{"id":5162,"date":"2021-02-27T00:20:16","date_gmt":"2021-02-26T18:50:16","guid":{"rendered":"https:\/\/golangbyexamples.com\/?p=5162"},"modified":"2021-02-27T00:20:25","modified_gmt":"2021-02-26T18:50:25","slug":"range-int-struct-validate-golang","status":"publish","type":"post","link":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/","title":{"rendered":"Validate the range of the integer in a struct in Go (Golang)"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_17 counter-hierarchy counter-decimal ez-toc-light-blue\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" style=\"display: none;\"><i class=\"ez-toc-glyphicon ez-toc-icon-toggle\"><\/i><\/a><\/span><\/div>\n<nav><ul class=\"ez-toc-list ez-toc-list-level-1\"><li class=\"ez-toc-page-1 ez-toc-heading-level-1\"><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#Overview\" title=\"Overview\">Overview<\/a><\/li><li class=\"ez-toc-page-1 ez-toc-heading-level-1\"><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#Example\" title=\"Example\">Example<\/a><\/li><\/ul><\/nav><\/div>\n<h1 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Overview\"><\/span><strong>Overview<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<p class=\"has-medium-font-size\">The below library can be used to validate the range of an integer in a struct in Golang<\/p>\n\n\n\n<ul class=\"has-medium-font-size wp-block-list\"><li><strong>gopkg.in\/go-playground\/validator.v9<\/strong> &#8211; <a href=\"https:\/\/pkg.go.dev\/github.com\/go-playground\/validator\">https:\/\/pkg.go.dev\/github.com\/go-playground\/validator<\/a><\/li><\/ul>\n\n\n\n<p class=\"has-medium-font-size\">For this tutorial, we will use the below employee struct<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">type employee struct {\n    Age int\n}<\/code><\/pre>\n\n\n\n<h1 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Example\"><\/span><strong>Example<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<p class=\"has-medium-font-size\">Let&#8217;s see an example for the same. Below is the code<\/p>\n\n\n\n<p class=\"has-medium-font-size\"><strong>go.mod<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">module sample.com\/validate\ngo 1.14\nrequire (\n    github.com\/go-playground\/universal-translator v0.17.0 \/\/ indirect\n    github.com\/leodido\/go-urn v1.2.1 \/\/ indirect\n    gopkg.in\/go-playground\/assert.v1 v1.2.1 \/\/ indirect\n    gopkg.in\/go-playground\/validator.v9 v9.31.0\n)<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\"><strong>main.go<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">package main\nimport (\n    \"fmt\"\n    \"gopkg.in\/go-playground\/validator.v9\"\n)\nvar validate *validator.Validate\ntype employee struct {\n    Age int `validate:\"required,gte=10,lte=20\"`\n}\nfunc main() {\n    e := employee{}\n    err := validateStruct(e)\n    if err != nil {\n        fmt.Printf(\"Error: %s\\n\", err)\n    }\n    e = employee{Age: 5}\n    err = validateStruct(e)\n    if err != nil {\n        fmt.Printf(\"Error: %s\\n\", err)\n    }\n    e = employee{Age: 25}\n    err = validateStruct(e)\n    if err != nil {\n        fmt.Printf(\"Error: %s\\n\", err)\n    }\n}\nfunc validateStruct(e employee) error {\n    validate = validator.New()\n    err := validate.Struct(e)\n    if err != nil {\n        return err\n    }\n    return nil\n}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\"><strong>Output<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">Error: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'required' tag\nError: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'gte' tag\nError: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'lte' tag<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">First, we need to declare the instance of Validate<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">var validate *validator.Validate<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">Notice here that we need to associate meta tags with fields of the struct to let the validator know that you want to validate this field. In the above example, we added the tag with the Age field. This tag is interpreted by the playground validate library. Notice we added three validations for the <strong>Age<\/strong> field<\/p>\n\n\n\n<ul class=\"has-medium-font-size wp-block-list\"><li><strong>required<\/strong> &#8211; validates that the field is present<\/li><\/ul>\n\n\n\n<ul class=\"has-medium-font-size wp-block-list\"><li><strong>gte<\/strong> &#8211; validate that the field value is greater than equal to a particular value<\/li><\/ul>\n\n\n\n<ul class=\"has-medium-font-size wp-block-list\"><li><strong>lte<\/strong> &#8211; validate that the field value is less than equal to a particular value<\/li><\/ul>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">type employee struct {\n\tAge int `validate:\"required,gte=10,lte=20\"`\n}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">Then call the Struct method to validate the struct<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">validate.Struct(e)<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">For<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">e := employee{}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">it gives the output as below is <strong>Age<\/strong> field is empty<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">Error: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'required' tag<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">For<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">e := employee{Age: 5}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">it gives the output as below as <strong>Age<\/strong> field value is 5 which is less than 10<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">Error: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'gte' tag<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">For<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">e := employee{Age: 25}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\">it gives the output as below as <strong>Age<\/strong> field value is 25 which is greater than 20<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">Error: Key: 'employee.Age' Error:Field validation for 'Age' failed on the 'lte' tag<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Table of Contents OverviewExample Overview The below library can be used to validate the range of an integer in a struct in Golang gopkg.in\/go-playground\/validator.v9 &#8211; https:\/\/pkg.go.dev\/github.com\/go-playground\/validator For this tutorial, we will use&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[1],"tags":[4,268,134,312],"class_list":["post-5162","post","type-post","status-publish","format-standard","hentry","category-tech","tag-golang","tag-gp","tag-range","tag-validation"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.7 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example\" \/>\n<meta property=\"og:description\" content=\"Table of Contents OverviewExample Overview The below library can be used to validate the range of an integer in a struct in Golang gopkg.in\/go-playground\/validator.v9 &#8211; https:\/\/pkg.go.dev\/github.com\/go-playground\/validator For this tutorial, we will use...\" \/>\n<meta property=\"og:url\" content=\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/\" \/>\n<meta property=\"og:site_name\" content=\"Welcome To Golang By Example\" \/>\n<meta property=\"article:published_time\" content=\"2021-02-26T18:50:16+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2021-02-26T18:50:25+00:00\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/\",\"url\":\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/\",\"name\":\"Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example\",\"isPartOf\":{\"@id\":\"https:\/\/golangbyexamples.com\/#website\"},\"datePublished\":\"2021-02-26T18:50:16+00:00\",\"dateModified\":\"2021-02-26T18:50:25+00:00\",\"author\":{\"@id\":\"https:\/\/golangbyexamples.com\/#\/schema\/person\/8833ea7638dafd763cb1db6c0ca4576f\"},\"breadcrumb\":{\"@id\":\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/golangbyexamples.com\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Validate the range of the integer in a struct in Go (Golang)\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/golangbyexamples.com\/#website\",\"url\":\"https:\/\/golangbyexamples.com\/\",\"name\":\"Welcome To Golang By Example\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/golangbyexamples.com\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/golangbyexamples.com\/#\/schema\/person\/8833ea7638dafd763cb1db6c0ca4576f\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/golangbyexamples.com\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g\",\"caption\":\"admin\"},\"url\":\"https:\/\/golangbyexamples.com\/author\/admin\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/","og_locale":"en_US","og_type":"article","og_title":"Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example","og_description":"Table of Contents OverviewExample Overview The below library can be used to validate the range of an integer in a struct in Golang gopkg.in\/go-playground\/validator.v9 &#8211; https:\/\/pkg.go.dev\/github.com\/go-playground\/validator For this tutorial, we will use...","og_url":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/","og_site_name":"Welcome To Golang By Example","article_published_time":"2021-02-26T18:50:16+00:00","article_modified_time":"2021-02-26T18:50:25+00:00","author":"admin","twitter_card":"summary_large_image","twitter_misc":{"Written by":"admin","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/","url":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/","name":"Validate the range of the integer in a struct in Go (Golang) - Welcome To Golang By Example","isPartOf":{"@id":"https:\/\/golangbyexamples.com\/#website"},"datePublished":"2021-02-26T18:50:16+00:00","dateModified":"2021-02-26T18:50:25+00:00","author":{"@id":"https:\/\/golangbyexamples.com\/#\/schema\/person\/8833ea7638dafd763cb1db6c0ca4576f"},"breadcrumb":{"@id":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/golangbyexamples.com\/range-int-struct-validate-golang\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/golangbyexamples.com\/"},{"@type":"ListItem","position":2,"name":"Validate the range of the integer in a struct in Go (Golang)"}]},{"@type":"WebSite","@id":"https:\/\/golangbyexamples.com\/#website","url":"https:\/\/golangbyexamples.com\/","name":"Welcome To Golang By Example","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/golangbyexamples.com\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/golangbyexamples.com\/#\/schema\/person\/8833ea7638dafd763cb1db6c0ca4576f","name":"admin","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/golangbyexamples.com\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","caption":"admin"},"url":"https:\/\/golangbyexamples.com\/author\/admin\/"}]}},"jetpack_featured_media_url":"","jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paOs1b-1lg","amp_validity":null,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/posts\/5162","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/comments?post=5162"}],"version-history":[{"count":1,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/posts\/5162\/revisions"}],"predecessor-version":[{"id":5163,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/posts\/5162\/revisions\/5163"}],"wp:attachment":[{"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/media?parent=5162"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/categories?post=5162"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/golangbyexamples.com\/wp-json\/wp\/v2\/tags?post=5162"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}