diff --git a/.travis.yml b/.travis.yml
index 986569e..467c92b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,6 +19,8 @@ matrix:
     - php: 7.1
       env: DB=PGSQL RECIPE_VERSION=4.2.x-dev PHPUNIT_COVERAGE_TEST=1
     - php: 7.2
+      env: DB=MYSQL RECIPE_VERSION=4.3.x-dev PHPUNIT_TEST=1
+    - php: 7.3
       env: DB=MYSQL RECIPE_VERSION=4.x-dev PHPUNIT_TEST=1
 
 before_script:
@@ -34,7 +36,7 @@ before_script:
 
   # Install composer dependencies
   - composer validate
-  - composer require --no-update silverstripe/recipe-core "$RECIPE_VERSION"
+  - composer require --no-update silverstripe/recipe-cms:"$RECIPE_VERSION"
   - if [[ $DB == PGSQL ]]; then composer require --no-update silverstripe/postgresql 2.1.x-dev; fi
   - composer install --prefer-dist --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
 
diff --git a/composer.json b/composer.json
index 5bc6bda..a867690 100644
--- a/composer.json
+++ b/composer.json
@@ -29,6 +29,12 @@
         "squizlabs/php_codesniffer": "^3",
         "phpunit/phpunit": "^5.7"
     },
+    "autoload": {
+        "psr-4": {
+            "SilverStripe\\TextExtraction\\": "src/",
+            "SilverStripe\\TextExtraction\\Tests\\": "tests/"
+        }
+    },
     "suggest": {
         "ext-fileinfo": "Improved support for file mime detection"
     },
diff --git a/src/Extractor/TikaServerTextExtractor.php b/src/Extractor/TikaServerTextExtractor.php
index eb9be4b..be96e0d 100644
--- a/src/Extractor/TikaServerTextExtractor.php
+++ b/src/Extractor/TikaServerTextExtractor.php
@@ -86,7 +86,7 @@ class TikaServerTextExtractor extends FileTextExtractor
     {
         return $this->getServerEndpoint()
             && $this->getClient()->isAvailable()
-            && version_compare($this->getVersion(), '1.7.0') >= 0;
+            && version_compare($this->getVersion(), '1.7') >= 0;
     }
 
     /**
diff --git a/src/Rest/TikaRestClient.php b/src/Rest/TikaRestClient.php
index 2a109a8..1ed762a 100644
--- a/src/Rest/TikaRestClient.php
+++ b/src/Rest/TikaRestClient.php
@@ -149,7 +149,7 @@ class TikaRestClient extends Client
             Injector::inst()->get(LoggerInterface::class)->info($msg);
         }
 
-        return $text;
+        return (string) $text;
     }
 
     /**
diff --git a/tests/TikaServerTextExtractorTest.php b/tests/TikaServerTextExtractorTest.php
index 0d9a7ed..2239499 100644
--- a/tests/TikaServerTextExtractorTest.php
+++ b/tests/TikaServerTextExtractorTest.php
@@ -2,9 +2,11 @@
 
 namespace SilverStripe\TextExtraction\Tests;
 
+use PHPUnit_Framework_MockObject_MockObject;
 use SilverStripe\Assets\File;
 use SilverStripe\Dev\SapphireTest;
 use SilverStripe\TextExtraction\Extractor\TikaServerTextExtractor;
+use SilverStripe\TextExtraction\Rest\TikaRestClient;
 
 /**
  * @group tika-tests
@@ -33,4 +35,44 @@ class TikaServerTextExtractorTest extends SapphireTest
         $this->assertTrue($extractor->supportsMime('text/html'));
         $this->assertFalse($extractor->supportsMime('application/not-supported'));
     }
+
+    /**
+     * @param string $version
+     * @param bool $expected
+     * @dataProvider isAvailableProvider
+     */
+    public function testIsAvailable($version, $expected)
+    {
+        /** @var PHPUnit_Framework_MockObject_MockObject|TikaServerTextExtractor $extractor */
+        $extractor = $this->getMockBuilder(TikaServerTextExtractor::class)
+            ->setMethods(['getClient', 'getServerEndpoint'])
+            ->getMock();
+
+        $client = $this->createMock(TikaRestClient::class);
+        $client->method('isAvailable')->willReturn(true);
+        $client->method('getVersion')->willReturn($version);
+
+        $extractor->method('getClient')->willReturn($client);
+        $extractor->method('getServerEndpoint')->willReturn('tikaserver.example');
+
+        $result = $extractor->isAvailable();
+        $this->assertSame($expected, $result);
+    }
+
+    /**
+     * @return array[]
+     */
+    public function isAvailableProvider()
+    {
+        return [
+            ['1.5.2', false],
+            ['1.5', false],
+            ['1.7.0', true],
+            ['1.7.5', true],
+            ['1.8.0', true],
+            ['1.7', true],
+            ['1.8', true],
+            ['2.0.0', true],
+        ];
+    }
 }