feat: add --no-service option for pbjs static target (#1577)

This option skips generation of service clients.

Co-authored-by: Alexander Fenster <fenster@google.com>

Author: mdouglass

cli/README.md

@@ -7,5 +7,168 @@ Command line interface (CLI) for [protobuf.js](https://github.com/dcodeIO/protob
 * [CLI Documentation](https://github.com/dcodeIO/protobuf.js#command-line)
 
 **Note** that moving the CLI to its own package is a work in progress. At the moment, it's still part of the main package.
+* [pbjs for JavaScript](#pbjs-for-javascript)
+* [pbts for TypeScript](#pbts-for-typescript)
+* [Reflection vs. static code](#reflection-vs-static-code)
+* [Command line API](#command-line-api)<br />
+
+### pbjs for JavaScript
+
+```
+Translates between file formats and generates static code.
+
+  -t, --target     Specifies the target format. Also accepts a path to require a custom target.
+
+                   json          JSON representation
+                   json-module   JSON representation as a module
+                   proto2        Protocol Buffers, Version 2
+                   proto3        Protocol Buffers, Version 3
+                   static        Static code without reflection (non-functional on its own)
+                   static-module Static code without reflection as a module
+
+  -p, --path       Adds a directory to the include path.
+
+  -o, --out        Saves to a file instead of writing to stdout.
+
+  --sparse         Exports only those types referenced from a main file (experimental).
+
+  Module targets only:
+
+  -w, --wrap       Specifies the wrapper to use. Also accepts a path to require a custom wrapper.
+
+                   default   Default wrapper supporting both CommonJS and AMD
+                   commonjs  CommonJS wrapper
+                   amd       AMD wrapper
+                   es6       ES6 wrapper (implies --es6)
+                   closure   A closure adding to protobuf.roots where protobuf is a global
+
+  -r, --root       Specifies an alternative protobuf.roots name.
+
+  -l, --lint       Linter configuration. Defaults to protobuf.js-compatible rules:
+
+                   eslint-disable block-scoped-var, no-redeclare, no-control-regex, no-prototype-builtins
+
+  --es6            Enables ES6 syntax (const/let instead of var)
+
+  Proto sources only:
+
+  --keep-case      Keeps field casing instead of converting to camel case.
+
+  Static targets only:
+
+  --no-create      Does not generate create functions used for reflection compatibility.
+  --no-encode      Does not generate encode functions.
+  --no-decode      Does not generate decode functions.
+  --no-verify      Does not generate verify functions.
+  --no-convert     Does not generate convert functions like from/toObject
+  --no-delimited   Does not generate delimited encode/decode functions.
+  --no-beautify    Does not beautify generated code.
+  --no-comments    Does not output any JSDoc comments.
+  --no-service     Does not output service classes.
+
+  --force-long     Enforces the use of 'Long' for s-/u-/int64 and s-/fixed64 fields.
+  --force-number   Enforces the use of 'number' for s-/u-/int64 and s-/fixed64 fields.
+  --force-message  Enforces the use of message instances instead of plain objects.
+
+usage: pbjs [options] file1.proto file2.json ...  (or pipe)  other | pbjs [options] -
+```
+
+For production environments it is recommended to bundle all your .proto files to a single .json file, which minimizes the number of network requests and avoids any parser overhead (hint: works with just the **light** library):
+
+```
+$> pbjs -t json file1.proto file2.proto > bundle.json
+```
+
+Now, either include this file in your final bundle:
+
+```js
+var root = protobuf.Root.fromJSON(require("./bundle.json"));
+```
+
+or load it the usual way:
+
+```js
+protobuf.load("bundle.json", function(err, root) {
+    ...
+});
+```
+
+Generated static code, on the other hand, works with just the **minimal** library. For example
+
+```
+$> pbjs -t static-module -w commonjs -o compiled.js file1.proto file2.proto
+```
+
+will generate static code for definitions within `file1.proto` and `file2.proto` to a CommonJS module `compiled.js`.
+
+**ProTip!** Documenting your .proto files with `/** ... */`-blocks or (trailing) `/// ...` lines translates to generated static code.
+
+
+### pbts for TypeScript
+
+```
+Generates TypeScript definitions from annotated JavaScript files.
+
+  -o, --out       Saves to a file instead of writing to stdout.
+
+  -g, --global    Name of the global object in browser environments, if any.
+
+  --no-comments   Does not output any JSDoc comments.
+
+  Internal flags:
+
+  -n, --name      Wraps everything in a module of the specified name.
+
+  -m, --main      Whether building the main library without any imports.
+
+usage: pbts [options] file1.js file2.js ...  (or)  other | pbts [options] -
+```
+
+Picking up on the example above, the following not only generates static code to a CommonJS module `compiled.js` but also its respective TypeScript definitions to `compiled.d.ts`:
+
+```
+$> pbjs -t static-module -w commonjs -o compiled.js file1.proto file2.proto
+$> pbts -o compiled.d.ts compiled.js
+```
+
+Additionally, TypeScript definitions of static modules are compatible with their reflection-based counterparts (i.e. as exported by JSON modules), as long as the following conditions are met:
+
+1. Instead of using `new SomeMessage(...)`, always use `SomeMessage.create(...)` because reflection objects do not provide a constructor.
+2. Types, services and enums must start with an uppercase letter to become available as properties of the reflected types as well (i.e. to be able to use `MyMessage.MyEnum` instead of `root.lookup("MyMessage.MyEnum")`).
+
+For example, the following generates a JSON module `bundle.js` and a `bundle.d.ts`, but no static code:
+
+```
+$> pbjs -t json-module -w commonjs -o bundle.js file1.proto file2.proto
+$> pbjs -t static-module file1.proto file2.proto | pbts -o bundle.d.ts -
+```
+
+### Reflection vs. static code
+
+While using .proto files directly requires the full library respectively pure reflection/JSON the light library, pretty much all code but the relatively short descriptors is shared.
+
+Static code, on the other hand, requires just the minimal library, but generates additional source code without any reflection features. This also implies that there is a break-even point where statically generated code becomes larger than descriptor-based code once the amount of code generated exceeds the size of the full respectively light library.
+
+There is no significant difference performance-wise as the code generated statically is pretty much the same as generated at runtime and both are largely interchangeable as seen in the previous section.
+
+| Source | Library | Advantages | Tradeoffs
+|--------|---------|------------|-----------
+| .proto | full    | Easily editable<br />Interoperability with other libraries<br />No compile step | Some parsing and possibly network overhead
+| JSON   | light   | Easily editable<br />No parsing overhead<br />Single bundle (no network overhead) | protobuf.js specific<br />Has a compile step
+| static | minimal | Works where `eval` access is restricted<br />Fully documented<br />Small footprint for small protos | Can be hard to edit<br />No reflection<br />Has a compile step
+
+### Command line API
+
+Both utilities can be used programmatically by providing command line arguments and a callback to their respective `main` functions:
+
+```js
+var pbjs = require("protobufjs-cli/pbjs"); // or require("protobufjs-cli").pbjs / .pbts
+
+pbjs.main([ "--target", "json-module", "path/to/myproto.proto" ], function(err, output) {
+    if (err)
+        throw err;
+    // do something with output
+});
+```
 
 **License:** [BSD 3-Clause License](https://opensource.org/licenses/BSD-3-Clause)

cli/pbjs.js

@@ -44,7 +44,7 @@ exports.main = function main(args, callback) {
             "force-message": "strict-message"
         },
         string: [ "target", "out", "path", "wrap", "dependency", "root", "lint" ],
-        boolean: [ "create", "encode", "decode", "verify", "convert", "delimited", "beautify", "comments", "es6", "sparse", "keep-case", "force-long", "force-number", "force-enum-string", "force-message" ],
+        boolean: [ "create", "encode", "decode", "verify", "convert", "delimited", "beautify", "comments", "service", "es6", "sparse", "keep-case", "force-long", "force-number", "force-enum-string", "force-message" ],
         default: {
             target: "json",
             create: true,
@@ -55,6 +55,7 @@ exports.main = function main(args, callback) {
             delimited: true,
             beautify: true,
             comments: true,
+            service: true,
             es6: null,
             lint: lintDefault,
             "keep-case": false,
@@ -135,6 +136,7 @@ exports.main = function main(args, callback) {
                 "  --no-delimited   Does not generate delimited encode/decode functions.",
                 "  --no-beautify    Does not beautify generated code.",
                 "  --no-comments    Does not output any JSDoc comments.",
+                "  --no-service     Does not output service classes.",
                 "",
                 "  --force-long     Enfores the use of 'Long' for s-/u-/int64 and s-/fixed64 fields.",
                 "  --force-number   Enfores the use of 'number' for s-/u-/int64 and s-/fixed64 fields.",

cli/targets/static.js

@@ -109,6 +109,10 @@ function aOrAn(name) {
 function buildNamespace(ref, ns) {
     if (!ns)
         return;
+
+    if (ns instanceof Service && !config.service)
+        return;
+
     if (ns.name !== "") {
         push("");
         if (!ref && config.es6)