190717042225-c3de453c63f4/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
+github.com/antonmedv/expr v1.9.0 h1:j4HI3NHEdgDnN9p6oI6Ndr0G5QryMY0FNxT4ONrFDGU=
+github.com/antonmedv/expr v1.9.0/go.mod h1:5qsM3oLGDND7sDmQGDXHkYfkjYMUX14qsgqmHhwGEk8=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
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 github.com/armon/go-metrics v0.3.10/go.mod h1:4O98XIr/9W0sxpJ8UaYkvjk10Iff7SnFrb4QAOwNTFc=
@@ -99,6 +100,7 @@ github.com/cncf/xds/go v0.0.0-20211130200136-a8f946100490/go.mod h1:eXthEFrGJvWH
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-systemd/v22 v22.3.2/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/cpuguy83/go-md2man/v2 v2.0.1/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/davecgh/go-spew v0.0.0-20161028175848-04cdfd42973b/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
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 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -120,6 +122,8 @@ github.com/fsnotify/fsnotify v1.5.1 h1:mZcQUHVQUQWoPXXtuf9yuEXKudkV2sx1E06UadKWp
 github.com/fsnotify/fsnotify v1.5.1/go.mod h1:T3375wBYaZdLLcVNkcVbzGHY7f1l/uK5T5Ai1i3InKU=
 github.com/gdamore/encoding v1.0.0 h1:+7OoQ1Bc6eTm5niUzBa0Ctsh6JbMW6Ra+YNuAtDBdko=
 github.com/gdamore/encoding v1.0.0/go.mod h1:alR0ol34c49FCSBLjhosxzcPHQbf2trDkoo5dl+VrEg=
+github.com/gdamore/tcell v1.3.0 h1:r35w0JBADPZCVQijYebl6YMWWtHRqVEGt7kL2eBADRM=
+github.com/gdamore/tcell v1.3.0/go.mod h1:Hjvr+Ofd+gLglo7RYKxxnzCBmev3BzsS67MebKS4zMM=
 github.com/gdamore/tcell/v2 v2.4.1-0.20210905002822-f057f0a857a1 h1:QqwPZCwh/k1uYqq6uXSb9TRDhTkfQbO80v8zhnIe5zM=
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 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
@@ -263,6 +267,8 @@ github.com/kr/pretty v0.2.0/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfn
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
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+github.com/lucasb-eyer/go-colorful v1.0.2/go.mod h1:0MS4r+7BZKSJ5mw4/S5MPN+qHFF1fYclkSPilDOKW0s=
+github.com/lucasb-eyer/go-colorful v1.0.3/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
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 github.com/lyft/protoc-gen-star v0.5.3/go.mod h1:V0xaHgaf5oCCqmcxYcWiDfTiKsZsRc87/1qhoTACD8w=
@@ -279,6 +285,8 @@ github.com/mattn/go-isatty v0.0.10/go.mod h1:qgIWMr58cqv1PHHyhnkY9lrL7etaEgOFcME
 github.com/mattn/go-isatty v0.0.11/go.mod h1:PhnuNfih5lzO57/f3n+odYbM4JtupLOxQOAqxQCu2WE=
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+github.com/mattn/go-runewidth v0.0.4/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
+github.com/mattn/go-runewidth v0.0.8/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
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@@ -307,6 +315,7 @@ github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINE
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/sftp v1.10.1/go.mod h1:lYOWFsE0bwd1+KfKJaKeuokY15vzFx25BLbzYYoAxZI=
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+github.com/pmezard/go-difflib v0.0.0-20151028094244-d8ed2627bdf0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/posener/complete v1.1.1/go.mod h1:em0nMJCgc9GFtwrmVmEMR/ZL6WyhyjMBndrE9hABlRI=
@@ -323,8 +332,10 @@ github.com/prometheus/common v0.9.1/go.mod h1:yhUN8i9wzaXS3w1O07YhxHEBxD+W35wd8b
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
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+github.com/rivo/tview v0.0.0-20200219210816-cd38d7432498/go.mod h1:6lkG1x+13OShEf0EaOCaTQYyB7d5nSbb181KtjlS+84=
 github.com/rivo/tview v0.0.0-20220129131435-1f7581b67bd1 h1:rZQHaUDlzupPiNSXPKG+NwRvSm5I6gVS96xTOBoseWc=
 github.com/rivo/tview v0.0.0-20220129131435-1f7581b67bd1/go.mod h1:WIfMkQNY+oq/mWwtsjOYHIZBuwthioY2srOmljJkTnk=
+github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
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@@ -333,6 +344,7 @@ github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQD
 github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
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 github.com/sagikazarmark/crypt v0.4.0/go.mod h1:ALv2SRj7GxYV4HO9elxH9nS6M9gW+xDNxqmyJ6RfDFM=
+github.com/sanity-io/litter v1.2.0/go.mod h1:JF6pZUFgu2Q0sBZ+HSV35P8TVPI1TTzEwyu9FXAw2W4=
 github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529/go.mod h1:DxrIzT+xaE7yg65j358z/aeFdxmN0P9QXhEzd20vsDc=
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 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
@@ -354,6 +366,7 @@ github.com/spf13/viper v1.10.1 h1:nuJZuYpG7gTj/XqiUwg8bA0cp1+M2mC3J4g5luUYBKk=
 github.com/spf13/viper v1.10.1/go.mod h1:IGlFPqhNAPKRxohIzWpI5QEy4kuI7tcl5WvR+8qy1rU=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
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+github.com/stretchr/testify v0.0.0-20161117074351-18a02ba4a312/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
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@@ -515,6 +528,7 @@ golang.org/x/sys v0.0.0-20190502145724-3ef323f4f1fd/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190507160741-ecd444e8653b/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190606165138-5da285871e9c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190624142023-c5567b49c5d0/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190626150813-e07cf5db2756/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190922100055-0a153f010e69/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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diff --git a/state/state.go b/state/state.go
@@ -1,7 +1,7 @@
 package state
 
 import (
-	"github.com/Knetic/govaluate"
+	"github.com/antonmedv/expr/vm"
 	"github.com/auhau/allot"
 )
 
@@ -26,7 +26,7 @@ type State struct {
 
 	// InputFilter
 	FilterString       string
-	FilterExpression   *govaluate.EvaluableExpression
+	FilterExpression   *vm.Program
 	DisplayFilterInput bool
 
 	// PatternFilter

diff --git a/store/filter.go b/store/filter.go
@@ -1,19 +1,18 @@
 package store
 
 import (
-	"errors"
 	"fmt"
-	"github.com/Knetic/govaluate"
+	"github.com/antonmedv/expr"
+	"github.com/antonmedv/expr/vm"
 	"github.com/auhau/allot"
-	"reflect"
 	"strings"
 )
 
 const PATTERN_MATCHING_PARAMETER_NAME = "patternMatches"
 
 // Filter goes through buffer and writes out logs that match
 // It assumes that display was cleared out
-func Filter(filter *govaluate.EvaluableExpression, pattern allot.Command, nonPatternMatchingDecorator func(string) string) (totalLines, matchingLines, nonPatternLines int, logs string, err error) {
+func Filter(filter *vm.Program, pattern allot.Command, nonPatternMatchingDecorator func(string) string) (totalLines, matchingLines, nonPatternLines int, logs string, err error) {
 	mu.Lock()
 	defer mu.Unlock()
 	builder := strings.Builder{}
@@ -93,7 +92,7 @@ func buildParameters(match allot.MatchInterface, pattern allot.Command) (map[str
 
 // IsLineMatching check if for given filter and pattern the line matches.
 // It returns enum values FILTER_MATCH, PARSE_PATTERN_NO_MATCH or FILTER_NO_MATCH according it matching result
-func IsLineMatching(line string, filter *govaluate.EvaluableExpression, pattern allot.Command) (filterMatched bool, patternMatched bool, err error) {
+func IsLineMatching(line string, filter *vm.Program, pattern allot.Command) (filterMatched bool, patternMatched bool, err error) {
 	match, matchError := pattern.Match(line)
 
 	// if no filter is configured than we don't have to do filterExpression evaluation
@@ -118,15 +117,11 @@ func IsLineMatching(line string, filter *govaluate.EvaluableExpression, pattern
 		return false, false, err
 	}
 
-	result, err := filter.Evaluate(parameters)
+	result, err := expr.Run(filter, parameters)
 	if err != nil {
 		return false, false, err
 	}
 
-	if reflect.TypeOf(result).String() != "bool" {
-		return false, false, errors.New("filter expression did not return boolean")
-	}
-
 	if result.(bool) {
 		return true, matchError == nil, nil
 	}

diff --git a/ui/input_filter.go b/ui/input_filter.go
@@ -2,7 +2,8 @@ package ui
 
 import (
 	"fmt"
-	"github.com/Knetic/govaluate"
+	"github.com/antonmedv/expr"
+	"github.com/antonmedv/expr/vm"
 	"github.com/auhau/gredux"
 	"github.com/auhau/loggy/state"
 	"github.com/auhau/loggy/state/actions"
@@ -28,15 +29,15 @@ func filterInputReducer(s gredux.State, action gredux.Action) gredux.State {
 
 	case actions.ActionNameFilter:
 		var (
-			filterExpression *govaluate.EvaluableExpression
+			filterExpression *vm.Program
 			err              error
 			filterString     = action.Data.(string)
 		)
 
 		if filterString == "" {
 			filterExpression = nil
 		} else {
-			filterExpression, err = govaluate.NewEvaluableExpression(filterString)
+			filterExpression, err = expr.Compile(filterString, expr.AsBool())
 			if err != nil {
 				st.DisplayError = true
 				st.ErrorMessage = fmt.Sprint(err)

diff --git a/ui/input_pattern.go b/ui/input_pattern.go
@@ -29,6 +29,12 @@ func makeParsingPattern(pattern string) (parsingPatternInstance allot.Command, e
 		return parsingPatternInstance, fmt.Errorf("invalid syntax of parsing pattern: %s", err)
 	}
 
+	for _, parameter := range parsingPatternInstance.Parameters() {
+		if parameter.Name() == store.PATTERN_MATCHING_PARAMETER_NAME {
+			return parsingPatternInstance, fmt.Errorf("parsing pattern contains reserved pattern name '%s'", store.PATTERN_MATCHING_PARAMETER_NAME)
+		}
+	}
+
 	return parsingPatternInstance, nil
 }