Expose HTTP endpoint to trigger a poll (#48)

* expose HTTP endpoint to trigger a poll

* add Procfile

* update CI & CD configs

* add basic auth

* add warning logs

* update readme & improve logging

.github/workflows/ci.yml

@@ -22,8 +22,11 @@ jobs:
     - name: Make sure that go.mod has already been tidied
       run: go mod tidy && git diff --no-patch --exit-code
 
-    - name: Build
-      run: go build ./cmd/entrello
+    - name: Build Runner
+      run: go build ./cmd/runner
+
+    - name: Build Server
+      run: go build ./cmd/server
 
     - name: Run tests
       run: go test -covermode=count -coverprofile=profile.cov ./...

.goreleaser.yml

@@ -3,9 +3,24 @@ before:
     - go mod download
 
 builds:
-- id: entrello
-  main: ./cmd/entrello
-  binary: entrello
+- id: entrello-runner
+  main: ./cmd/runner
+  binary: entrello-runner
+  env:
+  - CGO_ENABLED=0
+  goos:
+    - linux
+    - darwin
+    - windows
+  goarch:
+    - amd64
+    - arm
+    - arm64
+  goarm: [6, 7]
+
+- id: entrello-server
+  main: ./cmd/server
+  binary: entrello-server
   env:
   - CGO_ENABLED=0
   goos:
@@ -28,7 +43,8 @@ archives:
       {{- end -}}
     {{- end -}}
   builds:
-    - entrello
+    - entrello-runner
+    - entrello-server
   replacements:
     386: i386
     amd64: x86_64

Procfile

@@ -0,0 +1 @@
+web: bin/server

README.md

@@ -4,23 +4,35 @@
 [![Go Report Card](https://goreportcard.com/badge/github.com/utkuufuk/entrello)](https://goreportcard.com/report/github.com/utkuufuk/entrello)
 [![Coverage Status](https://coveralls.io/repos/github/utkuufuk/entrello/badge.svg)](https://coveralls.io/github/utkuufuk/entrello)
 
-Polls compatible data sources and keeps your Trello cards synchronized with fresh data. Meant to be run as a scheduled job.
+Polls compatible data sources and keeps your Trello cards synchronized with fresh data.
 
 Let's say you have an HTTP endpoint that returns GitHub issues assigned to you upon a `GET` request.
 You can point `entrello` to that endpoint to keep your GitHub issues synchronized in your Trello board.
 
 Each data source must return a JSON array of Trello card objects upon a `GET` request. You can import and use the `NewCard` function from `pkg/trello/trello.go` in order to construct Trello card objects.
 
+- Can be run as a scheduled job:
+    ```sh
+    go run ./cmd/runner
+    ```
+- Can be run as an HTTP server:
+    ```sh
+    PORT=<port> USERNAME=<user> PASSWORD=<password> go run ./cmd/server
+    ```
+
+    In this case, the runner can be triggered by a `POST` request to the server like this:
+    ```sh
+    curl -d @config.json <SERVER_URL> -H "Authorization: Basic <base64(<user>:<password>)>"
+    ```
+
 ## Configuration
 Copy and rename `config.example.json` as `config.json` (default), then set your own values in `config.json`.
 
 You can also use a custom config file path using the `-c` flag:
 ```sh
-go run ./cmd/entrello -c /path/to/config/file
+go run ./cmd/runner -c /path/to/config/file
 ```
 
-Alternatively, you can store the configuration inside the `ENTRELLO_CONFIG` environment variable as a JSON string.
-
 ### Trello
 You need to set your [Trello API key & token](https://trello.com/app-key) in the configuraiton file, as well as the Trello board ID.
 
@@ -65,15 +77,9 @@ For each data source, the following parameters have to be specified. (See `confi
     ```
 
 ## Example Cron Job
-Make sure that the cron job runs frequently enough to keep up with the most frequent custom interval in your configuration.
-
-For instance, it wouldn't make sense to define a custom period of 15 minutes while the cron job only runs every hour.
-
-Both of the following jobs run every hour and both assume that `config.json` is located in the current working directory, or its contents are stored within the `ENTRELLO_CONFIG` environment variable.
+Assuming `config.json` is located in the current working directory:
 ``` sh
-# using "go run"
-0 * * * * cd /home/you/git/entrello && /usr/local/go/bin/go run ./cmd/entrello
-
-# use binary executable (see releases: https://github.com/you/entrello/releases)
-0 * * * * cd /path/to/binary && ./entrello
+0 * * * * cd /home/you/git/entrello && /usr/local/go/bin/go run ./cmd/runner
 ```
+
+Make sure that the cron job runs frequently enough to keep up with the most frequent custom interval in your configuration. For instance, it wouldn't make sense to define a custom period of 15 minutes while the cron job only runs every hour.

cmd/runner/main.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"flag"
+	"log"
+
+	"github.com/utkuufuk/entrello/internal/config"
+	"github.com/utkuufuk/entrello/internal/logger"
+	"github.com/utkuufuk/entrello/internal/service"
+)
+
+func main() {
+	var configFile string
+	flag.StringVar(&configFile, "c", "config.json", "config file path")
+	flag.Parse()
+
+	cfg, err := config.ReadConfig(configFile)
+	if err != nil {
+		log.Fatalf("Could not read configuration: %v", err)
+	}
+
+	if err = service.Poll(cfg); err != nil {
+		logger.Error(err.Error())
+	}
+}

cmd/server/main.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+
+	"github.com/utkuufuk/entrello/internal/config"
+	"github.com/utkuufuk/entrello/internal/logger"
+	"github.com/utkuufuk/entrello/internal/service"
+)
+
+func main() {
+	http.HandleFunc("/", handler)
+	http.ListenAndServe(fmt.Sprintf(":%s", os.Getenv("PORT")), nil)
+}
+
+func handler(w http.ResponseWriter, req *http.Request) {
+	if req.Method != http.MethodPost {
+		logger.Warn("Method %s not allowed", req.Method)
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		return
+	}
+
+	user, pwd, ok := req.BasicAuth()
+	if !ok {
+		logger.Warn("Could not parse basic auth.")
+		w.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+	if user != os.Getenv("USERNAME") {
+		logger.Warn("Invalid user name: %s", user)
+		w.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+	if pwd != os.Getenv("PASSWORD") {
+		logger.Warn("Invalid password: %s", pwd)
+		w.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+
+	body, err := ioutil.ReadAll(req.Body)
+	if err != nil {
+		logger.Error("Could not read request body: %v", err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	var cfg config.Config
+	if err = json.Unmarshal(body, &cfg); err != nil {
+		logger.Warn("Invalid request body: %v", err)
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if err = service.Poll(cfg); err != nil {
+		logger.Error(err.Error())
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+}

go.mod

@@ -1,6 +1,7 @@
 module github.com/utkuufuk/entrello
 
-go 1.13
+// +heroku goVersion go1.16
+go 1.16
 
 require (
 	github.com/adlio/trello v1.8.0

internal/config/config.go

@@ -4,8 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
-
-	"github.com/utkuufuk/entrello/internal/logger"
 )
 
 const (
@@ -42,18 +40,6 @@ type Config struct {
 }
 
 func ReadConfig(fileName string) (cfg Config, err error) {
-	jsonStr := os.Getenv("ENTRELLO_CONFIG")
-	if jsonStr != "" {
-		logger.Info("Attempting to read configuration from environment variable 'ENTRELLO_CONFIG'")
-		err = json.Unmarshal([]byte(jsonStr), &cfg)
-		if err != nil {
-			return cfg, fmt.Errorf("could not parse config stored in the environment variable: %s", err)
-		}
-
-		return cfg, nil
-	}
-
-	logger.Info("Attempting to read configuration from file '%s'", fileName)
 	f, err := os.Open(fileName)
 	if err != nil {
 		return cfg, fmt.Errorf("could not open config file: %v", err)

internal/service/poller.go

@@ -0,0 +1,40 @@
+package service
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/utkuufuk/entrello/internal/config"
+	"github.com/utkuufuk/entrello/pkg/trello"
+)
+
+func Poll(cfg config.Config) error {
+	loc, err := time.LoadLocation(cfg.TimezoneLocation)
+	if err != nil {
+		return fmt.Errorf("invalid timezone location: %v", loc)
+	}
+
+	sources, labels := getSources(cfg.Sources, time.Now().In(loc))
+	if len(sources) == 0 {
+		return nil
+	}
+
+	client, err := trello.NewClient(cfg.Trello)
+	if err != nil {
+		return fmt.Errorf("could not create trello client: %v", err)
+	}
+
+	if err := client.LoadBoard(labels); err != nil {
+		return fmt.Errorf("Could not load existing cards from the board: %v", err)
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(len(sources))
+	for _, src := range sources {
+		go process(src, client, &wg)
+	}
+	wg.Wait()
+
+	return nil
+}

cmd/entrello/source.go → internal/service/source.go

@@ -1,4 +1,4 @@
-package main
+package service
 
 import (
 	"encoding/json"

cmd/entrello/source_test.go → internal/service/source_test.go

@@ -1,4 +1,4 @@
-package main
+package service
 
 import (
 	"fmt"