enhance documentation

mithril-aggregator-fake/README.md

@@ -30,17 +30,32 @@ For each file, the identifiers of the corresponding artifacts are extracted and
 
 If a file is missing or incomplete, the software will stop with an error message.
 
+This project comes with a shell script that reads data from a given Mithril Aggregator URL and creates the data files in a directory:
+
+```
+./scripts/import.sh some/data/directory http://valid.mithril.url/aggregator
+```
+
 ## Command line synopsis
 
-Usage: `mithril-fake-aggregator [OPTIONS]`
+Usage: `mithril-aggregator-fake [OPTIONS]`
 
 Options:
 
 ```
   -d, --data-directory <DATA_DIRECTORY>  Directory where the response files are located
-  -v, --verbose...                       Verbose mode (-q, -v, -vv, -vvv, etc)
+  -v, --verbose...                       Verbose mode (-v, -vv, -vvv, etc)
+  -q, --quiet                            Quiet mode. Suppress all outputs.
   -p, --tcp-port <TCP_PORT>              TCP port to listen on [default: 80]
   -i, --ip-address <IP_ADDRESS>          IP Address to bind server to [default: 127.0.0.1]
   -h, --help                             Print help
   -V, --version                          Print version
 ```
+
+## Examples
+
+Launching the fake Aggregator on `127.0.0.1:80` (requires root privileges) using builtin data with the ERROR verbose level:
+`./mithril-aggregator-fake`
+
+Launching the fake Aggregator on `127.0.0.1:8000` reading data from `some/data/directory` subdirectory with the INFO verbose level:
+`./mithril-aggregator-fake -p 8000 -d some/data/directory -vv`

mithril-aggregator-fake/scripts/import.sh

@@ -1,9 +1,26 @@
 #!/usr/bin/env bash
 set +a -eu -o pipefail
-#set -v
+#set -vx
+
+check_requirements() {
+    which wget >/dev/null ||
+        error "It seems 'wget' is not installed or not in the path.";
+}
+
+display_help() {
+    if [ -n "${1-""}" ]; then echo "ERROR: ${1}"; echo; fi
+    echo "HELP"
+    echo $0
+    echo
+    echo "Import and save data from a given Mithril Aggregator."
+    echo
+    echo "Usage: $0 DATA_DIRECTORY URL"
+    echo
+    exit 1;
+}
 
 error() {
-    echo $1;
+    echo "ERROR: $1";
     exit 1;
 }
 
@@ -63,14 +80,18 @@ download_certificate_chain() {
 
 # MAIN execution
 
-declare -r DATA_DIR=${1:?"No data directory given to download JSON files."};
-declare -r BASE_URL=${2:?"No Mithril Aggregator URL given."};
+if [ -z "${1-""}" ]; then display_help "No data directory given to download JSON files."; fi;
+if [ -z "${2-""}" ]; then display_help "No Mithril Aggregator URL given."; fi;
+
+declare -r DATA_DIR=$1;
+declare -r BASE_URL=$2;
 
 if [ ! -d "$DATA_DIR" ]; then error "Specified directory '${DATA_DIR}' is not a directory."; fi
-wget --quiet --server-response --spider $BASE_URL || error "Could not reach URL '${BASE_URL}'.";
+wget --quiet --server-response --spider $BASE_URL 2>/dev/null || error "Could not reach URL '${BASE_URL}'.";
 
 export DATA_DIR URL;
 
+check_requirements;
 clean_directory;
 
 download_list "$BASE_URL/certificates" "certificates"