feat(logs): public capture API (PostHog.logger + PostHogLogsConfig)

.changeset/logs-public-api.md

@@ -0,0 +1,6 @@
+---
+"posthog": minor
+"posthog-android": minor
+---
+
+Add public Logs API: `PostHog.logger.trace/debug/info/warn/error/fatal(message, attrs?)` plus a `PostHogLogsConfig` for serviceName, environment, resourceAttributes, rate cap, and `addBeforeSend` redaction hooks. Logs ship via OTLP/JSON to `/i/v1/logs` and pick up auto-attached attributes (`app.state`, distinctId, sessionId, screen name, feature flags). Matches the equivalent surfaces on posthog-ios and posthog-react-native.

posthog-samples/posthog-android-sample/src/main/AndroidManifest.xml

@@ -16,6 +16,11 @@
         android:theme="@style/Theme.PostHogAndroidSample"
         tools:targetApi="34"
         android:name=".MyApp">
+        <activity
+            android:name="com.posthog.android.sample.LogsActivity"
+            android:exported="false"
+            android:theme="@style/Theme.PostHogAndroidSample" />
+
         <activity
             android:name="com.posthog.android.sample.NormalActivity"
             android:exported="true"

posthog-samples/posthog-android-sample/src/main/java/com/posthog/android/sample/LogsActivity.kt

@@ -0,0 +1,87 @@
+package com.posthog.android.sample
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.posthog.PostHog
+import com.posthog.android.sample.ui.theme.postHogAndroidSampleTheme
+
+class LogsActivity : ComponentActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        setContent {
+            postHogAndroidSampleTheme {
+                Surface(
+                    modifier = Modifier.fillMaxSize(),
+                    color = MaterialTheme.colorScheme.background,
+                ) {
+                    Column(
+                        modifier = Modifier.padding(16.dp),
+                        verticalArrangement = Arrangement.spacedBy(12.dp),
+                    ) {
+                        logsDemo()
+                    }
+                }
+            }
+        }
+    }
+}
+
+/**
+ * Dogfood section for the logs API. Tap each row to capture a log; the
+ * "Last action" line shows what fired.
+ */
+@Composable
+fun logsDemo(modifier: Modifier = Modifier) {
+    var lastAction by remember { mutableStateOf("") }
+    val attrs = mapOf("source" to "android-sample")
+    val items =
+        listOf(
+            "trace" to { PostHog.logger.trace("LogsActivity trace tap", attrs) },
+            "debug" to { PostHog.logger.debug("LogsActivity debug tap", attrs) },
+            "info" to { PostHog.logger.info("LogsActivity info tap", attrs) },
+            "warn" to { PostHog.logger.warn("LogsActivity warn tap", attrs) },
+            "error" to { PostHog.logger.error("LogsActivity error tap", attrs) },
+            "fatal" to { PostHog.logger.fatal("LogsActivity fatal tap", attrs) },
+        )
+    Column(verticalArrangement = Arrangement.spacedBy(8.dp), modifier = modifier) {
+        Text("Logs (tap to capture):")
+        items.forEach { (label, onTap) ->
+            Text(
+                text = "  • $label",
+                modifier =
+                    Modifier.clickable {
+                        onTap()
+                        lastAction = "Sent $label"
+                    },
+            )
+        }
+        Text(
+            text = "  • flush all queues",
+            modifier =
+                Modifier.clickable {
+                    PostHog.flush()
+                    lastAction = "flush() called"
+                },
+        )
+        if (lastAction.isNotEmpty()) {
+            Text("Last action: $lastAction")
+        }
+    }
+}

posthog-samples/posthog-android-sample/src/main/java/com/posthog/android/sample/MyApp.kt

@@ -43,6 +43,8 @@ class MyApp : Application() {
                 sessionReplayConfig.screenshot = true
                 surveys = false
                 errorTrackingConfig.autoCapture = false
+                logs.serviceName = "posthog-android-sample"
+                logs.environment = "development"
             }
         PostHogAndroid.setup(this, config)
     }

posthog-samples/posthog-android-sample/src/main/java/com/posthog/android/sample/NormalActivity.kt

@@ -29,6 +29,11 @@ class NormalActivity : ComponentActivity() {
             startActivity(Intent(this, SessionReplayActivity::class.java))
         }
 
+        val logsButton = findViewById<Button>(R.id.logsButton)
+        logsButton.setOnClickListener {
+            startActivity(Intent(this, LogsActivity::class.java))
+        }
+
         val button = findViewById<Button>(R.id.button)
 //        val editText = findViewById<EditText>(R.id.editText)
 //        val imvAndroid = findViewById<ImageView>(R.id.imvAndroid)

posthog-samples/posthog-android-sample/src/main/res/layout/normal_activity.xml

@@ -48,6 +48,13 @@
         android:id="@+id/sessionReplayButton"
         />
 
+    <Button
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Logs"
+        android:id="@+id/logsButton"
+        />
+
     <!--            &lt;!&ndash;    <View&ndash;&gt;-->
     <!--            &lt;!&ndash;        android:layout_width="match_parent"&ndash;&gt;-->
     <!--            &lt;!&ndash;        android:layout_height="5dp"&ndash;&gt;-->