Merge pull request #1 from a7d-corp/initial-setup

Initial commit of ingestion API app

Author: glitchcrab

.env.example

@@ -0,0 +1,17 @@
+# InfluxDB connection
+INFLUX_URL=http://localhost:8086
+INFLUX_TOKEN=your-token-here
+INFLUX_ORG=health
+INFLUX_BUCKET=health_data
+
+# API authentication
+INGESTION_API_KEY=your-api-key-here
+
+# Server
+PORT=8080
+
+# Write behaviour
+INFLUX_BATCH_SIZE=500        # Max points per write call
+INFLUX_FLUSH_INTERVAL_MS=1000
+INFLUX_MAX_RETRIES=3
+INFLUX_RETRY_INTERVAL_MS=500

Dockerfile

@@ -0,0 +1,15 @@
+FROM golang:1.22-alpine AS builder
+WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux go build \
+    -ldflags "-X main.version=$(git rev-parse --short HEAD 2>/dev/null || echo dev)" \
+    -o health-ingestion .
+
+FROM alpine:3.19
+RUN apk --no-cache add ca-certificates tzdata
+WORKDIR /app
+COPY --from=builder /app/health-ingestion .
+EXPOSE 8080
+ENTRYPOINT ["./health-ingestion"]

README.md

@@ -1 +1,48 @@
 # apple-health-ingestor
+
+HTTP API that receives JSON payloads from the [Health Auto Export](https://www.healthautoexport.com/) iOS app and writes the data to InfluxDB v2.
+
+## Configuration
+
+Copy `.env.example` to `.env` and fill in the values. All variables are required except `PORT`.
+
+| Variable | Default | Description |
+|---|---|---|
+| `INFLUX_URL` | — | InfluxDB URL |
+| `INFLUX_TOKEN` | — | InfluxDB API token |
+| `INFLUX_ORG` | — | InfluxDB org name |
+| `INFLUX_BUCKET` | — | InfluxDB bucket name |
+| `INGESTION_API_KEY` | — | API key for the `/ingest` endpoint |
+| `PORT` | `8080` | HTTP listen port |
+| `INFLUX_BATCH_SIZE` | `500` | Max points per write call |
+| `INFLUX_FLUSH_INTERVAL_MS` | `1000` | Write flush interval (ms) |
+| `INFLUX_MAX_RETRIES` | `3` | Write retry attempts |
+| `INFLUX_RETRY_INTERVAL_MS` | `500` | Delay between retries (ms) |
+
+## Health Auto Export setup
+
+1. Install [Health Auto Export](https://www.healthautoexport.com/) on your iPhone.
+2. Go to **Automations** → **Add Automation**.
+3. Set **Export Format** to `JSON` and **Export Type** to `REST API`.
+4. Set the URL to `http://<your-host>:<PORT>/ingest`.
+5. Add a header: `X-API-Key: <your INGESTION_API_KEY>`.
+6. Choose the metrics/workouts to export and set a sync interval.
+
+## Running
+
+```bash
+# Build and run
+go build -o health-ingestion .
+./health-ingestion
+
+# Docker
+docker build -t health-ingestion .
+docker run --env-file .env -p 8080:8080 health-ingestion
+```
+
+## API
+
+| Method | Path | Auth | Description |
+|---|---|---|---|
+| `POST` | `/ingest` | `X-API-Key` header | Ingest Health Auto Export payload |
+| `GET` | `/health` | none | Liveness check |

go.mod

@@ -0,0 +1,45 @@
+module health-ingestion
+
+go 1.22
+
+require (
+	github.com/gin-gonic/gin v1.10.0
+	github.com/go-playground/validator/v10 v10.22.0
+	github.com/influxdata/influxdb-client-go/v2 v2.13.0
+	github.com/joho/godotenv v1.5.1
+	github.com/stretchr/testify v1.9.0
+)
+
+require (
+	github.com/apapsch/go-jsonmerge/v2 v2.0.0 // indirect
+	github.com/bytedance/sonic v1.11.6 // indirect
+	github.com/bytedance/sonic/loader v0.1.1 // indirect
+	github.com/cloudwego/base64x v0.1.4 // indirect
+	github.com/cloudwego/iasm v0.2.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
+	github.com/gin-contrib/sse v0.1.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/google/uuid v1.3.1 // indirect
+	github.com/influxdata/line-protocol v0.0.0-20200327222509-2487e7298839 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/oapi-codegen/runtime v1.0.0 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.2.12 // indirect
+	golang.org/x/arch v0.8.0 // indirect
+	golang.org/x/crypto v0.23.0 // indirect
+	golang.org/x/net v0.25.0 // indirect
+	golang.org/x/sys v0.20.0 // indirect
+	golang.org/x/text v0.15.0 // indirect
+	google.golang.org/protobuf v1.34.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,105 @@
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+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+nullprogram.com/x/optparse v1.0.0/go.mod h1:KdyPE+Igbe0jQUrVfMqDMeJQIJZEuyV7pjYmp6pbG50=
+rsc.io/pdf v0.1.1/go.mod h1:n8OzWcQ6Sp37PL01nO98y4iUCRdTGarVfzxY20ICaU4=

internal/config/config.go

@@ -0,0 +1,73 @@
+// Package config handles loading and validating configuration from environment variables.
+package config
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+// Config holds all runtime configuration for the service.
+type Config struct {
+	InfluxURL             string
+	InfluxToken           string
+	InfluxOrg             string
+	InfluxBucket          string
+	IngestionAPIKey       string
+	Port                  string
+	InfluxBatchSize       int
+	InfluxFlushIntervalMS int
+	InfluxMaxRetries      int
+	InfluxRetryIntervalMS int
+}
+
+// Load reads configuration from environment variables.
+// It returns an error listing all missing required variables so the caller can
+// fail fast with a single descriptive message.
+func Load() (Config, error) {
+	cfg := Config{}
+	var missing []string
+
+	required := func(key string) string {
+		v := os.Getenv(key)
+		if v == "" {
+			missing = append(missing, key)
+		}
+		return v
+	}
+
+	cfg.InfluxURL = required("INFLUX_URL")
+	cfg.InfluxToken = required("INFLUX_TOKEN")
+	cfg.InfluxOrg = required("INFLUX_ORG")
+	cfg.InfluxBucket = required("INFLUX_BUCKET")
+	cfg.IngestionAPIKey = required("INGESTION_API_KEY")
+
+	if len(missing) > 0 {
+		return Config{}, fmt.Errorf("missing required environment variables: %v", missing)
+	}
+
+	cfg.Port = os.Getenv("PORT")
+	if cfg.Port == "" {
+		cfg.Port = "8080"
+	}
+
+	cfg.InfluxBatchSize = envInt("INFLUX_BATCH_SIZE", 500)
+	cfg.InfluxFlushIntervalMS = envInt("INFLUX_FLUSH_INTERVAL_MS", 1000)
+	cfg.InfluxMaxRetries = envInt("INFLUX_MAX_RETRIES", 3)
+	cfg.InfluxRetryIntervalMS = envInt("INFLUX_RETRY_INTERVAL_MS", 500)
+
+	return cfg, nil
+}
+
+// envInt reads an integer environment variable, returning def if absent or unparseable.
+func envInt(key string, def int) int {
+	s := os.Getenv(key)
+	if s == "" {
+		return def
+	}
+	v, err := strconv.Atoi(s)
+	if err != nil {
+		return def
+	}
+	return v
+}

internal/handler/health.go

@@ -0,0 +1,16 @@
+// Package handler contains the HTTP handler functions for the health ingestion API.
+package handler
+
+import (
+	"github.com/gin-gonic/gin"
+)
+
+// Version is injected at build time via ldflags: -X main.version=<sha>.
+// The main package sets handler.Version = version after loading it from the linker.
+var Version = "dev"
+
+// Health handles GET /health and returns a simple liveness response.
+// It is unauthenticated and is suitable for use as a load-balancer health check.
+func Health(c *gin.Context) {
+	c.JSON(200, gin.H{"status": "ok", "version": Version})
+}

internal/handler/health_test.go

@@ -0,0 +1,33 @@
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func init() {
+	gin.SetMode(gin.TestMode)
+}
+
+func TestHealthCheck(t *testing.T) {
+	r := gin.New()
+	r.GET("/health", Health)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, "/health", nil)
+	r.ServeHTTP(w, req)
+
+	assert.Equal(t, http.StatusOK, w.Code)
+
+	var body map[string]interface{}
+	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &body))
+	assert.Equal(t, "ok", body["status"])
+	_, hasVersion := body["version"]
+	assert.True(t, hasVersion)
+}