Mini program white-label build guide

Build packages for multiple brands from the same app/ codebase: brand name, theme color, backend domain, appid and icons all come from build parameters — switching merchants means passing different parameters, with no code changes and no extra branches.

Collect these parameters from the merchant first

Parameter	CLI flag	Notes	Example
Brand name	--name	Mini program name, navigation bar title, H5 page title	和济堂
Backend domain	--domain	Server address, must be https	https://api.hejitang.example.com
Theme color	--theme	#RGB or #RRGGBB; primary color for nav bar / buttons / self-check page	#8C1F28
Mini program appid	--appid	The appid registered on the WeChat platform, 16 characters starting with wx	wx1a2b3c4d5e6f7a8b
Icon	--icon	Only files supplied by the merchant are accepted — no stand-ins of any kind	/path/hejitang-icon.png
Description text	--desc	H5 page description only	和济堂中医馆线上服务
Build target	--target	weapp (default) or h5	weapp

With no parameters you get the default package (Sinomed / #C7A674 / https://sinomed.cuihairu.site / touristappid).

One-command build

cd app
node scripts/build-brand.mjs \
  --name 和济堂 \
  --domain https://api.hejitang.example.com \
  --theme '#8C1F28' \
  --appid wx1a2b3c4d5e6f7a8b \
  --icon /path/hejitang-icon.png \
  --target weapp

Output goes to app/dist/; import it into the WeChat DevTools to preview.

What the script does: parameter validation (theme-color format, appid format, domain scheme, icon file existence) → inject environment variables → taro build → restore the appid in the repo-root project.config.json. Invalid parameters fail loudly and exit; you never get a package built with wrong parameters.

For an H5 package, change --target to h5; the brand name / icon / theme color then go into the page title, favicon and meta tags.

Two verified parameter sets

Both command sets below were actually run and the output verified:

Default package

node scripts/build-brand.mjs

Verified: dist/project.config.json appid is touristappid; dist/app.json navigation bar is Sinomed / #C7A674; no merchant residue anywhere in the output.

Sample merchant package (和济堂)

node scripts/build-brand.mjs \
  --name 和济堂 \
  --domain https://api.hejitang.example.com \
  --theme '#8C1F28' \
  --appid wx1a2b3c4d5e6f7a8b \
  --icon /tmp/hejitang/icon.png

Verified: dist/project.config.json appid is wx1a2b3c4d5e6f7a8b; dist/app.json navigation bar is 和济堂 / #8C1F28; the icon is injected into the in-page self-check area as base64; after the build the repo-root project.config.json is restored to touristappid and the git worktree is clean.

In-package self check: build with --diag and the "white-label build parameter self-check page" appears on the app's 我的 tab, where all four values — brand name, theme color, backend domain and in-page icon — are visible directly. Check that page first after every acceptance build; the parameters are right or wrong at a glance. Without --diag the panel is not bundled, so it never reaches end customers.

Icon policy

• Only files supplied by the merchant. app/brand-assets/ in the repo holds only the default assets; a merchant icon is never copied in, renamed, recolored or otherwise "processed".
• Pass a png/jpg bitmap: injected into both the H5 favicon and the in-page mini-program icon.
• Pass an svg: only the H5 favicon is injected; the in-page mini-program icon is left empty and the build prints a note (the mini-program <Image> component does not accept svg, and no substitute image is swapped in).
• The mini-program avatar inside WeChat is uploaded in the WeChat platform console and has nothing to do with this script — the script cannot change what the WeChat platform stores.

Troubleshooting

Theme color / brand did not take effect? Rebuild with --diag and open the self-check page to look at the four values. If they are still wrong, the parameter most likely failed validation (the build fails loudly in that case), or you ran a bare pnpm build:weapp and bypassed the script — always build merchant packages through build-brand.mjs.

404s after changing the domain? Confirm the server is actually deployed at that domain and exposes the /api/v1 prefix; for local debugging the domain can be http://localhost:8080.

Wrong appid? The appid is written into dist/project.config.json at build time and validated when the WeChat DevTools imports dist. Fix the parameter and rebuild; the repo's project.config.json is restored automatically after every build, so no merchant appid ever lingers.