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Portal guide

As of

The As of page shows a namespace's whole state as it stood at a CSN or a time, read as one of your keys.

What this page is for#

The As of page (/asof) reads a namespace as it stood at an earlier moment and shows the whole state as TERSL text. You name the moment by its CSN (change sequence number) or by a time, and the page says which CSN the service served. Use it to see what a namespace held before a change, or to check a value at a point you found on History. The page is not in the left menu; open it at /asof.

Who can see it#

Every signed-in user who holds a key that some active namespace grants. The state shown is pruned to what the chosen key may see under its history right, as the grants stand now. A key that has read but not history sees an empty state.

What is on the page#

The form#

The form has Namespace and Key (see the namespace and key pickers), a CSN field, and or a time, a date-and-time field in your local time. Press Read to load the state. The key picker's caption reads "The state is pruned to what this key may see under its history grant, as the grants stand now."

If nothing can be read, the page says why: you have no key to read with, or no key you hold reaches the chosen namespace.

The answer line#

After a read, a line names the Namespace, the key and what you asked, then "served as of csn N", the CSN the state was read at. When the namespace's record is chained, the line also shows the start of a receipt: the chain value of the step at that CSN, which ties the answer to that exact point in the record. Hover over it to see it whole.

A time typed without a time zone (for example, with JavaScript off) is read as UTC, and the line says "(read as UTC: no time zone came with it)".

The state#

Below the line, the namespace's state at that moment is shown as TERSL text. Any messages the service returned are shown under it. If the service refused the read, the page says "The service answered" followed by the status and its message.

Actions#

Read the namespace at a CSN#

Choose a namespace and key, type a CSN and press Read. A CSN past the newest step is read as the newest.

Read the namespace at a time#

Fill or a time instead and press Read. The service reads the newest step committed at or before that time, and the answer line says which CSN that was. A time before the namespace's first step is refused with a 422 that says the first entry is csn 1.

What is read-only#

Everything on this page is a read. The past cannot be written: to work from an earlier state, make a copy of the namespace at that moment, which is a new namespace you can change. To run your own queries at a moment rather than read the whole state, open the Explorer at that CSN with Query at this step on History.