docs(clp-package): Rewrite S3 log compression guide to reflect new API and script features.

docs/src/user-docs/guides-using-object-storage/clp-usage.md

@@ -5,35 +5,97 @@ should be able to use CLP as described in the [clp-json quick-start guide](../qu
 
 ## Compressing logs from S3
 
-To compress logs from S3, use the `sbin/compress.sh` script as follows, replacing the fields in
-angle brackets (`<>`) with the appropriate values:
+To compress logs from S3, use the `sbin/compress-from-s3.sh` script. The script supports two modes
+of operation:
+
+* [**s3-object** mode](#s3-object-compression-mode): Compress S3 objects specified by their full
+  S3 URLs.
+* [**s3-key-prefix** mode](#s3-key-prefix-compression-mode): Compress all S3 objects under a given
+  S3 key prefix.
+
+### `s3-object` compression mode
+
+The `s3-object` mode allows you to specify individual S3 objects to compress by using their full
+URLs. To use this mode, call the `sbin/compress-from-s3.sh` script as follows, and replace the
+fields in angle brackets (`<>`) with the appropriate values:
 
 ```bash
-sbin/compress.sh \
+sbin/compress-from-s3.sh \
   --timestamp-key <timestamp-key> \
-  <url>
+  --dataset <dataset-name> \
+  s3-object \
+  <object-url> [<object-url> ...]
 ```
 
-* `<url>` is a URL identifying the logs to compress. It can have one of two formats:
-  * `https://<bucket-name>.s3.<region-code>.amazonaws.com/<prefix>`
-  * `https://s3.<region-code>.amazonaws.com/<bucket-name>/<prefix>`
-* The fields in `<url>` are as follows:
+* `<object-url>` is a URL identifying the S3 object to compress. It can be written in either of two
+  formats:
+  * `https://<bucket-name>.s3.<region-code>.amazonaws.com/<object-key>`
+  * `https://s3.<region-code>.amazonaws.com/<bucket-name>/<object-key>`
+* The fields in `<object-url>` are as follows:
   * `<bucket-name>` is the name of the S3 bucket containing your logs.
   * `<region-code>` is the AWS region [code][aws-region-codes] for the S3 bucket containing your
     logs.
-  * `<prefix>` is the prefix of all logs you wish to compress and must begin with the
-    `<all-logs-prefix>` value from the [compression IAM policy][compression-iam-policy].
+  * `<object-key>` is the [object key][aws-s3-object-key] of the log file object you wish to
+    compress.
+
+    :::{warning}
+    There must be no duplicate object keys across all `<object-url>` arguments.
+    :::
+
+
+* For a description of other fields, see the [clp-json quick-start
+  guide](../quick-start/clp-json.md#compressing-json-logs).
+
+Instead of specifying input object URLs explicitly in the command, you may specify them in a text
+file and then pass the file into the command using the `--inputs-from` flag, like so:
+
+```bash
+sbin/compress-from-s3.sh \
+  --timestamp-key <timestamp-key> \
+  --dataset <dataset-name> \
+  s3-object \
+  --inputs-from <input-file>
+```
+
+* `<input-file>` is a path to a text file containing one S3 object URL **per line**. The URLs must
+  follow the same format as described above for `<object-url>`.
 
 :::{note}
-Compressing from S3 only supports a single URL but will compress any logs that have the given
-prefix.
+The `s3-object` mode requires the input object keys to share a non-empty common prefix. If the input
+object keys do not share a common prefix, they will be rejected and no compression job will be
+created. This limitation will be addressed in a future release.
+:::
+
+### `s3-key-prefix` compression mode
+
+The `s3-key-prefix` mode allows you to compress all objects under a given S3 key prefix. To use this
+mode, call the `sbin/compress-from-s3.sh` script as follows, and replace the fields in angle
+brackets (`<>`) with the appropriate values:
+
+```bash
+sbin/compress-from-s3.sh \
+  --timestamp-key <timestamp-key> \
+  --dataset <dataset-name> \
+  s3-key-prefix \
+  <key-prefix-url>
+```
 
-If you wish to compress a single log file, specify the entire path to the log file. However, if
-that log file's path is a prefix of another log file's path, then both log files will be compressed
-(e.g., with two files "logs/syslog" and "logs/syslog.1", a prefix like "logs/syslog" will cause
-both logs to be compressed). This limitation will be addressed in a future release.
+* `<key-prefix-url>` is a URL identifying the S3 key prefix to compress. It can be written in either
+  of two formats:
+  * `https://<bucket-name>.s3.<region-code>.amazonaws.com/<key-prefix>`
+  * `https://s3.<region-code>.amazonaws.com/<bucket-name>/<key-prefix>`
+* The fields in `<key-prefix-url>` are as follows:
+  * `<bucket-name>` is the name of the S3 bucket containing your logs.
+  * `<region-code>` is the AWS region [code][aws-region-codes] for the S3 bucket containing your
+    logs.
+  * `<key-prefix>` is the prefix of all logs you wish to compress and must begin with the
+    `<all-logs-prefix>` value from the [compression IAM policy][compression-iam-policy].
+
+:::{note}
+`s3-key-prefix` mode only accepts a single `<key-prefix-url>` argument. This limitation will be
+addressed in a future release.
 :::
 
-[add-iam-policy]: https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_manage-attach-detach.html#embed-inline-policy-console
 [aws-region-codes]: https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.RegionsAndAvailabilityZones.html#Concepts.RegionsAndAvailabilityZones.Availability
+[aws-s3-object-key]: https://docs.aws.amazon.com/AmazonS3/latest/userguide/object-keys.html
 [compression-iam-policy]: ./object-storage-config.md#configuration-for-compression