Wait for command to execute, add intro to help message

Author: codetheweb

src/cli/browser.ts

@@ -14,22 +14,61 @@ type CLIEvents = {
 class BrowserCLI extends (EventEmitter as unknown as new () => TypedEmitter<CLIEvents>) {
   private instance = getCLI(yargsInstance).scriptName("seam")
 
+  /**
+   * Use the Seam CLI in the browser!
+   */
   constructor(private apiKey?: string) {
     super()
     this.setUpShims()
   }
 
-  async parse(...args: Parameters<typeof yargsInstance.parse>) {
+  /**
+   * Parse a command line string. Output will be emitted as data events.
+   * @param input a given command string
+   * @example
+   * ```
+   * const cli = new BrowserCLI()
+   * await cli.parse("seam --help")
+   * ```
+   */
+  async parse(input: string) {
     this.setUpShims()
 
-    const [input] = args
     const inputWithKey = input.includes("--api-key")
       ? input
       : `${input} --api-key ${this.apiKey}`
 
-    await this.instance.parse(inputWithKey, ...(args.slice(1) as any))
+    await new Promise<void>((resolve, reject) => {
+      // .parseAsync isn't available in v16, so we listen for the ending newline instead
+      const onData = (data: string) => {
+        if (data === "\n") {
+          this.removeListener("data", onData)
+          resolve()
+        }
+      }
+      this.on("data", onData)
+
+      this.instance.parse(
+        inputWithKey,
+        (error: Error, _argv: any, output?: string) => {
+          if (error) {
+            this.removeListener("data", onData)
+            return reject(error)
+          }
+
+          if (output) {
+            this.emit("data", output)
+            this.emit("data", "\n")
+          }
+        }
+      )
+    })
   }
 
+  /**
+   * Set the wrap value of the Yargs instance
+   * @param columns number of columns to wrap to
+   */
   setWidth(columns: number) {
     this.instance = this.instance.wrap(columns)
   }

src/cli/index.ts

@@ -10,7 +10,12 @@ export const getCLI = (yargs: Argv) => {
     builder = builder.command(command.default as any)
   }
 
-  builder = builder.demandCommand().strict()
+  builder = builder
+    .demandCommand()
+    .strict()
+    .usage(
+      "Control locks, lights and other internet of things devices with Seam's simple API."
+    )
 
   return builder
 }