execute anonymous apex via ANT script

May I humbly recommend this bigass macro:

https://gist.github.com/bigassforce/af56ebda0354b273ab76

1. download the salesforce ant tool and extract it to /lib/salesforce_ant_34.0/

2. then download the missing link http library and extract it to /lib/ml-ant-http-1.1.3/

3. scaffold out your build.xml as follows, and look at the deploy target for example usage

   <project default="usage" basedir="." xmlns:sf="antlib:com.salesforce" xmlns:ml="org.missinglink.ant.task.http.HttpClientTask">
   
       <!-- Download from https://login.salesforce.com/dwnld/SfdcAnt/salesforce_ant_34.0.zip -->
       <taskdef uri="antlib:com.salesforce" classpath="lib/salesforce_ant_34.0/ant-salesforce.jar" />
   
       <!-- Download from https://code.google.com/p/missing-link/ -->
       <taskdef name="http" uri="org.missinglink.ant.task.http.HttpClientTask" classname="org.missinglink.ant.task.http.HttpClientTask" classpath="lib/ml-ant-http-1.1.3/ml-ant-http-1.1.3.jar"/>
   
       <property file="build.properties"/>
       <property environment="env"/>
   
       <target name="deploy" description="Deploys all package components to dev org">
           <!-- stop scheduled job -->
           <executeAnonymous username="${de.username}" password="${de.password}"><![CDATA[
               for (SObject j : [SELECT Id FROM CronTrigger]) System.abortJob(j.Id);
           ]]></executeAnonymous>
   
           <!-- upload code -->
           <sf:deploy
               username="${de.username}"
               password="${de.password}"
               serverurl="https://login.salesforce.com"
               deployRoot="src"
           />
   
           <!-- restart scheduled job -->
           <executeAnonymous username="${de.username}" password="${de.password}"><![CDATA[
               System.schedule('New Job', '0 0 * * * ?', new Job());
           ]]></executeAnonymous>
       </target>
   
       <macrodef name="executeAnonymous" description="Invoke ExecuteAnonymous using Salesforce Tooling API">
           <attribute name="username" description="Salesforce user name."/>
           <attribute name="password" description="Salesforce password."/>
           <text name="apexcode"/>
           <sequential>
               <!-- Login to populate serverUrl / sessionId / instance -->
               <login username="@{username}" password="@{password}" />
   
               <!-- Execute using HTTP GET -->
               <ml:http url="${instance}/services/data/v34.0/tooling/executeAnonymous" method="GET" outfile="lib/executeAnonymousResult.json"  statusProperty="loginResponseStatus">
                   <headers>
                       <header name="Authorization" value="Bearer ${sessionId}"/>
                   </headers>
                   <query>
                       <parameter name="anonymousBody" value="@{apexcode}"/>
                   </query>
               </ml:http>
   
               <!-- Fail on error -->
               <loadfile property="executeAnonymousResult" srcFile="lib/executeAnonymousResult.json" />
               <fail message="Execute Anonymous failed: ${executeAnonymousResult}">
                   <condition>
                       <resourcecontains resource="lib/executeAnonymousResult.json" substring="&quot;success&quot;:false" />
                   </condition>
               </fail>
   
               <!-- Show output -->
               <echo message="${executeAnonymousResult}" />
           </sequential>
       </macrodef>
   
       <macrodef name="login" description="Login to salesforce and populate serverUrl / sessionId / instance">
           <attribute name="username" description="Salesforce user name."/>
           <attribute name="password" description="Salesforce password."/>    
           <sequential>
               <!-- Obtain Session Id via Login SOAP service -->
               <ml:http url="https://login.salesforce.com/services/Soap/c/34.0" method="POST" failonunexpected="false" outfile="lib/loginResult.xml" statusProperty="loginResponseStatus">
                   <headers>
                       <header name="Content-Type" value="text/xml"/>
                       <header name="SOAPAction" value="login"/>
                   </headers>
                   <entity><![CDATA[
                       <env:Envelope xmlns:xsd='http://www.w3.org/2001/XMLSchema' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:env='http://schemas.xmlsoap.org/soap/envelope/'>
                           <env:Body>
                               <sf:login xmlns:sf='urn:enterprise.soap.sforce.com'>
                                   <sf:username>@{username}</sf:username>
                                   <sf:password>@{password}</sf:password>
                               </sf:login>
                           </env:Body>
                       </env:Envelope>]]>
                   </entity>
               </ml:http>
   
               <!-- Fail on error -->
               <loadfile property="loginResult" srcFile="lib/loginResult.xml" />
               <fail message="Login failed: ${loginResult}">
                   <condition>
                       <resourcecontains resource="lib/loginResult.xml" substring="faultcode" />
                   </condition>
               </fail>
   
               <!-- Parse response into properties -->
               <xmlproperty file="lib/loginResult.xml" />
               <echo file="lib/serverUrl.txt" message="${soapenv:Envelope.soapenv:Body.loginResponse.result.serverUrl}" />
               <echo file="lib/sessionId.txt" message="${soapenv:Envelope.soapenv:Body.loginResponse.result.sessionId}" />
               <echo file="lib/instance.txt" message="${soapenv:Envelope.soapenv:Body.loginResponse.result.serverUrl}" />
               <replaceregexp file="lib/instance.txt" match="(https://[^/]+)/.*" replace="\1" />
               <loadfile property="sessionId" srcFile="lib/sessionId.txt" />
               <loadfile property="instance" srcFile="lib/instance.txt" />
           </sequential>
       </macrodef>
   
   </project>
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