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After go1.16, go will use module mode by default, even when the repository is checked out under GOPATH or in a one-off directory. Add go.mod, go.sum to keep this repo buildable without opting out of the module mode. > go mod init github.com/mmcgrana/gobyexample > go mod tidy > go mod vendor In module mode, the 'vendor' directory is special and its contents will be actively maintained by the go command. pygments aren't the dependency the go will know about, so it will delete the contents from vendor directory. Move it to `third_party` directory now. And, vendor the blackfriday package. Note: the tutorial contents are not affected by the change in go1.16 because all the examples in this tutorial ask users to run the go command with the explicit list of files to be compiled (e.g. `go run hello-world.go` or `go build command-line-arguments.go`). When the source list is provided, the go command does not have to compute the build list and whether it's running in GOPATH mode or module mode becomes irrelevant.
199 lines
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199 lines
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<!DOCTYPE html>
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<html>
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<head>
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<meta charset="utf-8">
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<title>Go by Example: Base64 Encoding</title>
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<link rel=stylesheet href="site.css">
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</head>
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<script>
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if (e.key == "ArrowLeft") {
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if (e.key == "ArrowRight") {
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window.location.href = 'reading-files';
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<body>
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<div class="example" id="base64-encoding">
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<h2><a href="./">Go by Example</a>: Base64 Encoding</h2>
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<table>
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<tr>
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<td class="docs">
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<p>Go provides built-in support for <a href="http://en.wikipedia.org/wiki/Base64">base64
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encoding/decoding</a>.</p>
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</td>
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<td class="code empty leading">
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</td>
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</tr>
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<tr>
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<td class="docs">
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</td>
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<td class="code leading">
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<a href="http://play.golang.org/p/S7ff3UgzNlG"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
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<div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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<p>This syntax imports the <code>encoding/base64</code> package with
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the <code>b64</code> name instead of the default <code>base64</code>. It’ll
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save us some space below.</p>
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</td>
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<td class="code leading">
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<div class="highlight"><pre><span class="kn">import</span> <span class="p">(</span>
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<span class="nx">b64</span> <span class="s">"encoding/base64"</span>
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<span class="s">"fmt"</span>
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<span class="p">)</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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</td>
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<td class="code leading">
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<div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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<p>Here’s the <code>string</code> we’ll encode/decode.</p>
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</td>
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<td class="code leading">
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<div class="highlight"><pre> <span class="nx">data</span> <span class="o">:=</span> <span class="s">"abc123!?$*&()'-=@~"</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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<p>Go supports both standard and URL-compatible
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base64. Here’s how to encode using the standard
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encoder. The encoder requires a <code>[]byte</code> so we
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convert our <code>string</code> to that type.</p>
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</td>
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<td class="code leading">
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<div class="highlight"><pre> <span class="nx">sEnc</span> <span class="o">:=</span> <span class="nx">b64</span><span class="p">.</span><span class="nx">StdEncoding</span><span class="p">.</span><span class="nx">EncodeToString</span><span class="p">([]</span><span class="nb">byte</span><span class="p">(</span><span class="nx">data</span><span class="p">))</span>
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<span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">sEnc</span><span class="p">)</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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<p>Decoding may return an error, which you can check
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if you don’t already know the input to be
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well-formed.</p>
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</td>
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<td class="code leading">
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<div class="highlight"><pre> <span class="nx">sDec</span><span class="p">,</span> <span class="nx">_</span> <span class="o">:=</span> <span class="nx">b64</span><span class="p">.</span><span class="nx">StdEncoding</span><span class="p">.</span><span class="nx">DecodeString</span><span class="p">(</span><span class="nx">sEnc</span><span class="p">)</span>
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<span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nb">string</span><span class="p">(</span><span class="nx">sDec</span><span class="p">))</span>
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<span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">()</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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<p>This encodes/decodes using a URL-compatible base64
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format.</p>
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</td>
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<td class="code">
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<div class="highlight"><pre> <span class="nx">uEnc</span> <span class="o">:=</span> <span class="nx">b64</span><span class="p">.</span><span class="nx">URLEncoding</span><span class="p">.</span><span class="nx">EncodeToString</span><span class="p">([]</span><span class="nb">byte</span><span class="p">(</span><span class="nx">data</span><span class="p">))</span>
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<span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">uEnc</span><span class="p">)</span>
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<span class="nx">uDec</span><span class="p">,</span> <span class="nx">_</span> <span class="o">:=</span> <span class="nx">b64</span><span class="p">.</span><span class="nx">URLEncoding</span><span class="p">.</span><span class="nx">DecodeString</span><span class="p">(</span><span class="nx">uEnc</span><span class="p">)</span>
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<span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nb">string</span><span class="p">(</span><span class="nx">uDec</span><span class="p">))</span>
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<span class="p">}</span>
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</pre></div>
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</td>
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</tr>
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</table>
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<table>
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<tr>
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<td class="docs">
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<p>The string encodes to slightly different values with the
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standard and URL base64 encoders (trailing <code>+</code> vs <code>-</code>)
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but they both decode to the original string as desired.</p>
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</td>
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<td class="code leading">
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<div class="highlight"><pre><span class="gp">$</span> go run base64-encoding.go
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<span class="go">YWJjMTIzIT8kKiYoKSctPUB+</span>
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<span class="go">abc123!?$*&()'-=@~</span>
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</pre></div>
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</td>
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</tr>
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<tr>
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<td class="docs">
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</td>
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<td class="code">
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<div class="highlight"><pre><span class="go">YWJjMTIzIT8kKiYoKSctPUB-</span>
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<span class="go">abc123!?$*&()'-=@~</span>
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</pre></div>
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</td>
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</tr>
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</table>
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<p class="next">
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Next example: <a href="reading-files">Reading Files</a>.
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</p>
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<p class="footer">
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by <a href="https://markmcgranaghan.com">Mark McGranaghan</a> | <a href="https://github.com/mmcgrana/gobyexample/blob/master/examples/base64-encoding">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
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</p>
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</div>
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<script>
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var codeLines = [];
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codeLines.push('');codeLines.push('package main\u000A');codeLines.push('import (\u000A b64 \"encoding/base64\"\u000A \"fmt\"\u000A)\u000A');codeLines.push('func main() {\u000A');codeLines.push(' data :\u003D \"abc123!?$*\u0026()\'-\u003D@~\"\u000A');codeLines.push(' sEnc :\u003D b64.StdEncoding.EncodeToString([]byte(data))\u000A fmt.Println(sEnc)\u000A');codeLines.push(' sDec, _ :\u003D b64.StdEncoding.DecodeString(sEnc)\u000A fmt.Println(string(sDec))\u000A fmt.Println()\u000A');codeLines.push(' uEnc :\u003D b64.URLEncoding.EncodeToString([]byte(data))\u000A fmt.Println(uEnc)\u000A uDec, _ :\u003D b64.URLEncoding.DecodeString(uEnc)\u000A fmt.Println(string(uDec))\u000A}\u000A');codeLines.push('');codeLines.push('');
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</script>
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<script src="site.js" async></script>
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</body>
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</html>
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