Merge pull request #174 from Shopify/ah.input-flag

Use an argument for JSON input

src/main.rs

@@ -5,7 +5,7 @@ use std::{
 };
 
 use anyhow::{anyhow, Result};
-use clap::{CommandFactory, Parser};
+use clap::Parser;
 use function_runner::engine::{run, ProfileOpts};
 
 use is_terminal::IsTerminal;
@@ -22,6 +22,7 @@ struct Opts {
  function: PathBuf,
 
  /// Path to json file containing Function input; if omitted, stdin is used
+ #[clap(short, long)]
  input: Option<PathBuf>,
 
  /// Name of the export to invoke.
@@ -86,10 +87,9 @@ fn main() -> Result<()> {
  } else if !std::io::stdin().is_terminal() {
  Box::new(BufReader::new(stdin()))
  } else {
- Opts::command()
- .print_help()
- .expect("Printing help should not fail");
- return Ok(());
+ return Err(anyhow!(
+ "You must provide input via the --input flag or piped via stdin."
+ ));
  };
 
  let mut buffer = Vec::new();

tests/integration_tests.rs

@@ -15,9 +15,8 @@ mod tests {
  fn run() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
- .arg("benchmark/build/volume_discount.json");
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"])
+ .args(["--input", "benchmark/build/volume_discount.json"]);
  cmd.assert().success();
 
  Ok(())
@@ -27,10 +26,9 @@ mod tests {
  fn invalid_json_input() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"])
  .arg("--json")
- .arg("benchmark/build/invalid_json.json");
+ .args(["--input", "benchmark/build/invalid_json.json"]);
  cmd.assert()
  .failure()
  .stderr("Error: Invalid input JSON: EOF while parsing an object at line 2 column 0\n");
@@ -43,8 +41,7 @@ mod tests {
  let file = File::open("benchmark/build/volume_discount.json")?;
  let mut cmd = Command::cargo_bin("function-runner")?;
  let output = cmd
- .arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
+ .args(["--function", "benchmark/build/runtime_function.wasm"])
  .arg("--json")
  .stdin(Stdio::from(file))
  .stdout(Stdio::piped())
@@ -85,22 +82,11 @@ mod tests {
  #[ignore = "This test hangs on CI but runs locally, is_terminal is likely returning false in CI"]
  fn run_function_no_input() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
- let output = cmd
- .arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
- .stdout(Stdio::piped())
- .spawn()
- .expect("Failed to spawn child process")
- .wait_with_output()
- .expect("Failed waiting for output");
 
- let actual = String::from_utf8(output.stdout).unwrap();
- let predicate = predicate::str::contains(
- "Simple Function runner which takes JSON as a convenience\n\nUsage: function-runner",
- )
- .count(1);
-
- assert!(predicate.eval(&actual));
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"]);
+ cmd.assert()
+ .failure()
+ .stderr("Error: You must provide input via the --input flag or piped via stdin.\n");
 
  Ok(())
  }
@@ -109,10 +95,9 @@ mod tests {
  fn run_json() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"])
  .arg("--json")
- .arg("benchmark/build/volume_discount.json");
+ .args(["--input", "benchmark/build/volume_discount.json"]);
  cmd.assert().success();
  let output = cmd.output().expect("Wasn't able to get output");
  let _ = serde_json::from_slice::<FunctionRunResult>(&output.stdout)
@@ -125,9 +110,8 @@ mod tests {
  fn wasm_file_doesnt_exist() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("test/file/doesnt/exist")
- .arg("benchmark/build/volume_discount.json");
+ cmd.args(["--function", "test/file/doesnt/exist"])
+ .args(["--input", "benchmark/build/volume_discount.json"]);
  cmd.assert()
  .failure()
  .stderr("Error: Couldn\'t load the Function \"test/file/doesnt/exist\": failed to read input file\n");
@@ -139,9 +123,8 @@ mod tests {
  fn input_file_doesnt_exist() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
- .arg("test/file/doesnt/exist.json");
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"])
+ .args(["--input", "test/file/doesnt/exist.json"]);
  cmd.assert()
  .failure()
  .stderr("Error: Couldn\'t load input \"test/file/doesnt/exist.json\": No such file or directory (os error 2)\n");
@@ -184,9 +167,8 @@ mod tests {
  fn incorrect_input() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
 
- cmd.arg("--function")
- .arg("benchmark/build/runtime_function.wasm")
- .arg("benchmark/build/product_discount.json");
+ cmd.args(["--function", "benchmark/build/runtime_function.wasm"])
+ .args(["--input", "benchmark/build/product_discount.json"]);
  cmd.assert()
  .success()
  .stdout(contains("missing field `discountNode`"))
@@ -202,7 +184,7 @@ mod tests {
  let mut cmd = Command::cargo_bin("function-runner")?;
  cmd.args(["--function", "benchmark/build/exports.wasm"])
  .args(["--export", "export1"])
- .arg("benchmark/build/product_discount.json");
+ .args(["--input", "benchmark/build/product_discount.json"]);
 
  cmd.assert().success().stdout(contains("export1"));
 
@@ -213,7 +195,7 @@ mod tests {
  fn missing_export() -> Result<(), Box<dyn std::error::Error>> {
  let mut cmd = Command::cargo_bin("function-runner")?;
  cmd.args(["--function", "benchmark/build/exports.wasm"])
- .arg("benchmark/build/product_discount.json");
+ .args(["--input", "benchmark/build/product_discount.json"]);
 
  cmd.assert()
  .failure()
@@ -231,6 +213,7 @@ mod tests {
  cmd.current_dir(temp.path())
  .arg("--function")
  .arg(cwd.join("benchmark/build/runtime_function.wasm"))
+ .arg("--input")
  .arg(cwd.join("benchmark/build/volume_discount.json"));
 
  Ok((cmd, temp))