Add basic LDAP bind functionality

app/unit/LDAPMiddlewareUnit.js

@@ -0,0 +1,41 @@
+const CanonicalUnit = require('libflitter/canon/CanonicalUnit')
+const LDAPMiddleware = require('../ldap/middleware/LDAPMiddleware')
+const StopError = require('libflitter/errors/StopError')
+
+class LDAPMiddlewareUnit extends CanonicalUnit {
+    static get services() {
+        return [...super.services, 'output']
+    }
+
+    static get name() {
+        return 'ldap_middleware'
+    }
+
+    constructor(base_directory = './app/ldap/middleware') {
+        super(base_directory)
+
+        this.canonical_item = 'ldap_middleware'
+        this.suffix = '.middleware.js'
+    }
+
+    async init_canonical_file({app, name, instance}) {
+        if ( instance.prototype instanceof LDAPMiddleware ) {
+            this.output.debug(`Registering LDAP middleware: ${name}`)
+            return new instance()
+        } else {
+            this.output.error(`LDAP middleware class ${name} must be an instance of LDAPMiddleware.`)
+            throw new StopError(`LDAP middleware class ${name} must be an instance of LDAPMiddleware.`)
+        }
+    }
+
+    get(name) {
+        const item = super.get(name)
+        if ( item instanceof LDAPMiddleware ) {
+            return item.test.bind(item)
+        }
+
+        return item
+    }
+}
+
+module.exports = exports = LDAPMiddlewareUnit