address comments: better naming and tsdoc

src/AzureAppConfigurationImpl.ts

@@ -46,7 +46,7 @@ export class AzureAppConfigurationImpl extends Map<string, unknown> implements A
         const keyValues: [key: string, value: unknown][] = [];
 
         // validate selectors
-        const selectors = validatedSelectors(this.options?.selectors);
+        const selectors = getValidSelectors(this.options?.selectors);
 
         for (const selector of selectors) {
             const listOptions: ListConfigurationSettingsOptions = {
@@ -109,15 +109,15 @@ export class AzureAppConfigurationImpl extends Map<string, unknown> implements A
     }
 }
 
-function validatedSelectors(selectors?: { keyFilter: string, labelFilter?: string }[]) {
+function getValidSelectors(selectors?: { keyFilter: string, labelFilter?: string }[]) {
     if (!selectors || selectors.length === 0) {
         // Default selector: key: *, label: \0
         return [{ keyFilter: KeyFilter.Any, labelFilter: LabelFilter.Null }];
     }
     return selectors.map(selectorCandidate => {
         const selector = { ...selectorCandidate };
         if (!selector.keyFilter) {
-            throw new Error("Key filters cannot be empty.");
+            throw new Error("Key filter cannot be null or empty.");
         }
         if (!selector.labelFilter) {
             selector.labelFilter = LabelFilter.Null;

src/AzureAppConfigurationOptions.ts

@@ -9,10 +9,23 @@ export const MaxRetryDelayInMs = 60000;
 
 export interface AzureAppConfigurationOptions {
     /**
-     * Selectors used to control what key-values are retrieved from Azure App Configuration.
+     * Specify what key-values to include in the configuration provider.  include multiple sets of key-values
      *
-     * @property keyFilter: A filter that determines the set of keys that are included in the configuration provider, cannot be omitted.
-     * @property labelFilter: A filter that determines what label to use when selecting key-values for the the configuration provider, omitted for no label.
+     * @property keyFilter:
+     * The key filter to apply when querying Azure App Configuration for key-values.
+     * An asterisk `*` can be added to the end to return all key-values whose key begins with the key filter.
+     * e.g. key filter `abc*` returns all key-values whose key starts with `abc`.
+     * A comma `,` can be used to select multiple key-values. Comma separated filters must exactly match a key to select it.
+     * Using asterisk to select key-values that begin with a key filter while simultaneously using comma separated key filters is not supported.
+     * E.g. the key filter `abc*,def` is not supported. The key filters `abc*` and `abc,def` are supported.
+     * For all other cases the characters: asterisk `*`, comma `,`, and backslash `\` are reserved. Reserved characters must be escaped using a backslash (\).
+     * e.g. the key filter `a\\b\,\*c*` returns all key-values whose key starts with `a\b,*c`.
+     *
+     * @property labelFilter:
+     * The label filter to apply when querying Azure App Configuration for key-values.
+     * By default, the "null label" will be used, matching key-values without a label.
+     * The characters asterisk `*` and comma `,` are not supported.
+     * Backslash `\` character is reserved and must be escaped using another backslash `\`.
      */
     selectors?: { keyFilter: string, labelFilter?: string }[];
     trimKeyPrefixes?: string[];