How to pull all available query fields for an SOQL object? - salesforce

Question

So, I'm seeing Stackoverflow is more responsive than the actual Salesforce community and I'm reposting my question from here:
How can I pull a list of all of the available query fields for an SOQL object? I have my DataLoader script ready to go, but I need a way to pull all the query fields for specific SOQL data objects and feed them into my process-conf.xml file in DataLoader to pull the values of all those fields to a separate location. I have the DataLoader value pulling already setup, but I need a way to get all the available query fields as they continue to change. The ANT Migration Tool does not appear to be able to pull the query fields itself.
ANT Tool configuration:
# build.properties
# Specify the login credentials for the desired Salesforce organization
sf.username = <test user acct>
sf.password = <password>
#sf.sessionId = <Insert your Salesforce session id here. Use this or username/password above. Cannot use both>
#sf.pkgName = <Insert comma separated package names to be retrieved>
#sf.zipFile = <Insert path of the zipfile to be retrieved>
#sf.metadataType = <Insert metadata type name for which listMetadata or bulkRetrieve operations are to be performed>
sf.serverurl = https://na3.salesforce.com
sf.maxPoll = 20
# If your network requires an HTTP proxy, see http://ant.apache.org/manual/proxy.html for configuration.
#
logType=Detail
build.xml
<project name="Sample usage of Salesforce Ant tasks" default="test" basedir="." xmlns:sf="antlib:com.salesforce">
<property file="build.properties"/>
<property environment="env"/>
<!-- Setting default value for username, password and session id properties to empty string
so unset values are treated as empty. Without this, ant expressions such as ${sf.username}
will be treated literally.
-->
<condition property="sf.username" value=""> <not> <isset property="sf.username"/> </not> </condition>
<condition property="sf.password" value=""> <not> <isset property="sf.password"/> </not> </condition>
<condition property="sf.sessionId" value=""> <not> <isset property="sf.sessionId"/> </not> </condition>
<taskdef resource="com/salesforce/antlib.xml" uri="antlib:com.salesforce">
<classpath>
<pathelement location="ant-salesforce.jar" />
</classpath>
</taskdef>
<!-- See what happens here -->
<target name="retrieveSOQL">
<sf:retrieve
username="${sf.username}"
password="${sf.password}"
sessionId="${sf.sessionId}"
serverurl="${sf.serverurl}"
retrieveTarget="output"
unpackaged="package.xml"/>
</target>
</project>
Package.xml
<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
<types>
<members>Account</members>
<members>Opportunity</members>
<members>Lead</members>
<members>Event</members>
<members>Project__c</members>
<name>CustomObject</name>
</types>
<version>41.0</version>
</Package>
process-conf.xml
<beans>
<bean id="AccountExtract"
class="com.salesforce.dataloader.process.ProcessRunner"
singleton="false">
<description>csvAccountExtract job</description>
<property name="name" value="csvAccountExtract"/>
<property name="configOverrideMap">
<map>
<entry key="sfdc.debugMessages" value="false"/>
<entry key="sfdc.debugMessagesFile" value="C:\Users\user\Desktop\salesforce_backup\sfdcSoapTrace.log"/>
<entry key="sfdc.endpoint" value="https://na3.salesforce.com"/>
<entry key="sfdc.username" value="<username>"/>
<!-- password below has been encrypted using key file, therefore it will not work without the key setting: process.encryptionKeyFile
the password is not a valid encrypted value, please generate the real value using encrypt.bat utility -->
<entry key="sfdc.password" value="<password>"/>
<entry key="process.encryptionKeyFile" value="key.txt"/>
<entry key="sfdc.timeoutSecs" value="600"/>
<entry key="sfdc.loadBatchSize" value="200"/>
<entry key="sfdc.entity" value="Account"/>
<entry key="sfdc.extractionRequestSize" value="500"/>
<entry key="sfdc.extractionSOQL" value="Select Id, IsDeleted, MasterRecordId, Name, Type, RecordTypeId, ParentId, BillingStreet FROM Account"/>
<entry key="process.operation" value="extract"/>
<entry key="dataAccess.type" value="csvWrite"/>
<entry key="dataAccess.name" value="C:\Users\user\Desktop\account.csv"/>
</map>
</property>
</bean>
...
</beans>