From f05f966a0824b1d302ee556183e2579c91954266 Mon Sep 17 00:00:00 2001 From: takanuva15 <6986426+takanuva15@users.noreply.github.com> Date: Sat, 21 Sep 2024 11:24:18 -0400 Subject: [PATCH] feat(form): Support default values for collections in form binding (#4048) --- binding/form_mapping.go | 20 +++++++++++ binding/form_mapping_test.go | 66 ++++++++++++++++++++++++++++++++++++ docs/doc.md | 48 ++++++++++++++++++++++++++ 3 files changed, 134 insertions(+) diff --git a/binding/form_mapping.go b/binding/form_mapping.go index a84536f7..f5f6f3ae 100644 --- a/binding/form_mapping.go +++ b/binding/form_mapping.go @@ -159,6 +159,14 @@ func tryToSetValue(value reflect.Value, field reflect.StructField, setter setter if k, v := head(opt, "="); k == "default" { setOpt.isDefaultExists = true setOpt.defaultValue = v + + // convert semicolon-separated default values to csv-separated values for processing in setByForm + if field.Type.Kind() == reflect.Slice || field.Type.Kind() == reflect.Array { + cfTag := field.Tag.Get("collection_format") + if cfTag == "" || cfTag == "multi" || cfTag == "csv" { + setOpt.defaultValue = strings.ReplaceAll(v, ";", ",") + } + } } } @@ -224,6 +232,12 @@ func setByForm(value reflect.Value, field reflect.StructField, form map[string][ case reflect.Slice: if !ok { vs = []string{opt.defaultValue} + + // pre-process the default value for multi if present + cfTag := field.Tag.Get("collection_format") + if cfTag == "" || cfTag == "multi" { + vs = strings.Split(opt.defaultValue, ",") + } } if ok, err = trySetCustom(vs[0], value); ok { @@ -238,6 +252,12 @@ func setByForm(value reflect.Value, field reflect.StructField, form map[string][ case reflect.Array: if !ok { vs = []string{opt.defaultValue} + + // pre-process the default value for multi if present + cfTag := field.Tag.Get("collection_format") + if cfTag == "" || cfTag == "multi" { + vs = strings.Split(opt.defaultValue, ",") + } } if ok, err = trySetCustom(vs[0], value); ok { diff --git a/binding/form_mapping_test.go b/binding/form_mapping_test.go index 8cf74651..810315bb 100644 --- a/binding/form_mapping_test.go +++ b/binding/form_mapping_test.go @@ -323,6 +323,72 @@ func TestMappingCollectionFormat(t *testing.T) { assert.Equal(t, [2]int{1, 2}, s.ArrayPipes) } +func TestMappingCollectionFormatInvalid(t *testing.T) { + var s struct { + SliceCsv []int `form:"slice_csv" collection_format:"xxx"` + } + err := mappingByPtr(&s, formSource{ + "slice_csv": {"1,2"}, + }, "form") + require.Error(t, err) + + var s2 struct { + ArrayCsv [2]int `form:"array_csv" collection_format:"xxx"` + } + err = mappingByPtr(&s2, formSource{ + "array_csv": {"1,2"}, + }, "form") + require.Error(t, err) +} + +func TestMappingMultipleDefaultWithCollectionFormat(t *testing.T) { + var s struct { + SliceMulti []int `form:",default=1;2;3" collection_format:"multi"` + SliceCsv []int `form:",default=1;2;3" collection_format:"csv"` + SliceSsv []int `form:",default=1 2 3" collection_format:"ssv"` + SliceTsv []int `form:",default=1\t2\t3" collection_format:"tsv"` + SlicePipes []int `form:",default=1|2|3" collection_format:"pipes"` + ArrayMulti [2]int `form:",default=1;2" collection_format:"multi"` + ArrayCsv [2]int `form:",default=1;2" collection_format:"csv"` + ArraySsv [2]int `form:",default=1 2" collection_format:"ssv"` + ArrayTsv [2]int `form:",default=1\t2" collection_format:"tsv"` + ArrayPipes [2]int `form:",default=1|2" collection_format:"pipes"` + SliceStringMulti []string `form:",default=1;2;3" collection_format:"multi"` + SliceStringCsv []string `form:",default=1;2;3" collection_format:"csv"` + SliceStringSsv []string `form:",default=1 2 3" collection_format:"ssv"` + SliceStringTsv []string `form:",default=1\t2\t3" collection_format:"tsv"` + SliceStringPipes []string `form:",default=1|2|3" collection_format:"pipes"` + ArrayStringMulti [2]string `form:",default=1;2" collection_format:"multi"` + ArrayStringCsv [2]string `form:",default=1;2" collection_format:"csv"` + ArrayStringSsv [2]string `form:",default=1 2" collection_format:"ssv"` + ArrayStringTsv [2]string `form:",default=1\t2" collection_format:"tsv"` + ArrayStringPipes [2]string `form:",default=1|2" collection_format:"pipes"` + } + err := mappingByPtr(&s, formSource{}, "form") + require.NoError(t, err) + + assert.Equal(t, []int{1, 2, 3}, s.SliceMulti) + assert.Equal(t, []int{1, 2, 3}, s.SliceCsv) + assert.Equal(t, []int{1, 2, 3}, s.SliceSsv) + assert.Equal(t, []int{1, 2, 3}, s.SliceTsv) + assert.Equal(t, []int{1, 2, 3}, s.SlicePipes) + assert.Equal(t, [2]int{1, 2}, s.ArrayMulti) + assert.Equal(t, [2]int{1, 2}, s.ArrayCsv) + assert.Equal(t, [2]int{1, 2}, s.ArraySsv) + assert.Equal(t, [2]int{1, 2}, s.ArrayTsv) + assert.Equal(t, [2]int{1, 2}, s.ArrayPipes) + assert.Equal(t, []string{"1", "2", "3"}, s.SliceStringMulti) + assert.Equal(t, []string{"1", "2", "3"}, s.SliceStringCsv) + assert.Equal(t, []string{"1", "2", "3"}, s.SliceStringSsv) + assert.Equal(t, []string{"1", "2", "3"}, s.SliceStringTsv) + assert.Equal(t, []string{"1", "2", "3"}, s.SliceStringPipes) + assert.Equal(t, [2]string{"1", "2"}, s.ArrayStringMulti) + assert.Equal(t, [2]string{"1", "2"}, s.ArrayStringCsv) + assert.Equal(t, [2]string{"1", "2"}, s.ArrayStringSsv) + assert.Equal(t, [2]string{"1", "2"}, s.ArrayStringTsv) + assert.Equal(t, [2]string{"1", "2"}, s.ArrayStringPipes) +} + func TestMappingStructField(t *testing.T) { var s struct { J struct { diff --git a/docs/doc.md b/docs/doc.md index 875dd619..8cb53cc2 100644 --- a/docs/doc.md +++ b/docs/doc.md @@ -26,6 +26,7 @@ - [Custom Validators](#custom-validators) - [Only Bind Query String](#only-bind-query-string) - [Bind Query String or Post Data](#bind-query-string-or-post-data) + - [Bind default value if none provided](#bind-default-value-if-none-provided) - [Collection format for arrays](#collection-format-for-arrays) - [Bind Uri](#bind-uri) - [Bind custom unmarshaler](#bind-custom-unmarshaler) @@ -862,6 +863,53 @@ Test it with: curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15&createTime=1562400033000000123&unixTime=1562400033" ``` + +### Bind default value if none provided + +If the server should bind a default value to a field when the client does not provide one, specify the default value using the `default` key within the `form` tag: + +``` +package main + +import ( + "net/http" + + "github.com/gin-gonic/gin" +) + +type Person struct { + Name string `form:"name,default=William"` + Age int `form:"age,default=10"` + Friends []string `form:"friends,default=Will;Bill"` + Addresses [2]string `form:"addresses,default=foo bar" collection_format:"ssv"` + LapTimes []int `form:"lap_times,default=1;2;3" collection_format:"csv"` +} + +func main() { + g := gin.Default() + g.POST("/person", func(c *gin.Context) { + var req Person + if err := c.ShouldBindQuery(&req); err != nil { + c.JSON(http.StatusBadRequest, err) + return + } + c.JSON(http.StatusOK, req) + }) + _ = g.Run("localhost:8080") +} +``` + +``` +curl -X POST http://localhost:8080/person +{"Name":"William","Age":10,"Friends":["Will","Bill"],"Colors":["red","blue"],"LapTimes":[1,2,3]} +``` + +NOTE: For default [collection values](#collection-format-for-arrays), the following rules apply: +- Since commas are used to delimit tag options, they are not supported within a default value and will result in undefined behavior +- For the collection formats "multi" and "csv", a semicolon should be used in place of a comma to delimited default values +- Since semicolons are used to delimit default values for "multi" and "csv", they are not supported within a default value for "multi" and "csv" + + #### Collection format for arrays | Format | Description | Example |