adds/updates records; uses jq instead of grep (#2)

* adds a record if it doesn't exist yet; uses jq to extract information more reliably from cloudflare responses

* configuration validation, and defaults for TTL and PROXY; better cloudflare response parsing and error handling/reporting; formatting and comments

* added bash to docker image; errors out when trying to update a CNAME record; creates a new record if one doesn't exist if FORCE_CREATE; runs only once w/o setting up cron if RUNONCE is set; doc updates; removed defaults of env vars (script reports what's missing instead); linted script

.gitignore

@@ -1,3 +1,6 @@
+# File created by running script locally
+ip.dat
+
 # Windows image file caches
 Thumbs.db
 ehthumbs.db
@@ -42,4 +45,4 @@ Network Trash Folder
 Temporary Items
 .apdisk
 
-.idea
+.idea

Dockerfile

@@ -1,19 +1,21 @@
 FROM alpine:3.6
 
 ADD cloudflare.sh /cloudflare.sh
-ADD cron /var/spool/cron/crontabs/root
+ADD crontab /var/spool/cron/crontabs/root
 
-ENV ZONE=example.com \
-    HOST=example.com \
-    [email protected] \
-    API=1111111111111111 \
-    TTL=1 \
-    PROXY=true \
-    DEBUG=false
+ENV ZONE= \
+    HOST= \
+    EMAIL= \
+    API= \
+    TTL= \
+    PROXY= \
+    DEBUG= \
+    FORCE_CREATE= \
+    RUNONCE=
 
-RUN apk add --update curl && \
+RUN apk add --update bash jq curl && \
     rm -rf /var/cache/apk/* && \
     chmod +x /cloudflare.sh
 
 CMD /cloudflare.sh && \
-    crond -f
+    test -z "$RUNONCE" && crond -f

README.md

@@ -1,10 +1,10 @@
 # joshuaavalon/cloudflare-ddns
-[![version](https://images.microbadger.com/badges/version/joshuaavalon/cloudflare-ddns.svg)](https://microbadger.com/images/joshuaavalon/cloudflare-ddns) 
-[![](https://images.microbadger.com/badges/image/joshuaavalon/cloudflare-ddns.svg)](https://microbadger.com/images/joshuaavalon/cloudflare-ddns) 
-![Docker Pulls](https://img.shields.io/docker/pulls/joshuaavalon/cloudflare-ddns.svg) 
-![Docker Stars](https://img.shields.io/docker/stars/joshuaavalon/cloudflare-ddns.svg?colorB=dfb317) 
-[![Docker Automated build](https://img.shields.io/docker/automated/joshuaavalon/cloudflare-ddns.svg)](https://hub.docker.com/r/joshuaavalon/cloudflare-ddns/) 
-[![Docker build](https://img.shields.io/docker/build/joshuaavalon/cloudflare-ddns.svg)](https://hub.docker.com/r/joshuaavalon/cloudflare-ddns/) 
+[![version](https://images.microbadger.com/badges/version/joshuaavalon/cloudflare-ddns.svg)](https://microbadger.com/images/joshuaavalon/cloudflare-ddns)
+[![](https://images.microbadger.com/badges/image/joshuaavalon/cloudflare-ddns.svg)](https://microbadger.com/images/joshuaavalon/cloudflare-ddns)
+![Docker Pulls](https://img.shields.io/docker/pulls/joshuaavalon/cloudflare-ddns.svg)
+![Docker Stars](https://img.shields.io/docker/stars/joshuaavalon/cloudflare-ddns.svg?colorB=dfb317)
+[![Docker Automated build](https://img.shields.io/docker/automated/joshuaavalon/cloudflare-ddns.svg)](https://hub.docker.com/r/joshuaavalon/cloudflare-ddns/)
+[![Docker build](https://img.shields.io/docker/build/joshuaavalon/cloudflare-ddns.svg)](https://hub.docker.com/r/joshuaavalon/cloudflare-ddns/)
 [![MIT](https://img.shields.io/github/license/joshuaavalon/docker-cloudflare.svg)](https://github.com/docker-cloudflare/blob/master/LICENSE)
 
 The is a simple docker using curl to update DNS record on [Cloudflare](https://www.cloudflare.com). Inspired by [rasmusbe/cloudflare-update-record.sh](https://gist.github.com/rasmusbe/fc2e270095f1a3b41348/)
@@ -15,28 +15,49 @@ Compare to [nouchka/cloudflare-dyndns](https://hub.docker.com/r/nouchka/cloudfla
  * Update when IP is changed
 
 ## Usage
+
+### Running once interactively
+
+```
+docker run \
+    -e RUNONCE=1 \
+    -e ZONE=example.com \
+    -e HOST=example.com \
+    -e [email protected] \
+    -e API=1111111111111111 \
+    -e TTL=1 \
+    -e PROXY=true \
+joshuaavalon/cloudflare-ddns
+```
+
+### Running as a daemon
+
 ```
-docker run  \
-	-d \
-	-e ZONE=example.com \
-	-e HOST=example.com \
-	-e [email protected] \
-	-e API=1111111111111111 \
-	-e TTL=1 \
-	-e PROXY=true \
-	--name cloudflare \
+docker run \
+    -d \
+    -e ZONE=example.com \
+    -e HOST=example.com \
+    -e [email protected] \
+    -e API=1111111111111111 \
+    -e TTL=1 \
+    -e PROXY=true \
 joshuaavalon/cloudflare-ddns
 ```
 
+
 ## Parameters
-`ZONE`: Domain, e.g. example.com. Default: `example.com`
+`ZONE`: Domain, e.g. example.com.
+
+`HOST`: DNS record to be updated, e.g. example.com, subdomain.example.com.
+
+`EMAIL`: Cloudflare Email.
 
-`HOST`: DNS record to be updated, e.g. example.com, subdomain.example.com. Default: `example.com`
+`API`: Cloudflare API key.
 
-`EMAIL`: Cloudflare Email. Default: `[email protected]`
+`TTL`: (OPTIONAL) Time to live for DNS record. Value of 1 is 'automatic'. Min value:120; Max value:2147483647. Default: `1`
 
-`API`: Cloudflare API key. Default: `1111111111111111`
+`PROXY`: (OPTIONAL) Whether the record is receiving the performance and security benefits of Cloudflare. `true` to enable; `false` to disable. Default: `true`
 
-`TTL`: Time to live for DNS record. Value of 1 is 'automatic'. Min value:1; Max value:2147483647. Default: `1`
+`FORCE_CREATE`: (OPTIONAL) When set, a record will be created if one does not exist already.
 
-`PROXY`: Whether the record is receiving the performance and security benefits of Cloudflare. `true` to enable; `false` to disable. Default: `true`
+`RUNONCE`: (OPTIONAL) When set, only a single update is attempted, and the script exists without setting up a cron process.

cloudflare.sh

@@ -1,50 +1,157 @@
-#!/bin/sh
+#!/bin/bash
+
+# Enforces required env variables
+required_vars=(ZONE HOST EMAIL API)
+for required_var in "${required_vars[@]}"; do
+    if [[ -z ${!required_var} ]]; then
+        error=1
+        echo >&2 "Error: $required_var env variable not set."
+    fi
+done
+
+if [[ -n $error ]]; then
+    exit 1
+fi
+
+# PROXY defaults to true
+PROXY=${PROXY:-true}
+
+# TTL defaults to 1 (automatic), and is validated
+TTL=${TTL:-1}
+if [[ $TTL != 1 ]] && [[ $TTL -lt 120 || $TTL -gt 2147483647 ]]; then
+    echo >&2 "Error: Invalid TTL value $TTL; must be either 1 (automatic) or between 120 and 2147483647 inclusive."
+    exit 1
+fi
 
 echo "Current time: $(date "+%Y-%m-%d %H:%M:%S")"
-ip_file="ip"
 
+# Determines the current IP address
 new_ip=$(curl -s http://ipecho.net/plain)
 
-# Fallbacks
-if [ -z "$new_ip" ]; then
+# IP address service fallbacks
+if [[ -z $new_ip ]]; then
     new_ip=$(curl -s http://whatismyip.akamai.com)
 fi
-if [ -z "$new_ip" ]; then
+if [[ -z $new_ip ]]; then
     new_ip=$(curl -s http://icanhazip.com/)
 fi
-if [ -z "$new_ip" ]; then
+if [[ -z $new_ip ]]; then
     new_ip=$(curl -s https://tnx.nl/ip)
 fi
 
-if [ -z "$new_ip" ]; then
-    echo "Empty IP !"
-    exit 0
+if [[ -z $new_ip ]]; then
+    echo >&2 "Error: Unable to reach any service to determine the IP address."
+    exit 1
 fi
 
-if [ -f $ip_file ]; then
-  ip=$(cat $ip_file)
-  if [ "$ip" = "$new_ip" ]; then
-    echo "Same ip: $ip"
-    exit 0
-  fi
+# Compares with last IP address set, if any
+ip_file="ip.dat"
+if [[ -f $ip_file ]]; then
+    ip=$(<$ip_file)
+    if [[ $ip = "$new_ip" ]]; then
+        echo "IP is unchanged : $ip. Exiting."
+        exit 0
+    fi
 fi
 
 ip="$new_ip"
 echo "IP: $ip"
-zone_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$ZONE" -H "X-Auth-Email: $EMAIL" -H "X-Auth-Key: $API" -H "Content-Type: application/json" | grep -Eo '"id":.?"\w*?"' |head -1|grep -o ':.*".*"'|grep -o '\w*')
-echo "Zone ID: $zone_id"
-record_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records?name=$HOST" -H "X-Auth-Email: $EMAIL" -H "X-Auth-Key: $API" -H "Content-Type: application/json" | grep -Eo '"id":.?"\w*?"' |head -1|grep -o ':.*".*"'|grep -o '\w*')
-echo "Record ID: $record_id"
-update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$record_id" -H "X-Auth-Email: $EMAIL" -H "X-Auth-Key: $API" -H "Content-Type: application/json" --data "{\"id\":\"$zone_id\",\"type\":\"A\",\"name\":\"$HOST\",\"content\":\"$ip\",\"ttl\":$TTL,\"proxied\":$PROXY}")
 
-if $DEBUG; then
-  echo "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$record_id" -H "X-Auth-Email: $EMAIL" -H "X-Auth-Key: $API" -H "Content-Type: application/json" --data "{\"id\":\"$zone_id\",\"type\":\"A\",\"name\":\"$HOST\",\"content\":\"$ip\",\"ttl\":$TTL,\"proxied\":$PROXY}"
+# Fetches the zone information for the account
+zone_response=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$ZONE" \
+        -H "X-Auth-Email: $EMAIL" \
+        -H "X-Auth-Key: $API" \
+        -H "Content-Type: application/json")
+
+
+# If not successful, errors out
+if [[ $(jq <<<"$zone_response" -r '.success') != "true" ]]; then
+    messages=$(jq <<<"$zone_response" -r '[.errors[] | .message] |join(" - ")')
+    echo >&2 "Error: $messages"
+    exit 1
+fi
+
+# Selects the zone id
+zone_id=$(jq <<<"$zone_response" -r ".result[0].id")
+
+
+# If no zone id was found for the account, errors out.
+if [[ -z $zone_id ]]; then
+    echo >&2 "Error: Could not determine Zone ID for $ZONE"
+    exit 1
+fi
+
+echo "Zone $ZONE id : $zone_id"
+
+
+# Tries to fetch the record of the host
+dns_record_response=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records?name=$HOST" \
+        -H "X-Auth-Email: $EMAIL" \
+        -H "X-Auth-Key: $API" \
+        -H "Content-Type: application/json")
+
+if [[ $(jq <<<"$dns_record_response" -r '.success') != "true" ]]; then
+    messages=$(jq <<<"$dns_record_response" -r '[.errors[] | .message] |join(" - ")')
+    echo >&2 "Error: $messages"
+    exit 1
+fi
+
+# DNS record to add or update
+read -r -d '' new_dns_record <<EOF
+{
+    "type": "A",
+    "name": "$HOST",
+    "content": "$ip",
+    "ttl": $TTL,
+    "priority": 10,
+    "proxied": $PROXY
+}
+EOF
+
+# Adds or updates the record
+dns_record_id=$(jq <<<"$dns_record_response" -r '.result[] | select(.type =="A") |.id')
+if [[ -z $dns_record_id ]]; then
+
+    # Makes sure we don't have a CNAME by the same name first
+    cname_dns_record=$(jq <<<"$dns_record_response" -r '.result[] | select(.type =="CNAME")')
+    if [[ -n $(jq <<<"$cname_dns_record" -r '.id') ]]; then
+        dns_record_content=$(jq <<<"$cname_dns_record" -r '.content')
+        echo >&2 "Error: CNAME entry found for $HOST. Remove it or set HOST=$dns_record_content instead."
+        exit 1
+    fi
+
+    # If not asked to create a record, stops
+    if [[ -z $FORCE_CREATE ]]; then
+        echo >&2 "Error: No existing record. Set FORCE_CREATE to any value to force its creation."
+        exit 1
+    fi
+
+    # Creates a new record
+    echo "Creating new record for host $HOST"
+
+    dns_record_response=$(curl -s -X POST "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records" \
+            -H "X-Auth-Email: $EMAIL" \
+            -H "X-Auth-Key: $API" \
+            -H "Content-Type: application/json" \
+            --data "$new_dns_record")
+else
+    # If a record is found, updates the existing record
+    echo "Updating record $dns_record_id for host $HOST"
+
+    dns_record_response=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$dns_record_id" \
+            -H "X-Auth-Email: $EMAIL" \
+            -H "X-Auth-Key: $API" \
+            -H "Content-Type: application/json" \
+            --data "$new_dns_record")
 fi
 
-if echo "$update" | grep -q "\"success\":true"; then
-    echo "IP changed to: $ip"	
-  echo "$ip" > $ip_file
+if [[  $(jq <<<"$dns_record_response" -r '.success') = "true" ]]; then
+    # Records the IP set set if successful
+    echo "IP changed to: $ip"
+    echo "$ip" > $ip_file
 else
-  printf "Update failed:\\n%s" "$update"
-  exit 1
+    # Prints out error messages if unsuccessful
+    messages=$(jq <<<"$dns_record_response" -r '[.errors[] | .error.message] |join(" - ")')
+    echo >&2 "Error: $messages"
+    exit 1
 fi