feat(push): push only updated parameters

Check before pushing parameters which parameters need to be changed. This makes browsing in AWS
Console more clear when checking parameter history. Before this change there could be 2 history
records with the same value.

package.json

@@ -28,7 +28,7 @@
   "dependencies": {
     "@aws-sdk/client-ssm": "^3.35.0",
     "dotenv": "^10.0.0",
-    "lodash.sortby": "^4.7.0",
+    "lodash": "^4.17.21",
     "meow": "^10.1.1"
   },
   "devDependencies": {

src/client.mjs

@@ -0,0 +1,41 @@
+import { SSMClient } from '@aws-sdk/client-ssm'
+
+export function createClient({ region, accessKeyId, secretAccessKey }) {
+  const credentials =
+    accessKeyId && secretAccessKey
+      ? {
+          accessKeyId,
+          secretAccessKey,
+        }
+      : undefined
+
+  return new SSMClient({ region, credentials })
+}
+
+async function delay(time) {
+  return new Promise((resolve) => setTimeout(resolve, time))
+}
+
+export function addThrottleMiddleware(client, { batchSize, wait }) {
+  let currentBatchSize = 0
+
+  // https://aws.amazon.com/blogs/developer/middleware-stack-modular-aws-sdk-js/
+  client.middlewareStack.add(
+    (next) => async (args) => {
+      if (currentBatchSize > batchSize) {
+        currentBatchSize = 0
+
+        await delay(wait)
+      }
+
+      currentBatchSize++
+
+      return await next(args)
+    },
+    {
+      step: 'initialize',
+    }
+  )
+
+  return client
+}

src/index.mjs

@@ -1,6 +1,7 @@
 #!/usr/bin/env node
 import meow from 'meow'
-import { pullParameters, pushParameters } from './ssm.mjs'
+import { pullParameters } from './pull.mjs'
+import { pushParameters } from './push.mjs'
 import { toDotenvString } from './dotenv.mjs'
 
 const COMMANDS = {

src/pull.mjs

@@ -0,0 +1,29 @@
+import _ from 'lodash'
+import { paginateGetParametersByPath } from '@aws-sdk/client-ssm'
+import { createClient } from './client.mjs'
+
+export async function pullParameters({ client, prefix, ...config }) {
+  const paginator = paginateGetParametersByPath(
+    {
+      client: client ?? createClient(config),
+    },
+    {
+      Path: prefix,
+      Recursive: true,
+      WithDecryption: true,
+    }
+  )
+
+  const parameterList = []
+  for await (const page of paginator) {
+    parameterList.push(...page.Parameters)
+  }
+
+  return _.sortBy(parameterList, 'Name').reduce(
+    (parameters, { Name, Value }) => ({
+      ...parameters,
+      [Name.substr(prefix.length)]: Value,
+    }),
+    {}
+  )
+}

src/push.mjs

@@ -0,0 +1,87 @@
+import _ from 'lodash'
+import { PutParameterCommand, ParameterType } from '@aws-sdk/client-ssm'
+import { parseDotenv } from './dotenv.mjs'
+import { createClient, addThrottleMiddleware } from './client.mjs'
+import { pullParameters } from './pull.mjs'
+
+async function analyze({ client, prefix, file }) {
+  const parsedParameters = parseDotenv(file)
+
+  const remoteParameters = await pullParameters({ client, prefix })
+
+  let skipped = 0
+  let updated = 0
+  let created = 0
+
+  const parametersToUpdate = _.reduce(
+    parsedParameters,
+    (toUpdate, value, name) => {
+      if (_.has(remoteParameters, name)) {
+        if (remoteParameters[name] === value) {
+          skipped++
+        } else {
+          updated++
+          toUpdate[name] = value
+        }
+      } else {
+        created++
+        toUpdate[name] = value
+      }
+
+      return toUpdate
+    },
+    {}
+  )
+
+  return {
+    total: _.size(parsedParameters),
+    skipped,
+    updated,
+    created,
+    parameters: parametersToUpdate,
+  }
+}
+
+function printStat({ total, skipped, updated, created }) {
+  const padSize = _.max([skipped, updated, created]).toString().length
+
+  console.log(
+    [
+      `Total ${total} of parameters:`,
+      `  ${_.padStart(skipped, padSize)} up-to-date`,
+      `~ ${_.padStart(updated, padSize)} updated`,
+      `+ ${_.padStart(created, padSize)} created`,
+    ].join('\n')
+  )
+}
+
+/**
+ * Parameters are sent one by one with 1 second delay after each 10 requests to avoid `ThrottlingException: Rate exceeded`.
+ * See docs:
+ * https://aws.amazon.com/premiumsupport/knowledge-center/ssm-parameter-store-rate-exceeded/
+ * https://docs.aws.amazon.com/general/latest/gr/ssm.html#limits_ssm
+ */
+export async function pushParameters({ prefix, file, ...config }) {
+  const client = createClient(config)
+
+  const { parameters, ...stat } = await analyze({ client, prefix, file })
+
+  addThrottleMiddleware(client, { batchSize: 10, wait: 1000 })
+
+  const putCommands = _.map(
+    parameters,
+    (value, name) =>
+      new PutParameterCommand({
+        Type: ParameterType.STRING,
+        Overwrite: true,
+        Name: `${prefix}${name}`,
+        Value: value,
+      })
+  )
+
+  for (const putCommand of putCommands) {
+    await client.send(putCommand)
+  }
+
+  printStat(stat)
+}