add conversations.join method (#234)

lib/slack/web/docs/conversations.join.json

@@ -0,0 +1,43 @@
+{
+  "desc": "Joins an existing conversation",
+
+  "args": {
+    "channel": {
+      "example": "C1234567890",
+      "required": true,
+      "desc": "ID of conversation to join"
+    }
+  },
+
+  "errors": {
+    "channel_not_found": "Value passed for `channel` was invalid.",
+    "is_archived": "Channel has been archived.",
+    "method_not_supported_for_channel_type": "This type of conversation cannot be used with this method.",
+    "missing_scope": "The token used is not granted the specific scope permissions required to complete this request.",
+    "too_many_members": "The membership in the channel has exceeded our maximum member limit. No more users can join the channel.",
+    "not_authed": "No authentication token provided.",
+    "invalid_auth": "Some aspect of authentication cannot be validated. Either the provided token is invalid or the request originates from an IP address disallowed from making the request.",
+    "account_inactive": "Authentication token is for a deleted user or workspace.",
+    "token_revoked": "Authentication token is for a deleted user or workspace or the app has been removed.",
+    "no_permission": "The workspace token used in this request does not have the permissions necessary to complete the request. Make sure your app is a member of the conversation it's attempting to post a message to.",
+    "org_login_required": "The workspace is undergoing an enterprise migration and will not be available until migration is complete.",
+    "ekm_access_denied": "Administrators have suspended the ability to post a message.",
+    "not_allowed_token_type": "The token type used in this request is not allowed.",
+    "method_deprecated": "The method has been deprecated.",
+    "deprecated_endpoint": "The endpoint has been deprecated.",
+    "is_bot": "This method cannot be called by a bot user.",
+    "user_is_restricted": "This method cannot be called by a restricted user or single channel guest.",
+    "invalid_arguments": "The method was either called with invalid arguments or some detail about the arguments passed are invalid, which is more likely when using complex arguments like blocks or attachments.",
+    "invalid_arg_name": "The method was passed an argument whose name falls outside the bounds of accepted or expected values. This includes very long names and names with non-alphanumeric characters other than `_`. If you get this error, it is typically an indication that you have made a very malformed API call.",
+    "invalid_charset": "The method was called via a `POST` request, but the charset specified in the `Content-Type` header was invalid. Valid charset names are: `utf-8` `iso-8859-1`.",
+    "invalid_form_data": "The method was called via a `POST` request with `Content-Type` `application/x-www-form-urlencoded` or `multipart/form-data`, but the form data was either missing or syntactically invalid.",
+    "invalid_post_type": "The method was called via a `POST` request, but the specified `Content-Type` was invalid. Valid types are: `application/json` `application/x-www-form-urlencoded` `multipart/form-data` `text/plain`.",
+    "missing_post_type": "The method was called via a `POST` request and included a data payload, but the request did not include a `Content-Type` header.",
+    "team_added_to_org": "The workspace associated with your request is currently undergoing migration to an Enterprise Organization. Web API and other platform operations will be intermittently unavailable until the transition is complete.",
+    "ratelimited": "The request has been ratelimited. Refer to the `Retry-After` header for when to retry the request.",
+    "request_timeout": "The method was called via a `POST` request, but the `POST` data was either missing or truncated.",
+    "service_unavailable": "The service is temporarily unavailable",
+    "fatal_error": "The server could not complete your operation(s) without encountering a catastrophic error. It's possible some aspect of the operation succeeded before the error was raised.",
+    "internal_error": "The server could not complete your operation(s) without encountering an error, likely due to a transient issue on our end. It's possible some aspect of the operation succeeded before the error was raised."
+  }
+}