Custom author component not working on Post Page

I suspect the issue is with 'page.context.message.uniqueId'. You can debug it by testing page.context.message for null etc.

Thanks, Nathan. I think you're probably right. 

So if I test  page.context.message for null, and it is null, then how would I pull the author information? Is there another call that would work better from the compose page?

I wonder how the native component does it...

So, since these REST API calls don't work from the Post Page, it seems I need to get the data in another way. Are there different REST API calls that would return the same data, and would work from the post page?

<#assign messageAuthorId = rest("/messages/id/${page.context.message.uniqueId}/author").user.id />
<#assign messageAuthorLogin = rest("/messages/id/${page.context.message.uniqueId}/author").user.login />
<#assign avatarUrl = rest("/users/id/${messageAuthorId}/profiles/avatar/url").value />
<#assign kudosCount = rest("/users/id/${messageAuthorId}/kudos/received/count").value />
<#assign postCount = rest("/users/id/${messageAuthorId}/posts/count").value />
<#assign rankingName = rest("users/id/${messageAuthorId}/ranking/name").value />
<#assign profileUrl = "/t5/user/viewprofilepage/user-id/${messageAuthorId}" />

Thoughts appreciated!

UPDATE: I added the Accepted Solutions metric to author component, so now it looks like this: http://screencast.com/t/y87ToDzd

In case anyone finds it useful, I thought I'd post the code here:

<#--Custom author component with new order: Avatar, rank, posts, kudos. Original author component XML is     <component id="author"/>. On Reply page, defaults to Out-of-the-box author component. Icons from FontAwesome icon set. -->

<style>

/* author stats */

#lia-body .lia-content .author-stats-row {
    text-align: center;
}

#lia-body .lia-content .author-stats-row .stat {
    display: inline-block;
    margin: 0 3px;
}

#lia-body .lia-content .fonticon i {
    -webkit-text-stroke: .5px;
    margin-bottom: 1px;
}

</style>

<#if page.name?lower_case == "replypage" >
    <@component id="author"/>
<#else>

<#assign messageAuthorId = env.context.message.author.id />
<#assign messageAuthorLogin = env.context.message.author.login />
<#assign avatarUrl = rest("/users/id/${messageAuthorId}/profiles/avatar/url").value />
<#assign kudosCount = rest("/users/id/${messageAuthorId}/kudos/received/count").value />
<#assign postCount = rest("/users/id/${messageAuthorId}/posts/count").value />
<#assign solutionsCount = rest("/users/id/${messageAuthorId}/solutions/received/count").value />
<#assign solutionsCountNumber = rest("/users/id/${messageAuthorId}/solutions/received/count") />
<#assign rankingName = rest("users/id/${messageAuthorId}/ranking/name").value />
<#assign profileUrl = "/t5/user/viewprofilepage/user-id/${messageAuthorId}" />

<div class="lia-message-author-avatar">    
    <div class="custom-avatar-wrapper">
        <div class="UserAvatar lia-user-avatar lia-component-common-widget-user-avatar">
            <a class="UserAvatar lia-link-navigation" tabindex="-1" target="_self" id="link_39" href="${profileUrl}"><img class="lia-user-avatar-message" id="display" src="${avatarUrl}"></a>
        </div>
             <#list restadmin("/users/id/${messageAuthorId}/roles").roles.role as role>
                <#if role.name?? && (role.name == "Premium")>
                     <img class="custom-avatar-overlay" alt="Premium User" title="Premium User" src="/html/assets/premium.png">
                </#if>
             </#list>
    </div>
</div>
<div class="lia-message-author-username">
    <span class="UserName lia-user-name">
        <a class="lia-link-navigation lia-page-link lia-user-name-link" href="${profileUrl}">
            <span class="">${messageAuthorLogin}</span>
        </a>
    </span>    
</div>
<div class="lia-message-author-rank">${rankingName}</div>

<div class="author-stats-row">
<#if (postCount?number > 0) >
    <div class="lia-message-author-post-count stat" title="${text.format('ranking.metric_posts.title')}">
                        <div class="count">${postCount}</div>
            <div class="fonticon"><i class="fa fa-comment"></i></div>
    </div>
</#if>
<#if (kudosCount?number > 0) >
   <div class="lia-message-author-kudos-count stat" title="${text.format('metrics.kudos_events_received.description')}">
            <div class="count">${kudosCount}</div>
                        <div class="fonticon"><i class="fa fa-thumbs-up"></i></div>
   </div>
</#if>
<#if (solutionsCount?number > 0) >
    <div class="lia-message-author-solutions-count stat" title="${text.format('analytics.columns.338.title')}">
                           <div class="count">${solutionsCount}</div>
                           <div class="fonticon"><i class="fa fa-check"></i></div>
    </div>
</#if>
</#if>
</div>