bcquality/microsoft/knowledge/security/isolatedstorage-datascope-module-vs-company.md

bc-version	domain	keywords	technologies	countries	application-area
24..	security	isolatedstorage datascope module company user scope	al	w1	all

Pick the right IsolatedStorage DataScope for the secret's lifetime

Description

IsolatedStorage read and write methods take a DataScope parameter that decides which slice of storage the value belongs to. The choice is not a stylistic one — it changes which callers, in which company and under which user, can read the value back. Two scopes cover the common cases for app-level secrets: DataScope::Module stores the value once for the whole extension, isolated to that extension on the tenant — the right scope for app-specific secrets such as a global API key or service account. DataScope::Company stores the value per company, so each company on the tenant has its own slot — the right scope for company-specific secrets such as a per-company webhook URL or a per-company integration token. A per-user scope also exists for values that belong to an individual user.

Best Practice

Choose Module when the secret is the same for every company and every user under the extension (a single tenant-wide API key). Choose Company when each company has its own integration credentials. Choose the user scope only when the secret is genuinely per-user. Use the same DataScope value on Set/SetEncrypted, Get, Contains, and Delete for the same key — mixing scopes for the same logical secret produces silent "not found" results. See sample: isolatedstorage-datascope-module-vs-company.good.al.

Anti Pattern

Defaulting every call to DataScope::Module regardless of intent — storing a per-company webhook URL under Module means every company on the tenant shares the same URL. Or the inverse: storing a tenant-wide API key under Company means each company-switch effectively loses the key. Reviewers should look for cross-method inconsistency (Set under Module, Get under Company) and for scope choices that contradict the value's documented lifetime. See sample: isolatedstorage-datascope-module-vs-company.bad.al.