🚧 Add step to wrap the OTEL context and mask the credentials

src/main/java/io/jenkins/plugins/opentelemetry/authentication/BearerTokenAuthentication.java

@@ -70,7 +70,7 @@ public void enrichOpenTelemetryAutoConfigureConfigProperties(Map<String, String>
     @Override
     public void enrichOtelEnvironmentVariables(Map<String, String> environmentVariables) {
         // TODO don't overwrite OTEL_EXPORTER_OTLP_HEADERS if already defined, just append to it
-        environmentVariables.put("OTEL_EXPORTER_OTLP_HEADERS", "authorization=Bearer " + this.getAuthenticationHeaderValue());
+        environmentVariables.put(OTelEnvironmentVariablesConventions.OTEL_EXPORTER_OTLP_HEADERS, "authorization=Bearer " + this.getAuthenticationHeaderValue());
     }
 
     public String getTokenId() {

src/main/java/io/jenkins/plugins/opentelemetry/authentication/HeaderAuthentication.java

@@ -63,7 +63,7 @@ public void enrichOpenTelemetryAutoConfigureConfigProperties(Map<String, String>
     @Override
     public void enrichOtelEnvironmentVariables(Map<String, String> environmentVariables) {
         // TODO don't overwrite OTEL_EXPORTER_OTLP_HEADERS if already defined, just append to it
-        environmentVariables.put("OTEL_EXPORTER_OTLP_HEADERS", this.getHeaderName() + "=" + this.getAuthenticationHeaderValue());
+        environmentVariables.put(OTelEnvironmentVariablesConventions.OTEL_EXPORTER_OTLP_HEADERS, this.getHeaderName() + "=" + this.getAuthenticationHeaderValue());
     }
 
     public String getHeaderName() {

src/main/java/io/jenkins/plugins/opentelemetry/semconv/OTelEnvironmentVariablesConventions.java

@@ -16,6 +16,7 @@ public class OTelEnvironmentVariablesConventions {
     public static final String OTEL_EXPORTER_OTLP_ENDPOINT = "OTEL_EXPORTER_OTLP_ENDPOINT";
     public static final String OTEL_EXPORTER_OTLP_INSECURE = "OTEL_EXPORTER_OTLP_INSECURE";
     public static final String OTEL_EXPORTER_OTLP_TIMEOUT = "OTEL_EXPORTER_OTLP_TIMEOUT";
+    public static final String OTEL_EXPORTER_OTLP_HEADERS = "OTEL_EXPORTER_OTLP_HEADERS";
 
     public static final String SPAN_ID = "SPAN_ID";
     public static final String TRACE_ID = "TRACE_ID";

src/main/java/io/jenkins/plugins/opentelemetry/steps/OpenTelemetryEnvBuildWrapper.java

@@ -0,0 +1,150 @@
+/*
+ * Copyright The Original Author or Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.jenkins.plugins.opentelemetry.steps;
+
+import hudson.EnvVars;
+import hudson.Extension;
+import hudson.FilePath;
+import hudson.Launcher;
+import hudson.console.ConsoleLogFilter;
+import hudson.console.LineTransformationOutputStream;
+import hudson.model.AbstractProject;
+import hudson.model.Run;
+import hudson.model.TaskListener;
+import hudson.tasks.BuildWrapperDescriptor;
+import io.jenkins.plugins.opentelemetry.JenkinsOpenTelemetryPluginConfiguration;
+import io.jenkins.plugins.opentelemetry.semconv.OTelEnvironmentVariablesConventions;
+import jenkins.tasks.SimpleBuildWrapper;
+import org.apache.commons.lang.StringUtils;
+import org.jenkinsci.Symbol;
+import org.kohsuke.stapler.DataBoundConstructor;
+import org.kohsuke.stapler.DataBoundSetter;
+
+import javax.inject.Inject;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.Serializable;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.regex.Pattern;
+
+/**
+ * A simple build wrapper to contribute OpenTelemetry environment variables.
+ */
+public class OpenTelemetryEnvBuildWrapper extends SimpleBuildWrapper {
+    private final static Logger LOGGER = Logger.getLogger(OpenTelemetryEnvBuildWrapper.class.getName());
+
+    private JenkinsOpenTelemetryPluginConfiguration jenkinsOpenTelemetryPluginConfiguration;
+
+    private String passwordToMask;
+    private boolean override;
+
+    @DataBoundConstructor
+    public OpenTelemetryEnvBuildWrapper() {
+    }
+
+    @DataBoundSetter
+    public void setOverride(boolean override) {
+        this.override = override;
+    }
+
+    @Override
+    public void setUp(Context context, Run<?, ?> build, FilePath workspace, Launcher launcher, TaskListener listener, EnvVars initialEnvironment) throws IOException, InterruptedException {
+        Map<String, String> otelConfiguration = jenkinsOpenTelemetryPluginConfiguration.getOtelConfigurationAsEnvironmentVariables();
+        for (Map.Entry<String, String> otelEnvironmentVariable : otelConfiguration.entrySet()) {
+            String envVarValue = otelEnvironmentVariable.getValue();
+            String envVarName = otelEnvironmentVariable.getKey();
+            if (envVarValue != null) {
+                // TODO: allow to override them option.
+                if (context.getEnv().containsKey(envVarName)) {
+                    LOGGER.log(Level.FINE, () -> "Overwrite environment variable '" + envVarName + "'");
+                }
+                context.env(envVarName, envVarValue);
+            }
+        }
+
+        String header = otelConfiguration.get(OTelEnvironmentVariablesConventions.OTEL_EXPORTER_OTLP_HEADERS);
+        if (header != null) {
+            this.passwordToMask = header;
+        }
+    }
+
+    @Override
+    public ConsoleLogFilter createLoggerDecorator(Run<?, ?> build) {
+        return new FilterImpl(passwordToMask);
+    }
+
+    @Override
+    public DescriptorImpl getDescriptor() {
+        return (DescriptorImpl) super.getDescriptor();
+    }
+
+    @Symbol("withOtelEnv")
+    @Extension
+    public static final class DescriptorImpl extends BuildWrapperDescriptor {
+
+        @Override
+        public boolean isApplicable(AbstractProject<?, ?> item) {
+            return true;
+        }
+
+        @Override
+        public String getDisplayName() {
+            return "Binds OpenTelemetry Environment Variables";
+        }
+    }
+
+    private static final class FilterImpl extends ConsoleLogFilter implements Serializable {
+        private static final long serialVersionUID = 10L;
+
+        private final String passwordToMask;
+
+        FilterImpl(String passwordToMask) {
+            this.passwordToMask = passwordToMask;
+        }
+
+        @Override
+        public OutputStream decorateLogger(Run _ignore, OutputStream logger) throws IOException, InterruptedException {
+            return new PasswordsMaskOutputStream(logger, passwordToMask);
+        }
+    }
+
+    /** Similar to {@code MaskPasswordsOutputStream}. */
+    public static final class PasswordsMaskOutputStream extends LineTransformationOutputStream {
+        private static final String MASKED_PASSWORD = "******";
+        private final OutputStream  logger;
+        private final Pattern passwordsAsPattern;
+
+        public PasswordsMaskOutputStream(OutputStream logger, String passwordToMask) {
+            this.logger = logger;
+
+            if (StringUtils.isNotEmpty(passwordToMask)) {
+                StringBuilder regex = new StringBuilder().append('(');
+                regex.append(Pattern.quote(passwordToMask));
+                regex.append(')');
+                this.passwordsAsPattern = Pattern.compile(regex.toString());
+            } else{
+                this.passwordsAsPattern = null;
+            }
+        }
+
+        @Override
+        protected void eol(byte[] bytes, int len) throws IOException {
+            String line = new String(bytes, 0, len, StandardCharsets.UTF_8);
+            if(passwordsAsPattern != null) {
+                line = passwordsAsPattern.matcher(line).replaceAll(MASKED_PASSWORD);
+            }
+            logger.write(line.getBytes(StandardCharsets.UTF_8));
+        }
+    }
+
+    @Inject
+    public void setJenkinsOpenTelemetryPluginConfiguration(JenkinsOpenTelemetryPluginConfiguration jenkinsOpenTelemetryPluginConfiguration) {
+        this.jenkinsOpenTelemetryPluginConfiguration = jenkinsOpenTelemetryPluginConfiguration;
+    }
+}

src/main/resources/io/jenkins/plugins/opentelemetry/steps/OpenTelemetryEnvBuildWrapper/config.jelly

@@ -0,0 +1,3 @@
+<?jelly escape-by-default='true'?>
+<j:jelly xmlns:j="jelly:core" xmlns:f="/lib/form">
+</j:jelly>

src/main/resources/io/jenkins/plugins/opentelemetry/steps/OpenTelemetryEnvBuildWrapper/help.html

@@ -0,0 +1,3 @@
+<div>
+    This step allows users to bind the OpenTelemetry configuration to environment variables.
+</div>