feat: add backend plugin to make alerting possible (#37)

This PR implements the backend part of the plugin. This makes it
possible to, for example, create alerts in Grafana, based on data
retrieved from Parseable.

Example of creating an alert:

https://github.com/parseablehq/parseable-datasource/assets/49564025/41cd6e5a-5131-48a4-8d6f-69513b05c7aa

.github/workflows/ci.yaml

@@ -59,7 +59,7 @@ jobs:
         if: steps.check-for-backend.outputs.has-backend == 'true'
         uses: actions/setup-go@v2
         with:
-          go-version: "1.15"
+          go-version: "1.21"
 
       - name: Test backend
         if: steps.check-for-backend.outputs.has-backend == 'true'
@@ -73,4 +73,4 @@ jobs:
         uses: magefile/mage-action@v1
         with:
           version: latest
-          args: buildAll
+          args: buildAll

Magefile.go

@@ -0,0 +1,38 @@
+//go:build mage
+// +build mage
+package main
+
+import (
+	"github.com/magefile/mage/mg"
+
+	// mage:import
+	build "github.com/grafana/grafana-plugin-sdk-go/build"
+	"github.com/magefile/mage/sh"
+	"os"
+	"path"
+)
+
+// Default configures the default target.
+var Default = build.BuildAll
+
+// Server builds the example server inside cmd/server
+func Server() error {
+	os.Chdir(path.Join("cmd", "server"))
+	defer os.Chdir(path.Join("..", ".."))
+	if err := sh.Run("go", "build", "-v"); err != nil {
+		return err
+	}
+	return nil
+}
+
+// CleanAll runs the 'clean' target and also removes the example server binary in cmd/server
+func CleanAll() error {
+	mg.Deps(build.Clean)
+	return os.Remove(path.Join("cmd", "server", "server"))
+}
+
+// TestAll runs all test for the backend (go test ./...), it's different than 'test', which runs tests only
+// in the pkg package.
+func TestAll() error {
+	return sh.RunV("go", "test", "./...")
+}

go.mod

@@ -0,0 +1,93 @@
+module github.com/parseablehq/parseable-datasource
+
+go 1.20
+
+require (
+	github.com/grafana/grafana-plugin-sdk-go v0.187.0
+	github.com/magefile/mage v1.15.0
+	github.com/stretchr/testify v1.8.4
+	go.opentelemetry.io/otel v1.19.0
+	go.opentelemetry.io/otel/trace v1.19.0
+)
+
+require (
+	cloud.google.com/go/compute/metadata v0.2.3 // indirect
+	github.com/BurntSushi/toml v1.3.2 // indirect
+	github.com/apache/arrow/go/v13 v13.0.0 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/cheekybits/genny v1.0.0 // indirect
+	github.com/chromedp/cdproto v0.0.0-20220208224320-6efb837e6bc2 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/elazarl/goproxy v0.0.0-20230731152917-f99041a5c027 // indirect
+	github.com/fatih/color v1.15.0 // indirect
+	github.com/getkin/kin-openapi v0.120.0 // indirect
+	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/go-openapi/jsonpointer v0.19.6 // indirect
+	github.com/go-openapi/swag v0.22.4 // indirect
+	github.com/goccy/go-json v0.10.0 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/google/flatbuffers v23.1.21+incompatible // indirect
+	github.com/google/go-cmp v0.5.9 // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/mux v1.8.0 // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware v1.4.0 // indirect
+	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.16.2 // indirect
+	github.com/hashicorp/go-hclog v1.5.0 // indirect
+	github.com/hashicorp/go-plugin v1.4.9 // indirect
+	github.com/hashicorp/yamux v0.1.1 // indirect
+	github.com/invopop/yaml v0.2.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/compress v1.15.15 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.3 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/mattetti/filebuffer v1.0.1 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.18 // indirect
+	github.com/mattn/go-runewidth v0.0.9 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/mitchellh/go-testing-interface v1.14.1 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 // indirect
+	github.com/oklog/run v1.1.0 // indirect
+	github.com/olekukonko/tablewriter v0.0.5 // indirect
+	github.com/perimeterx/marshmallow v1.1.5 // indirect
+	github.com/pierrec/lz4/v4 v4.1.17 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/prometheus/client_golang v1.14.0 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.42.0 // indirect
+	github.com/prometheus/procfs v0.8.0 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/unknwon/bra v0.0.0-20200517080246-1e3013ecaff8 // indirect
+	github.com/unknwon/com v1.0.1 // indirect
+	github.com/unknwon/log v0.0.0-20150304194804-e617c87089d3 // indirect
+	github.com/urfave/cli v1.22.14 // indirect
+	github.com/zeebo/xxh3 v1.0.2 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.45.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/httptrace/otelhttptrace v0.45.0 // indirect
+	go.opentelemetry.io/contrib/propagators/jaeger v1.20.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.19.0 // indirect
+	go.opentelemetry.io/otel/metric v1.19.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.19.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.0.0 // indirect
+	golang.org/x/mod v0.9.0 // indirect
+	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/sys v0.13.0 // indirect
+	golang.org/x/text v0.13.0 // indirect
+	golang.org/x/tools v0.6.0 // indirect
+	golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20230731193218-e0aa005b6bdf // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230731193218-e0aa005b6bdf // indirect
+	google.golang.org/grpc v1.58.2 // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
+	gopkg.in/fsnotify/fsnotify.v1 v1.4.7 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)