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<div class="section" id="middlewares">
<span id="id1"></span><h1>Middlewares<a class="headerlink" href="#middlewares" title="Permalink to this headline">¶</a></h1>
<p>Vulcand allows you to compile in middlewares that can change, intercept or reject the request or even alter the response,
and provides <code class="docutils literal"><span class="pre">vulcanbundle</span></code> command line tool to make it easy.</p>
<div class="section" id="id2">
<h2>Middlewares<a class="headerlink" href="#id2" title="Permalink to this headline">¶</a></h2>
<p>Middlewares are allowed to observe, modify and intercept http requests and responses. Each middleware is fully compatible with Go standard library <code class="docutils literal"><span class="pre">http.Handler</span></code> interface:</p>
<div class="highlight-go"><div class="highlight"><pre><span class="kd">type</span> <span class="nx">Handler</span> <span class="kd">interface</span> <span class="p">{</span>
<span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">ResponseWriter</span><span class="p">,</span> <span class="o">*</span><span class="nx">Request</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>
</div>
<ul class="simple">
<li><code class="docutils literal"><span class="pre">ServeHTTP</span></code> is called before the request is going to be forwarded to the server selected by the load balancer. This function can modify or intercept request before it gets to a final destination and change the response.</li>
</ul>
</div>
<div class="section" id="middleware-chains">
<h2>Middleware Chains<a class="headerlink" href="#middleware-chains" title="Permalink to this headline">¶</a></h2>
<p>Middleware chains define an order in which middlewares will be executed. Each Middleware handler will explicitly call next handler:</p>
<div class="highlight-go"><div class="highlight"><pre><span class="kd">func</span> <span class="p">(</span><span class="nx">h</span> <span class="o">*</span><span class="nx">MyHandler</span><span class="p">)</span> <span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">w</span> <span class="nx">http</span><span class="p">.</span><span class="nx">ResponseWriter</span><span class="p">,</span> <span class="nx">r</span> <span class="o">*</span><span class="nx">Request</span><span class="p">)</span> <span class="p">{</span>
<span class="c1">// do something with the request and pass to the next handler</span>
<span class="nx">h</span><span class="p">.</span><span class="nx">next</span><span class="p">.</span><span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="nx">r</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>
</div>
<p>In case if middleware decides to reject the request, it should not call next, and instead write it’s own response:</p>
<div class="highlight-go"><div class="highlight"><pre><span class="kd">func</span> <span class="p">(</span><span class="nx">h</span> <span class="o">*</span><span class="nx">MyHandler</span><span class="p">)</span> <span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">w</span> <span class="nx">http</span><span class="p">.</span><span class="nx">ResponseWriter</span><span class="p">,</span> <span class="nx">r</span> <span class="o">*</span><span class="nx">Request</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">io</span><span class="p">.</span><span class="nx">WriteString</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="s">"access denied"</span><span class="p">)</span>
<span class="nx">io</span><span class="p">.</span><span class="nx">WriteHeader</span><span class="p">(</span><span class="mi">403</span><span class="p">)</span>
<span class="k">return</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Example of a request that passes auth and limiting middlewares and hits the server:</p>
<div class="figure align-center">
<img alt="_images/VulcanMiddleware.png" src="_images/VulcanMiddleware.png" />
</div>
<p>Example of a request that is rejected by limiting middleware:</p>
<div class="figure align-center">
<img alt="_images/VulcanMiddlewareReject.png" src="_images/VulcanMiddlewareReject.png" />
</div>
<p>In this case server won’t process the request.</p>
</div>
<div class="section" id="vbundle">
<h2>Vbundle<a class="headerlink" href="#vbundle" title="Permalink to this headline">¶</a></h2>
<p>Vbundle is a very simple command line tool that creates a new version of vulcand daemon by writing a new <code class="docutils literal"><span class="pre">main.go</span></code> that imports the <code class="docutils literal"><span class="pre">vulcand</span></code> packages and your plugins:</p>
<div class="highlight-go"><div class="highlight"><pre><span class="kn">import</span> <span class="p">(</span>
<span class="s">"github.com/mailgun/vulcand"</span>
<span class="s">"github.com/example/extension"</span>
<span class="p">)</span>
<span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">vulcand</span><span class="p">.</span><span class="nx">RegisterPlugin</span><span class="p">(</span><span class="nx">extension</span><span class="p">.</span><span class="nx">Spec</span><span class="p">())</span>
<span class="nx">vulcand</span><span class="p">.</span><span class="nx">Run</span><span class="p">()</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Vbundle does not download anything from the internet, it just generates the program for you. To compile, the packages and dependencies should be in your working environment.</p>
<div class="section" id="example-auth-middleware">
<h3>Example - Auth middleware<a class="headerlink" href="#example-auth-middleware" title="Permalink to this headline">¶</a></h3>
<p>In this example, we will write a new fully functional (but insecure) middleware that will require all requests to be authorized with HTTP basic auth.
For this demo, we’ve created <code class="docutils literal"><span class="pre">auth</span></code> package in our environment. Full source code is available at: <a class="reference external" href="http://github.com/mailgun/vulcand-auth">http://github.com/mailgun/vulcand-auth</a></p>
<div class="section" id="describing-your-middleware">
<h4>Describing your middleware<a class="headerlink" href="#describing-your-middleware" title="Permalink to this headline">¶</a></h4>
<p>Vulcand looks for a special function <code class="docutils literal"><span class="pre">GetSpec</span></code> that returns all that it needs to know about this middleware.</p>
<div class="highlight-go"><div class="highlight"><pre><span class="kn">import</span> <span class="p">(</span>
<span class="s">"github.com/mailgun/vulcand/plugin"</span>
<span class="p">)</span>
<span class="kd">const</span> <span class="nx">Type</span> <span class="p">=</span> <span class="s">"auth"</span>
<span class="kd">func</span> <span class="nx">GetSpec</span><span class="p">()</span> <span class="o">*</span><span class="nx">plugin</span><span class="p">.</span><span class="nx">MiddlewareSpec</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">&</span><span class="nx">plugin</span><span class="p">.</span><span class="nx">MiddlewareSpec</span><span class="p">{</span>
<span class="nx">Type</span><span class="p">:</span> <span class="nx">Type</span><span class="p">,</span> <span class="c1">// A short name for the middleware</span>
<span class="nx">FromOther</span><span class="p">:</span> <span class="nx">FromOther</span><span class="p">,</span> <span class="c1">// Tells vulcand how to create middleware from another one</span>
<span class="nx">FromCli</span><span class="p">:</span> <span class="nx">FromCli</span><span class="p">,</span> <span class="c1">// Tells vulcand how to create middleware from CLI</span>
<span class="nx">CliFlags</span><span class="p">:</span> <span class="nx">CliFlags</span><span class="p">(),</span> <span class="c1">// Vulcand will add this flags CLI command</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
<p>We will get back to each one of this functions later, for now let’s create a middleware struct itself.
Our Auth plugin is a struct that stores username and password.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Your struct should contain only values expected in: <a class="reference external" href="http://golang.org/pkg/encoding/json/#Marshal">http://golang.org/pkg/encoding/json/#Marshal</a></p>
</div>
<div class="highlight-go"><div class="highlight"><pre><span class="c1">// AuthMiddleware struct holds configuration parameters and is used to</span>
<span class="c1">// serialize/deserialize the configuration from storage engines.</span>
<span class="kd">type</span> <span class="nx">AuthMiddleware</span> <span class="kd">struct</span> <span class="p">{</span>
<span class="nx">Password</span> <span class="kt">string</span>
<span class="nx">Username</span> <span class="kt">string</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="handler">
<h4>Handler<a class="headerlink" href="#handler" title="Permalink to this headline">¶</a></h4>
<p>Let’s define <code class="docutils literal"><span class="pre">ServeHTTP</span></code> handler that will be called on each request and response.</p>
<div class="highlight-go"><div class="highlight"><pre> <span class="c1">// Auth middleware handler</span>
<span class="kd">type</span> <span class="nx">AuthHandler</span> <span class="kd">struct</span> <span class="p">{</span>
<span class="nx">cfg</span> <span class="nx">AuthMiddleware</span>
<span class="nx">next</span> <span class="nx">http</span><span class="p">.</span><span class="nx">Handler</span>
<span class="p">}</span>
<span class="c1">// This function will be called each time the request hits the location with this middleware activated</span>
<span class="kd">func</span> <span class="p">(</span><span class="nx">a</span> <span class="o">*</span><span class="nx">AuthHandler</span><span class="p">)</span> <span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">w</span> <span class="nx">http</span><span class="p">.</span><span class="nx">ResponseWriter</span><span class="p">,</span> <span class="nx">r</span> <span class="o">*</span><span class="nx">http</span><span class="p">.</span><span class="nx">Request</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">auth</span><span class="p">,</span> <span class="nx">err</span> <span class="o">:=</span> <span class="nx">utils</span><span class="p">.</span><span class="nx">ParseAuthHeader</span><span class="p">(</span><span class="nx">r</span><span class="p">.</span><span class="nx">Header</span><span class="p">.</span><span class="nx">Get</span><span class="p">(</span><span class="s">"Authorization"</span><span class="p">))</span>
<span class="c1">// Reject the request by writing forbidden response</span>
<span class="k">if</span> <span class="nx">err</span> <span class="o">!=</span> <span class="kc">nil</span> <span class="o">||</span> <span class="nx">a</span><span class="p">.</span><span class="nx">cfg</span><span class="p">.</span><span class="nx">Username</span> <span class="o">!=</span> <span class="nx">auth</span><span class="p">.</span><span class="nx">Username</span> <span class="o">||</span> <span class="nx">a</span><span class="p">.</span><span class="nx">cfg</span><span class="p">.</span><span class="nx">Password</span> <span class="o">!=</span> <span class="nx">auth</span><span class="p">.</span><span class="nx">Password</span> <span class="p">{</span>
<span class="nx">w</span><span class="p">.</span><span class="nx">WriteHeader</span><span class="p">(</span><span class="nx">http</span><span class="p">.</span><span class="nx">StatusForbidden</span><span class="p">)</span>
<span class="nx">io</span><span class="p">.</span><span class="nx">WriteString</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="s">"Forbidden"</span><span class="p">)</span>
<span class="k">return</span>
<span class="p">}</span>
<span class="c1">// Pass the request to the next middleware in chain</span>
<span class="nx">a</span><span class="p">.</span><span class="nx">next</span><span class="p">.</span><span class="nx">ServeHTTP</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="nx">r</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">it is important to call next handler if you want to pass the request to the server</p>
</div>
<p>As you may noticed, <code class="docutils literal"><span class="pre">AuthHandler</span></code> is fully compatible with <code class="docutils literal"><span class="pre">http.Handler</span></code>. This is very handy as you may now re-use all these middlewares available in the internet, like this one:</p>
<ul class="simple">
<li><a class="reference external" href="https://github.com/codahale/http-handlers">https://github.com/codahale/http-handlers</a></li>
<li><a class="reference external" href="https://github.com/mailgun/oxy">https://github.com/mailgun/oxy</a></li>
</ul>
</div>
<div class="section" id="utility-functions">
<h4>Utility functions<a class="headerlink" href="#utility-functions" title="Permalink to this headline">¶</a></h4>
<p>Let’s define some other important functions as the next step.</p>
<div class="highlight-go"><div class="highlight"><pre><span class="c1">// This function is optional but handy, used to check input parameters when creating new middlewares</span>
<span class="kd">func</span> <span class="nx">New</span><span class="p">(</span><span class="nx">user</span><span class="p">,</span> <span class="nx">pass</span> <span class="kt">string</span><span class="p">)</span> <span class="p">(</span><span class="o">*</span><span class="nx">AuthMiddleware</span><span class="p">,</span> <span class="kt">error</span><span class="p">)</span> <span class="p">{</span>
<span class="k">if</span> <span class="nx">user</span> <span class="o">==</span> <span class="s">""</span> <span class="o">||</span> <span class="nx">pass</span> <span class="o">==</span> <span class="s">""</span> <span class="p">{</span>
<span class="k">return</span> <span class="kc">nil</span><span class="p">,</span> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Errorf</span><span class="p">(</span><span class="s">"Username and password can not be empty"</span><span class="p">)</span>
<span class="p">}</span>
<span class="k">return</span> <span class="o">&</span><span class="nx">AuthMiddleware</span><span class="p">{</span><span class="nx">Username</span><span class="p">:</span> <span class="nx">user</span><span class="p">,</span> <span class="nx">Password</span><span class="p">:</span> <span class="nx">pass</span><span class="p">},</span> <span class="kc">nil</span>
<span class="p">}</span>
<span class="c1">// This function is important, it's called by vulcand to create a new handler from the middleware config and put it into the</span>
<span class="c1">// middleware chain. Note that we need to remember 'next' handler to call</span>
<span class="kd">func</span> <span class="p">(</span><span class="nx">c</span> <span class="o">*</span><span class="nx">AuthMiddleware</span><span class="p">)</span> <span class="nx">NewHandler</span><span class="p">(</span><span class="nx">next</span> <span class="nx">http</span><span class="p">.</span><span class="nx">Handler</span><span class="p">)</span> <span class="p">(</span><span class="nx">http</span><span class="p">.</span><span class="nx">Handler</span><span class="p">,</span> <span class="kt">error</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="o">&</span><span class="nx">AuthHandler</span><span class="p">{</span><span class="nx">next</span><span class="p">:</span> <span class="nx">next</span><span class="p">,</span> <span class="nx">cfg</span><span class="p">:</span> <span class="o">*</span><span class="nx">c</span><span class="p">},</span> <span class="kc">nil</span>
<span class="p">}</span>
<span class="c1">// String() will be called by loggers inside Vulcand and command line tool.</span>
<span class="kd">func</span> <span class="p">(</span><span class="nx">c</span> <span class="o">*</span><span class="nx">AuthMiddleware</span><span class="p">)</span> <span class="nx">String</span><span class="p">()</span> <span class="kt">string</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Sprintf</span><span class="p">(</span><span class="s">"username=%v, pass=%v"</span><span class="p">,</span> <span class="nx">c</span><span class="p">.</span><span class="nx">Username</span><span class="p">,</span> <span class="s">"********"</span><span class="p">)</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="constructors">
<h4>Constructors<a class="headerlink" href="#constructors" title="Permalink to this headline">¶</a></h4>
<p>As the final step, lets define the functions required by <code class="docutils literal"><span class="pre">GetSpec</span></code>, these ones will be called by <code class="docutils literal"><span class="pre">Vulcand</span></code> when it will need to
create new auth middlewares:</p>
<div class="highlight-go"><div class="highlight"><pre><span class="c1">// FromOther Will be called by Vulcand when engine or API will read the middleware from the serialized format.</span>
<span class="c1">// It's important that the signature of the function will be exactly the same, otherwise Vulcand will</span>
<span class="c1">// fail to register this middleware.</span>
<span class="c1">// The first and the only parameter should be the struct itself, no pointers and other variables.</span>
<span class="c1">// Function should return middleware interface and error in case if the parameters are wrong.</span>
<span class="kd">func</span> <span class="nx">FromOther</span><span class="p">(</span><span class="nx">c</span> <span class="nx">AuthMiddleware</span><span class="p">)</span> <span class="p">(</span><span class="nx">plugin</span><span class="p">.</span><span class="nx">Middleware</span><span class="p">,</span> <span class="kt">error</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">New</span><span class="p">(</span><span class="nx">c</span><span class="p">.</span><span class="nx">Username</span><span class="p">,</span> <span class="nx">c</span><span class="p">.</span><span class="nx">Password</span><span class="p">)</span>
<span class="p">}</span>
<span class="c1">// FromCli constructs the middleware from the command line</span>
<span class="kd">func</span> <span class="nx">FromCli</span><span class="p">(</span><span class="nx">c</span> <span class="o">*</span><span class="nx">cli</span><span class="p">.</span><span class="nx">Context</span><span class="p">)</span> <span class="p">(</span><span class="nx">plugin</span><span class="p">.</span><span class="nx">Middleware</span><span class="p">,</span> <span class="kt">error</span><span class="p">)</span> <span class="p">{</span>
<span class="k">return</span> <span class="nx">New</span><span class="p">(</span><span class="nx">c</span><span class="p">.</span><span class="nx">String</span><span class="p">(</span><span class="s">"user"</span><span class="p">),</span> <span class="nx">c</span><span class="p">.</span><span class="nx">String</span><span class="p">(</span><span class="s">"pass"</span><span class="p">))</span>
<span class="p">}</span>
<span class="c1">// CliFlags will be used by Vulcand construct help and CLI command for the vctl command</span>
<span class="kd">func</span> <span class="nx">CliFlags</span><span class="p">()</span> <span class="p">[]</span><span class="nx">cli</span><span class="p">.</span><span class="nx">Flag</span> <span class="p">{</span>
<span class="k">return</span> <span class="p">[]</span><span class="nx">cli</span><span class="p">.</span><span class="nx">Flag</span><span class="p">{</span>
<span class="nx">cli</span><span class="p">.</span><span class="nx">StringFlag</span><span class="p">{</span><span class="s">"user, u"</span><span class="p">,</span> <span class="s">""</span><span class="p">,</span> <span class="s">"Basic auth username"</span><span class="p">,</span> <span class="s">""</span><span class="p">},</span>
<span class="nx">cli</span><span class="p">.</span><span class="nx">StringFlag</span><span class="p">{</span><span class="s">"pass, p"</span><span class="p">,</span> <span class="s">""</span><span class="p">,</span> <span class="s">"Basic auth pass"</span><span class="p">,</span> <span class="s">""</span><span class="p">},</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="imports">
<h4>Imports<a class="headerlink" href="#imports" title="Permalink to this headline">¶</a></h4>
<p>Let’s take a look at all imports used in the <a class="reference external" href="http://github.com/mailgun/vulcand-auth">http://github.com/mailgun/vulcand-auth</a></p>
<div class="highlight-go"><div class="highlight"><pre><span class="c1">// Note that I import the versions bundled with vulcand. That will make our lives easier, as we'll use exactly the same versions used</span>
<span class="c1">// by vulcand. We are escaping dependency management troubles thanks to Godep.</span>
<span class="kn">import</span> <span class="p">(</span>
<span class="s">"fmt"</span>
<span class="s">"io"</span>
<span class="s">"net/http"</span>
<span class="s">"github.com/mailgun/vulcand/Godeps/_workspace/src/github.com/codegangsta/cli"</span>
<span class="s">"github.com/mailgun/vulcand/Godeps/_workspace/src/github.com/mailgun/oxy/utils"</span>
<span class="s">"github.com/mailgun/vulcand/plugin"</span>
<span class="p">)</span>
</pre></div>
</div>
<p>Vulcand uses <a class="reference external" href="https://github.com/tools/godep">Godep</a> to manage it dependencies, we encourage you to read it’s docs.
That’s why all imports to shared libraries are pointing to versions vendored with the version of vulcand you are using.</p>
</div>
<div class="section" id="getting-it-together">
<h4>Getting it together<a class="headerlink" href="#getting-it-together" title="Permalink to this headline">¶</a></h4>
<p>Let’s create a folder in <code class="docutils literal"><span class="pre">GOPATH</span></code> environment that will be used for your version of <code class="docutils literal"><span class="pre">Vulcand</span></code> compiled with the new middleware.
In our case it looks like this:</p>
<div class="highlight-bash"><div class="highlight"><pre>/home/alex/goworld/src/github.com/mailgun/vulcand-bundle
</pre></div>
</div>
<p>In your case it would be something different. Now execute the vbundle command, you should see something like this:</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="nv">$ </span>vbundle init --middleware<span class="o">=</span>github.com/mailgun/vulcand-auth/auth
Dec <span class="m">26</span> 01:02:57.180: INFO PID:16442 <span class="o">[</span>main.go:51<span class="o">]</span> SUCCESS: bundle vulcand and vctl completed
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last"><code class="docutils literal"><span class="pre">--middleware=github.com/mailgun/vulcand-auth/auth</span></code> flag tells the tool to include our auth middleware into bundle.</p>
</div>
<p>Let us check that it actually did something:</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="nv">$ </span>ls
main.go registry vctl
</pre></div>
</div>
<p>What just happened? Vbundle wrote a new version of <code class="docutils literal"><span class="pre">main.go</span></code> and <code class="docutils literal"><span class="pre">vctl</span></code> that have our <code class="docutils literal"><span class="pre">auth</span></code> middleware plugged in.
The final step would be to install the bundle. Let’s <code class="docutils literal"><span class="pre">cd</span></code> to the vulcand-bundle dir and execute the build commands</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="nv">$ </span>go build -o vulcand
<span class="nv">$ </span><span class="nb">pushd </span>vctl/ <span class="o">&&</span> go build -o vctl <span class="o">&&</span> <span class="nb">popd</span>
</pre></div>
</div>
<p>Congrats! Now you have your version of <code class="docutils literal"><span class="pre">vulcand</span></code> and <code class="docutils literal"><span class="pre">vctl</span></code> Let’s use it and try a couple of tricks with the new middleware
to ensure it actually works.</p>
<p>We need to start the new binary and configure the server first. (If you have it configured, just skip configuration steps below)</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="c"># start the daemon</span>
<span class="nv">$ </span>./vulcand -etcd http://localhost:4001
<span class="c"># add host, location and upstream with endpoints via newly compiled command line tool</span>
<span class="nv">$ </span>./vctl/vctl backend upsert -id b1
<span class="nv">$ </span>./vctl/vctl server upsert -id srv1 -b b1 -url http://localhost:5000
<span class="nv">$ </span>./vctl/vctl frontend upsert -id f1 -b b1 -route <span class="s1">'Path("/")'</span>
</pre></div>
</div>
</div>
<div class="section" id="using-auth-middleware">
<h4>Using Auth middleware<a class="headerlink" href="#using-auth-middleware" title="Permalink to this headline">¶</a></h4>
<p>Now to the fun part, you can configure the new authorization. Make sure that auth command is now available:</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="nv">$ </span>./vctl/vctl auth --help
<span class="nv">$ </span>./vctl/vctl auth upsert --help
</pre></div>
</div>
<p>Let’s play with the new feature!</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="c"># add the auth</span>
<span class="nv">$ </span>./vctl/vctl auth upsert -f f1 -user<span class="o">=</span>hello -pass<span class="o">=</span>world
OK: auth upserted
<span class="c"># try it out</span>
<span class="nv">$ </span>curl http://localhost:8181/
Forbidden
<span class="c"># ok, here you go:</span>
<span class="nv">$ </span>curl -u hello:world http://localhost:8181/
ok
</pre></div>
</div>
</div>
<div class="section" id="etcd">
<h4>Etcd<a class="headerlink" href="#etcd" title="Permalink to this headline">¶</a></h4>
<p>Note that you can use Etcd to configure the new middleware, <code class="docutils literal"><span class="pre">vulcand</span></code> will load it from json representation:</p>
<div class="highlight-bash"><div class="highlight"><pre><span class="nv">$ </span>etcdctl <span class="nb">set</span> /vulcand/frontends/f1/middlewares/auth1 <span class="s1">'{"Type": "auth", "Middleware":{"Username": "user", "Password": "secret1"}}'</span>
</pre></div>
</div>
</div>
<div class="section" id="testing">
<h4>Testing<a class="headerlink" href="#testing" title="Permalink to this headline">¶</a></h4>
<p>We were in a hurry trying to get it all working, didn’t we? Now we can step back and cover it all by tests:</p>
<p><a class="reference external" href="https://github.com/mailgun/vulcand-auth/blob/master/auth/auth_test.go">https://github.com/mailgun/vulcand-auth/blob/master/auth/auth_test.go</a></p>
</div>
<div class="section" id="maintenance">
<h4>Maintenance<a class="headerlink" href="#maintenance" title="Permalink to this headline">¶</a></h4>
<p>Note that vbundle simply writes the new <code class="docutils literal"><span class="pre">vulcanbundle</span></code> for you, and does not try to get in your way of managing your environment.
However, here are a couple of tips if you feel like you need ones:</p>
<ul class="simple">
<li>Your new bundle is just a go program like any other one out there.</li>
<li>This means that you can add it to your repo, and update periodically by calling <code class="docutils literal"><span class="pre">vbundle</span> <span class="pre">init</span></code> with new parameters.</li>
<li>You can use <code class="docutils literal"><span class="pre">godep</span> <span class="pre">save</span> <span class="pre">-r</span> <span class="pre">./...</span></code> with new bundle as well to make sure your bundle’s deps are always there.</li>
</ul>
</div>
</div>
</div>
</div>
</div>
</div>
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<p><a href="https://github.com/mailgun/vulcand">Found a typo? Send a pull request!</a></p>
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