Feat/fetch retry and error handling

README.md

@@ -19,6 +19,7 @@ $ yarn add datadog-winston
 - **ddsource**: The technology from which the logs originated
 - **ddtags**: Metadata assoicated with the logs
 - **intakeRegion**: The datadog intake to use. set to `eu` to force logs to be sent to the EU specific intake
+- **retries**: The number of retry attempts to make sending logs to DataDog if there are communication errors. Defaults to 0, i.e. no retries
 
 ## Usage
 ```javascript
@@ -36,7 +37,8 @@ logger.add(
     hostname: 'my_machine',
     service: 'super_service',
     ddsource: 'nodejs',
-    ddtags: 'foo:bar,boo:baz'
+    ddtags: 'foo:bar,boo:baz',
+    retries: 5
   })
 )
 ```

__tests__/index.js

@@ -83,4 +83,90 @@ describe('DatadogTransport#log(info, callback)', () => {
         expect(scope.isDone()).toBe(true)
       })
     })
+  it('Retries transient errors', async () => {
+    const body = JSON.stringify({
+      dd: {
+        trace_id: 'abc',
+        span_id: 'def'
+      },
+      foo: 'bar'
+    })
+
+    const query = {
+      service: 'service',
+      ddsource: 'ddsource',
+      ddtags: 'env:production,trace_id:abc,span_id:def,tag_a:value_a,tag_b:value_b',
+      hostname: 'hostname'
+    }
+
+    const scope = nock('https://http-intake.logs.datadoghq.com')
+      .post('/v1/input/apikey', body).query(query).once().reply(501)
+      .post('/v1/input/apikey', body).query(query).once().reply(204)
+
+    const opts = Object.assign({}, {
+      apiKey: 'apikey',
+      service: 'service',
+      ddsource: 'ddsource',
+      ddtags: 'env:production',
+      hostname: 'hostname',
+      retries: 1
+    }, {})
+
+    const transport = new DatadogTransport(opts)
+    const callback = jest.fn()
+    await transport.log({
+      dd: {
+        trace_id: 'abc',
+        span_id: 'def'
+      },
+      foo: 'bar',
+      ddtags: 'tag_a:value_a,tag_b:value_b'
+    }, callback)
+
+    expect(scope.isDone()).toBe(true)
+    expect(callback).toHaveBeenCalled()
+  })
+  it('Does not retries persistent errors', async () => {
+    const body = JSON.stringify({
+      dd: {
+        trace_id: 'abc',
+        span_id: 'def'
+      },
+      foo: 'bar'
+    })
+
+    const query = {
+      service: 'service',
+      ddsource: 'ddsource',
+      ddtags: 'env:production,trace_id:abc,span_id:def,tag_a:value_a,tag_b:value_b',
+      hostname: 'hostname'
+    }
+
+    const scope = nock('https://http-intake.logs.datadoghq.com')
+      .post('/v1/input/apikey', body).query(query).once().reply(401)
+      .post('/v1/input/apikey', body).query(query).once().reply(204)
+
+    const opts = Object.assign({}, {
+      apiKey: 'apikey',
+      service: 'service',
+      ddsource: 'ddsource',
+      ddtags: 'env:production',
+      hostname: 'hostname',
+      retries: 1
+    }, {})
+
+    const transport = new DatadogTransport(opts)
+    const callback = jest.fn()
+    await transport.log({
+      dd: {
+        trace_id: 'abc',
+        span_id: 'def'
+      },
+      foo: 'bar',
+      ddtags: 'tag_a:value_a,tag_b:value_b'
+    }, callback)
+
+    expect(scope.isDone()).toBe(false)
+    expect(callback).toHaveBeenCalled()
+  })
 })

lib/index.js

@@ -1,5 +1,6 @@
 const Transport = require('winston-transport')
 const querystring = require('querystring')
+const retry = require('async-retry')
 const fetch = require('node-fetch')
 
 /**
@@ -74,15 +75,24 @@ module.exports = class DatadogTransport extends Transport {
     const api = querystring ? `${this.api}?${queryString}` : this.api
 
     try {
-      // Perform the writing to the remote service
-      await fetch(api, {
-        method: 'POST',
-        headers: {
-          'content-type': 'application/json'
-        },
-        body: JSON.stringify(logs)
-      })
+      await retry(async bail => {
+        const res = await fetch(api, {
+          method: 'POST',
+          headers: {
+            'content-type': 'application/json'
+          },
+          body: JSON.stringify(logs)
+        })
+
+        if (res.status >= 500) {
+          throw new Error('Retryable error from DataDog API')
+        }
+        if (res.status >= 400) {
+          bail()
+        }
+      }, { retries: this.opts.retries || 0 })
     } catch (err) {
+      // Just throw the error away as there's nothing more we can do
     } finally {
       callback()
     }

package.json

@@ -1,13 +1,14 @@
 {
   "name": "datadog-winston",
-  "version": "1.5.0",
+  "version": "1.5.2",
   "description": "Ship winston logs to datadog without breaking a sweat",
   "main": "index.js",
   "repository": "https://github.com/itsfadnis/datadog-winston.git",
   "author": "itsfadnis <[email protected]>",
   "license": "MIT",
   "dependencies": {
     "@babel/runtime": "^7.4.5",
+    "async-retry": "^1.3.1",
     "node-fetch": "^2.6.0",
     "winston-transport": "^4.3.0"
   },

yarn.lock

@@ -1052,6 +1052,13 @@ async-limiter@~1.0.0:
   resolved "https://registry.yarnpkg.com/async-limiter/-/async-limiter-1.0.0.tgz#78faed8c3d074ab81f22b4e985d79e8738f720f8"
   integrity sha512-jp/uFnooOiO+L211eZOoSyzpOITMXx1rBITauYykG3BRYPu8h0UcxsPNB04RR5vo4Tyz3+ay17tR6JVf9qzYWg==
 
+async-retry@^1.3.1:
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/async-retry/-/async-retry-1.3.1.tgz#139f31f8ddce50c0870b0ba558a6079684aaed55"
+  integrity sha512-aiieFW/7h3hY0Bq5d+ktDBejxuwR78vRu9hDUdR8rNhSaQ29VzPL4AoIRG7D/c7tdenwOcKvgPM6tIxB3cB6HA==
+  dependencies:
+    retry "0.12.0"
+
 asynckit@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/asynckit/-/asynckit-0.4.0.tgz#c79ed97f7f34cb8f2ba1bc9790bcc366474b4b79"
@@ -4279,6 +4286,11 @@ ret@~0.1.10:
   resolved "https://registry.yarnpkg.com/ret/-/ret-0.1.15.tgz#b8a4825d5bdb1fc3f6f53c2bc33f81388681c7bc"
   integrity sha512-TTlYpa+OL+vMMNG24xSlQGEJ3B/RzEfUlLct7b5G/ytav+wPrplCpVMFuwzXbkecJrb6IYo1iFb0S9v37754mg==
 
+[email protected]:
+  version "0.12.0"
+  resolved "https://registry.yarnpkg.com/retry/-/retry-0.12.0.tgz#1b42a6266a21f07421d1b0b54b7dc167b01c013b"
+  integrity sha1-G0KmJmoh8HQh0bC1S33BZ7AcATs=
+
 rimraf@^2.5.4, rimraf@^2.6.1, rimraf@^2.6.3, rimraf@~2.6.2:
   version "2.6.3"
   resolved "https://registry.yarnpkg.com/rimraf/-/rimraf-2.6.3.tgz#b2d104fe0d8fb27cf9e0a1cda8262dd3833c6cab"
@@ -5104,4 +5116,4 @@ yargs@^12.0.2:
     string-width "^2.0.0"
     which-module "^2.0.0"
     y18n "^3.2.1 || ^4.0.0"
-    yargs-parser "^11.1.1"
+    yargs-parser "^11.1.1"