Configuration from file or environment variables

build.gradle

@@ -32,6 +32,7 @@ dependencies {
     testImplementation 'commons-io:commons-io:2.11.0'
     testImplementation 'org.mockito:mockito-core:4.4.0'
     testImplementation 'com.squareup.okhttp3:mockwebserver:4.9.3'
+    testImplementation 'uk.org.webcompere:system-stubs-testng:2.1.3'
 }
 
 test {

src/main/java/io/visual_regression_tracker/sdk_java/VisualRegressionTracker.java

@@ -7,6 +7,7 @@
 import io.visual_regression_tracker.sdk_java.response.TestRunResponse;
 import lombok.extern.slf4j.Slf4j;
 
+import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.net.http.HttpClient;
@@ -24,6 +25,7 @@ enum METHOD {
 public class VisualRegressionTracker {
 
     private static final String TRACKER_NOT_STARTED = "Visual Regression Tracker has not been started";
+    private static final String CONFIG_FILE_NAME = "vrt.json";
     protected static final String API_KEY_HEADER = "apiKey";
     protected static final String PROJECT_HEADER = "project";
     protected Gson gson;
@@ -32,6 +34,17 @@ public class VisualRegressionTracker {
     protected String buildId;
     protected String projectId;
 
+    public VisualRegressionTracker() {
+        VisualRegressionTrackerConfig.VisualRegressionTrackerConfigBuilder configBuilder = VisualRegressionTrackerConfig.builder();
+        File configFile = new File(CONFIG_FILE_NAME);
+        if (configFile.exists()) {
+            configBuilder.configFile(configFile);
+        }
+        configuration = configBuilder.build();
+        paths = new PathProvider(configuration.getApiUrl());
+        gson = new Gson();
+    }
+
     public VisualRegressionTracker(VisualRegressionTrackerConfig trackerConfig) {
         configuration = trackerConfig;
         paths = new PathProvider(trackerConfig.getApiUrl());

src/main/java/io/visual_regression_tracker/sdk_java/VisualRegressionTrackerConfig.java

@@ -1,15 +1,26 @@
 package io.visual_regression_tracker.sdk_java;
 
-import lombok.AllArgsConstructor;
-import lombok.Builder;
-import lombok.Data;
-import lombok.NonNull;
-import lombok.RequiredArgsConstructor;
-
-@Data
-@Builder
+import com.google.gson.Gson;
+import com.google.gson.reflect.TypeToken;
+import lombok.*;
+import lombok.experimental.Accessors;
+import lombok.extern.slf4j.Slf4j;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.Field;
+import java.lang.reflect.Type;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.Collections;
+import java.util.Map;
+import java.util.function.Function;
+
+@Data()
 @RequiredArgsConstructor
 @AllArgsConstructor
+@Accessors(chain = true)
+@Slf4j
 public class VisualRegressionTrackerConfig {
 
     @NonNull
@@ -18,12 +29,145 @@ public class VisualRegressionTrackerConfig {
     private final String apiKey;
     @NonNull
     private final String project;
-    @Builder.Default
-    private String branchName = null;
-    @Builder.Default
-    private String ciBuildId = null;
-    @Builder.Default
-    private Boolean enableSoftAssert = false;
-    @Builder.Default
-    private int httpTimeoutInSeconds = 10;
+
+    private String branchName;
+    private String ciBuildId;
+    private Boolean enableSoftAssert;
+    private int httpTimeoutInSeconds;
+
+    public static VisualRegressionTrackerConfigBuilder builder() {
+        return new VisualRegressionTrackerConfigBuilder();
+    }
+
+    public static class VisualRegressionTrackerConfigBuilder {
+        private String apiUrl;
+        private String apiKey;
+        private String project;
+
+        private String branchName;
+        private String ciBuildId;
+        private Boolean enableSoftAssert;
+        private Integer httpTimeoutInSeconds;
+
+        private File configFile;
+
+        private static final String VRT_ENV_VARIABLE_PREFIX = "VRT_";
+        private static final boolean DEFAULT_SOFT_ASSERTION_STATE = false;
+        private static final int DEFAULT_HTTP_TIMEOUT_SECONDS = 10;
+
+        public VisualRegressionTrackerConfigBuilder apiUrl(String apiUrl) {
+            this.apiUrl = apiUrl;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder apiKey(String apiKey) {
+            this.apiKey = apiKey;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder project(String project) {
+            this.project = project;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder branchName(String branchName) {
+            this.branchName = branchName;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder ciBuildId(String ciBuildId) {
+            this.ciBuildId = ciBuildId;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder enableSoftAssert(Boolean enableSoftAssert) {
+            this.enableSoftAssert = enableSoftAssert;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder httpTimeoutInSeconds(int httpTimeoutInSeconds) {
+            this.httpTimeoutInSeconds = httpTimeoutInSeconds;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfigBuilder configFile(File configFile) {
+            this.configFile = configFile;
+            return this;
+        }
+
+        public VisualRegressionTrackerConfig build() {
+            Map<String, Object> configFromFile = Collections.emptyMap();
+            if (configFile != null) {
+                configFromFile = readConfigFromFile(configFile);
+            }
+
+            String actualApiUrl = resolve("apiUrl", configFromFile);
+            String actualApiKey = resolve("apiKey", configFromFile);
+            String actualProject = resolve("project", configFromFile);
+
+            VisualRegressionTrackerConfig config = new VisualRegressionTrackerConfig(actualApiUrl, actualApiKey, actualProject);
+            config.setCiBuildId(resolve("ciBuildId", configFromFile));
+            config.setBranchName(resolve("branchName", configFromFile));
+
+            Boolean actualEnableSoftAssert = resolve("enableSoftAssert", configFromFile);
+            config.setEnableSoftAssert(actualEnableSoftAssert == null ? DEFAULT_SOFT_ASSERTION_STATE : actualEnableSoftAssert);
+
+            Integer actualHttpTimeoutInSeconds = resolve("httpTimeoutInSeconds", configFromFile);
+            config.setHttpTimeoutInSeconds(actualHttpTimeoutInSeconds == null ? DEFAULT_HTTP_TIMEOUT_SECONDS : actualHttpTimeoutInSeconds);
+
+            return config;
+        }
+
+        private Map<String, Object> readConfigFromFile(File configFile) {
+            if (!configFile.exists()) {
+                throw new IllegalArgumentException("File " + configFile + " doesn't exist");
+            }
+
+            String fileContent;
+            try {
+                fileContent = Files.readString(configFile.toPath(), StandardCharsets.UTF_8);
+            } catch (IOException e) {
+                throw new IllegalArgumentException("Can't read content of provided config file", e);
+            }
+            Type mapType = new TypeToken<Map<String, Object>>() {}.getType();
+            return new Gson().fromJson(fileContent, mapType);
+        }
+
+        @SneakyThrows
+        private <T> T resolve(String propertyName, Map<String, Object> configurationFromFile) {
+            // 1. check if it was initialized explicitly in builder
+            // 2. check if env variable exists
+            // 3. try to read from file as last resort
+            Field field = this.getClass().getDeclaredField(propertyName);
+            Object propertyValue = field.get(this);
+            if (propertyValue != null) {
+                return (T) propertyValue;
+            }
+
+            String environmentVariableName = VRT_ENV_VARIABLE_PREFIX +  propertyName.toUpperCase();
+            propertyValue = System.getenv(environmentVariableName);
+            if (propertyValue != null) {
+                log.debug("Value of '{}' resolved from environment variable {}", propertyName, environmentVariableName);
+                Function<String, ?> parser = findParser(field.getType());
+                return (T) parser.apply((String)propertyValue);
+            }
+
+            propertyValue = configurationFromFile.get(propertyName);
+            if (propertyValue != null) {
+                log.debug("Value of '{}' resolved from config file", propertyName);
+            }
+            return propertyValue == null ? null : (T) propertyValue;
+        }
+
+        private Function<String, ?> findParser(Class<?> cls) {
+            if (cls.equals(Boolean.class)) {
+                return Boolean::parseBoolean;
+            }
+            if (cls.equals(Integer.class)) {
+                return Integer::parseInt;
+            }
+            return String::valueOf;
+        }
+    }
+
 }

src/test/java/io/visual_regression_tracker/sdk_java/VisualRegressionTrackerConfigTest.java

@@ -0,0 +1,114 @@
+package io.visual_regression_tracker.sdk_java;
+
+import org.testng.annotations.Test;
+import uk.org.webcompere.systemstubs.environment.EnvironmentVariables;
+
+import java.io.File;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class VisualRegressionTrackerConfigTest {
+
+    @Test(expectedExceptions = NullPointerException.class,
+            expectedExceptionsMessageRegExp = "apiKey is marked non-null but is null")
+    public void shouldThrowExceptionIfApiKeyMissed() {
+        VisualRegressionTrackerConfig
+                .builder()
+                .apiUrl("")
+                .project("")
+                .build();
+    }
+
+    @Test(expectedExceptions = NullPointerException.class,
+            expectedExceptionsMessageRegExp = "apiUrl is marked non-null but is null")
+    public void shouldThrowExceptionIfApiUrlMissed() {
+        VisualRegressionTrackerConfig
+                .builder()
+                .apiKey("")
+                .project("")
+                .build();
+    }
+
+    @Test(expectedExceptions = NullPointerException.class,
+            expectedExceptionsMessageRegExp = "project is marked non-null but is null")
+    public void shouldThrowExceptionIfProjectMissed() {
+        VisualRegressionTrackerConfig
+                .builder()
+                .apiKey("")
+                .apiUrl("")
+                .build();
+    }
+
+    @Test
+    public void shouldBeCreatedFromConfigFile() {
+        File configFile = new File("src/test/resources/vrt_config_example.json");
+
+        VisualRegressionTrackerConfig config = VisualRegressionTrackerConfig.builder()
+                .configFile(configFile)
+                .build();
+
+        assertThat(config.getApiKey(), is("SECRET"));
+        assertThat(config.getApiUrl(), is("http://162.243.161.172:4200"));
+        assertThat(config.getProject(), is("VRT"));
+        assertThat(config.getBranchName(), is("master"));
+        assertThat(config.getEnableSoftAssert(), is(false));
+        assertThat(config.getCiBuildId(), is("SOME_UNIQUE_ID"));
+    }
+
+    @Test
+    public void shouldBeCreatedFromEnvironment() throws Exception {
+        EnvironmentVariables environmentVariables = new EnvironmentVariables("VRT_APIKEY", "SECRET")
+                .set("VRT_APIURL", "http://162.243.161.172:4200")
+                .set("VRT_PROJECT", "VRT")
+                .set("VRT_BRANCHNAME", "master")
+                .set("VRT_ENABLESOFTASSERT", "false")
+                .set("VRT_CIBUILDID", "SOME_UNIQUE_ID");
+
+        VisualRegressionTrackerConfig config = environmentVariables.execute(() ->
+                VisualRegressionTrackerConfig.builder()
+                        .build()
+        );
+
+        assertThat(config.getApiKey(), is("SECRET"));
+        assertThat(config.getApiUrl(), is("http://162.243.161.172:4200"));
+        assertThat(config.getProject(), is("VRT"));
+        assertThat(config.getBranchName(), is("master"));
+        assertThat(config.getEnableSoftAssert(), is(false));
+        assertThat(config.getCiBuildId(), is("SOME_UNIQUE_ID"));
+    }
+
+    @Test
+    public void shouldResolveFinalValuesInTheRightOrder() throws Exception {
+        EnvironmentVariables environmentVariables = new EnvironmentVariables("VRT_APIKEY", "ENV_SECRET")
+                .set("VRT_APIURL", "http://162.243.161.172:4201");
+        File configFile = new File("src/test/resources/vrt_config_example.json");
+
+        VisualRegressionTrackerConfig config = environmentVariables.execute(() ->
+                VisualRegressionTrackerConfig.builder()
+                        .apiUrl("http://localhost:4200")
+                        .configFile(configFile)
+                        .build()
+        );
+
+        assertThat(config.getApiKey(), is("ENV_SECRET"));
+        assertThat(config.getApiUrl(), is("http://localhost:4200"));
+        assertThat(config.getProject(), is("VRT"));
+        assertThat(config.getBranchName(), is("master"));
+        assertThat(config.getEnableSoftAssert(), is(false));
+        assertThat(config.getCiBuildId(), is("SOME_UNIQUE_ID"));
+    }
+
+
+    @Test
+    public void shouldUseDefaultValuesIfNotProvided() {
+        VisualRegressionTrackerConfig config = VisualRegressionTrackerConfig.builder()
+                        .apiUrl("http://localhost:4200")
+                        .apiKey("KEY")
+                        .project("PROJECT")
+                        .build();
+
+        assertThat(config.getEnableSoftAssert(), is(false));
+        assertThat(config.getHttpTimeoutInSeconds(), is(10));
+    }
+}

src/test/resources/vrt_config_example.json

@@ -0,0 +1,8 @@
+{
+  "apiUrl": "http://162.243.161.172:4200",
+  "project": "VRT",
+  "apiKey": "SECRET",
+  "branchName": "master",
+  "enableSoftAssert": false,
+  "ciBuildId": "SOME_UNIQUE_ID"
+}