MS Outlook – Attachments – Get Attachments

Get Outlook message attachments. Uses the selected mailbox and returns the available result.

Collects attachment results while following the mapped @odata.nextLink until it is blank. Top Query controls the request page size rather than a guaranteed total result limit. Multiple pages consume callouts and heap. Attachment types can differ; file bytes are not guaranteed for every item.

Action details

Property	Value
Action label	MS Outlook – Attachments – Get Attachments
Category	CloudTools
Apex class and method	GetMSOutlookAttachments.getAttachments
Input type	GetMSOutlookAttachments.GetMSOutlookAttachmentsInput
Output type	List<List<MSOutlookAttachment>>
Authorization	OAuth Delegated (Authorization Code) or OAuth Application (Client Credentials).
Flow automation	Use an application connector configured as the Flow default.
Microsoft Graph operation	GET /v1.0/me/messages/{messageId}/attachments for Authorization Code Flow; otherwise GET /v1.0/users/{userIdOrPrincipalName}/messages/{messageId}/attachments.

Prerequisites and permissions

Configure a CloudTools Connector with Connector Type set to Microsoft 365. Complete Microsoft sign-in for delegated access. For application access, grant application permissions and administrator consent, supply the target mailbox user ID or principal name, and ensure the app can access that mailbox.

Microsoft requires Mail.Read for delegated and application access. Mail.ReadWrite is also supported. See the Microsoft operation and permissions reference.

Mailbox selection: Authorization Code Flow uses /me and ignores userIdOrPrincipalName. Supplying another user does not redirect that call. Other authorization types use /users/{userIdOrPrincipalName}; their authentication must be valid for Microsoft Graph. Use Graph resource IDs rather than Salesforce record IDs.

Inputs

The table lists action labels, Apex field names, and data types. Provide one non-null request per invocation. Required text must not be blank.

Input	Apex field	Type	Required	Description
User Id or Principal Name	userIdOrPrincipalName	String	Unless Authorization Code Flow is enabled	User id or user principal name. Required for application authorization; ignored for Authorization Code Flow.
Message Id	messageId	String	Yes	Message identifier.
Select Query	selectQuery	String	No	OData select query. Supply the value only, without a prefix such as $select= or a full URL. Microsoft validates query support.
Top Query	topQuery	String	No	OData top query. Supply the value only, without a prefix such as $select= or a full URL. Microsoft validates query support.

The invocable input has no connectorId field. Apex and Flow use CloudTools connector selection; the LWC controller accepts an additional connectorId property to select a record. This action does not resolve replacement tokens in its inputs; resolve dynamic values first. See Using Token Replacements.

Outputs

The invocable method returns List<List<MSOutlookAttachment>>: one outer result containing the collection for the first request. Read the inner list in Apex; Flow receives a collection output. An empty lookup produces an empty inner list. The JavaScript wrapper returns a flat array.

This action follows attachment continuation links and combines pages.

Output	Apex field	Type	Description
Id	id	String	Attachment identifier.
Name	name	String	Attachment name.
Content Type	contentType	String	Attachment MIME content type.
Size	size	Long	Attachment size in bytes.
Is Inline	isInline	Boolean	Whether attachment is inline.
Last Modified Date Time	lastModifiedDateTime	String	Last modified timestamp.
Content Id	contentId	String	Attachment content id.
Content Location	contentLocation	String	Attachment content location.
Content Bytes	contentBytes	String	Base64-encoded content.
OData Type	odataType	String	OData type.
Additional Properties	additionalProperties	List<DynamicObject>	Additional data returned by query.

Optional properties depend on the response and any Select or Expand query. Do not treat an absent field as proof of its value. Timestamps represented by String remain text. Counts and metadata do not contain the full contents of the resource.

Use in Flow

Add MS Outlook – Attachments – Get Attachments in Flow Builder. Configure a Microsoft 365 application connector as the default for Flow automations, then populate the inputs above. Delegated connectors are not supported for CloudTools Flow automation. Add a fault path for callout errors. This implementation processes only the first input request; it is not a bulk action.

Use in custom Apex

This subscriber-org example uses the Apptigent namespace. Replace placeholders before use. Run in a context that permits callouts with a configured application connector. For an already-authorized delegated connector, omit the user value.

Apptigent.GetMSOutlookAttachments.GetMSOutlookAttachmentsInput request =
    new Apptigent.GetMSOutlookAttachments.GetMSOutlookAttachmentsInput();
request.userIdOrPrincipalName = 'REPLACE_WITH_MICROSOFT_USER_ID_OR_UPN';
request.messageId = 'REPLACE_WITH_MESSAGE_ID';

List<List<Apptigent.MSOutlookAttachment>> results =
    Apptigent.GetMSOutlookAttachments.getAttachments(
        new List<Apptigent.GetMSOutlookAttachments.GetMSOutlookAttachmentsInput>{ request }
    );

List<Apptigent.MSOutlookAttachment> items = results.isEmpty()
    ? new List<Apptigent.MSOutlookAttachment>() : results[0];
System.debug(items.size());

Submit one request per invocation. The example does not implement connector setup, delegated sign-in, or exception handling; those belong in the calling application.

Use in a Lightning Web Component

Use getMSOutlookAttachments from msOutlookConnectorLib, through MSOutlookConnectorController. This example uses repository c/ imports for a component in the same namespace. Replace placeholders and complete connector authorization before invoking it.

outlookActionExample.js

import { LightningElement } from 'lwc';
import { getMSOutlookAttachments, MSOutlookObjects } from 'c/msOutlookConnectorLib';

export default class OutlookActionExample extends LightningElement {
    connectorId = 'REPLACE_WITH_CONNECTOR_RECORD_ID';
    result = null;
    errorMessage = '';
    isRunning = false;
    completed = false;

    async handleRun() {
        if (this.isRunning) {
            return;
        }
        this.isRunning = true;
        this.errorMessage = '';
        try {
            const request = MSOutlookObjects.inputs.attachment();
            request.connectorId = this.connectorId;
            request.userIdOrPrincipalName = 'REPLACE_WITH_MICROSOFT_USER_ID_OR_UPN';
            request.messageId = 'REPLACE_WITH_MESSAGE_ID';
            const result = await getMSOutlookAttachments(request);
            if (!Array.isArray(result)) {
                throw new Error('No collection result was returned.');
            }
            this.result = result;
            this.completed = true;
        } catch (error) {
            this.errorMessage = error.requiresInteractiveAuthorization
                ? 'Sign in to Microsoft for this connector, then try again.'
                : error.message || 'The Outlook action failed.';
        } finally {
            this.isRunning = false;
        }
    }
}

outlookActionExample.html

<template>
    <lightning-button label="Run action" onclick={handleRun}
        disabled={isRunning}></lightning-button>
    <p role="alert">{errorMessage}</p>
</template>

The library accepts one request object and resolves to a flat array of items; use result.length and iterate the array, without an outer Apex list. The shared factory includes inputs for other actions; only the fields in this page and optional connectorId are used here.

The controller also exposes rawJson as a serialization of the mapped Apex result; it is not an original Microsoft response or an invocable Flow output.

This example reports authorization errors but does not implement sign-in. For delegated access, use getMSOutlookAuthorizationState, beginMSOutlookAuthorization, and createMSOutlookOAuthMessageHandler. Errors expose message and requiresInteractiveAuthorization.

Error handling and troubleshooting

Symptom	What to check
Required fields error	Pass a nonempty list with a non-null first request. Populate required resource fields and User Id or Principal Name for application authorization.
Authorization is required	Complete or renew the current user’s delegated Microsoft authorization for the selected connector.
Access denied	Check the operation permission, consent, connector identity, and mailbox access.
Resource not found	Verify IDs belong to the selected mailbox and refer to the expected resource. Authorization Code Flow ignores the user input.
Query rejected	Supply only supported OData values. Simplify Select, Expand, Filter, and Order By queries and review the Microsoft reference.
Unexpected result	Check for an empty Apex result, a null JavaScript response, omitted properties, or incomplete pagination. Handle exceptions in the caller.